6 speed manual, 3.31 gears it put down 358.14 and 334 torque drove there gave it 20 minute cool down.. It was extremly hot (96 in the shop) and humid in Florida today. Tuner said would be good for another 10-15 hp with cooler weather. This is SAE corrected on a dyno jet.

 

You sure you fully disabled traction control and advancetrac?

 

Ya, those seem low.

 

Yes for sure- funny thing is the dyno was acting up and everytime we tried it , the dyno would shut down. Only made 2 clean pulls. I think the JPC car dyno 350? didnt it?

 

Yea the JPC car did 350rwhp. Do we know if the JPC dyno is a Mustang dyno.

And 358rwhp is a little low but not bad. Evo got 369rwhp, private owner got 375rwhp, another private owner got 372rwhp.

I really hope 365-375rwhp is the norm. If so ford nailed it out the park.

 

Thing is on my first run we just disabled tc and not at and got the same results.

 

With 3.31's I take it the pull was in 4th, not 5th?

 

Yes the pull was made in 4th. Would the heat be the negative factor as the tuner stated. He is a top notch guy in this field.

 

I can't say for sure but the tuner said he turned it off.

 

Usually SAE correction factors account for that but yes if the car itself was hot on the dyno it could have had an effect along with the weather.

How many miles on are on the car?

 

Your best bet is to hit the track and see what kind of mph you get.

Some dyno's can read high and some can read low.

 

The car has 840 miles, the tuner said it was reading low due to the heat and was actually impressed with the car.. All the other cars dyno'd were I believe from up north? The tuner also said that the dyno was acting up because of a sensor on the rollers? I will take it to the track in the coming weeks. And oh yeah Im pretty sure the car was hot- i drove 40 minutes with only a 20 minute cool down

 

If he thinks the dyno was acting up because of a sensor than I wouldn't trust the numbers at all. wait till they get the dyno fixed and go back.

 

The other thing to remember is that Evo's dyno is set to read very favorably to the high side so using it as a comparison is misleading. And of course, their numbers came in 5th gear so again the numbers will be off from one run in 4th gear.

358 rwhp in 4th gear in higher heat sounds pretty decent.

 

Your car wasn't hot from the drive over there. I bet if you datalogged during the trip(if a tool were available), that the registered IAT's would be no more than +5 over ambient while cruising.

BTW - do mustangs have electric fans?

358 is a fine number, nothing to be worried about. And I wouldn't worry about the heat within the shop. The dynojet SAE correction factors are amazingly accurate. I dyno'd my car at the same dyno, once in the heat of summer with a CF of 1.04, and once in cooler weather with a CF of 0.97, and the peak numbers were identical.

Now, if the dude said there was a sensor problem, then all bets are off.

 

correction factors do not take pcm pulling timing or iat's. dyno it first thing in the morning after the dew burns off. do it in 5th and let the speed limiter take it off.

 

The negative factor here is that you used 4th and not 5th for the pull. Because 5th is the 1:1 ratio in this transmission, there is less mechanical loss. In all transmissions, the 1:1 ratio is a direct connection between the input and output shaft. Any time you go through a reduction gear, you get a certain % of loss from friction. I'd say your numbers look to be in the ballpark considering it was run in 4th. With your car having the 3.31 ratio, it may actually not be able to run all the way up in 5th because of the speed limiter @ 155.

 

[QUOTE=JScottGT;5875365]The negative factor here is that you used 4th and not 5th for the pull. Because 5th is the 1:1 ratio in this transmission, there is less mechanical loss. In all transmissions, the 1:1 ratio is a direct connection between the input and output shaft. Any time you go through a reduction gear, you get a certain % of loss from friction. I'd say your numbers look to be in the ballpark considering it was run in 4th. With your car having the 3.31 ratio, it may actually not be able to run all the way up in 5th because of the speed limiter @ 155.[/QUOTE]

You would be correct,we did try it in 5th and the limiter kicked in.

 

That's what I would have prefered but instead only had time to do it around 2pm-

 

Remember every dyno will be different, I think your numbers are fine. Chassis dyno's are just a tuning tool..that's it.

Dave