School me in suspension

[95ragtop]

So the only mods to the car are steeda springs and I am looking into what to get while I save up for a griggs suspension. FRPP springs can be had for about 300, but then I wonder if I should just spend another 200 and get D specs. Any opinions out there?

 

[Bizzyb0nes]

the Steeda Pro Action Shocks/Struts are made to match up with Steeda's springs...its a good option, however depending on how long it would take to buy your griggs stuff, its probably not worth buying one set, just to turn around and sell it soon after to upgrade...its a purchase you'll definitely lose money on

 

[Gray Ghost GT]

Saving up for a Griggs Suspension is a serious commitment to prepare for HPDE (road course) or Auto-X events. You really don't want to skimp on the other key components. I would avoid the FRPP (Eibach) springs and get the Steeda Ultra-lite/Vogtland Sport springs for only a few extra $$. You will also want maximum adjustability to fine tune your suspension. Take a look at the Koni (Yellow) Adjustable Sport Shocks/Struts vs. a non-adjustable set. You'll also want front camber/caster plates.

 

[Trigger06]

Why avoid the ford racing springs?

 

[Gray Ghost GT]

Why avoid the ford racing springs?

There not a bad spring, but there are much better ones in the market for just a few extra dollars if you plan to do a lot of auto-x or HPDE. If you're on a budget and want a descent upgrade over stock - they're fine. Based on my research given the type of road course activities I'm involved in - I was told by at least two professional drivers that I may be dissappointed with the FRPP springs and I only wanted to do the springs once. Spring rates are subjective based on what you plan to do with your car, etc. YMMV.

 

[mykim72]

steeda has a better spring rate if your looking for performance

 

[SoundGuyDave]

Not giving you grief, but define "better..." The Steeda Competition springs have a higher rate than the FRPP springs, but that may not be the right choice, depending on how the vehicle dynamics, weight, and driving style plays into things.

 

[Pony DNA]

So the only mods to the car are steeda springs and I am looking into what to get while I save up for a griggs suspension. FRPP springs can be had for about 300, but then I wonder if I should just spend another 200 and get D specs. Any opinions out there?

Hi ragtop,

Which Steeda springs do you have, Steeda Sport or Ultralites? What Griggs suspension are you considering? How do you plan to use your car? Be realistic about your needs, this can save you a tremendous headache in terms of time, money and effort when playing with cars. Is this your daily driver? Does it rain and snow much where you live? Are there steep driveways you need to navigate?

The best two bits of absolutely true advice I can give you is "do not lower your car more than one inch" and "buy the best adjustable dampers you can afford or don't bother to change your dampers."

FRPP/Eibach ProKit springs are the same springs! Eibach just sells ProKit springs to FRPP who then sells them to you as Ford Racing Performance Product springs. These are not very good performance springs except on ultra smooth tracks. Any surface irregularity you hit while pushing 10/10's in a corner and you will find yourself with both feet in going for a ride in the sand or tire wall. The reason is that these progressive rate springs set the chassis ride height just a little bit too low and do not have enough spring rate to keep you from bottoming out the suspension. This causes you to end up sitting on the bumpstops so any little bump causes the suspension to go solid which is never healthy for you or the car.

Low is great for looks but bad for handling and ride. If you don't believe me just look at the Mustang FR500C and FR500S race cars on the track in Grand-Am, Koni Challenge or Mustang Challenge series, NONE of them have their ride height set as ridiculously low and they are running 500lb/in front springs and 300lb/in rear springs. Compare these rates to the Eibach/FRPP spring rates 239lb/in (going into coilbind, the working rate is closer to 228lb/in) in front and 215lb/in going into colibind (the working rate is closer to 205lb/in). The tip here is that too low=slow, poor handling and ride. Moderate lowering is the key to retaining good suspension geometry and bump travel which makes your car handle and ride better under more conditions.

Progressive springs are too unpredictable which makes finding that just right damping setting elusive because the spring rate is a moving target. Linear rate design springs are much easier to select and find a good setting your. AFAIK Steeda is the only company making straight rate or linear rate springs for the S197 stock McPherson struts. So I would suggest you keep your Steeda springs and pop a set of adjustable dampers on your car. For an excellent DD car or if you are trying to do things with cost in mind D-Specs are the only player in the market. If money and ride are less an issue and the road course is where you are every weekend then Koni Sports are the best way to go for conventional S197 McPherson struts.

HTH!

 

[Gray Ghost GT]

Excellent write up!

 

[Kaldar142]

pony dna, what if you correct all the suspension geometry? wouldn't lower be better in that case then?

 

[DusterRT]

Well in theory yes, however getting that geometry right is the hard part.

You can only go so far with ball joints, then you can only go so far up with the inboard LCA mounts...at this point an SLA starts sounding pretty good.

