Help me choose a suspension setup

JJ427R

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Having seen your incredibly slow lap times (in some cases 10 sec/lap slower than the slowest road race class, Spec Miata), a supreme lack of lap time consistency (with best lap times as much as a 7 sec different from one session to the next), and your loud and repeated endorsement of your own driving abilities... I'd say this applies here. And of course a meme says a 1,000 words...

Since you like my videos so well, here's my last track days at Road America with Northwood Shelby and my best 5 laps. How many cars do I pass and how many pass me? about 50 cars in my run group..... lap times 2:57, 2:58, 2:57, 3:01, 2:58 fairly consistent I'd say, one handed with hand controls as well... :D
And note I hit my apex's
This is in my 2018 GT PP1, first weekend on track with it....

 
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JJ427R

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One more item related to track etiquette, I drive with hand controls so similar to a car with a closed cockpit I cannot signal with my hands out my drivers window, so I use my turn signals to signal drivers by me. I always discuss this in the drivers meetings to make all other drivers on track and the track safety workers aware. I've never had an incident on track and many compliments from other drivers regarding this.
 

kcbrown

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Of course you do. And I can explain why. See the definition of the Dunning–Kruger effect:

Why you felt the need to go there, I'll never know. In the context of this discussion, I had a very specific meaning in mind for "truly capable": someone who can reliably take the car to its limits and keep it there. Only with someone with that level of capability at the wheel can you properly assess the performance effects of any given modification. They have to be capable of keeping their lap time variations down to tenths of a second or smaller while keeping the car at its absolute limits.

I thought I had made that clear in followup messages, which is why I find it a bit perplexing that you felt the need to go here now. Have you not kept up with the thread or something (seeing and responding to the message you responded to before you saw the followup messages would certainly explain it)?
 
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frank s

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As long as we're dealing in pseudo-sophisticated psychological cudgels, I'll suggest we see if "Projection" and/or "Reaction Formation" have a place in this fight.
 

stevbd

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Holy cow what a frickin' train wreck this thread has become the last few pages. It somehow went from frame rails to Everything That's Wrong With The Internet. A few things are true:

1. Some people here really need to chill out a notch or 10. What a bunch of small hand d*&K swinging. Pretty sure anyone with enough talent and experience to really pay the rent with their race winnings isn't hanging out anywhere near this thread. A little perspective please.

2. Words like talent and ability are getting thrown around real loosely. What we're really talking about is experience and resources. Not at all the same thing. Usually about 95 percent of people have roughly the same amount of raw ability and the differences in life come down to practice, experience, and hard work. Maybe 4 percent really can't do something and then the top 1 percent are in F1 or the NFL. Again, no one on here.

3. It's not a sign of weakness to disagree with someone without just totally having to trash them as a person. The lack of self-confidence that oozes from these super personal attacks is really tedious. Just a simple idea, when you start trashing someone's wife over frame rails, or having your wife defend your position on frame rails, it's probably time to look up from the keyboard and tap the brakes. Seriously WTF.

4. People seem to be talking past each other because while computer analysis and engineering may say something is true, computers don't drive cars (at least not all the time). So anything that helps a human driver feel more comfortable, confident, and "in the zone" with what their car is doing is likely to make measurable improvements in lap times. It could be the shade of sunglasses you like to wear, a pair of shoes that are comfortable, or maybe even a frame rail brace. If it makes a particular person more dialed in with what they are trying to do and what the car is doing around them, that's not confirmation bias or peddling BS, it's a real improvement FOR THAT PERSON.

5. The improvement that comes with better driver confidence applies at every level and is real, however you personally find it. For me I'm new to this sport and was looking to do some basics so I bought Terry's street pro suspension setup - great setup by the way, highly recommend it - and came on here all excited about how I dropped 9 seconds from 2.05 to 1.56 on our local track. How much of that was me learning the sport, and the track, and just enjoying a more settled car at speed, as opposed to actual extra grip from Bilsteins and camber plates? Probably 7 seconds or more, right? If Terry does the back to back, maybe the extra confidence as opposed to the actual extra grip is worth 2 seconds or so. Randy Pobst, maybe half a second. But the extra level of subjective "confidence" that can come from a part is real if it feels real to that particular person. It applies to drivers of all levels of experience, and it makes a real difference when a human being is driving a car. Is my 7 seconds a result of someone peddling BS? Of course not. It's real to me.

