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pristic

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Member #: 1774
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Sydney AUS

9th Jul, 2007 at 10:55:01am

Howdy,

Trying to work this out.
Whats the difference between running lower boost and higher compression or running higher boost and lower compression

Eg/ 8:1 Compression and 12-14psi
or
9:1 Compression and 6-8psi

These are just numbers plucked out of thin air, but trying to make the point.

Cheers,
Peter.

1132cc Turbo ~120 bananas ATW - Fun Fun Fun


Jimster
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455bhp per ton
12 sec 1/4 mile road legal mini

Sunny Bridgend, South Wales

9th Jul, 2007 at 11:17:41am

usually with a lower CR your off boost performace is a lower. So a less drivable. All depends what you want to do with the car.

Team Racing

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Bat

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Bermingum

9th Jul, 2007 at 06:43:57pm

Hi,
If your looking at road use, you should be able to run 10psi on the standard 9.4:1, with an intercooler, all properly setup *wink*
Higher compressioon will give you a nicer drive off boost, better fuel economy and the turbo will spool up earlier.
Higher compression will also limit the amount of boost you can put in. So the example above is an absolute maximum.
Also when going for higher boost (10psi+) you have to start thinking about the g/box and drops.
Cheers,
Gavin :)

Edited by Bat on 9th Jul, 2007.

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AlexF2003

5795 Posts
Member #: 80
AFRacing LTD

Newbury, Berks

9th Jul, 2007 at 07:20:24pm

as above

It depends what you want to do!

For high boost you needs to run low, but not just for the simple reason of detonation.

alex

AlexF

pristic

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Sydney AUS

10th Jul, 2007 at 04:07:54am

Thanks Fella's

Im after a daily. (to replace the 1132 N/A I currently have)
I want something that has plenty of pull. I dont really mind if its a slug under about 3000rpm... ill keep her above that *smiley*

I think ill be going for high boost... I want about 140-150hp (crank) from the 998 *wink*

Peter.

1132cc Turbo ~120 bananas ATW - Fun Fun Fun


AlexF2003

5795 Posts
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AFRacing LTD

Newbury, Berks

10th Jul, 2007 at 10:25:34am

fit a 1275 :p

AlexF

pristic

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189 Posts
Member #: 1774
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Sydney AUS

11th Jul, 2007 at 12:43:57pm

Haha, yeah, thats next... but for now its small bore glory *happy*

1132cc Turbo ~120 bananas ATW - Fun Fun Fun

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