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help

By help,
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help Apprentice

help

Posted
Posted

Heys guys I own a 96 gts-t with an Rb26 transplant with the following mods:

Garret gt35R –700 horse and custom manifold, turbosmart ex-gate 42m

Wisco forgies

Shot peened and linished rods, arp bolts

Heads ported (JHH)

Tomei Cam gears

Halteck ek6-Halteck boost controller

Sard 700’s and Boshe o44

The car has made 386 horse (280 rkw) at 18 pound with the above set-up. From the quick research I have done the hks 2530’ s flow about 350 horse each as with the T517’s so our flow ratings turbo wise are similar 700 horse. After seeing what you guys are making I am left scratching my head as to what is wrong with my set-up. From the graph’s I have seen there is a 30 to 50 kilowatt difference….

My question is what the heck have I done wrong, and is there a big difference between states (I am in queensland) between dyno’s. Most of you guys who have seen or know of RNS11Z set-up and he made 420ish horsepower (I know it was a RB25) with a t88 and still wasn’t close to you guys, so what up.

Maybe my horsepower/kilowatt conversion is way off….any ideas? Also sydney kid what is you're formula for working out spool rates.

Sydneykid Grand Master

Sydneykid

Posted
Posted
What is wrong with my set-up. From the graph’s I have seen there is a 30 to 50 kilowatt difference….

My question is what the heck have I done wrong..........

Also sydney kid what is you're formula for working out spool rates.

Hi help. let's start with dynos, the most popular is Dyno Dynamics with Shoot Out Mode software. If you are not using the same, then the comparisons are difficult to say the least.

386 rwhp is 288 rwkw using the usual "divide by 1.34" method.

I don't have a "formula" for working out spool rates, I just use experience on what we have seen in the real world. I can extrapolate that accross different engines and engine capacities. It is not perfect though.

As for what's wrong, let's start with exhaust, you didn't mention it? Intercooler? Pipework? Also I have a rule of thumb that says over 300 rwkw = upgraded camshafts, have you done them?

Without a graph of boost and A/F ratios, I am stuggling to suggest much else.

help Apprentice

help

Posted
  • Author
Posted

Sorry intercooler is a hks item all intercooler piping is hpc coated. As for exhaust it is an apexi gt item. I read a post about exhaust choking big horsepower car I think it was by "steve" so the thought did cross my mind was going to put the car on the dyno and drop the pipes to test the theory.

No I haven't done the cameshafts would rather spend the money on a three litre bottom end to be honest. Do they make that much difference for the expense.

RNS11Z Experienced

RNS11Z

Posted
Posted

Cams make a huge difference. Thats were i was losing most of my power. If your still using matty's dyno and making 380rwhp on his dyno, thats about 460 on other dyno's. His dyno is a fair wack out. It could also be your ecu that is holding you back due to no one being able to tune it.

DoughBoy Veteran

DoughBoy

Posted
Posted

I think your motor is being choked by the standard cams. No matter how much boost you run, the cams are going to dictate how much air is able to flow into and out of the engine (ok, that's pretty simplified, but that's the gist). You're going to need cams with a 3 liter bottom end anyway, so don't think of it as money wasted.

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