Today I went to KTR Performance and finally put my car on the dyno and I was not happy with the results at all. I currently am running an EVO stage 4GT. The dyno machine is a Dyno Dynamics which is a 4 wheel drive dyno. We did 4 dyno pulls and the best results were:

430HP
490TQ

I told KTR that my numbers should at least be in the 500s at the wheels and he agreed saying that a chipped turbo on there same machine put down 389HP....in fact while I was there they put down 360Hp on a Supercharged C4S.....

They checked my car for boost leaks and it had no boost leaks at all...my car ran at max 21lbs of boost. I will post my dyno graphs tomorrow and Air-flow ratio graphs.

Please give me some feedback on these numbers as they are very discouraging. Thanks

 

A chipped turbo should yield more than 389hp ... maybe their dyno is messed up or they are doing something wrong? I've seen stock turbos put out close to 389 at the wheels.

 

John,

Those numbers definitely dont look right for a Stage IV. There's gotta be something else going on thats keeping the full power from coming on.

Please keep us updated on your results. You'll get to the bottom of it soon man!

 

John - remeber that their dyno is 15% below the one Todd uses ( so divide by 0.85 to get your 'corrected numbers ' - also they use 2WD dyno so loss is less than AWD)...your numbers are sketchy though...here are two links to my runs
Fabspeed + stock program - http://www.ktrperformance.com/servic...96tt_stock.htm
Fabspeed + IA600 (GIAC level 4) - http://www.ktrperformance.com/servic..._996tt_mod.htm

Notice that even though the HP difference is not as much as I expected, the TQ difference is HUGE - might be dyno related so no worries...
Also, the speed limit on that dyno might have affected your results

 

I would try another dyno first.

 

The dyno pull had to be in third gear becuase they have a limit on their dyno, they tried 4th gear but it wouldn't work correct. The car was completey checked over during the dyno for boost problems etc....Nothing showed up.

Also I spoke with Franz the manager who conducted the DYNO pulls and he said that the numbers I had are down 20% compared to the Mustang or Dyno Jet Dyno machines.

I still feel that for the money it was not a big increase over the original stage 4 that I had

I will make an appointment for another DYNO pull on a rear wheel dyno next week.

 

no offense John but 4GT is only supposed to be 40 ponies more than 4...did you get the headers or no? Also, what octane is your program for and what wre you running? How long have you had it? These programs need at least 100 miles for the ECU to 're-learn'...Best of luck and I am sure Todd or whoever you bought it from will help you out...

 

The 4Gt has been installed for about 5 months and I do have the headers also as well as GT2 intercoolers. I was running 93 octane. I am going to take it to NEDYNO next week and see what happens on that machine.

 

I am not sure of your past experiences w/ dynos in general but all dyno resultrs have to be taken w/ a grain of salt so to speak. There was an article last month in one of my car mags about just this issue. Dinan was dynoing a M5 and the results were all over the place. It was tested over 3 days and the varience in # 's was crazy. On day one it was only 350 at the wheels, day 2 was an increase in almost 75 Hp ! and day 3 it went down 50 Hp. Dinan said that that todays P-Cars, M-Cars, AMG etc.. are simply outsmarting the dynos. He had to put a $7K specially built fan to blow on the front radiator to get his advertised figures. So dont get to upset over this, I think your car may just be outthinking the dyno at this point.

 

I know a bunch of guys who call KTR's dyno the "Heartbreaker".

 

Stephen, what octane fuel is needed for stage IV GT to produce 640 HP...100?

 

I thought I would chime in here. I believe there was a post from someone last week about how his car was making substantially less power than he thought is should for a Stage IV. Rather that get to the bottom of it, I think he said he upgraded to the Stage IVGT. The interesting thing is that he said he would be happy if he made 500hp at the wheels with the IVGT which is 100 less power at the wheels than is quoted on the website for the IVGT. For the money and upgrades, I guess I am surprised that he would settle for 100 less horsepower than was quoted.

Now I look at this thread and it appears that the numbers are extremely low as well and this is for a IVGT package. This is quoted on the websites as making 640hp or 600+hp to the wheels. One would think that this number is quoted for 93 Octane. Yet, I see a post from a tuner saying that 537hp at the engine (not wheels) is normal for the IVGT package on pump gas. Again, on the website it quotes over 740hp at the engine for this package. Interestingly, the Stage IV kits and below are quoted using 91 and 93 Octane on difference sites and the dynos show cars making 500+hp to the wheels. Something doesn't add up unless the IVGT pacakge is only meant for 100 Octane applications in order for it to make more power than the regular Stage IV.

A 200hp difference from the quoted gains and acutal gains seems a little large. Even if the quoted numbers were using 100 Octane (which it doesn't state) than the pump gas numbers should only be maybe 50hp less which is still about 150hp short.

Perhaps some clarification from the tuners on the packages and acutal horsepower numbers would be helpful at this point.

Based on the weight and tranny ratios of the 996TT, a stock Turbo vs. a Stage IVGT with the numbers quoted should yield about a 10-12mph (130mph-132mph) difference in the 1/4 mile, especially with the great launch from AWD ours cars exhibit).

Just my $.02.

 

my guess is wheel slippage on the dyno. those numbers are way too low

 

02TurboX50,

That was me on the post regarding the Dyno and my original Stage 4 (GIAC). My car dynoed at 476HP rwhp, that is with stock k24, but I was running the FVD exhaust without Cats (Check Engine light error).

Car was running rich (so they say)..........Now (KPV) is running the same GIAC stage 4 with Cats and he dynoed at 503 rwhp. That alone displays about a 27hp difference. That could mean a great deal of possibilities.....ie....Dynoed incorrectly, My check engine light code , his car just runs better........who really knows??????

So I upgraded to the Stage 4 GT and replaced my exhaust for the Fabspeed with 100 cell cats, I have not Dynoed yet, but my car is twice as fast as before and runs a great deal better. I feel the difference off the line.

I am going to Dyno my car in the next few weeks and I will post. Steve from Imagine Auto stated to me that I would be at about 520 rwhp give or take.

THE PROOF IS IN THE DYNO!

 

Sounds like it could be a combination of things. Different brand dynos have different results. Dynoing in a lower gear also produces lowere numbers - dyno's expect you to be in 4th gear with a 1:1 ratio. Was it a load dyno or inertia dyno like a dynojet? The 21lbs of boost you hit, is that they same as you make on the street or do you make more? The lower gear can throw off the calculations and result in lower load which means less boost. Was there any wheel or clutch slippage occuring? Did the dyno have a wideband O2 sensor and if so what was the AFR? Perhaps the tune could be off and it's running too rich or too lean.