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88HatchMonster

EJ22 Swap into EA81 w/ 4spd d/r

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Is it possible to do an EJ22 swap in to an EA81 utilizing the EA81 4spd d/r tranny rather than converting to an EA82 5spd d/r? If it is possible, would this be a dumb idea or not?

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Hey 88 This is Jerry, yes you can do that with an adapter plate but why. The EA82 5 speed can handle more HP that the 4 speed and they bolth have the same bolt pattern on the bellhousing. A few times really getting on that 4 speed with the EJ22 you will brake that 4 speed. I am not saying you can't brake the 5 speed anything can be broken, but you will be much happer with the 5 speed. Thanks Jerry

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but doesnt the 4 speed have better crawling gear ratios? I have an 86 gl that has the 5 speed D/R, I dont think that i would like the 4 speed, unless you want to make the ultimate subaru-rock-crawler. and what year car will this be going into? i think the 1st Gen. cars have narrower frame rails from what ive heard.

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ehhh this isn't a first gen car though..... EA81s were gen 2s.....

 

Yes the gearing in a 4-speed d/r has a slightly lower first gear BUT it cannot handle the power from the EJ22. This is why people are going with the EA82 d/r 5-speed plus it has better gears for the highway as well...

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According to Austin, it seems like ej22 conversion into older subarus doesn't necessarly need d/r tranny. He didn't really specify the reason why, but it would be best to ask him and find out. If that is true, you don't have to spend time and money making an adapter plate or spend money on buying one.

Dan

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ok, confused ones...

the 5 speed has a better crawl ration than the 4 speed dr.

 

the 4 speed dr should be able to handle the same amount of power. as far as my research showed. the gears are the same width, and made out of presumably the same metal 4 or 5 speed.

 

i have a 4 speed hooked to a 6 cylinder. i have floored it quite a bit now, and it shifts smoother than any 5 speed i have ever touched.

 

you dont NEED a dual range, but if your goin offroadin, with bigger tires, dual range is the only option.

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I just crunched some numbers... Common factors were 3.9 final drive gear ratio and 28.9 (235/75R15) tire size. These were used in the crawl ratio calculation. Differenciating factors were tranny gear ratio and low range gear ratio. http://www.s-series.org/htm/calc/crawlratio.htm

 

5spd Dual Range Crawl Ratio: 22.01

 

4spd Dual Range Crawl Ratio: 20.3

 

It's rather confusing just looking at tranny gear ratios. The key is that the 5spd has a Low Range gear ratio of 1.592 while the 4spd Low Range gear ratio is 1.462 That minor difference in Low Range more than makes up for the minor difference in tranny gear ratios.

 

Tranny info was derived from http://www.ultimatesubaru.org/forum/showthread.php?t=14547&page=2&highlight=5spd+gear+ratio

I can not vouch for it's accuracy as JWX copied it from another source so who knows where the data came from. I know JWX wouldnt lie about it or anything but its tough to say where the info came from. Looking at all the info in that thread there is some minor variances in gear ratios based on where the data came from (or what application and/or year).

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I think mine came from a FSM, but I could be wrong its been awhile since I copied and pasted it.

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I'm still waiting on some more documentation about the swap.. primarily the wiring issues.

 

Whens John or Austin gonna chime in with a writeup?

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I originally asked the question because I am contemplating an EJ22 swap into my lifted hatch. I just wanted to weigh all of the options. If I do the swap I will get a 5 spd d/r now that I know it has a slightly better crawl ratio. Might as well if I'm going to do all of the rest of the work involved in the EJ-EA swap.

 

I've got my eye on 4 early legacy's in backyards all along my commute to work through northern NY and VT! I just gotta save $200-$250 or so and get up the nerve to knock on some doors...

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