What gains?(C14NZ)

[icko]

Hi All,

What power gains should i expect from an 1.8 SPI (C18NZ) TB and injector, an 1.6 SPI (C16NZ) inlet and de-cat?

Would the 1.6 inlet fit my head straight away?

My engine is 1.4 SPI (C14NZ)

Thanks a lot!!!

P.S. Would it make any difference if I install a 1.4 MPI (C14SE) cam also?

[johnny27]

a 1800 injector would flood your engine, use your 1400 one, i imagine you'll not see decent bhp gains, but your engine will probaly be alot more driveable in low revs and so, maybe 4bhp more.

[johnny27]

and you would benefit from the mpi cam, a 1600mpi one may be beter the the 1400mpi

[Stuart]

the 1400 carb cam is the "best" to use iirc

[Adam]

Ye, the 1600 inlet will fit straight on the 1400 head.

[icko]

Thank you all

[icko]

Also, what gains (if any) could i expect form the C14SE cam only?

[johnny27]

abit of useful advice is try your hardest to get a 1600 manifold without the EGR valve. You can block of the egr hole with a plate and silicone, but thats not the problem. I fitted the same mods your suggesting, but got a egr equiped manifold, i blocked it off fine.
But its a real pain in the ass to get the bottom middle 2 studs of the manifold into the head, as there is no space in the manifold in between the middle branches because of the EGR. Its hard to even get the studs started never mind fully tightened to stop any air leaks.
Also get your self a brand new intake manifold gasket. BTW i fitted this to a corsa, maybe the nova is different as i said there was no spaces or no room underneath the manifold to squase your hand and your socket in.

[alistairolsen]

a mate of mine saw in the region of 18hp from a gsi cam (sr one is better tho), four branch manifold decat and full exhuast on a 1.2, he later added the inlet anifol and 1800tb and the difference was noticeable.

Im seeing in the region of 30hp from a c14nz with an mpi head, sr cam, four branch manifold, 1300sr manifold, 1800tb.

Aragorns astra made 75hp at a rr day with the std manifold and throttle plate, but an sr cam, no cat and a gsi ehaust.

id reckon if you fit a decent exhaust, no cat, 1400sr cam and the inlet suggested you will see about 80hp:D

[Adam]

14se cam isn't as good as a GTE cam.
Still better than 1400SPi tho.

[alistairolsen]

the problem with the std camshaft it that it allows torque to drop rapidly after about 4k rpm. since any tuned engine will generally make peak power well above the spi rev limit of 6200rpm, gaining torque here will make massive gains by comparison to most engines. On both my graph, and aragorns, out power climbs in a straight line thru the rev limit, on the std car it flattens off at 4500 and begins to die IIRC. For this reason a simple camshafts change can yeild surprising gains.

[icko]

When refering to SR are you talking about 14NV engine. Here in Bulgaria the model names are different

[alistairolsen]

yes sorry.

SR = 14nv
gsi = c16se
GTE = e16se
SRI = c14se
Spi engines are c12nz and c14nz

[icko]

Thank you

[uvcorsa]

Hi i have the c12nz engine in my 94 corsa, so do these mods still apply to my engine and what is best for it and potential power gains. Thanks

[Stuart]

see in the technical guides thread at the top of the page. the 1.2i tuning guide.