Late Power ?

[Nee-san]

Hey guys,

I've just bought a 32 GTR and am having issues with power coming on late.

Generally it starts to become pretty hectic at 6000 - 8000 RPM but after doing some forums searches on here and asking around, i have found that this is very late given the turbos i am using (R33 N1)

Car is as follows;

4" Stainless steel exhaust including X-Force turbo dump pipes with HKS front engine pipes

5" HKS Cannon muffler

Splitfire coilpacks

APEXI Power FC

HKS 660cc injectors

HKS Fuel rail kit

Nismo fuel pump

Nismo fuel pressure regulator

Trust 4" intercooler

Trust intercooler piping kit

HKS air filter kits x2

N1 R33 turbos (steel wheels)

Arias pistons

Nismo rings

Eagle rods

Block was torque plate honed for exact clearancing

Nismo oil pump

Crankshaft x-rayed and magnafluxed

Nismo main and big end bearings

tomei 2.0 mm multi plate steel head gasket with oil restrictor kit

ARP head studs

Head fully serviced, valves guides and seats replaced

Light port and polish done as head flows very well from standard

Throttle bodies and inlet plenum port matched perfectly to cylinder head

HKS cams - 265 inlet and 272 exhaust, 10mm lift

Engine has just been run in.

car is making 431hp@17psi hope to make a bit more at some point.

I've been consistantly told that it is my cam selection that is causing this, so i thought i'de ask around on here to see what you guys think.

Cheers, Mitch.

[R31Nismoid]

Well your cam choice isn't exactly great - factory would be better with a set of cam gears.

Do you have a graph with boost vs rpm?

R33 N1 turbos are... average. I'm surprised you've chosen them on a motor with a reasonable amount $$ behind it.

They shouldn't be "that" laggy though either way. They should be on around the 4000-4500rpm marker if im recalling results correctly.

They are basically the same response as a HKS 2530 (or Garrett -5), but without the same peak power figures possible which would be around 4000rpm for things to start.

Are the cams dialled in correctly?

What boost control are you using?

[Nee-san]

Hey R31Nismoid,

Thank's for the speedy reply, unfortunately i don't have a Boost Vs. RPM graph.

The turbos came with the car although i do intend to change them in the future, looking for 400kw (could you suggest some perhaps?)

Currently the car does not have cam gears, and the boost is controlled by a bleed valve;although i do have an early HKS EVC that needs to be set up along with the scramble boost controller.

Cheers, Mitch.

[R31Nismoid]

Just hold the turbo wastegates shit - wire them.

If boost comes up earlier, then the drama lies with your boost control plain and simply.

If not then things like cam's/cam gears being dialled in etc would be the next logical thing to inspect

As for 400RWKW - Garrett -5's. PLENTY of info around, please search for the details on them.

[Nee-san]

Sweet as, thanks for the help

been reading through the rb26 turbo compare thread.

Cheers, Mitch.

[paulr33]

yeah as ash said check the basics

the engine has that much done to it, it could be a dozen things

check base timing, check tune, check cam gears