How much compression will i get with 283 heads on a mid 80s 350 with the dish pistons? Now that you think i'm nuts(LOL):My Car runs on E85 ethanol 106octane,and next week i'm gonna install an LPG Gas system that has about the same rating. I dont care if the engine will hit home at 4500 since its in my 58wagon,thats never gonna win a race.Low end and economy is all that counts! Thanks a lot, OldschoolOlli
It shouldn't be that hard to figure out but you will probably have to put in new valve seats to handle the lpg without pounding out the stock seats.
Using a 12cc dish which is common on 350's, .025" deck height, 58cc chambers which is about what the 283 Power Pak heads average and an .041" thick head gasket you'll be right about 9.5 to 1. I use this calculator: http://kb-silvolite.com/calc.php?action=comp
Oh yeah,the hot ***bostion of LPG! Ok,but when it comes to these calculations....guess i'm more the practical backyard garage guy. Who can help? cheers, OldschoolOlli
Hey rudebaker,big thanks! Say would that 0.41 gasket be something like the thick blue fel pros? Cause thats all you can get,on this side of the world... thanks, OldschoolOlli
Not trying to start a ******* match, but...I have to question the accuracy of the claim that 'most' Power Pack heads average 58cc. My '57 Fuelie (Power Pack, '539' casting) heads CC'ed at 64cc before milling and larger intake valves, and measured 62cc after. In fact, the chambers on the '57 '539' casting heads are smaller than most later Power Pack heads' combustion chambers. The only Powerpack heads with smaller combustion chambers are some '56 castings ('306', '762') and the '57 '997' castings. My advice would be to CC the chambers on whatever head you end up with....too many people just make "educated guesses" when it comes to combustion chamber volume. That way you can be a little more sure where your static compression ratio will end up.
Thanks B***! I just needed a ballpark.Now i see that the result will be not all that dramatically high.Not bad,might run on pump gas too.Cause that is 95 here.But they have 98 and 100 too.. Here i am getting the heads(dirt cheap).Thanks hambers! OldschoolOlli
Here's a picture,if that helps.The chambers don't look that small,if you ask me. But the i'm a ford guy,so who knows? thanks, OldschoolOlli
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