Matching cylinder head chambers to the larger EJ257 bore???
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From: South Wales, Scoobless, Type R is gone!
Having read this comment from Andy F on the EJ257 GB thread:
"Regards matching cylinder head chambers to the larger bore, although not absolutely necessary, this is recommended for optimum results. I can supply details of what is required for a DIY operation or optionally it can be done here if required for £50/head."
I'm looking to get a set of STI5 heads done locally for a EJ257 conversion, but need to know what size to get them opened out to. Do i go for 99.5mm or slightly bigger or smaller?????
"Regards matching cylinder head chambers to the larger bore, although not absolutely necessary, this is recommended for optimum results. I can supply details of what is required for a DIY operation or optionally it can be done here if required for £50/head."
I'm looking to get a set of STI5 heads done locally for a EJ257 conversion, but need to know what size to get them opened out to. Do i go for 99.5mm or slightly bigger or smaller?????
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From: Enginetuner.co.uk Plymouth Dyno Dynamics RR Engine machining and building EcuTek SimTek mapping
We always check them out for compression ratio and machine accordingly.
There are a number of variations of Impreza chamber size and you need to check them all out when doing a decent 2.5 conversion. There is also the possibility of using different thickness gaskets.
There are a number of options, ranging from AndyF's good offer, we'll do the same in the South of course! RCM use a CNC programmed special squish set up, or Ric Wood also does the business with fully flowed and chambered heads.
There are a number of variations of Impreza chamber size and you need to check them all out when doing a decent 2.5 conversion. There is also the possibility of using different thickness gaskets.
There are a number of options, ranging from AndyF's good offer, we'll do the same in the South of course! RCM use a CNC programmed special squish set up, or Ric Wood also does the business with fully flowed and chambered heads.
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