6. That said, JJ I respectfully disagree that frame rails are going to give you multiple seconds of actual, measurable extra grip on a track. I'm not even sure at this point if that is what you are saying or not. But regardless, I can easily see how the peace of mind that might come FOR YOU with knowing you have some extra strengthening on the car could make you more dialed in with what the car is doing and therefore faster. For whatever reason they seem to work FOR YOU which is awesome!

7. Extra confidence is an advantage no matter how you find it. Practice, experience, big tires, or frame rails, whatever works.

8. This is America, buy what you like and enjoy it. I don't need to be so aggressively coddled and protected from a misguided frame rail brace purchase.

Have fun everyone.
 

kcbrown

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Holy cow what a frickin' train wreck this thread has become the last few pages.

[lots more good stuff]

Have fun everyone.

Nailed it. I really do think we have people talking past each other here. There is one thing you mentioned that I wanted to address:

The improvement that comes with better driver confidence applies at every level and is real, however you personally find it.

That's very likely true. But there's a specific implication of it: the greater the amount of improvement seen as a result of improved driver confidence, the smaller the degree of the driver's capability to wring out the last bit of performance from the car (at least before the modification), and thus the less qualified the driver is to determine the objective improvement from a modification. Suppose, for instance, that a given modification, through driver confidence improvement alone (no objective change in grip), yields a 2 second lap time improvement. That means the driver was leaving 2 seconds on the table. But that means, for any modification that yields a grip improvement of 2 seconds or less, the driver would be unable to say whether the improvement from that modification is from improved confidence or from actual improvement in grip. This is why I say that if you want to know whether a modification objectively improves the performance of the car, you need a driver that can take the car to its limits and keep it there, and keep his lap time variation down to the tenths of a second range or better. You basically need a Randy Pobst, in other words.

This makes it quite difficult to properly assess the objective benefits of a given modification, because few modifications are tested by drivers with that level of capability. For instance, let's say that Terry Fair's lap times can improve by as much as 2 seconds as a result of a driver confidence modification. If that were the case, it would mean that if he were to claim less than 2 seconds a lap improvement for a given modification, he could not legitimately say whether that improvement was due to objective improvements in grip or due to driver confidence. There may be ways of determining some of that through instrumentation, but even those methods might be useless, because it presumes that a change in detected grip (e.g., through G force measurement) is the result of the car driving differently rather than the driver driving differently, something that you simply can't say unless the driver is of the Randy Pobst variety -- which leads right back to my original assertion.
 
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stevbd

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That's a good point. No doubt a less experienced driver is less consistent and it's harder to get repeatable results.

That said, I think it's confusing to refer to certain modifications as being "objective," with the inference that other mods are "subjective" or placebos. As I see it mods basically fall into two categories: The first are those things that make the car actually go, stop, and turn faster (things like big tires, more power, etc.). These mods are pretty easy to measure and comprehend. 305 track tires stick better than 235 snow tires, 400 hp is more than 300 hp, that sort of thing. And a good driver can measure the lap time improvement, with Randy Pobst being a better tester than the rest of us.

The second category consists of those things that help communicate what the car is doing better to its driver (things like good fitting seats, harnesses, pedal and steering feel, good sightlines, etc.) Improvements in this category are just as valid and important (or "objective") as improvements in the first, but they are much harder to measure. And because they involve making a machine communicate with a human, what works for me might not work for you. How much time is an excellent fitting seat worth? How about brakes where you can really feel threshold braking? A suspension where you can feel through your hands and your butt exactly what the tires are doing? None of these things technically add grip at the pavement but for sure they lead to better lap times.

I suppose there is a third category which consists of things that neither make the car faster nor make it communicate better to its driver. Things like hood stripes. And obviously some people on this thread put frame rails in this category. But my thinking is whether it works for me or not, if hood stripes make you feel fast, and for some reason make you more aware of and dialed in with what your car is doing, then for you they are a valuable and objective mod. Go for it, I say, and enjoy. Hell I might try hood stripes myself some day, why not.

