Low comp 2.7 turbo

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isTURBO
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Post Wed Apr 09, 2008 12:20 am

Hi Guys

I was wondering if it was possible to run a turbo on a low comp 2.7 eta bottom end with a 320/323 head?

Has it or can it be done?

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chu346
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Post Wed Apr 09, 2008 10:18 am

A 2.7 eta bottom end with a 320/323 head will be high comp.
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Post Wed Apr 09, 2008 2:43 pm

So what head wold make it a low comp or alternatively will a decomp do the trick?
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Post Wed Apr 09, 2008 4:21 pm

The head doesn't really come into it, it's the block height, crank, rods and pistons which dictate the CR.

Obviously a thicker head gasket or decomp plate will drop CR and you could have the head chambers opened up which would increase volume and also CR. ( money money money )

I would suggest you speak to Ant, go with his thoughts as he's proved he can make them and make them go fast!

Decomp plates, thicker head gaskets etc are just bodges IMO, I tried a 2.03mm HG and it blew even easier than the stock one, more sidewall for the pressure to try and move.

Build it right and it'll not bite you in the ass every 5 mins.

HTH, Mark.
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Post Wed Apr 09, 2008 5:07 pm

Would you be looking at different pistons? Or maybe some metal removed from the crown of your existing pistons (I've no idea if that would be safe or not).
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Post Wed Apr 09, 2008 5:37 pm

if you make standard 325 late pistons flat it makes for 8.0 in cr, and its tryd and tested to be very safe at around 500hp
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Post Wed Apr 09, 2008 8:02 pm

Thanks guys
The thing is I might be getting an eta 2.7 bottom end with high as well as low comp pistons etc and was hoping to use the low comp pistons and 323 head to do the turbo conversion.

Since the head doesn't affect CR I thought that with the low comp pistons I would be able to get away with it.

Its all gobble de gook at the moment.