Phase II Frankenmotor - doable?

[wotdsm]

I really want to squeeze more power out of my 99 Forester and I want to do it cheap (go figure)... I was thinking of bolting a set of Phase 1 EJ22 heads on to my Phase 2 EJ251

 

I know P1 EJ22 heads will bolt up to my P2 EJ25 block. But then I'd have to get the P1 intake mani/sensors/accessories to play nice with the P2 ECU. If I splice the pigtails that differ between P1 sensors and the P2 wire harness, use my P2 cam and crank pulleys, and if I source an EJ18 throttle body (has an IACV) it should theoretically work, right? Has anyone ever put a P1 setup where a P2 engine once was? Looking for input on this setup. 

Thanks

Edited August 3, 2016 by wotdsm

[MilesFox]

I have put a phase 2 ej25 into a 96 LOB 5mt 22e. no IAC to. But i have enough parts ro do it the other way and put a phase 1 manifold in a phase 2 car. haven't done it tho. in theory it should work.

[wotdsm]

The only speed bump I forsee is the fact that my current setup is MAP as opposed to MAF. But it seems that EJ18 throttle bodies have a MAP sensor on them so we may be okay there.

 

**EDIT** Scratch that, I guess I'm not seeing a MAP sensor on EJ18 throttle bodies. I could always tee a map sensor into an existing vacuum line if I end up going this route. 

Edited August 4, 2016 by wotdsm

[matt167]

It will be a mess, but there is an easier way.. Pretty sure the crankshaft/ camshaft actually trigger the same, so that's taken care of.. The Map sensor on an EJ251 that goes into the manifold is a MAP/ IAT combo sensor, so if you change sensors, then you also need an IAT sensor with the same range to keep the ECU happy.. The sensors you pin in, HAVE to match the ranges the ECU needs even if it can function out of range. The easier way is to make manifold adapter runners. There is/ was a company in Europe making them but it would be easy enough with both gasket patterns. The runner below the injector will help atomization also. Also, you will be choking your EJ25. The PI EJ22 heads are horrible flowing heads.. You could do the same with EJ25D heads/ intake and it will bump compression same. You could also boost the EJ25D heads since the castings are the same as EJ20K turbo heads. They just didn't drill the oil and coolant connections

[wotdsm]

Thanks for the input! I'll look into those adapters. 

 

I was under the impression that P1 EJ22E heads mated to P2 EJ251 bumps the compression ratio to about 11.5:1 increasing horsepower to around 165hp... 

[idosubaru]

I think i'd just do something simple like delta cams, get 200 hundred pounds of weight out of the car, adjust wheel/tire sizes for higher top end or better acceleration.

you'd probably end up with more gains that way than what you're talking about.

 

i'd make a distinction - trying to bump power out of an NA engine is futile process.  track times will still be slow and barely noticeable from what you have now.  but if you've got gobs of time and want a project and to learn - then yeah, you'll enjoy the process!

 

I've done porting, polishing, gasket matching, lightweight pulleys, aftermarket cams, modify transmission shifting, playing with heads, removing the A/C compressors/pulleys....and i've never noticed a difference...or very small differences.  the actual 0-60 and quantitative times would be very little difference.

 

but i learned a ton in the process, like what to never waste my time on again now that i'm older and have very limited free time!  i have a set of 6 low compression forced induction pistons and 3 spare 6 cylinder engines if i ever need an actual performace bump.  but at this point i've gotten further away from that desire. 

[wtdash]

Thanks for the input! I'll look into those adapters. 

 

I was under the impression that P1 EJ22E heads mated to P2 EJ251 bumps the compression ratio to about 11.5:1 increasing horsepower to around 165hp... 

 

 

Yes...but this is for the P1 cars' electronics- pre-'99.

 

P1 heads require P1 intake and electronics and won't work well>>easily on a P2.

 

No offense to Matt167 but isn't the '99 EJ25D a P2 block w/the P1 EJ25D heads  from the factory?...and you'd still have the issues w/the P1 vs. P2 electronics. 

 

Also, the '99 Forester was an odd year as it had the P2 EJ253 (per Wikipedia) and a MAF but not backwards compatible w/the pre-'99 MAF ECUs.

[matt167]

As far as I know, they are a phase II block but I think that the pistons are different from the P2 SOHC engines, so the engine should still see a static compression bump..

 

The ONLY way the 25D heads would work with the '99 P2 electronics is the intake adapters

 

'99 Foz is Map/MAF EJ253 or it could be a MAP EJ251 if it was built late enough.

Edited August 14, 2016 by matt167