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1995 EZ30 Coupe
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Discussion Starter · #83 ·
I've been tinkering with my built motor to get it ready for install, and I've discovered the heads are far too close to bolt the intake manifold on. Womp womp.
Also the heater core return pipe (ej25d) intersects the oil dipstick tube (06 WRX), and some of the bolt holes in the rear timing cover (ej25d) don't line up with the heads (90-92? ej20g). But those are easily remedied.

As far as the manifold issue, I'm guessing the timing will be off as well so need to fix that. I think my head gaskets are just way too thin, so I'll be taking some measurements and possibly ordering some .120" mls gaskets from Cometic. Here's hoping the heads weren't over decked into oblivion.

IMG_20210207_093208201.jpg
 

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Discussion Starter · #84 · (Edited)
I meant to post the previous post earlier, but oh well. I've measured the gaskets, and as near as I can figure, they're about .02". That works out to about .5mm, and supposedly the stock ej222 gaskets (which I thought these were) are .8mm.
Anyhow, a rough kinda measurement, kinda estimation tells me the heads are ROUGHLY .12" shy, and the current gaskets together are about .04", so I need to take up almost .16" with the new gaskets, or .08ish apiece. Cometic makes .08" gaskets, so I guess that's what I'm ordering. We shall see.

Edit: something wasn't sitting right, so I did some tedious remeasuring. Looks like they're off by closer to .25" all said and done. So .120" gaskets it is!
 

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2000 RSTi
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How many times have those heads been decked?! Geez
 
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Discussion Starter · #86 ·
Idk, I got them off Craigslist a couple years ago. They seem to be ok, there's a little indent that I believe is used to measure how much they've been decked. It matches some ej25d heads that I'm confident have never been decked, but I suppose that's not definitive.
Also the deck to manifold bolt hole distance appears the same. Maybe those early legacy ej20g's had thick ass head gaskets?
85885

85886
 

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Yeah the ej20g (and ej20k, ej22t, ej25d...) had the thicker 1.3mm/.051" (compressed) factory gaskets. If the legacy ej20g had even thicker ones than, say, wrx ej20g heads, I don't know.
 
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98 RS | 98 L Wagon
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That's a pretty big difference in the gasket thickness. Do you know where it's going to put your compression ratio?
 

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Discussion Starter · #89 ·
No idea. Well, I'm thinking it may be in the high 7:1's, based on some of my research. I should probably be more concerned with it than I am, but I'm my head lower CR = more boost. I'm a little concerned about the quench hight though. I don't know enough about it to make an informed decision but I've read a little, apparently it plays a sizeable role in preventing or causing detonation.
Ahhh well, I guess we'll see how it tunes. I'm into this motor for roughly $4k, and having read about 10k-15k+ builds I'm feeling pretty good about it. I've got too many ideas (and too many parts) for motor builds anyway.
 

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Definitely lower CR is safer. Go too low and it will be a major dog out of boost. High 7's is probably alright, but definitely I wouldn't go any lower (if at all possible).
 

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Is it possible that intake manifold is warped?
 

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Discussion Starter · #92 ·
I don't think anything will be more of a dog out of boost than the ol' 1.8/2.2 hybrid. Also I'm really determined to run a compound turbo setup with the GT35 pushing through a TD04. I expect it to be an interesting torque curve, and just fine for my style of driving. Idk, this whole thing is an experiment.

Manifold warpage is certainly possible, I got the manifold with the heads, and Craigslist is always a gamble. That said, she sits nice and flat, so it would have to have been decked after warpage. I tried fitting an EJ25D manifold, and it also was too wide to bolt on, but by slightly less.
 

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Discussion Starter · #94 ·
Ordered the .120" gaskets, that's compressed thickness mind you. Unfortunately Cometic is about 5 weeks out so they'll hopefully ship mid March. I guess I have time to save up for a transmission that can actually stand up to the power I want to make. With the GT35R I should be able to get 450 to the wheels pretty easily. The stock 90's N/A 5MT isn't gonna like that! Till then I've got some suspension and brake upgrades to install, gauges, modifying my piggyback with a 3Bar MAP... And it's still cold as a bitch out.
 

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Discussion Starter · #95 ·
Some THICK ASS GASKETS arrived today.
86199

86200

Juicy.
 

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Discussion Starter · #97 ·
Hoping to drop it in the next couple weeks!
 

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#32
95 Coupe, 95 Sedan & 95 Wagon
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12,590 Posts
Throw mah hat in tha rang'
Bust out that 4 piston bang'
Let all them shots rang
While my transmission sangs

(There's some motors
in
the
house)


Bro put me on the track yo!
 
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