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For whatever reason, still have a speed limiter. Could only do the select shift mode in 3rd gear because of it. On this Mustang Dyno, I hit 361 rwhp and 321 ft-lb of torque at 6600 RPMs. The tech said if he could have gone into 4th, it would have been closer to 370 rwhp.
2013 Mustang GT Kooks Headers Dyno - YouTube
 

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seems low...do you have a custom tune?
 

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Mustang dyno's read a little lower than dynojet.

The question is what was the baseline number before the headers?

It's the comparison between baseline and modded that is important.

Saw a dyno pull on a dynojet of a bone stock '14 and it was 376/349.
 

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Discussion Starter #4
seems low...do you have a custom tune?
Bama.

Mustang dyno's read a little lower than dynojet.

The question is what was the baseline number before the headers?

It's the comparison between baseline and modded that is important.

Saw a dyno pull on a dynojet of a bone stock '14 and it was 376/349.
Baseline was 321. If it hadn't been for the speed limiter being reached, we could have gone higher than 3rd gear, which would have made a little bit of a difference today. I'll get that fixed and then once I get the Ford Racing intake manifold installed, probably take it back for another dyno.
 

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low gears make low numbers... If it was in fifth, 1 to 1, your numbers would have been higher... like those that dyno with 3.31 and taller... remember... a dyno is a tool and should be used to give you the direction, amount of change and torque curve ... nothing more.
 

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Discussion Starter #6
low gears make low numbers... If it was in fifth, 1 to 1, your numbers would have been higher... like those that dyno with 3.31 and taller... remember... a dyno is a tool and should be used to give you the direction, amount of change and torque curve ... nothing more.
Very true. Regardless of the final numbers, I'm happy with the gain. I read that for the automatics, 4th gear is the closest to 1:1, whereas the manual is 5th. I'm still stuck with my stock 3.15s. I'm hoping to upgrade to 3.73s someday.
 

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Bama.



Baseline was 321. If it hadn't been for the speed limiter being reached, we could have gone higher than 3rd gear, which would have made a little bit of a difference today. I'll get that fixed and then once I get the Ford Racing intake manifold installed, probably take it back for another dyno.
So the headers alone gave you a 40 HP bump? That's pretty damn good.
 
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how is that possible when I made 387rwhp stock and now I'm at 420rwhp+ tuned on 93 octane? Mine was done at 5th gear with 3:31s manual
 

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how is that possible when I made 387rwhp stock and now I'm at 420rwhp+ tuned on 93 octane? Mine was done at 5th gear with 3:31s manual
Because of all the reasons above about dyno numbers...
 
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Because of all the reasons above about dyno numbers...
Yeah but he has headers and I don't. Performance wise, all I have is: off road h pipe, borla s type axlebacks, and a 101mm steeda cai, oh and a a tune but yeah its still extremely low numbers for him.
 

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Hang on, what's the dyno thing? If you have a LOWER gear ratio, Say 3.15 vs 3.73 the 3.15's will dyno HIGHER numbers? Or did i read the wrong?
 
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Yeah but he has headers and I don't. Performance wise, all I have is: off road h pipe, borla s type axlebacks, and a 101mm steeda cai, oh and a a tune but yeah its still extremely low numbers for him.

You have a manual trans, he has an auto. He would probably put up a better 1/4 mile time than you with those mods.

Hang on, what's the dyno thing? If you have a LOWER gear ratio, Say 3.15 vs 3.73 the 3.15's will dyno HIGHER numbers? Or did i read the wrong?

Yes that is correct. Less friction and therefore drivetrain loss with lower numerical(taller) gears. We are talking 5-10hp measured at the wheels and not a perceptible performance difference. The shorter(3.73, 4.10) gears will still feel faster.
 
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You have a manual trans, he has an auto. He would probably put up a better 1/4 mile time than you with those mods.




Yes that is correct. Less friction and therefore drivetrain loss with lower numerical(taller) gears. We are talking 5-10hp measured at the wheels and not a perceptible performance difference. The shorter(3.73, 4.10) gears will still feel faster.
Well thank god I don't go to the track and it's just a mega fun daily. If i was about timeslips I woulda gotten an old 5.0 and built the crap out of it with an automatic trans.
 

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low gears make low numbers... If it was in fifth, 1 to 1, your numbers would have been higher... like those that dyno with 3.31 and taller... remember... a dyno is a tool and should be used to give you the direction, amount of change and torque curve ... nothing more.
Wrong-
I just got the following explanation from another forum and called the shop and they verified the info given to me when I dyno'd my car
“the reason for the dyno in the 1:1 gear ratio is due to the Dynojet. Dynojet mathematically creates a horsepower number based on mass (which is the known weight of the rollers) and accleration (how fast the car is accelerating the known weight).

F=ma

From force (F), we can calculate horsepower.

Dyno the car in 2nd gear, and acceleration (a) goes way up, causing force (F) to go way up.

So by dynoing the car in the gear closest to the 1:1 gear ratio, we eliminate any acceleration advantage or disadvantage caused by the transmission, which gives us unskewed whp numbers (even though Dynojet has a fudge factor in there which makes them skewed anyways and read high).

