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ea81 maximum compression?


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i have to rebuild my motor so turbo pistons are on my 'to do' list

what i likely to be my weak link ie bottom end,head gasket........?

 

cheers for any help

Why would you use turbo pistons? they are the lowest compression of all the pistons available

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i want to know the max comp the motor can stand so i know how much boost i can stuff in

BTW what compression do the aeroengine 81s run?

i ate a piston last time, hence the turbo slugs

i'll post pic if i can get my camera to talk to my computer...dumba*s technolgy

Why would you use turbo pistons? they are the lowest compression of all the pistons available
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  • 3 years later...

First, yes I know this thread is three years old! (But I searched, like we always like people to do)

 

Having scoured through all of the old posts, I have never seen a good answer for this. What is the max compression one could expect to get on an ea81 that would be reliable, without having to go to custom pistons?

 

I am wondering if 10:5-11:5 is possible/advisable. And if so, what would be the most cost effective way to get there.

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I am wondering if 10:5-11:5 is possible/advisable. And if so, what would be the most cost effective way to get there.

 

No. In short the quench design of the heads could not withstand it. Detonation city.

 

9.0:1 would be alright - 9.5:1.... maybe 10:1 using the EA82 SPFI would likely be alright as the fuel injection can handle the ignition timeing better to allow it.

 

Anything over about 9 would require computer fuel injection to control the ignition timing or you would have to retard it so far it would be worthless to bother. Massive compression without the ability to advance the timing is worse than lower compression.

 

GD

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