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Discussion Starter · #1 ·
I know that you can get higher compression pistons to raise your compression ratio. But what else could you do. I would think that getting the heads decked down would have the same effect of using a thinner head gasket without the risks. Reason being is that I have P&P'd SVT heads in a UPS truck heading to my house. Just trying to get some discussion and new ideas going on this. Thanks.
Jake
P.S. I did search, didn't find much.
 

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getting the block decked as well would help...but this is not a strong knowledge area for me
 

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You have to keep in mind that you have a chain for the cams that has to have tension on it. If you put new chains on it then I would say that you can deck the heads probably .020-.030 without problems. That won't give you a bunch but it will give you some. Don't deck the block because your piston will get too close to the head and at high RPM can "touch" the cylinder head. That's not good at all. Don't get thinner gaskets either, not that they make any that I'm aware of, but they will have the same affect that decking the block will. Also, IF you deck the heads you need to put some modeling clay on the piston and put the head on there with the gasket, the old gasket will work, and turn the engine over so that you get a valve impression on the clay. You need a BARE min of .080 piston to valve clearance to keep the valves from hitting the pistons, Not good either. With all that considered knock your self out. Be sure to run premium 93-94 ALL the time or you will be tearing that engine down frequently for head gaskets, pistons, spark plugs and other such things that don't like detonation. Getting a chip burned for higher compression won't hurt either.

T.J.
 

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Originally posted by: CougarGT
Pop those heads onto a 3.0L block.

11.2:1 Compression :)
:banana:
 

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bring it to a competent machine shop... they can weld new material into the combustion chamber, port it clean and voila, bumped compression.....
 

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Discussion Starter · #7 ·
Thanks everybody, I do plan on putting them on a 3.0L, but I might want to have some fun before that, thats why I asked. Thanks again.

Jake
 

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Why not slap a turbo on there...it'll bump compression nicely... ;)
 

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If you bump the compression on the heads now for your 2.5 that would be great for power for right now. OR You could look into SVT contour pistons. I have seen them on Ebay pretty cheap every once in a while.


If you go to put those high compresion modified 2.5 heads on the your eventual 3.0 .....then compression will be so high you may have to run race gas. Keep in mind stock 2.5 heads will bump compression by a good bit if you install them on a stock 3.0 block.
 

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Discussion Starter · #10 ·
Never thought about that GMK. Still trying to get a quote on getting some 3L valves put in and for an install. Thanks again.
Jake
 

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You can get a max of .2 CR to maybe .3 CR by milling the heads. That's it.
Remember this drastically reduces your piston to valve clearance.

You do not want to deck the block.


Your best option is a hybrid 3L or just new pistons. (For instance +1mm 2000 SVT pistons would bump you to around ~10.4)
 
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