Reply With Quotei would keep the 10 - 11 :1 ratio they have. you could go abit higher and maybe back timing off a little if it detonates . that way if you run good fuel/ octane booster on a track day you wind the timing back in to get alittle more out of it.
Selecting a compression ratio for a 20V
what is a good compression ratio to run for a ported 20V blacktop 4age engine? Assuming that it is to be run on 98 octane pump fuel. Is it better to have a medium compression ratio and advance the timing more or have a high compression ratio with less timing. I am after the maximum area under a power curve from 3000 to 8000 revs not absolute max power.
Re: Selecting a compression ratio for a 20V
i would keep the 10 - 11 :1 ratio they have. you could go abit higher and maybe back timing off a little if it detonates . that way if you run good fuel/ octane booster on a track day you wind the timing back in to get alittle more out of it.
300+rwkw 4agte http://www.toymods.org.au/forums/for...wkw-4agte.html
Re: Selecting a compression ratio for a 20V
totally depends on the dynamic compression ratio..
are you going to run stock cams? or 320deg monsters?
bigger cam = lower dynamic compression = higher static compression needed...
higher compression will giove you more torque, but get you closer to problems...
especially if you get a bad batch of fuel (or are forced to run optimax)
10-11 is pretty high for street fuel already.... for stock cams (260?270?)
maybe 11:1 and hope it doesn't ping
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Re: Selecting a compression ratio for a 20V
sorry forgot to mention that, original cams. It runs fine on 95 octane fuel.
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