GTR Forum banner
1 - 7 of 7 Posts

·
Banned
Joined
·
384 Posts
Discussion Starter · #1 ·
Did a compression test after 250 miles and shows 150 Psi apartly due to cams and 2% leakage?

These good figures for an new engine not fully run in???

Spec is:

2.7 r32 block rebored to 86.5 honed and linebored.n1 crank from rb with new front pully lightend flywheel full assemly balanced.n1 graded bearings ,cp86.5mm forged pistons with eagle h beam forged steel rods, head skimed ported and polished new valve stem seals valves reground,tomicams in 256/ex264 with cam pullys trust 1.3 mm head gasket.2x hks 2640 turbos fully rebuilt by ownes developments all polished and ported hks piping. hks fromount drag intercooler.hks hi power 409 exaust.hks mushrom filters.750 sard injectors with nismo fuel pump. hks profec b boost controller .hks f con pro gold ecu, oz giken twin plate clutch and pressure plate

Anyhelp appriciated
 

·
Registered
Joined
·
1,717 Posts
150 across all the cyliders?

Mine was 160ish across all the cyl. But it also depends on the cams, and if they are adv/ret what you'll get, can bleed of comp.
 

·
Registered
Joined
·
3,803 Posts
Getting the same value across all cylinders is more important than actual value (within reason) imho, especially as HG is non-standard and head's been skimmed etc.

How do cams come into it? (Genuine question; I'm always up for learning)
 

·
Registered
Joined
·
1,717 Posts
Getting the same value across all cylinders is more important than actual value (within reason) imho, especially as HG is non-standard and head's been skimmed etc.

How do cams come into it? (Genuine question; I'm always up for learning)
I agree with you ru', even across :thumbsup:.

Adv/Ret of the Cams changes over lap, the time that both the intake and exhaust are open at the same time, which can bleed off compression. It all depends on how it is set up, and of course the size of the cams.
 

·
Registered
Joined
·
3,803 Posts
...Adv/Ret of the Cams changes over lap, the time that both the intake and exhaust are open at the same time, which can bleed off compression. It all depends on how it is set up, and of course the size of the cams.
Obvious when you think about it; cheers for clarifying! :D
 

·
Banned
Joined
·
384 Posts
Discussion Starter · #6 ·
Ok thanks guys. Im just nervous as im not particulary up on forged engines etc and im paying alot of cash for a near perfect R33 with this engine so just wanted some good advise, thanks
 
1 - 7 of 7 Posts
Top