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2.2-2.5 hybrid build up.


tailgatewagon
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ok so my imp with the swampers on it feals a little weak, dont get me wrong it will still drive 80mph and with the pp6 i have coming it should be better but i need more even if i do the dr 5speed swap. so these are my plans, anyone ever done anything like it.

 

2.5 block...

2.2 dual port heads.

obx header.

delta cams

and a 50shot of nos.

 

anyway any input would help.. thanks

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High compression + nitrous = trouble.

 

The headgaskets are pretty close. The coolant holes through the gaskets are a bit different.

 

I've been told the deck height is the same, so you can use the 2.2l manifolds on it.

 

It's pretty much plug and play. I'm getting a 2.5 to put in my loyale now that I've FUBARed my nice rebuilt EJ22. I was considering doing a hybrid, but I also wonder if I can afford the premium gas all the time. But the torque...mmmmm...

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I am also in the midst of this shortblock swap.

 

I was thinking turbo until all the warnings.

 

I now am just using headers (have them thanks Jules)

 

and a custom exhaust.

 

My questions center around which idlers to use.

 

I also want to retain the EJ25 intake, as it appears

the intake runners are larger.

 

Any links / info appreciated.

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skip, i would use ej22 idlers as the blocks are the same as for the placement of the idlers. also use the ej22 tenshioner you can unbolt the peace that the tenshioner bolts to and replace the junk 2.5 one with the ej22 one. the ej25 ones are junk as im shure you know... not shure about the intake but ill ask a local shop that dos 2-5 ej22 swaps into ej25 cars every week..

 

 

as for the closed deck thing, or headgasket isures im not worried i will be using a phase 2 ej25 and they have external leaks not internal ones like the phase 1 motors did even if i have to do headgaskets every 50k thats fine also if the compresion is high enough to require the use of 90+ octane then im just going to go with water/meth injection......

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Use which ever idlers are newest with the least amount of miles. TGW is correct that the tensioner can be replaced with the EJ22 style one. The 2.5 tensioner will be OK if it isn't leaking at the shaft.

 

As far as using a 50 shot for offroading, not a good idea in my opinion. Extra pressure that the deck doesn't need. The hybrid will give you more than ample torque. The D/R will be a nice addition for hill climbs. I would try to find a F/T unit though.

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legacycentral.org and nabisco both have a fair bit of info on this hybrid, search for "high compression frankenstien" or something close to that...

 

copression depends on which blocks and heads you use, I believe the

phase 1 ej25 + phase 1 ej22 heads (dual port exhaust) ~11.2/1 comp

phase 1 ej25 + phase 2 ej22 heads (single port exhaust) ~10.5/1 comp

and the phase 2 ej25 will make higher compression... Matt Monson said something to the effect of the hp/tq gains are more from displacement gains than compression gains...

 

you will most likely need 91 octane

 

Skip: Intakes must remain matched to heads, so 2.2 intake on 2.2 heads and 2.5 intake on 2.5 heads...

 

Headgaskets line up, just not as much openings for water jackets on the 2.5 gaskets as on the 2.2's seems most people have been drilling/dremeling the gaskets to get around the issue

 

I'm getting my heads re-surfaced asap, my 2.2 is blowing smoke out the tail and oil out the maf...

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Use which ever idlers are newest with the least amount of miles. TGW is correct that the tensioner can be replaced with the EJ22 style one. The 2.5 tensioner will be OK if it isn't leaking at the shaft.

 

As far as using a 50 shot for offroading, not a good idea in my opinion. Extra pressure that the deck doesn't need. The hybrid will give you more than ample torque. The D/R will be a nice addition for hill climbs. I would try to find a F/T unit though.

 

i agree some what with the 50 shot being a bad idea.. it will be the last option....

 

as for the f/t box, i want to be able to buy tires in 2's not 4's i would rather have the 2wd,4wd,4wdlow box vs the ft dr5speed,

as for idlers just buy new ones... there cheep. like 26 bucks each if you have connections.(if you need some hit me up) but yea like qman said use the newist ones...

 

any input on the water injection?? after reading about it i think it may be the ticket even if i dont need premium.....

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cool deal i may end up going that route instead of turbo for the brat in the future, does the stock ecu do alright with it, i had a high comp honda motor that ran like pure crap on a stock ecu

 

not changing the compression at all (or much....anyway), just the displacement.

 

 

AND, the stock EJ22e ECU is capable of compensating for quite a bit. especially if coupled with higher flow injectors.

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it runs the same as an ej22e, rock solid idle, great throttle response etc.

it would run pretty rich with bigger injectors unless you do some stuff and yes, it is much higher compression. stock ej22 is mid 9's. when you add displacement to a given combustion chamber, the compression ratio will go up.

main strong points of the motor are great torque, cheap to build, use all ej22 wiring/sensors, great on gas(3300lb awd wagon gets 27mpg combined, heavy foot), dead nuts reliable. one of these motors with delta cams dynoed 135whp in an impreza which is probably over 200 at the crank. it would be super fun in a light car.

 

but mine is a heavy car and Im looking for more ooomph so Im doing the reverse now and building an ej22 with ej25 heads. with HY35W for motivation.

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my understanding is that because the bore is larger, and the pistons are different the ratio is the same...but I don't exactly understand.

 

you can put slightly larger injectors on and have the ecu compensate for it. it just uses the signal from the O2 sensor to determine how much fuel needs to be added, and adjusts accordingly. if the injectors are larger, it'll just reduce the voltage so the flow is the same....

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