Massive RWHP Loss On Dyno

[BruceH]

Do you have a datalog screen shot showing actual spark, rpm, afr, load, and airflow or maf counts?

Did you have a hp number in mind for your motor as currently configured?

 

[ford20]

So you only gained 3HP from going with a Boss IM?

 

[05stroker]

So you only gained 3HP from going with a Boss IM?

No, he only gained 3hp on the same dyno on a different day with different weather.

 

[cyclerick]

Do you have the boss valve springs and billet oil pump gears? I didn't see it in your mods. If not, I wouldn't rev it over 7k as your valve train, rods and oil pump gears are weak. Without the boss springs you're also likely losing power over 7k. Were your revs 7800 before the Boss IM on the initial dyno run too?


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[05stroker]

Do you have the boss valve springs and billet oil pump gears? I didn't see it in your mods. If not, I wouldn't rev it over 7k as your valve train, rods and oil pump gears are weak. Without the boss springs you're also likely losing power over 7k. Were your revs 7800 before the Boss IM on the initial dyno run too?


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OMG, not 7k!

 

[Grabber Blue 5.0]

Do you have the boss valve springs and billet oil pump gears? I didn't see it in your mods. If not, I wouldn't rev it over 7k as your valve train, rods and oil pump gears are weak. Without the boss springs you're also likely losing power over 7k.

Mine shifts at 7600 as does many others without any problems.

 

[Gremlin85]

So you only gained 3HP from going with a Boss IM?

No, he only gained 3hp on the same dyno on a different day with different weather.

Everyone keeps missing that the worry here is that it's 3hp from STOCK. That first pull was STOCK TUNE and now it's a few bolt-ons and a tune. And not just one tune, I tried 3 different tunes. This pull gave the best results.

As far as data logs, I'll get it up ASAP. I know that on the road as well as the dyno the actual spark was what is commanded. Starts at about 20 degrees around 3k RPM and tops out at 27 degrees at 6k RPM and up.

RPM redline is 7800 but we only pulled to about 7500 RPM on the dyno.

AFR at wide open throttle is 11.9. Very consistantly as well. That's using the wideband in car. Dyno wideband at tail-pipe was about 12.1.

Load readings at 3-4k RPM was 1.01 and held until about 4800RPM where it drops slightly. By 7600 RPM the load reading is about .92.

MAF airflow is about 46 G/M by 7500 RPM.

Everything there is adding up to what I would have expected to be about 420 RWHP.

I do not have Boss valve springs or the billet oil pump. I do plan to get both as soon as I go FI but not until after I figure all this out first.

The power curve looks fine, just low according to the dyno sheet.

Again, I am not "racing the dyno". I am using it as the tool it is. I am comparing where I starter to where I am now. I do know it's on different days but that is why we have correction factors. According to a couple, the correction factors are useless as well? Even on the same dyno? I don't know, I'm just making sure my car isn't having a serious issue. If this is what it is and everything checks out, then so be it. It just threw a red flag for me.


Thanks for all the input.

 

[SSPSTANGBANGER]

Man with the tq loss I would put a stock IM back on that thing and retune it. I bet it runs faster on stock IM with your combo based on looking at the dyno sheets of the two setups.

 

[SSPSTANGBANGER]

Mine shifts at 7600 as does many others without any problems.

+1 stock springs here and I shift 7,810 with Cams and CJ IM

 

[Gremlin85]

Man with the tq loss I would put a stock IM back on that thing and retune it. I bet it runs faster on stock IM with your combo based on looking at the dyno sheets of the two setups.

Once I put a Paxton on, it won't matter lol.

 

[Redline727]