By saying that, I express no opinion on whether frame rails are like hood stripes or not!
 

kcbrown

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That's a good point. No doubt a less experienced driver is less consistent and it's harder to get repeatable results.

Right, but it's not just that. Even if the less experienced driver were very consistent, it's precisely because they're not consistently driving the car at its limit that they'd be unable to properly assess a modification's objective improvement. You'd somehow have to know the difference between the objective portion of the improvement and the subjective portion, something that I dare say is essentially impossible.

That said, I think it's confusing to refer to certain modifications as being "objective," with the inference that other mods are "subjective" or placebos.

Oh, don't get me wrong, some (perhaps even most) mods incorporate some of both.

By an "objective" modification, I mean one that actually expands the performance envelope of the car itself, an improvement that is entirely driver-independent. A perfect example is the move to slicks from street tires, as you recognize below. The grip limits are expanded and that's pretty much that. It's an objective improvement.

As I see it mods basically fall into two categories: The first are those things that make the car actually go, stop, and turn faster (things like big tires, more power, etc.). These mods are pretty easy to measure and comprehend. 305 track tires stick better than 235 snow tires, 400 hp is more than 300 hp, that sort of thing. And a good driver can measure the lap time improvement, with Randy Pobst being a better tester than the rest of us.

Exactly. That's the sort of modification I would call "objective".

The second category consists of those things that help communicate what the car is doing better to its driver (things like good fitting seats, harnesses, pedal and steering feel, good sightlines, etc.) Improvements in this category are just as valid and important (or "objective") as improvements in the first, but they are much harder to measure. And because they involve making a machine communicate with a human, what works for me might not work for you. How much time is an excellent fitting seat worth? How about brakes where you can really feel threshold braking? A suspension where you can feel through your hands and your butt exactly what the tires are doing? None of these things technically add grip at the pavement but for sure they lead to better lap times.

Oh, absolutely. And for brevity, let's call these mods "subjective" ones. But here's the rub: the more capable the driver, the less such modifications matter. Which is to say, the greater the capability of the driver, the smaller the amount of lap time difference one should expect to see from this kind of modification. At the extreme you have the "perfect driver", someone who would be capable of keeping the car at its absolute limits while following exactly the same optimal line around the track. Absent random environmental variations from lap to lap, such a person would be able to keep the lap time variation down to zero. That would make them the perfect candidate to test objective modifications, but the worst candidate to test the effectiveness of subjective ones, because they would have no need for them. Yes, they might be able to feel the difference, and they might even be able to say roughly how much easier the mod makes it for them to achieve the lap time the car is capable of, but how do you translate that to lap time improvements for imperfect drivers? I don't think you can. And that's not a surprise: a subjective modification's effect is driver-dependent, to the point that a given modification might make things worse for some drivers while making it better for others. We're now squarely into driver preference territory, the very definition of subjectiveness.

I suppose there is a third category which consists of things that neither make the car faster nor make it communicate better to its driver. Things like hood stripes.

Oddly enough, one could argue that hood stripes could make the car communicate better to the driver, because they could make it easier for the driver to position the car. :)

And obviously some people on this thread put frame rails in this category.

They do. And I think that's probably a mistake. They'd have to show that the rails have no effect whatsoever on the feel of the car, but about the only way you could do that would be to show, through structural analysis or through other objective measurement, that the rails make no changes at all to the structural characteristics of the car. Good Luck With That. Absent such an indication, they have no legitimate basis for their claim. Now, that said, it's usually on the claimant to back their claim with evidence. Someone who claims a lap time improvement from a subjective modification would need to provide some evidence of it. But really, before-and-after lap times from that person would generally be sufficient to at least introduce the reasonable possibility that there was subjective improvement in the handling of the car. To dispute the claim at that point without structural data is to make a baseless claim, which is exactly what Terry Fair has done in this thread. And the irony of that is quite thick, seeing how many of the modifications he sells are largely of the confidence-based variety, which I dare say even includes the street pro setup you bought (multiple people have said very good things about it so I have no doubt that it's a worthwhile modification -- just saying that if you were to hand your car to Randy Pobst before and after the upgrade, he'd probably see very little lap time improvement).

