anyone run 6.8:1 compression?
Aug 11, 2008 | 06:41 PM
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500bhp Cosworth in making
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From: Brandon
anyone run 6.8:1 compression?
is this too low compression for a cossie, seen a set of pistons with this comp ratio just wondered if this cr is ok for 430bhp,t4,Ported head etc
Aug 11, 2008 | 06:43 PM
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From: Sunderland
Lawnsys is down at 6.9:1 on greys and T34@36psi and seems to do well
Aug 11, 2008 | 06:44 PM
Advanced PassionFord User
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From: Newcastle
6.8 is ok...........as is 7, 7.2, 7.5, 8.0, 8.5 and possibly even 9.
Aug 11, 2008 | 06:46 PM
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From: scotland
Im down there somewhere and have the fastest saf after Rod's.
Aug 11, 2008 | 06:47 PM
Thread Starter
500bhp Cosworth in making
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From: Brandon
suppose you have to make it up with loads of boost!
Aug 11, 2008 | 06:50 PM
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From: North Korea
Quote:
Originally Posted by
Roosie
suppose you have to make it up with loads of boost!
but you can, safely. lots of ignition too.
properly low, but as long as you dont fuck things up with big cams, it seems to work just fine.
Aug 11, 2008 | 06:52 PM
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From: scotland
Mines run 2 bar now and big cams and doesnt seem to be short on power!
Aug 11, 2008 | 07:10 PM
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From: Edinburgh
Danny b ran um in his old saph!
Last edited by peteh; Aug 11, 2008 at 07:13 PM .
Aug 11, 2008 | 07:15 PM
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From: North Korea
Quote:
Originally Posted by
rapidcossie
Mines run 2 bar now and big cams and doesnt seem to be short on power!
your cams arnt long duration are they?
Aug 12, 2008 | 06:16 PM
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From: LEVEN , FIFE
I went down from 7.2:1 and dont notice any change in the way the car drives off boost.
Aug 12, 2008 | 06:17 PM
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From: scotland
Quote:
Originally Posted by
Stavros
your cams arnt long duration are they?
what do you class as long?
Aug 12, 2008 | 06:21 PM
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From: North Korea
well whats your duration?
Aug 12, 2008 | 06:22 PM
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From: scotland
Aug 12, 2008 | 06:23 PM
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From: North Korea
that is quite wild actually for a turbo car, but spools well, fair play
Aug 12, 2008 | 06:25 PM
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From: scotland
Alot of things on my car are specced for top end power but we still manage to get good bottom end too, just dont ask me how?
Aug 12, 2008 | 06:29 PM
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From: LEVEN , FIFE
Where is your car making peak power now Euan think mine is 7800 ?
Aug 12, 2008 | 06:30 PM
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From: scotland
it makes about the same at 7500 as it does at 8000 now.
Aug 12, 2008 | 06:32 PM
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From: LEVEN , FIFE
Cool mine is still going up at 7800 then levels i think but still more to do on responce,think the head might be flowing too well
Last edited by NEIL A; Aug 12, 2008 at 06:33 PM .
Aug 12, 2008 | 06:34 PM
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From: scotland
Quote:
Originally Posted by
NEIL A
Cool mine is still going up near 8K i think but still more to do on responce,think the head might be flowing too well
leave it with Alan over the winter and see how how much he can squeeze out of it.
Aug 12, 2008 | 09:28 PM
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From: edinburgh
i run 6.9.1,t4 twin bd 14s at 30 psi and its a dog under 4k
Aug 12, 2008 | 09:41 PM
I've found that life I needed.. It's HERE!!
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From: fife
that could change once its been mapped col
Aug 12, 2008 | 09:44 PM
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From: edinburgh
hopefully glancy,hope the new head inlet etc make a diffrence aswell
Sep 1, 2008 | 11:55 AM
Thread Starter
500bhp Cosworth in making
Joined: May 2003
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From: Brandon
Quote:
Originally Posted by
col cos1
hopefully glancy,hope the new head inlet etc make a diffrence aswell
has it been mapped yet.
keep looking at Euans JE pistons for sale
Sep 1, 2008 | 07:05 PM
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From: edinburgh
yip its done 419@wheels on full boost at just over 3.5k im led to believe
Sep 1, 2008 | 07:41 PM
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From: Stockport, Cheshire
Quote:
Originally Posted by
Stavros
that is quite wild actually for a turbo car, but spools well, fair play
At what what lift? A std RST cam is 270 degrees at 0.1mm lift. You have to be careful when comparing figures, without the lift it's meaningless.
Sep 1, 2008 | 07:48 PM
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From: scotland
.399mm valve lift on my cams.
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anyone run 6.8:1 compression?
