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Horsepower gains on a Phase 2 Frankenmotor
Posted 26 April 2018 - 11:36 AM
Posted 26 April 2018 - 03:05 PM
The dome volume is from another site, but even aftermarket upgraded pistons range from -16 to -23 so its all I can go off of.
The quench for the Cometic gasket is 0.030. I called them.
Why use 50cc combustion chamber? EJ22E single port P1 heads are only 41CC.
remember this is a EJ253 (NOT 25D) with phase 1 EJ22E single port heads.
Edited by iluvdrt, 26 April 2018 - 03:26 PM.
Posted 26 April 2018 - 03:56 PM
Posted 26 April 2018 - 04:10 PM
If I use all the same data as before with a 8CC piston dish the compression drops to 8.1
If I use the data you suggested in your first post with my original data than the compression is 7.49
Posted 26 April 2018 - 04:12 PM
Forged Weisco stock pistons are -16 for the Piston dish. If I plug that number in using my original data than my ratio is 10.5:1
JE pistons are also -16.5
Edited by iluvdrt, 26 April 2018 - 04:15 PM.
Posted 26 April 2018 - 04:18 PM
If I type in the bone stock numbers for a complete 253 using a +8 piston dome it says the compression is 7.49. I don't think that dome volume is right Bratman. EJ253 is 9.5-10:1
If I use all stock data for a 253 with a -12 dome its 9.25 which is way more realistic. -16 piston (which is what replacement pistons are) is 9.7:1. and that is with stock 253 heads and 0.026 quench. That's pretty realistic as well.
Edited by iluvdrt, 26 April 2018 - 04:21 PM.
Posted 26 April 2018 - 04:44 PM
Those are aftermarket turbo compression pistons from JE, and the 16cc pistons sound more like ej25d at 9.7:1.
Edited by 86BRATMAN, 26 April 2018 - 04:49 PM.
Posted 26 April 2018 - 05:31 PM
So with the 22E heads what are you coming up with? Obviously I keep punching in the wrong numbers lol
Thanks for the help
Posted 26 April 2018 - 05:39 PM
11.88 using your chart with 41CC heads and a piston dish of 8. If that's the case, guess Ill have to tune it.
Posted 26 April 2018 - 09:23 PM
Posted 26 April 2018 - 09:51 PM
160 thou would wreck the quench. 6 thou plus the gasket would be in the ballpark for quench. You're going to find the compression much too high as I said though.
The aftermarket pistons WILL NOT WORK as they are pin located for 257 rods. They will sit way over the deck with an NA rod length.
Edited by GeneralDisorder, 26 April 2018 - 09:54 PM.
Posted 26 April 2018 - 10:18 PM
Ill put new gaskets on it and save it for my sons 05 impreza OBS.
Oh, checked when I got home and its a EJ251 but that doesn't make a difference. Still too high.
Edited by iluvdrt, 26 April 2018 - 10:20 PM.
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