But my thinking is whether it works for me or not, if hood stripes make you feel fast, and for some reason make you more aware of and dialed in with what your car is doing, then for you they are a valuable and objective mod. Go for it, I say, and enjoy. Hell I might try hood stripes myself some day, why not.

I'd still call it a subjective mod, because its effects are driver-dependent. But regardless of that, I fully agree: if you like what a given mod does for you, that's all that really matters in the end. And I use my own car as an example of that. The suspension modifications I've made (essentially, I've taken a GT Track Package version and turned it into a Boss 302 that has Koni Sport dampers and a GT engine) probably don't make the car any faster, really (if they do, it'll be minimal), but they make it a lot more fun for me to drive. Who can argue against that?
 
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stevbd

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Basically all I'm saying is that lap times can be improved not only with modifications that make the car actually turn, stop, and go faster (what you are calling "objective" mods), but also with upgrades that improve that important line of communication between the car and its driver (what you are calling "subjective" mods). And when it comes to this line of communication, I think stock Mustangs can sometimes be quite muddy machines.

I agree this second "communication" category tends to be harder to measure and more a function of personal preferences, but I wouldn't say it is totally "subjective" or only a matter of personal beliefs and opinions. It is real and critical TO DRIVERS OF ALL LEVELS in order to access 100 percent of the car's potential. It's hard even for the most experienced driver to drive a car that doesn't communicate well. Why do you think all the BMW and Porsche fanatics are so up in arms with electric steering? They're complaining about a lack of feel and feedback, a lack of communication.

Certain cars and modifications unquestionably improve this important line of communication between the vehicle and its driver. Whether frame rail braces fall into this category I have no idea, but it doesn't seem impossible. The LS boss removes the rear seat and adds an x-brace, for example, supposedly to increase chassis rigidity and presumably add some type of "feel." At least for JJ, frame rail braces seem to do the same. So who am I to say he's wrong? At a minimum I have to respect it's not just a black or white discussion of whether the frame rails "add grip."
 

rwleonard

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I am one of those guys who is just trying to have fun with a car he loves. Lap times are the last thing I am worried about, I try to drive at a pace that is exhilarating, but not terrifying. As I get more seat time, that pace gradually increases without my really pushing, or even noticing.

All that to lead up to this: I have done a lot to the suspension/brakes in the car. I don't drive anywhere near well enough to know if most of it mattered (I do know tires mattered), i.e., I would not be at all surprised to find that a good driver could have turned better lap times with the stock car vs what I am doing now, with fairly extensive mods. However, every one of the mods made the car more enjoyable to drive...for me. It's my car, my money, my fun, so that's all that really matters.

(Before someone chimes in with "Maybe you should have spent the money on seat time..." I just want to say, duh. Work and family, not budget, limit my seat time.)
 

kcbrown

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I agree this second "communication" category tends to be harder to measure and more a function of personal preferences, but I wouldn't say it is totally "subjective" or only a matter of personal beliefs and opinions.

I agree, within limits. It's not so much that mods in the communication category are a matter of personal beliefs and opinions (that implies some amount of conscious control over the effectiveness of the mod to the driver, something that I don't believe is there), but rather that their effectiveness is driver-dependent. And let me be clear: by "effectiveness" I mean the degree to which it enables the driver to drive the car faster or the ease with which they can drive the car at its limits. There are some nuances that come into play here, but for the most part, as long as the car communicates the necessary information to the driver somehow, a "perfect" driver will not be able to drive the car any faster as a result of the mods in question, though they may make it easier for him to do that.

It is real and critical TO DRIVERS OF ALL LEVELS in order to access 100 percent of the car's potential. It's hard even for the most experienced driver to drive a car that doesn't communicate well. Why do you think all the BMW and Porsche fanatics are so up in arms with electric steering? They're complaining about a lack of feel and feedback, a lack of communication.

