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Old 04-13-2010, 02:37 PM   #6
soobaviator
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Originally Posted by blkjag View Post
Thanks for the replies.

Is there a relatively inexpensive set of pistons (maybe something that's OEM on another engine) that could be used with the EJ205 block and the EJ253 heads to get the compression ratio back up to the 8.5:1 - 9:1 range?

Also, is the EJ22E block really much stronger than the EJ253?

One other question; are timing belts of different lengths required when swapping heads/blocks like this? Or, are all the crank pulleys all pretty similar (so you'd just be able to use the OEM belt for whatever heads you choose).
Drop in Wiseco's and an .027 inch MLS gasket looks like it will get you to 8.5:1, if I may revise and extend my remarks. Quench would be good to go at .043 inches. The Wiseco pistons retail for $450-$550

If you are intent on using the 253 heads and want high compression go with the 22E and the 253 heads. Stock block the compression is over 9:1 with a .051 in MLS gasket. Quench is good at .041 inches on this set-up.

It may be an even shot up to a certain power level but for a given same HP the pressures inside the 253 cylinder will be lower and it has a thinner wall. The 22E has a thicker wall but the cylinder pressures will be higher. The 205 and 22E have the same wall thickness and are open deck. The 205 works for boost to 30 psi. The limits of the 22E should be a bit less than that. The 253 was not designed for boost, especially the heads. It comes down to a calculated risk depending on your power goals.

To my mind I can imagine the 253 cylinders "walking" all over the place with every ignition event under boost so it concerns me. It may not concern you...

SOHC to DOHC the belts are different. Crank sprockets maybe they are but not sure. In any case they are interchangeable on the cranks so no problem switching to the right setup.

How much boost and what turbo?
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Last edited by soobaviator; 04-13-2010 at 04:34 PM.
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