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wolfie

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Somewhere around Swindon

13th Jul, 2005 at 11:17:46pm

what have you lot got on here when you compression test your engines

i did mine tonight and was surprised at the results not sure if being laid up has fubarred my engine

pot 4 100psi
pot 3 100psi
pot 2 100psi
pot 1 between 95 and 100 psi

i know its a low compression engine but im sure it should be better than that?

Crystal Sound Audio said:
Why wolfie...you should have your name as Fuckfaceshithead !


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Dangerous

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Swindon

13th Jul, 2005 at 11:55:01pm

13 bar on a standard 9.4:1 turbo engine.....when warm i.e. run for a couple of mins

make sure you wedge the throttle open

Edited by Dangerous on 13th Jul, 2005.


Metro turbo weekend driver,Mini turbo in the making again!



Nick
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Midlands

14th Jul, 2005 at 07:39:46am

i had 120psi +/- 2 psi across all 4 after i'd run my engine in, thats with an 8:1 CR.

all plugs out, fuel pump off and throttle wide open.

On 20th Oct, 2015 Tom Fenton said:
Well here is the news, you are not welcome here, FUCK OFF.

wil_h

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Betwix Harrogate and York

14th Jul, 2005 at 07:42:25am

Mine are around the 100psi mark.

Just having a quick thought, If you have a CR of, say, 7:1, then you are compressing the air 7 times. Assuming no losses you'd expect the pressure reading to be 7 times atmospheric.

Atmospheric is 1 bar (14.5psi) so you'd expect a 7 bar (101.5psi) reading.

Is this right?

Wil

Fastest 998 mini in the world? 13.05 1/4 mile 106mph



On 2nd Jan, 2013 fastcarl said:
the design shows a distinct lack of imagination,
talk about starting off with a clean sheet of paper, then not bothering to fucking draw on it,lol

On 20th Apr, 2012 Paul S said:
I'm mainly concerned about swirl in the runners caused by the tangential entry.


Vegard

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I pick holes in everything..

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Norway

14th Jul, 2005 at 08:17:39am

It is correct assuming that the volumetric efficiency is 100% which it VERY rarely is without forced induction.

Edited by Vegard on 17th Jul, 2005.

On 13th Jul, 2012 Ben H said:
Mine gets in the way a bit, but only when it is up. If it is down it does not cause a problem.

turbo hogster

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stowmaket suffolk

17th Jul, 2005 at 09:15:09am

you also hjave to bare in mind the overlap of the cam you are using as well. as vegard said its all to due with ve.

on big cams the actal comp is quiet low until you come onto the cam up the rev range when the VE rises considrably due to negative ramming on NA engines or when you come on boost on turbo engines

always looking for them bigger bunches of bannanas
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