Oh, I completely agree. And yet, I would wager that the very best drivers would still be able to get every bit of performance out of these cars with electric steering, despite the suboptimal feel of the steering. Which is to say, I suspect that a steering mod that restored the original steering feel would make it easier for the very best drivers to get the most out of the car, but wouldn't change whether it's possible for them to do so.

Certain cars and modifications unquestionably improve this important line of communication between the vehicle and its driver. Whether frame rail braces fall into this category I have no idea, but it doesn't seem impossible. The LS boss removes the rear seat and adds an x-brace, for example, supposedly to increase chassis rigidity and presumably add some type of "feel." At least for JJ, frame rail braces seem to do the same. So who am I to say he's wrong?

Exactly. And who are any of us, really? Like I said, in order to disprove his assertion that he can drive the car faster with the rails in place than without them, you'd have to show that the frame rails make no alteration whatsoever to the car's physical characteristics. Good Luck With That. It looks like Terry Fair's group did some stiffness tests of the tub, and concluded that there was sufficient stiffness that further bracing would yield no appreciable stiffness changes, but that doesn't automatically mean that further stiffening will have no effect on how the car communicates to the driver. There's a difference between saying that there's no appreciable change and no change at all, but it's the latter that one would have to assert and prove in order to be able to conclude that there's no change in how/what the car communicates to the driver.

And there's an additional attribute of the tub that I bet Terry and his crew did not test: the frequency response characteristics of the tub with and without stiffening. The tub is an elastic structure like anything else. The various movements of the suspension will generate shock impulses that will move through the tub. Those impulses will be composed of various frequency/amplitude components that, when added together, form the impulse. A perfectly rigid tub will perfectly telegraph the entire frequency spectrum through it, but we're not talking about a tub that's perfectly rigid -- we're talking about one that has some flexibility. And that flexibility will be frequency-dependent. Which is to say, it'll transmit some frequencies better than others. The end result is that the impulse seen by the other end of the tub will be different than the impulse seen by the originating side, with some parts of the spectrum damped relative to other parts. Bracing will almost certainly change the frequency response characteristics of the tub. While I have no reason to believe that any significant change in grip would arise, I can easily envision it changing the feel of the car, and in particular the way the road feels through the car. I'd be very interested in Norm's thoughts on this.

At a minimum I have to respect it's not just a black or white discussion of whether the frame rails "add grip."

I think we can objectively say they don't "add grip", because grip is an objective measure and that is something that a sufficiently capable driver would be able to show. But we can't say they don't make a lap time difference, because that is the result of a combination of the physical grip characteristics of the car, how well the car's handling characteristics fit in with the driver's preferences, and the clarity with which the car communicates to the driver in a way the driver can understand and make use of. The bracing in question almost certainly doesn't improve the first, probably doesn't change the second, but could easily change the third.
 

kcbrown

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(Before someone chimes in with "Maybe you should have spent the money on seat time..." I just want to say, duh. Work and family, not budget, limit my seat time.)

I won't say you should have spent the money on seat time. Because your goal isn't to get the fastest lap times, your goal is to have a big pile of fun while driving the car at speed. If a given modification will make the car a lot more fun to drive, the money for it will be paid back every time you drive the car from that point forward, which makes it an excellent investment in light of your goal, irrespective of its effects on your lap times.

No, it's really only those people for whom lap times is the only thing that matters that I'd argue for seat time in lieu of everything else (save for reliability or safety mods).
 
