Outer Limits 4x4 Board

hey guys need to kno the compression ratio on a 94 feroza hd 1.6 efi motor, as im ordering a billet or reground camshaft from camtech here in sydney in the next few weeks. the billet cam requires a motor compression ratio of 9:1 - how close is the ferozas ratio??
if the head needs to be shaved to reach this ratio does anyone kno of a shop or someone in sydney who could do it for me??
any info that could be supplied would be greatly appreciated. thanks.

9.5:1 is the stock Roza compression ratio... so if you're worried about 0.5 you would have to decrease it instead.

A thicker head gasket could help you.. if you dont want to change pistons.. but for only that small amount i wouldnt really worry...

Its probably lost compression over the years to be close enough to 9:1

thanks for that dude. but wat i meant is if u look at camtechcams.com.au it says for stage 3 cams u need 9:1 compression ratio. not that my toy has lost that 0.5 over time.

I had a look... and a higher ratio is what you want anyways.. so 9.5:1 would be spot on for the stage 3 cam mate. Which needs 9:1 as u said.

If you do 4wding.. is that the best option for you?? You're moving your useable power way up in the range.. so more revs are needed.
And idle will also suffer with a stage 3.

Also, are they going to change valve springs and rockers when you put the cam in? Springs at least need to be done.
While your getting it done (because the motor is apart lol).. I would shave the head a touch anyways (~30 thou).. to gain a little compression and to clean up any imperfections in the head surface.
They can also re-do valve sleeves for you when changing the springs.

This all helps.. because your motor will rev past where it ever has.. it all needs to be in good shape to start with... or u may have problems.

Good luck mate.
(I've also had bad reports about reground cams... get the new billet one for sure)

thanks for the update bro. it all helps me big time as im organising to do the work in the up coming weeks.

HotFourOk wrote: While your getting it done (because the motor is apart lol).. I would shave the head a touch anyways (~30 thou).. to gain a little compression and to clean up any imperfections in the head surface.
They can also re-do valve sleeves for you when changing the springs.

Good luck mate.

Our feroza has enough trouble running on PLUP with std compression.... a very common problem from what I understand

Upping the comp past 9.5 wouldn't it start to get VERY fussy about fuel, and wouldn't that sh!t you severely when you can only get lowish octane normal ULP out bush/ beach/ country

Yeah i would recommend nothing but 98 rated unleaded even an octane additive..
Just be near a city.. coz yeh 98 or even 95 rated fuels are harder to get out in the sticks

If it is a problem, you could looks at upgrading the fuel delivery system such as fuel pump to a higher volume one, larger injectors etc.. Also a better ignition system such as MSD could be utilised.

-Mick- wrote:Our feroza has enough trouble running on PLUP with std compression.... a very common problem from what I understand

Yep, mine's the same- 98 octane and standard timing or else I get pinging in hot weather. I wouldn't recommend increasing the compression either.