Compression test

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Legacy777
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Compression test

Post by Legacy777 »

I did a compression test on my n/a legacy motor today since it's getting yanked out on saturday. The values I got were higher then what the book said was normal. I remember doing this before a couple years ago, and recall them being higher as well.

Anyone compression check a n/a legacy motor and have similar results? Either the book is wrong, or the gauge I have is messed up.

Here's what I got.

#1 - 205 psi
#2 - 202 psi
#3 - 195 psi
#4 - 205 psi
Josh

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scottzg
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Post by scottzg »

My car was 174 172 170 173 after i seafoamed it a while ago.
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legacy92ej22t
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Post by legacy92ej22t »

From what I've heard, it's pretty normal for compression gauges to read fairly differently from one to another. The main thing is that the cylinders are all around the same PSI.
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evolutionmovement
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Post by evolutionmovement »

Yeah, the important thing is that they're all pretty close. Of course if you get next to nothing then you have obvious problems. That sounds pretty close to what I was getting with my N/A.

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Post by entirelyturbo »

That's what I got.

We all know how carbon-happy these motors are, so I think there might be some carbon deposits stuck in various places in the combustion chamber that will only come off when you tear the motor down and clean it, no Seafoam or Italian tune-ups can get rid of it all.

You already have the EJ22T ready to go Josh???
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Legacy777
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Post by Legacy777 »

subyluvr2212 wrote:You already have the EJ22T ready to go Josh???
All the internals are done. I need to clean the intake up, and am still waiting for some parts, but I'm definitely on the down hill side of things, and it's just time from here on out.

Mid september is probably a realistic date to have it running. I'm planning to go to Japan for a week on sept 20th, and would like to have it running before I go, but we'll see.
Josh

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ballitch
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Post by ballitch »

when your values are less than 5% off from lowest to highest, i think your okay. cant ask for more than that.





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Post by gnuman »

Yes, with a compression test what you are looking for is relative equality of pressure instead of a particular number. These guages vary quite a bit from unit to unit, and I would not worry unless you have one hole that is way high or way low. Also, a compression test is all but useless on an engine that has not been run recently. It is best done on a warm engine, in fact. . .

Those numbers are just fine. In fact, what are you planning on doing with the old engine when you are done putting the 22t in? :wink:
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Legacy777
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Post by Legacy777 »

The test was done right after driving around for about 5 miles. So I think the test is good.

Not sure what I'm going to do with the engine. May sell it.....I really don't have any use for it
Josh

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Post by entirelyturbo »

If I had the money (and if shipping wouldn't be a total bitch) I'd probably buy your old motor.
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skid542
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Post by skid542 »

Just out of curiousity... approximately how much would be shipping to VA?
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Legacy777
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Post by Legacy777 »

No idea
Josh

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skid542
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Post by skid542 »

Word
Lee

93' SS, 5mt swapped, 182k, not stock...
96' N/A OBW 5sp, 212k, Couple mods... RIP
99' N/A OBW, 4eat, mostly stock.
Legacy777
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Post by Legacy777 »

After I get the new motor in, and things straightened out, I'll make up my mind what I'm going to do with it. If I sell it, I'll let ya know. It will most likely be sold as just the long block.
Josh

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1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

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skid542
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Post by skid542 »

Cool, I'm currently in the market for a good long block so I don't know if I'll still be looking by the time you get things settled but you definately treated me right with those sweet rear brakes and I'd rather buy a block from someone I trust than a JY.
Lee

93' SS, 5mt swapped, 182k, not stock...
96' N/A OBW 5sp, 212k, Couple mods... RIP
99' N/A OBW, 4eat, mostly stock.
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Post by Psychoreo »

skid542 wrote:Cool, I'm currently in the market for a good long block so I don't know if I'll still be looking by the time you get things settled but you definately treated me right with those sweet rear brakes and I'd rather buy a block from someone I trust than a JY.
any chance youre looking for a 1.8 long block?
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skid542
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Post by skid542 »

Thanks Psychoreo but I am definately wanting a 2.2 NA so I don't have to change ecus, sensors, etc.
Lee

93' SS, 5mt swapped, 182k, not stock...
96' N/A OBW 5sp, 212k, Couple mods... RIP
99' N/A OBW, 4eat, mostly stock.
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