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Norm Peterson

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And there's an additional attribute of the tub that I bet Terry and his crew did not test: the frequency response characteristics of the tub with and without stiffening. The tub is an elastic structure like anything else. The various movements of the suspension will generate shock impulses that will move through the tub. Those impulses will be composed of various frequency/amplitude components that, when added together, form the impulse. A perfectly rigid tub will perfectly telegraph the entire frequency spectrum through it, but we're not talking about a tub that's perfectly rigid -- we're talking about one that has some flexibility. And that flexibility will be frequency-dependent. Which is to say, it'll transmit some frequencies better than others. The end result is that the impulse seen by the other end of the tub will be different than the impulse seen by the originating side, with some parts of the spectrum damped relative to other parts. Bracing will almost certainly change the frequency response characteristics of the tub. While I have no reason to believe that any significant change in grip would arise, I can easily envision it changing the feel of the car, and in particular the way the road feels through the car. I'd be very interested in Norm's thoughts on this.
Any time you add mass or introduce additional stiffening, structural vibration modeshapes change, and not all of them by the same amount. Some modeshapes - the locations where they peak and what the magnitudes of those peaks might have originally been - are effectively eliminated, and others are chased off to higher frequencies where they generally don't matter as much. Structural frequencies tend to be well above suspension frequencies, so there isn't likely to be much 'coupling' going on with or without additional stiffening.

I'm glad you said 'significant change'. And 'significant' is an important qualifier even regarding explanations made on a purely static level, where if a structure starts out being relatively stiff there simply isn't much improvement to be had even if you could eliminate it all. Crudely, that's because you can't remove a whole degree of twist from a chassis that's only twisting by a quarter of a degree.

I guess you have to be able to at least generally quantify how much flexibility exists (not a whole lot in the S197's case), and how much more stiffness you'd have to add to reduce it by enough to matter (a huge amount). Then relate that back to how effectively LLT is being dragged to the end of the car with "too much" roll resistance (relative to the weight on that end) from the other end.



I think we can objectively say they don't "add grip", because grip is an objective measure and that is something that a sufficiently capable driver would be able to show.
Theoretically, they could. By a little. Sort of. But that would also be tied to the specific details of the suspension tuning - how good it might already be at balancing front vs rear grip relative to what the driver prefers. Lap time improvement is possible, but I sure wouldn't be looking for any big objective gains here.



But we can't say they don't make a lap time difference, because that is the result of a combination of the physical grip characteristics of the car, how well the car's handling characteristics fit in with the driver's preferences, and the clarity with which the car communicates to the driver in a way the driver can understand and make use of. The bracing in question almost certainly doesn't improve the first, probably doesn't change the second, but could easily change the third.
Sounds about right.


Norm
 

kcbrown

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Any time you add mass or introduce additional stiffening, structural vibration modeshapes change, and not all of them by the same amount. Some modeshapes - the locations where they peak and what the magnitudes of those peaks might have originally been - are effectively eliminated, and others are chased off to higher frequencies where they generally don't matter as much. Structural frequencies tend to be well above suspension frequencies, so there isn't likely to be much 'coupling' going on with or without additional stiffening.

Hmm...OK, that's primarily what I wasn't sure of. I suppose that even a square wave has linearly decaying frequency components, and a damped impulse (which is what I'd expect the primary shape of a bump from the suspension would look like) would (I expect) see the frequency components decaying even faster, so unless the tub's frequency response is largely within the same range of the frequencies generated by the suspension (sounds like it's nowhere close), then I can't see how structural changes to the tub would have a noticeable impact on the impulse transfer characteristics.

I'm glad you said 'significant change'. And 'significant' is an important qualifier even regarding explanations made on a purely static level, where if a structure starts out being relatively stiff there simply isn't much improvement to be had even if you could eliminate it all. Crudely, that's because you can't remove a whole degree of twist from a chassis that's only twisting by a quarter of a degree.

Right. But what really matters is the amount of influence the twist reduction has on the rest of the system. If that function is highly nonlinear, or linear but with very high multipliers, then you might not need to change the stiffness much in order to see substantial changes elsewhere (that's not to say that such a thing is necessarily physically possible with these systems, and I frankly don't see how it could be). That's something that can be determined through testing, and that's something Terry Fair's crew is good at. So when they say that stiffening the tub has no appreciable effect on the amount of grip or on the handling itself, I'm inclined to believe them.

Theoretically, they could. By a little. Sort of. But that would also be tied to the specific details of the suspension tuning - how good it might already be at balancing front vs rear grip relative to what the driver prefers. Lap time improvement is possible, but I sure wouldn't be looking for any big objective gains here.

