Galant GSX CR?

[Jesh]

I'm sure the answer is somewhere in the forums but I didn't have any luck finding it. Anyways, I have a '91 Galant GSX that has been my parts car till recently. I have since decided to fix it up and get her running! My question is this, what is the compression ratio of the 4g63 in naturally aspirated form?

 

[IncorpoRatedX]

9.0:1

 

^truth.

In America anyhow.

 

[cheekychimp]

Wow that's really low. I would have thought it would have been higher than that.

 

[Jesh]

Hmmm... that is much lower than I thought it would be, I figured around 10:1.

 

[fuel]

jap spec is also 9.0:1 for the earlier models rated for 145hp or 10.4:1 for the later 160hp models and the 170hp AMG.

The 93-96 JDM RVR Sports Gear runs 10.5:1 pistons (on 7 bolt rods & 22mm wrist pins) and is also rated for 160hp.

 

[cheekychimp]

I thought the 145 hp cars had 9.8:1 CR.

 

[fuel]

they could well do but the documentation I have seen so far states 9.0:1 - click

I know our NZDM GTi-16V hatch had 9.5:1 CR, and historically the NZDM hatches have had higher compression ratio than the sedan counterparts - ie the GLX 4G37 sedan was 9.1:1 while the same 4G37 powered GLS hatch is 9.5:1.