As for other dynos out there (i.e. Mustang and Dyno Dynamics) - they use a load cell to measure roll force (the amount of force the tire is placing on the roller). Based on roll force and the radius arm going to the load cell, we get roll torque. Based on roll torque and roll speed, we can get vehicle horsepower. Vehicle horsepower and vehicle RPM gives vehicle torque. It doesn't matter what gear you run in on load cell style dynos as they are measuring force, not acceleration. Force does not change from gear to gear.”
 
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Actually JohnRichard is correct, dynos measure work and not just force. Dynoing in 5th gear will put about 10-15hp MORE to the wheels than a 4th gear pull and has been confirmed multiple times over several different dyno types. The Dynojet is by far the most popular kind of dyno and I'm sure there is an exception to this. Now for an automatic the numbers are already skewed due to the torque converter and the amount of slip called for by the tune.
 

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Discussion Starter #16
how is that possible when I made 387rwhp stock and now I'm at 420rwhp+ tuned on 93 octane? Mine was done at 5th gear with 3:31s manual
What kind of dyno did you use? If it was a DynoJet, that immediately explains higher numbers with very mild mods, along with it being a manual. With those mods, I highly doubt you were on a Mustang Dyno.

My baseline of 321 rwhp was a mixture of the dyno type, the car being an automatic, the tech not taking traction control off, and him leaving it in drive versus using select shift. If I'm not mistaken, most baselines for manuals on a Mustang Dyno are closer to 340 rwhp.

With the latest run on a Mustang Dyno, the car was in 3rd gear using select shift (4th topped out at about 120 mph; AM is sending me a dyno tune), and traction control was turned off. I was using the 91 race tune, which combined with the headers, got me an additional 40 rwhp in 3rd gear at 106 mph. According to the tech, I would have gained an additional 5-7 rwhp if we could have run it in 4th. That puts my realistic gain at 45-47 rwhp (366-368 rwhp total), which I think is pretty damn good for just adding headers and a tune.

I could go out on a DynoJet right now and probably make at least 420 rwhp, but to me, it's just inflating my numbers to make it look better. As mentioned before though, the primary goal is to use the same dyno to get a baseline and then accurate gains for mods.

Have you run yours at the track? We only have an 1/8 mile track here and I'm really looking forward to getting back out there. I did one run with just exhaust and a tune; I ran an 8.53 with a crappy reaction time (probably would have been closer to 8.3 with a little work). I'm anxious to see what I run with the headers installed.
 
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What kind of dyno did you use? If it was a DynoJet, that immediately explains higher numbers with very mild mods, along with it being a manual. With those mods, I highly doubt you were on a Mustang Dyno.

My baseline of 321 rwhp was a mixture of the dyno type, the car being an automatic, the tech not taking traction control off, and him leaving it in drive versus using select shift. If I'm not mistaken, most baselines for manuals on a Mustang Dyno are closer to 340 rwhp.

With the latest run on a Mustang Dyno, the car was in 3rd gear using select shift (4th topped out at about 120 mph; AM is sending me a dyno tune), and traction control was turned off. I was using the 91 race tune, which combined with the headers, got me an additional 40 rwhp in 3rd gear at 106 mph. According to the tech, I would have gained an additional 5-7 rwhp if we could have run it in 4th. That puts my realistic gain at 45-47 rwhp (366-368 rwhp total), which I think is pretty damn good for just adding headers and a tune.

I could go out on a DynoJet right now and probably make at least 420 rwhp, but to me, it's just inflating my numbers to make it look better. As mentioned before though, the primary goal is to use the same dyno to get a baseline and then accurate gains for mods.

Have you run yours at the track? We only have an 1/8 mile track here and I'm really looking forward to getting back out there. I did one run with just exhaust and a tune; I ran an 8.53 with a crappy reaction time (probably would have been closer to 8.3 with a little work). I'm anxious to see what I run with the headers installed.
Not a mustang dyno, they are running a $40 for three pulls special all the time so I may head their way this or next week and see since ive had my tune tinkered with a bit.

Nope never been to the track but I have used the track apps. I went once and I didnt have a helmet ( didn't know my car was too fast to go down without one ) so I just watched.
 

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Wrong-
I just got the following explanation from another forum and called the shop and they verified the info given to me when I dyno'd my car
“the reason for the dyno in the 1:1 gear ratio is due to the Dynojet. Dynojet mathematically creates a horsepower number based on mass (which is the known weight of the rollers) and accleration (how fast the car is accelerating the known weight).

F=ma

From force (F), we can calculate horsepower.

Dyno the car in 2nd gear, and acceleration (a) goes way up, causing force (F) to go way up.

So by dynoing the car in the gear closest to the 1:1 gear ratio, we eliminate any acceleration advantage or disadvantage caused by the transmission, which gives us unskewed whp numbers (even though Dynojet has a fudge factor in there which makes them skewed anyways and read high).

As for other dynos out there (i.e. Mustang and Dyno Dynamics) - they use a load cell to measure roll force (the amount of force the tire is placing on the roller). Based on roll force and the radius arm going to the load cell, we get roll torque. Based on roll torque and roll speed, we can get vehicle horsepower. Vehicle horsepower and vehicle RPM gives vehicle torque. It doesn't matter what gear you run in on load cell style dynos as they are measuring force, not acceleration. Force does not change from gear to gear.”
Ok trainwreck.gif
 
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