OP just to make sure I got all the facts right from your first post. You submitted the car bone stock, no mods, no tune, made 368? You then added long tubes and x-pipe and intake still NO tune and made 383? Both of these pulls were SAE corrected on the same dyno? As long as those pulls weren't done on different extreme weather days the correction will negate weather as an issue. So as long as you didn't dyno one day when it was like 30 degrees where the dyno was and the other like 105 and humid the correction is doing it's job so you can make an accurate comparison. Then later you added a boss IM and changed intake. YOU tuned yourself and made a net gain of 3hp to 386 over a stock tune with LT's and Xpipe? You then loaded a few different email tunes you had and all netted less power than you on your tune. You than returned to stock tune and went down to 350ish. Is this all correct?
If so this is what I would do. First definitely load your tune that you did and made the best power and also looked the safest. I am not surprised the stock tune on a boss IM and long tubes and X lost a ton of power. I can't imagine that manifold likes the stock tune at all. Then research the dyno you used. Mustang dyno's do not work like a Dynojet. Look it up steady state vs. Inertia dynos. They are both great dyno's but operate differently. Make sure that dyno is setup properly. Which I'm sure the owner operator knows what he has and can assure it is. But from my understanding steady state dynos can add load to the wheels much differently than an inertia dyno does. And think that factor can actually be changed and used as a drivability tuning tool by the operator. You really shouldn't say one is better than the other but people and tuners have their preferences. That's why I wouldn't compare any numbers to yours corrected or not if it was on a inertia dyno or dynapak and you used a steady state. They all do as intended but work differently.

That's why I stick with my previous recommendation in saying as long as you will compare future pulls to the past don't change dynos.

Once all the dyno settings are confirmed. I would change your spark plugs. Check your tire pressures and do a mechanical inspection of car and make sure everything looks good especially items that that could be effected by resistance. Do another couple pulls with your tune and see where your at. Stop for the day and find one of the great well known tuners in our community and reach out to one for a live on dyno remote tune session. I recommend this just to take yourself out of the equation. And see where another tuner gets you. Whatever you make after that I say it is what it is. As long as the engine looks and runs good and nothing is found on a mechanical inspection. Don't do your pulls on the day as the remote tune though. Let the car be fresh for the remote tune. I would even through is another set of plugs for that just for safe measure and change the oil.

 

[Gremlin85]

OP just to make sure I got all the facts right from your first post. You submitted the car bone stock, no mods, no tune, made 368? You then added long tubes and x-pipe and intake still NO tune and made 383? Both of these pulls were SAE corrected on the same dyno? As long as those pulls weren't done on different extreme weather days the correction will negate weather as an issue. So as long as you didn't dyno one day when it was like 30 degrees where the dyno was and the other like 105 and humid the correction is doing it's job so you can make an accurate comparison. Then later you added a boss IM and changed intake. YOU tuned yourself and made a net gain of 3hp to 386 over a stock tune with LT's and Xpipe? You then loaded a few different email tunes you had and all netted less power than you on your tune. You than returned to stock tune and went down to 350ish. Is this all correct?
If so this is what I would do. First definitely load your tune that you did and made the best power and also looked the safest. I am not surprised the stock tune on a boss IM and long tubes and X lost a ton of power. I can't imagine that manifold likes the stock tune at all. Then research the dyno you used. Mustang dyno's do not work like a Dynojet. Look it up steady state vs. Inertia dynos. They are both great dyno's but operate differently. Make sure that dyno is setup properly. Which I'm sure the owner operator knows what he has and can assure it is. But from my understanding steady state dynos add load to the rear wheels much differently than an inertia dyno and that factor can actually be changed and used as a drivability tuning tool. Especially on an all wheel drive vehicle. You really shouldn't day one you're is better than the other but people and tuners have their preferences. That's why I wouldn't compare my numbers to yours corrected our not because I was on a inertia dyno and you used a steady state. They both do as intended but work differently.

That's why I stick with my previous recommendation in saying as long add you will compare future pulls to the past don't change dynos.

Once all the dyno settings are confirmed. I would change your spark plugs. Check your tire pressures and do a mechanical inspection of car and make sure everything looks good. Do another couple pulls with your tune and see where your at. Stop for the day and find one if the great well known tuners in our community and reach out to one for a live on dyno remote tune session. I recommend this just to take yourself out of the equation. And see where another tuner gets you. Whatever you make after that I say it is what it is. As long as the looks and runs good and nothing is found on a mechanical inspection. Don't do your pulls on the day as the remote tune though. Let the car be fresh for the remote tune. I would even through is another set of plugs for that just for safe measure.

Pretty much except the there was no intake on the 383 pull. That was just LT's and catless X-pipe on stock tune.

I then added an airaid intake, boss intake manifold and tune for the 386 for a net gain of 3 hp all SAE corrected numbers compared.

it was the same AWD dyno - Mustang Dyno at Enhanced Street Performance. The operator assured me that nothing has been changed on the dyno (no calibrations or the like) and even used the loaded info from my last pull to properly load the dyno and compare.

I like your idea of plugs and inspection. I will be logging this afternoon to verify how the car is running and will ispect physical parts later tonight.

