Can anyone tell me the compression ratio on a 93 WRX import and also the compression ratio on a 95 uk turbo wagon.

 

Possibly 8.0 : 1 and 8.5 : 1 respectively but not definately. The 95 Wagon may be 8.0 : 1 only.

 

Ok thanks for the reply, Im in the proccess of fitting a 95 uk wagon engine in to my WRX because one or both of the head joints is gone and just wondered what the comp ratio was on the new lump.

The plan is to totally strip the WRX lump and fit steel and forged internals so it will be going back in. The WRX has a stainless up pipe, is it worth porting the headers and fitting the stainless up pipe to the new engine. I have both engines sitting on the garage floor so this would be the time to do it if Im going to, also will I need new gaskets or will the old ones probably be ok, getting new ones isnt a problem I just want to know so that the job goes as quickly as possible. Both cars have a full decated stainless from the turbo back.

 

if your gunna rebuild a scooby engine, nothing is more important than the bearings matey, and then once done make sure the fueling is mapped well...

 

Yeh Im going to do the full monty, anything that can be uprated will be. I was also going to get the crank tuftrided and balanced with flywheel, clutch and pulleys fitted. It has an APS billet flywheel which was fitted with a clutch only a few months ago. Ill probably get another one though because its down as an APS high torque clutch on the reciept from the tuner who fitted it but its not, its an EXEDY. This was done before I bought the car and a bit naughty but Im not going to name the tuner.

 

Harvey, would you have a recommendation as to the right compression i should be looking at for a high output 'built' 2.5 running 98ron? Not to familiar with cr's on a scoob and the only knowledge i have is of mini's so 13:1 might be a bit out....

 

Only slightly out there Doug PMSL!

Russell

 

Evander : If you are referring to header gaskets/up-pipe/turbo/header to head gaskets, nine times out of ten these are Ok to reuse with a LITTLE exhaust paste.
Proper porting of the headers will make good gains. This is a fair bit of work and you need to get right inside the cast headers. Refit heat shields or better still exhaust wrap after removing and dressing the lugs.
About your stainless up-pipe, I cannot comment without seeing it and measuring various dimensions BUT a LOT of people loose power and spool by fitting an inappropriate up-pipe.

Hi Guys and best wishes for 2007. Lang may yer lum reek!!!

I have no first hand experince of experimenting on CR on a 2.5 litre. Matt Clark has built several very health 2.5s also Scoobymania so I would listen to what their thoughts would be. My thoughts are that a lot will depend on what turbo, boost level and heads you want to run. My educated starting point would be 8.0:1 or even 7.8:1 but that would depend on other variables and be influenced by what was said by RCMS and Mike Tuckwood.
13.0:1 Well yes, you could try that and dispense with the turbo, up pipe, headers etc. Think of the weight saving!!! Let me know how you get on.
FYI. Last years WRC cars were running something like 12 : 1 C.R but that has no relevance on what you are trying to do.