N/A frankenmotor question

Heads, valves, pistons, rods, crankshaft, etc...

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scuba steve
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Location: Portland, OR

N/A frankenmotor question

Post by scuba steve »

When doing the N/A EJ25 block/EJ22 heads frankenmotor, can you use the Phase 2 block??...say from a 2001???

It's for my 91 wagon. I made one b4 with with a phase 1 block, just wondering if 2 works. :-)
99 Outback Limited 30th Anniv. White/Sandstone
Riding on WRX Suspension and 17" Neon SRT4 rims
PhyrraM
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Re: N/A frankenmotor question

Post by PhyrraM »

You need to check and see if the volume in the phase 2 SOHC heads is the same. If it is close, then it all should be good.

If not you'll need to do compression ratio calcs based on your parts to see if it climbs too high or low.

I'm guessing it should be fine.
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klin7757
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Re: N/A frankenmotor question

Post by klin7757 »

I've been looking into this for my girlfriends Outback. From the numbers I have the phase II (2000+) pistons have a dish of 14.5cc while the phase I is 14cc. With a phase I head gasket (1.52mm) your compression ratio would be 10.26:1 and with a phase II gasket (.58mm) it would be 11.41:1.
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