R32 Gtr Kw @ Wheels

[GODZILLA]

I RECENTLY PUT MY CAR ON A REAR WHEEL DRIVE DYNO AND GOT 210 KW ON THE REAR WHEELS I JUST HAVE 14PSI AND KNN FILTER EVERYTHING ELSE IS PRETTY MUCH STANDARD INC EXHAUST. BUT HOW REASONABLE IS THAT IF IT WAS A 4WD DYNO IS THAT REASONABLE POWER FOR A GTR OR BELOW STANDARD. AND HOW MUCH EXTRA WOULD I GAIN IF I PUT A 3" EXHAUST FROM THE TURBOS BACK, OR WILL I HAVE TO BOOST IT BACK DOWN, I HEARD IF U PUT EXHAUST ON IT WILL BOOST UP HIGHER IS THIS TRUE. THANKS IN ADVANCED

[igor@af]

210 kw is how much you should get stock. That is around 281 hp, GT-R is "supposed" to have 276hp [280ps] so you are actually getting 5 free ones

[GODZILLA]

SO STOCK THEY ARE SUPPOSED TO HAVE 280HP ON THE WHEELS

[igor@af]

Well, they're supposed to have 280PS, which is around 276HP.

[R33]

Hi Godzilla, something do not quite add up there! Stock R32 should have about two hundred seventy six hp at the engine at stock boost ie 0.8 bar (11.5 psi). At 14 psi or 1 bar, it should have about 335 hp at the engine. That would translate to about 300 hp at the wheel. Your car recorded 283 hp at the wheel - this could mean the boost reading is not right/you are losing pressure somewhere/there is a lot of power slippage at your clutch/transmission. It could also mean that there was torque transfer to the front tires when the dyno was done (was the front drive disabled during the dyno run?)

Proper exhaust installation (means the right size) could yield about 10-15 hp especially with the aftermarket filter which you already have. Boost could also be increased but that would require remapping of thye ECU (to inject more fuel and rewrite ignition). But boost of more than 1 bar is not recommended on stock turbo.

Hope this help!

[GODZILLA]

YEH SOMETHING DOESNT SEEM RIGHT TO ME TOO.IVE GOT A BRAND NEW CLUTCH IN IT AND THE FRONT WHEELS WHERE DE-ACTICATED IVE BUMPED UP THE FUEL PRESSURE. BUT WHATS THE CONVERSION. IF STOCK IS 280HP AT ENGINE AND I GOT IT AT THE WHEELS AT ONE BAR IS THAT RIGHT. IT STILL SEEMS WRONG TO ME. OR AM I WRONG IM CONFUSED. BUT I HAVE NOTICE MORE LAG ON THE TURBOS LATELY IS THAT A HOSE, THE HOSE ON THE INTERCOOLER HAS (ON DRIVERS SIDE) ONE HOSE AND ANOTHER OVER IT THE OUTER HOSE SEEMS CRACKED BUT I DONT THINK THE INNER HOSE IS.

[igor@af]

NOTE: Hey GODZILLA, I want to ask you a favor, please stop using all caps when typing the message thanks:smoka:

[GODZILLA]

sorry

[R33]

There is no exact conversion formula from engine to wheel power. As a rule of thump, the loss is guesstimated to be between 10-15% (some say 20%). No matter what it is, I still think that the R32 should produce more than the 283 hp it is now producing at the wheel at 1 bar boost. If the hose is broken (you might be able to see it or you might hear whistling when you boost comes on), than you are losing pressure and that could cause abnormal lag.
If you increase boost from stock to 1 bar and the hp does not increase significantly (which actually they should), than it might be due to the fact that you have not remapped the ECU to provide more fuel in view of more air volume after the boost increase. Increasing the boost without increasing the fuel delivery will result in a lean fuel/air mixture - you can notice this when the engine is strugling at high rpm (coarser than normal engine sound). That could be the reason for your low hp even when the boost is 1 bar.
Bumping up the fuel pressure is not the answer to a lean mixture. You have to do it at the ECU. I would suggest that you check the air/fuel mixture. I suspect it is lean.

[GODZILLA]

yeh what you say sounds spot on. I havent remapped the ecu and i can hear the turbos whistle pretty loud. where can i take it to get remapped in sydney and what would the cost be. furthermore whats the best way of checking the hoses . i tried with wd40 but could tell. i put it on the diagnostics and found no faults.what would be the hp i should be getting. i think it is lean.
thanks heaps

[SkylineUSA]

GODZILLA,

So what was wrong with the idle? Is the car running better?

[SkylineUSA]

Did you figure out the timing marks?

[GODZILLA]

i havent figured out the the timing marks yet as for the idle changed plugs bit better but still misfires i have no @$%# idea still looking i sprayed everything whole engine bay with wd40. u should see it i can enter shows with it now. and still cant find the prob. its beginning to really shit me. its idleing about 1200 rpm dropped it down give it a week goes back up. feel like burning the thing

[R33]

The R32 GTR at 1 bar boost when properly mapped (with KN filter) should churn out at least 350 hp at the rear wheel. To remap, you need an aftermarket fuel computer such as HKS F Con V Pro or Apexi somethin' somethin'. They could cost about US 1500-1800.
Whistling could be caused by a hole in the 'cooler hoses or an imbalanced turbo (this is hard to diagnosed). I think you need a pro to advise on this or to check it out.

The cheapest way to get advice from the Oz is to join Autospeed (for A$18 for mths), you can ask question in the forum (the replies are really good from people who really know their stuffs - I'd been a member for mths and just renewed recently). Check it out at www.autospeed.com. You can even ask the editor to solve your problems!

[adamandsonja]

hi guys
i think that your hp LOSS figure is too small. I would expect much more % loss with the gtr 4wd drivetrain.
An exhaust would help your cause no end, in fact it should have been your first mod. Increasing the boost and getting in more cold air is to little avail if the thing is all choked up at the outlet side of things. My 33 R with cold air, exhaust and boost at 14.5psi would give very close to 400hp at the fly. Put on an exhaust and yours would be very close to that figure too.
adam.