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EA81 SPFI conversion and more horsepower/torque??

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if you look at them side by side you will get it. the spfi has two holes in the heads, and manifold. the mpfi, is multi port, so theres twice as many runners. wont bolt up

no. all ea81/ea81T intakes head ports are the same. same as the ea82 carb/SPFI ports. (that's why the SPFI manifold bolts right up to the ea81 heads....

 

however the ea82T intake head ports are different.

  • 3 years later...
Just decking the heads .020 will pull the compression up to 9.12:1. Addition of the 1600 pistons should raise it even more.

 

GD

With decked heads and 1600 pistons what is the compression ratio? I had this done when i ordered my engine from CCR and never asked what the final ratio was.

1600 pistons aren't much taller than 1800. About .007" IIRC. But you might have to do a search on some of my older posts to find out for sure..... it's not a lot though. SPFI pistons are the way to get massive comp. numbers.

 

GD

1600 pistons aren't much taller than 1800. About .007" IIRC. But you might have to do a search on some of my older posts to find out for sure..... it's not a lot though. SPFI pistons are the way to get massive comp. numbers.

 

GD

Your right, reading what you told me made me remember that the guy that built my engine at CCR said something about SPI pistons. At the time i wasnt to concerned because i really needed the motor to get my car back on the road, but now im curious. He must have ment SPFI pistons. Gonna give them a call tomorrow and find out for sure. So with SPFI pistons and decked heads (ill find out how much they took off tomorrow) just assuming .020'', what do you think the compression ratio is about?

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