It's difficult to see how any substantial objective gains could be had anyway, if the stiffness increase is minimal and the frequency response of the tub doesn't change substantially at the frequencies generated by the suspension. But this presumes the change in LLT characteristics or in total grip is a gradual function of tub stiffness change. If small changes in stiffness yield large changes in LLT characteristics or in total grip, then all bets are off (and I can't see how that would work in any case just from a physical standpoint). But that is something that should be objectively observable by a really good driver.

Sounds about right.

Well, the real problem is that we're now left with the question of how the change could possibly improve driver communication, if the frequency response changes are in frequency ranges that are barely generated by the suspension in the first place.
 
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JJ427R

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I wish everyone would quit speculating what changes these might make and listen to just a little bit of what we on here who have installed them have said they do. All I said initially is I felt the Matrix brace contributed greatly in improving my lap times at BIR 2 seconds from my previous track day, and as I also stated that yes I hope to improve my driving skill every time I get on the track, and if I'm a good driver I should improve every time, but we don't know if it was just me, the addition of the brace, or both? I said in my opinion I believe it was more related to the Matrix brace and I'm sticking to that theory so to speak.

I gave my track times prior and after the brace to Norm, who did his graph earlier in this thread to show some type of data. Coincidently it did show quite a decrease after the brace and Norm even stated he was surprised, and he initially was one of the biggest critics. Has it change his opinion, only he can say that, but at least he was trying to be objective about it.

Now I'm the only one who has given any data regarding these braces, we cant' find anything online and we don't have any data to support it doesn't change things, only opinions. We've also yet to hear from anyone who has installed one come on here and say they did nothing for them, and as I stated previously I have noting at all to gain by coming on here and giving my opinion of them, I'm not manufacturing them or selling them for anyone, and in no way am I trying to justify my purchase or "Placebo Effect" as some stated.

As stiff as these cars may be, with the addition of the KB matrix brace and jacking rails, or in Pentalab's case the BMR subframe connectors, our cars both became much stiffer, and we both have said this is quite noticeable the first time you drive it. As Pentalab stated "any idiot could feel the difference". I could not agree with his statement more, and I did not have to get it on track to notice this difference. Now some say they are unsure if it really makes any difference on track, and all I said is I believe it does, as I noticed a difference in how my car felt on the track prior to these being installed, and I did notice decrease in my lap times at both BIR and Road America. Regarding stiffness, how does anyone know it's stiff enough and can it get too stiff? Any woman would probably say no!! ;)

It's quite obvious we will come to no conclusion on this, and I had no idea my comments on this would become such a Psychoanalytic discussion, think were going off the deep end here with all of that. I think its time to put this to rest and give the OP his thread back.

I thank you all who have given serious input to this discussion. I'm checking out...
 
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kcbrown

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I wish everyone would quit speculating what changes these might make and listen to just a little bit of what we on here who have installed them have said they do.

It's human nature to be curious about how and why things work. The speculation here (on my part, at least) isn't whether the brace makes any changes to the feel of the car, but how. Put another way, I am not questioning your claim that they change the feel of the car. I'm attempting to understand why they do.
 

Norm Peterson

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I gave my track times prior and after the brace to Norm, who did his graph earlier in this thread to show some type of data. Coincidently it did show quite a decrease after the brace and Norm even stated he was surprised, and he initially was one of the biggest critics. Has it change his opinion, only he can say that, but at least he was trying to be objective about it.
Understand that I wasn't questioning the improvements themselves. Only where the majority of the credit for those improvements properly belongs.

If it felt that much better with the bracing - I'm not questioning that either - you will be able to drive it harder and more than likely with greater consistency. You're now trusting your car better because it actually feels more solid or whatever other description of 'better' might apply. So you push it just that little bit harder because now it feels like you've got that little extra margin to work with, where before it didn't and you held a little back. That's what the greater amount of 'scatter' in the 'without' laps is telling me, that on some laps you weren't as comfortable as you were on other laps and dialed things back a tiny bit on those laps.

Too bad you don't have 'before' and 'after' datalog traces of speeds and g's.


Norm
 

JJ427R

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Of course you do. And I can explain why. See the definition of the Dunning–Kruger effect:

...people that assess their own ability as greater than it is. It is related to the cognitive bias of illusory superiority and comes from the inability of people to recognize their lack of ability. Essentially, low ability people do not possess the skills needed to recognize their own incompetence.

