Good to know.

 

N.A version is F20C1
CR ratio of 11.1:1
240hp

JDM/Euro version is F20C
CR ratio of 11.7:1 (different piston head design)
250hp.



I have also put dyno on N.A. S2k vs JDM S2k (both bone stock)
JDM version showed 8whp more on same dyno at same day.

MY03 N.A. = 205ps
MY00 JDM = 213ps


After dyno, we also had short rolling start runs and it was clear that JDM had more hp.

 

To get back to the original question.

We have done JDM engine swap about 2 years ago.
and I remember it was pretty straight forward EXCEPT...

you have to transfer VTEC oil pressure sensor from your USDM engine to JDM engine.

 

I believe there are only two types of CR 11:1 and 11.7:1. Never heard of 11.1:1


My car is Euro spec and it is 11:1. Only JDM have an 11.7:1CR and yes, the pistons are the cause of the extra CR.


[QUOTE=jwkim,Apr 19 2006, 10:03 AM]I have also put dyno on N.A. S2k vs JDM S2k (both bone stock)
JDM version showed 8whp more on same dyno at same day.

MY03 N.A. = 205ps
MY00 JDM = 213ps


After dyno, we also had short rolling start runs and it was clear that JDM had more hp.

 

oops my mistake on "euro" and CR on USDM.

F22C USDM has 11.1:1

 

I was under the impression that the F20CX (where X is 1 or 2) were 11.1:1.

 

F20 in the US is 11:1

F22 in the US has 11.1:1

 

I would think they have different head gaskets to hold the higher compression?

 

There is only a single headgasket on the F20 series of engines and I guarantee it will hold anwhere between 11 and 12:1 compression ratios just fine. Probably a whole lot more (dynamic compression from a supercharger on a stock is a lot higher than an 11.7:1 engine). The gasket would be fine with so little extra compression.

 

Then how do the JDM motors achieve the extra HP? Higher comp pistons?