Lowering Compression
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Lowering Compression
Havent been on here as much in recent months. Was layed off for nine months and didn't have steady income so things had to sideline. Anyway now I am back working and am looking into some projects I had put off indefinitely while I was unemployed. I just got my .3006 all sorted out and shooting well. I have an 85 mr2 I am working on. Its a cheap project. BUt anyway let me get to the point. I have been kicking around the idea of lowering the compression on my 22re using a thicker head gasket and doing some combustion chamber relief work. I would get the gasket for LCE and do the work myself. Any ideas on whether this is a good way to do it. Ideally pistons would be the way to go but the motor is not worn out enough to do that. Only has maybe 5k on it. LCE says it is definitely doable, just wanted to get others opinions. When the time comes I will start a thread showing the progress etc. I can do it for about $300 bucks including a turbo stage 3 cam.
#3
ok, obviously disregard yada21 lol... a thicker gasket will lower the compression but be more prone to blowing out, do you have arp studs? i wouldnt use a thicker gasket to lower compression on a FI motor, just my 2 cents
#4
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i think the combo of the gasket and combustion chamber relief you would be good to go, just make sure you do each cylinder equal, a piece of plexiglass with a hole drilled in it and a cc measuring beaker, test the cc volume of each cylinder as you go to ensure they are all the same. lay the glass over the head, block side, and fill the chamber through the hole and see how many cc's it takes to fill.
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I guess I should have stated that I have a turbo and sds etc. I talked with the guys at LCE and they said it would be ok, but I like to get opinions/advice from as many sources as possible before I do anything anymore. It has been done before with success on other engines but not all engines are created equal. I am not too worried just want to do my research. I do have arp head studs. I have a build up thread on here somewhere with my sds install and new manifold etc.
Last edited by saitotiktmdog; 09-07-2010 at 03:15 PM.
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I disregarded him before I even finished reading his post hahah
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#8
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I'd go with some dished pistons. Leaves some room to turn up the boost. Also if you're worried about detonation....methanol injection helped me with the MACH1
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You have a turbo? Or TURBO BLOCK?
And what is sds? EDIT: Never mind...
If you've got a 9.3:1 RE BLOCK, then you can decompress it by either using RTE pistons, or an RTE head, OR BOTH.
But that will give you 7.5:1 c/r.
And what is sds? EDIT: Never mind...
If you've got a 9.3:1 RE BLOCK, then you can decompress it by either using RTE pistons, or an RTE head, OR BOTH.
But that will give you 7.5:1 c/r.
Last edited by tried4x2signN; 09-07-2010 at 03:18 PM.
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I have a turbo yes. It was not originally a turbo engine and was just he normal 22re. SDS is a stand alone engine management system.
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delete
EDIT: Well then your compression's too high...
EDIT: Well then your compression's too high...
Last edited by tried4x2signN; 09-07-2010 at 03:21 PM.
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The plan is not to do pistons. There are essentially four ways to lower compression. 1 pistons. 2 increasing the combustion chamber in the head. 3 thicker head gasket. 4 or some combination of the other three. since I already have a good motor with low miles I am not going with option 1.
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#14
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Well thicker head gaskets plus boost on flat tops pistons is not a good idea.
Boosted cars need a great head gasket. I ran cometics on the Mach1 with 8.5:1 on 10 psi.
How many psi you seeing?
Meth injection works very well for cheap.
Here is what happened to 3 of my Mach1's pistons becuase I had high compression on the stock motor.....leaned it out and ate ring lands of 3 pistons.
Boosted cars need a great head gasket. I ran cometics on the Mach1 with 8.5:1 on 10 psi.
How many psi you seeing?
Meth injection works very well for cheap.
Here is what happened to 3 of my Mach1's pistons becuase I had high compression on the stock motor.....leaned it out and ate ring lands of 3 pistons.
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I'd take a good look at the RTE head. Marlin or Ted or somebody stated the swirl inducer pretty much kill a RE's top end.
It's not totally gone on a RTE head, but it looks more like a 20R than a RE.
Either pistons or head should put you in the 8-8.5 c/r territory.
I've been thinking this too, as a way to get power out of the limited 22RTE.
It's not totally gone on a RTE head, but it looks more like a 20R than a RE.
Either pistons or head should put you in the 8-8.5 c/r territory.
I've been thinking this too, as a way to get power out of the limited 22RTE.
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22re pistons are not flat top pistons. They do have a bit of a dish to them. You can get great headgaskets from LC Engineering who as far as I am concerned are the best source for tech and info regarding turbo 22re or 22re. period. I talked with them and they have seen it done before. I hadn't really thought about getting a turbo head though. Thats a good Idea tried4x2signN as long as I could find one that was not totally trashed or not $$$$$$. I do have an intercooler.
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hmmm... All an RET head is, is one that's been plunge bored out by a big wide drill bit...
And I'm pretty sure I've heard of machine shops being able to do it...
If you find a RTE head, take a straightedge with you... Make sure it's not drastically warped, and been milled to death.
Ppl do ask STUPID prices for them though... They seem to think a Turbo 22R's a big deal... Obviously they've never owned one...
$400
http://nashville.craigslist.org/pts/1868819215.html
$1,000
http://nashville.craigslist.org/pts/1933562488.html
And I'm pretty sure I've heard of machine shops being able to do it...
If you find a RTE head, take a straightedge with you... Make sure it's not drastically warped, and been milled to death.
Ppl do ask STUPID prices for them though... They seem to think a Turbo 22R's a big deal... Obviously they've never owned one...
$400
http://nashville.craigslist.org/pts/1868819215.html
$1,000
http://nashville.craigslist.org/pts/1933562488.html
Last edited by tried4x2signN; 09-07-2010 at 04:03 PM.
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I am still in the preliminary stages. I have been kicking this around for some time now. May have to wait until I get a house with a garage which may be a while. Doesn't hurt to start planning early though.