Plugs will be changed and properly gapped no matter what.

I feel the car is maxed out on the tune I have. Timing is up there and the AFR is leaner than every tuner out there is willing to run. I have so many tables changed to properly account for my mods. There is no cat over-temp protection anymore so I will always get commanded Lambda. Knock Sensors were not touched except to be more aggressive in adding or removing timing if needed. No KR is ever detected though. It actually ADDS 1/2 a degree sometimes. My Cam timing is pretty close to what a lot of tuners run except mine is a little more aggressive.

I've narrowed down that it's not the tune. It's the car or the dyno.

I will continue looking into my car as the culprit before I go to another dyno and get suggestions from local tuners. I don't think they can improve upon my tune. Iv'e got it pretty squared up.

If anyone has HP Tuners I'll be more than happy to send my tune for review.


Thanks

 

[UltraKla$$ic]

sub'd. I certainly would like to know the reason for such a small gain between all the setups and tunes.

 

[cyclerick]

My MT tremec car has never been on a dyno but tuned on the road in 4th gear (1:00). To give you an example of the impact of higher temp on HP and MPH. My morning run at a 1/2 mile speed event on an unprepped airport runway with my Paxton with TQ booster (3.15 pulley running at 10 lbs boost) running 17 degrees timing ran 150mph with a 10mph headwind. By my 3rd run in the mid afternoon when the temp was up by 20F, my mph dropped to 145 under similar headwind conditions. You will love the Paxton.


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[Gremlin85]

My MT tremec car has never been on a dyno but tuned on the road in 4th gear (1:00). To give you an example of the impact of higher temp on HP and MPH. My morning run at a 1/2 mile speed event on an unprepped airport runway with my Paxton with TQ booster (3.15 pulley running at 10 lbs boost) running 17 degrees timing ran 150mph with a 10mph headwind. By my 3rd run in the mid afternoon when the temp was up by 20F, my mph dropped to 145 under similar headwind conditions. You will love the Paxton.


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I'm excited for a Paxton, but I feel comparing HP loss from heat between a boosted car and an NA car is not apples to apples. Your heat soak has a more drastic effect on a boost car than it does on an NA car from personal experience and what I've known.

I feel there is an issue with either my car or the dyno at this point. When I compared 3 different tunes from 3 different tuners all low and then flashing back to stock and that being so low, I've concluded the above mentioned.

Still working on a reason and solution.

 

[BruceH]

Don't let the "take it to the track" guys get to you. In their world the drag strip is where they determine if a part is helping or not. If you aren't a track rat then the dyno is where you test. Just because you have a Mustang doesn't mean that only track numbers are important. Unless of course you are a track rat. There are plenty of members who like something more reliable than the "butt dyno" to evaluate modifications.

I'm excited for a Paxton, but I feel comparing HP loss from heat between a boosted car and an NA car is not apples to apples. Your heat soak has a more drastic effect on a boost car than it does on an NA car from personal experience and what I've known.

I feel there is an issue with either my car or the dyno at this point. When I compared 3 different tunes from 3 different tuners all low and then flashing back to stock and that being so low, I've concluded the above mentioned.

Still working on a reason and solution.

 

[kdanner]

Don't let the "take it to the track" guys get to you. In their world the drag strip is where they determine if a part is helping or not. If you aren't a track rat then the dyno is where you test. Just because you have a Mustang doesn't mean that only track numbers are important. Unless of course you are a track rat. There are plenty of members who like something more reliable than the "butt dyno" to evaluate modifications.

And many like something more reliable than a chassis dyno. Isn't the goal to actually make the car faster rather than to print a higher number on a dyno sheet?

 

[BruceH]

And many like something more reliable than a chassis dyno. Isn't the goal to actually make the car faster rather than to print a higher number on a dyno sheet?

I understand. Everyone has different reasons for what they do. There are people who chase dyno numbers just like there are people who chase quarter mile times.

I don't chase either but the numbers are of interest to me.

 

[CPRsm]

Why ignore a tool's reading? A track can have just as many variables, if not more than a dyno. Prep, weather, driver, etc.

 

[kdanner]

Why ignore a tool's reading? A track can have just as many variables, if not more than a dyno. Prep, weather, driver, etc.

That particular tool doesn't necessarily prove the car is any faster, nor slower, and I know that you know this. It doesn't have to be a track, it could be a v-box. Something that actually measures the car's performance.