Compression
Posted: Mon Nov 29, 2004 8:35 am
Is 98 octane ok for 11:1 compression? Or do you need to a fuel additive?
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Compression
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Posted: Mon Nov 29, 2004 8:38 am
My 2.8 with 10.8 CR pings on leaded 4 star fuel. Are you going with twin plugs as that should help.
Posted: Mon Nov 29, 2004 9:19 am
yep twin plug ignition, super unleaded, just want to make sure 11:1 will work before I get the final engine spec sorted
Posted: Mon Nov 29, 2004 2:48 pm
Luke
Whilst (stating the obvious) a much later car, 964's initially ran 11.0:1 with 95 RON fuel; only when the CR was raised to 11.3:1 did they move to 98 RON.
Of course these were twin plug from the outset.
Hope this helps.
Whilst (stating the obvious) a much later car, 964's initially ran 11.0:1 with 95 RON fuel; only when the CR was raised to 11.3:1 did they move to 98 RON.
Of course these were twin plug from the outset.
Hope this helps.
Posted: Mon Nov 29, 2004 2:55 pm
cheers Ian, it looks like 11:1 compression is GO! I finally have the full spec for my engine build now, lets hope Santa is good to me this year!
Posted: Mon Nov 29, 2004 4:43 pm
and a sophisticated engine management system, probably with knock sensors......964's initially ran 11.0:1 with 95 RON fuel
Posted: Mon Nov 29, 2004 4:46 pm
Forgot to mention that minor detail. Oops! 
Posted: Mon Nov 29, 2004 4:53 pm
but as long as everything is set up within tolerances there shouldn't be much of an issue running 11:1 as compared to 10.3:1, I just wanted to make sure I'd stillget combustion rather than detonation, all I really need to worry about is the clearances, which will be damn tight!
Posted: Mon Nov 29, 2004 5:07 pm
Luke
Nick makes a valid point. You don't want to destroy your [freshly built] pride and joy...
Suggest you stick a post on Pelican's forum if you want to ask a wider audience - some of those guys have done some pretty interesting stuff!
Nick makes a valid point. You don't want to destroy your [freshly built] pride and joy...
Suggest you stick a post on Pelican's forum if you want to ask a wider audience - some of those guys have done some pretty interesting stuff!