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EJ22 heads and EJ25 block.
Posted 06 December 2017 - 09:35 PM
Posted 06 December 2017 - 10:40 PM
there were EJ compression calculators via excel floating around online which might be possible to know as well.
Posted 07 December 2017 - 06:53 PM
Compression is way over 12:1 with phase one (90 to 98) heads. Not runable. Will pull timing like mad due to detonation issues and likely melt a piston.
Phase two (99 to 01) heads are the same as EJ25 heads. Compression will be basically stock.
Edited by GeneralDisorder, 07 December 2017 - 06:58 PM.
Posted 11 December 2017 - 09:44 PM
Posted 12 December 2017 - 02:16 AM
EJ20 heads in a EJ25 (both phase 2 obviously, phase 1 will mean changing the intake to suit the phase 1 heads) is the common option used. Try to get the 2003+ EJ202 heads as they flow a little better.
Posted 12 December 2017 - 06:13 PM
Posted 12 December 2017 - 07:08 PM
If you changed pistons and/or ran thicker HG, and could get it closer to 10:1, that'd be a great street ratio. Would need premium gas 24/7.
Don't pick cams at random or off a shelf. Everything from curb weight, usable powerband, gearing, cr, etc. need to be factored for optimum benefits + driver expectations (i.e. talk with the rep and go custom grind). If it was a V8, I'd say favor a torque cam and sacrifice redline for excellent acceleration; for a 4 banger, you'll want more rpm, which needs decent valvesprings, etc. and might be an obese dog for DD unless you like winding it out constantly.
Posted 13 December 2017 - 10:19 PM
You have to run 25D pistons AND thick head gaskets with those phase one heads. Compression will still be 10.6:1
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