Oh and THEN there's the rear end to tackle; LCA's are easy enough with relocation brackets on the axle, but you'll be doing some serious work to raise that UCA mount!

 

[SoundGuyDave]

Nothing that a plasma cutter, TIG welder, and a bunch of steel won't fix... LOL!!

Just dropping the car is going to create more headaches than you'll believe. It's not just camber, caster, and toe, it's pinion angle, roll center, instant center, anti-squat %, anti-dive %, and all of it goes out of whack... Getting it back to where it needs to be is why the race cars you see on the track that ARE slammed, are purpose-built tube-frame silhouette cars, not production body based. The production cars, like the FR500 series, usually aren't lowered all that aggressively. At least the winning ones aren't!

 

[Gray Ghost GT]

I saw the same thing in the Corvette community when guys/gals new to HPDE or road racing would take their "slammed" vettes to the track and quickly realize their handling was horrible partly because there was very limited suspension travel, etc. You quickly figure out what looks cool on the street does not always translate to functionality on the road course. Finding the right balance often takes some trips to the track to figure out what works best for your specific setup. If you're really sophisticated, you'll have a specific suspension setup for each road course you go to since they each offer a unique set of challenges for your car.

 

[Pony DNA]

pony dna, what if you correct all the suspension geometry? wouldn't lower be better in that case then?

Hi Kaldar,

The answer is pretty much my usual "yes but" or "sort of." Once you correct or optimize the front and rear suspension geometry after lowering the car the CG is usually going to be better than before lowering ride height.

The problem is on an S197 chassis you still cannot go any lower due to mechanical interference. With the S197 chassis it is obvious where the issues are, you can see them with the car still on the ground. For starters the top of the struts and the strut mounts, springs going into coil bind, the tires rubbing the inner fender wells, the tires rubbing the fenders, the frame rails over the axle hitting the axle etc. I have already corrected my geometry by installing Steeda's front control arm relocation kit and Steeda X5 balljoints in GT500 front control arms. I have also welded in rear axle lower control arm relocation brackets and installed the outstanding Steeda adjustable Comp/Street UCA and HD adjustable UCA mount. But none of this stuff can overcome the mechanical interference issues of the chassis.

Sure you could fix almost all of these issues but this is a street car no? Whatever you do you don't want to turn your Mustang into one of those um, Asian cars we have all seen slammed one inch off the ground bouncing uncontrollably all over the road every time it runs over some minor bump in the road. That guy has no working suspension, his car is going solid every second it is moving which is why it is all over the road.

Cheers!

 

[95ragtop]

Damn good write up, I wasn't expecting that. Looks like since my car is just a DD for the time and an occasional auto x on the weekend, I will go with D specs. Thanks guys

 

[Pony DNA]

Damn good write up, I wasn't expecting that. Looks like since my car is just a DD for the time and an occasional auto x on the weekend, I will go with D specs. Thanks guys

Hey 95ragtop,

Keep us posted with your impressions once you get those babies installed!

Cheers!

 

[johnQ]

We have put the D-specs on several cars. It is what I have on my personal car as well, which is primarily a street car with the occasional Auto-x and HPDE. Overall, I've been pretty happy with these as it allows some adjustability for the track, but you can still dial it down to retain a decent ride on the street.

 

[Racer X]

Koni Sport shocks are the best in the world, in performance, reliability, and warranty. D-specs, not so much. Save for the Yellows!

 

[Pony DNA]

Koni Sport shocks are the best in the world, in performance, reliability, and warranty. D-specs, not so much. Save for the Yellows!

Hi Racer X,

Actually you would be wrong there. The best dampers in the world depend heavily on the race organizer, race class and the particular chassis on question. For pure damper technology Penske pretty much rules the roost at the moment with their regressive damping technology. But Penske has a more limited range of applications and know exactly what their dampers are worth and charge every penny of it. Olhins and Moton are also outstanding as are AST and JRZ racing dampers for the German and Japanese production chassis. For many production based race cars Konis are very accessable and affordable as are Sachs race dampers for certain chassis like the S197 chassis Mustangs. Koni best in the world? I don't think so.

HTH!

 

[Gray Ghost GT]

For pure damper technology Penske pretty much rules the roost at the moment with their regressive damping technology. But Penske has a more limited range of applications and know exactly what their dampers are worth and charge every penny of it. Olhins and Moton are also outstanding as are AST and JRZ racing dampers for the German and Japanese production chassis. Koni best in the world? I don't think so.

I agree. Koni's are a great reasonably priced adjustable shock/strut for a daily driver that will see some track time, but the Moton, Olhins and Penske are definitely an excellent upgrade and a cut above the rest. Just too much $$$ what what most people need. If my car was a stripped down dedicated track car, I would probably go with Penske or Motons.