Having seen your incredibly slow lap times (in some cases 10 sec/lap slower than the slowest road race class, Spec Miata), a supreme lack of lap time consistency (with best lap times as much as a 7 sec different from one session to the next), and your loud and repeated endorsement of your own driving abilities... I'd say this applies here. And of course a meme says a 1,000 words...

i-mSH2FwV-L.jpg


There's an old saying about "never insult a man's ability to drive, fight, or f**k", but it's hard not to when they give you all of the evidence (lap times) then argue against this painful reality. Just putting in "25 track days" does not make you: fast, consistent, or somehow make your opinion of some bolt-on doo-dad worthy of merit. Lap times say so much... and when they just aren't anywhere near where a fast person's would be, your opinion gets ignored. As it should.

P7A_7874-L.jpg


I've worked with instructing HPDE students for over 30 years, and try to help new folks or even "the regulars" who want to learn how to go faster. The best way to help folks see "where they are" is to take them for a ride-along on a 90% pace or faster lap. Experiencing a lap first hand in a car that is 10-20+ sec a lap faster than they are has an AMAZING effect: it resets their parameters. I cannot count how many folks have said this - " I had no idea how slow I was until I rode with (someone fast)". With helmet-comms you can hear the moment they realize this. I've seen people get emotional, start to tear up... hell, when I am right seat with a student see them make a "quantum leap" over the course of several sessions or days, -I- get emotional too. It's very rewarding to see someone you have been coaching get to the next level.

And at the hundreds of track events I've driven / instructed / competed at, I always see some "regulars" that are stuck. These folks often have years of experience - yet are still super slow. These are the folks that give HPDE a bad name - they "don't see" cars behind them much less give point-bys, tend to be in higher powered cars that can block others on straights in lower power but faster lap time capable cars, usually refuse instruction, yet they always think they are super fast. I usually see them bragging in paddock (or online), usually have the biggest trailer/rig, with some of the highest end equipment.

Of course "JJ427R" is going to take this the wrong way - as the Dunning-Kruger afflicted always do. He will fly off the handle, respond once again with threats of violence, or throw in some completely nonsensical and off topic "example" of his driving greatness. I hope I am wrong this time....

I hate to bring up a dead horse and provoke any confrontation with you Terry but today in other post's on this forum I was reminded of something related to this which you posted about me in the past that I felt you should be made aware of. Also the fact I'm running at Road America in a couple weeks reminded me of it as well. You've made quite a lot of fun about my driving ability and claiming how I'm so slow on track, and you also stated here that you do instructing and coaching, so here is a little eye opener for you.

As I've stated before I've attended BIR's Performance Driving School many times since 2012 and I truly believe they are one of the finest driving schools in the country, with some of the best instructors as well. One of the very first things they tell you in the classroom instruction is it is possible to get killed at 12mph. That may sound funny, but as Gary Curtis instructor there explains, "get on a bicycle and run into a brick wall at that speed and tell me how it feels".

Related to this I had a snowmobile accident in 1993 where I was thrown off my snowmobile into a 3ft tree stump at between 20-30 mph.
I hit head first and compressed two vertebra in my back which has left me Paralyzed from the chest down. I now have steel rods that run the length of my spine. I also broke my left shoulder, both clavicle and scapula, broke my right hip and have a pin and plate in my hip. Also broke 7 ribs, punctured both lungs, spent almost 5 months in the hospital recovering, and almost 2 years of in home rehab. And yes I do set off metal detectors!

So next time you go out on track and complain about someone running too slow, or make jokes about how slow spec Miata's are, try to think about this!
 
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GlassTop09

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Hi All,

Just typing this here to let you all know that I've been reading thru this thread a lot in the background over the last few months gleaning thru all the info posted here & have made some application(s) to my Stang that have made it much more fun to drive, much better connected to it from a "feel perspective" & much more confident in knowing what to expect from it while I'm driving as well......so I do appreciate it all.

Thanks!
:beer:
 

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