cooperlee

Who's got them in their GT4? Are the gains noticeably recognized on the street and at the track?

My car is going in soon for the runners, new dundon gt3 exhaust set up (currently with race headers and oem pse exhaust), and dundon cobb retune. Not looking for earth shattering gains but curious to see where I will see the improvements.

SGOGT4

I was an early adopter. I really like them. Opens the car up quite notably in the upper RPM range. Stock, when you got up beyond 5k rpm, the car always seemed to get louder at a disproportionate rate compared to the rate of change in speed (felt louder than it was fast). Now the thing pulls hard straight thru red line. nice and linear along the way.

user1029

https://rennlist.com/forums/gt4/1116...l#post16143772 my protune

Reborn996

Recently added the Dundon runners with IPD intake plenum and GT3 throttle body. Had a custom tune by Shiv and hit 376hp to the wheels. This was with stock headers and exhaust!

James88

Very nice, that's like 430 at the crank.

k3|th

Very nice results. Shiv tuned my Aprilia...is there any vehicle he can’t tune? LOL!

JCviggen

+21 wheel horsepower translates to +45 at the crank now?

It would probably translate to around 410-415 engine HP on a MAHA dyno. Not actually much more than you would get with just the tune and larger throttle BUT the difference is the place where you get the extra power and area under the curve. The car will gain more performance than the peak numbers are suggesting.

The 718 GT4CS plenum/runners/throttle would see similar results, moving the power band upwards is a good thing on these engines.

cooperlee

Very nice gains. With headers and exhaust, you should easily get up to 400whp as the headers and a more free flowing exhaust should free up additional torque and hp. my car previously made 368whp with race headers and cobb tune. With the new dundon runners, gt3 exhaust, and a pro tune, Im hoping to get near 400whp as well.

SGOGT4

@Reborn... where did you do the Dyno? I'm here in the bay and have the full D4 setup. Maybe I'll stick her on there and see what she makes.

user1029

go to your local Cobb tuner and I bet you’ll get a few extra ponies and extra margin of safety with a protune

even after multiple data logs I sent to Dundon for their etune, my local Cobb tuner still made more power at every rpm and he was able to get rid of the partial throttle stumble that Dundon wasn’t able to

Ugly-Nugget

I have the Full D4 set up, I installed the headers first which was a noticeable difference from stock. I then had the rest of the D4 setup installed. I have the Black set up and the sound is very nice adding the GT3 center, there is a nice power increase after the full install. I love it and the sounds it makes is fantastic.

switchface

Nice gains up top, I just wish there wasn't such a loss at low RPMs as I daily my car.

So your local Cobb tuner has a better custom tune for Dundon's parts than Dundon does with their own Pro-tune?

user1029

yup! I’ve been modding cars for god knows how long and at the end of the day just because a company makes stellar parts doesn’t mean they can give you the optimal custom protune. Dundon’s etune was so conservative that it made like 365whp and when my tuner loaded on the actual STOCK map, the car made 371 whp. Finally he did his custom protune which netted me 385whp and the car drove way smoother around town. I have 93 octane and I think dundons more accustomed to tuning on 91 octane there

Reborn996

Tune and dyno was through Shiv so he would have to comment.

sgreer78

From Jamie
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