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[ngrainqey]

hiya,
does anybody know any rough compression drops when using the 3.0 heads on the 2.5?
might beable to get some pretty cheap for my turbo project (can use thinner spacer plates that way too!)

thanks

[Marks DTM Calib]

Er.....let me look on my laptop as I have a spreadsheet with it all calculated

[feeutfo]

stick a 3.0 lump in it and start from there. Go on you know you want to. :-)
Breakers on here must have one. Ave it..!

[ngrainqey]

ok thanks mark!

lol i can have a 3.0 lump for 50 quid (dont ask somebody ows me money) so for another 50 pounds i can have one

im thinking of having a 3.0 to toy, rebore it and put 2.5 heads on (been looking at forged pistons today on the internet) for high compression high cubic capacity
and then maybe having a project omega and finding a suitable gearbox for it!

but atm i'm on with project turbo

[Kevin Wood]

ok thanks mark!

lol i can have a 3.0 lump for 50 quid (dont ask somebody ows me money) so for another 50 pounds i can have one

im thinking of having a 3.0 to toy, rebore it and put 2.5 heads on (been looking at forged pistons today on the internet) for high compression high cubic capacity
and then maybe having a project omega and finding a suitable gearbox for it!

but atm i'm on with project turbo

We did work out the compression with 2.5 heads on a 3.0 once. IIRC, it was in excess of 12:1, so a bit high really.

The other way round should get you down into the 9's so might be OK woith forced induction.

Kevin

[ngrainqey]

ok thanks mark!

lol i can have a 3.0 lump for 50 quid (dont ask somebody ows me money) so for another 50 pounds i can have one

im thinking of having a 3.0 to toy, rebore it and put 2.5 heads on (been looking at forged pistons today on the internet) for high compression high cubic capacity
and then maybe having a project omega and finding a suitable gearbox for it!

but atm i'm on with project turbo

We did work out the compression with 2.5 heads on a 3.0 once. IIRC, it was in excess of 12:1, so a bit high really.

The other way round should get you down into the 9's so might be OK woith forced induction.
Kevin

forced induction was exactly what i was thinking and lmao about the 12:1 comp ratio... you think reboring the 3.0 to around 3.5 would effectivly blow the gasket to smithereens at 12:1 ?
had to ask *rolls eyes*

thanks

[Kevin Wood]

forced induction was exactly what i was thinking and lmao about the 12:1 comp ratio... you think reboring the 3.0 to around 3.5 would effectivly blow the gasket to smithereens at 12:1 ?
had to ask *rolls eyes*

thanks

Reading your post again, you're looking at forged pistons. That might change things a little. Nest question is, of course, how many revs the rest of the bottom end will take.

Kevin

[ngrainqey]

forced induction was exactly what i was thinking and lmao about the 12:1 comp ratio... you think reboring the 3.0 to around 3.5 would effectivly blow the gasket to smithereens at 12:1 ?
had to ask *rolls eyes*

thanks

Reading your post again, you're looking at forged pistons. That might change things a little. Nest question is, of course, how many revs the rest of the bottom end will take.

Kevin

hiya kevin,
i'v been looking at turboing the 2.5 so it's either run it on under 6psi oor get spacers and run more boost or replace the heads or a combination and heads and spacers and run alot of boost

the 3.0 using 2.5 heads is just a stupid idea of mine- can get a 3.0 bottom end complete to fart about with including reboring it if i can find somewhere to do it and match some forged pistons to it!
i'd be getting the company to match the pistons and the bores obv lol!

thanks

[Martin_1962]

12:1 - try LPG

[ngrainqey]

12:1 - try LPG

what difference will that make martin?
run better with lpg at high compression ratios?

[Kevin Wood]

12:1 - try LPG

what difference will that make martin?
run better with lpg at high compression ratios?

Yes, LPG is much less prone to knock than petrol so you can safely run higher compression without having to use forged pistons, etc. In fact, you can gain a bit of economy by doing so.

Kevin

[ngrainqey]

ok thanks mateys