SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: Marcsrollin on May 09, 2007, 01:40:50 PM
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I have been told many diffrent opinions on this subject and was wondering what compression ratios you guys are running and what octane fuel you use. I am running 10.25 and have been told three diffrent things from three diffrent places. One says 94 octane and another says 100 octane and the other says 96.
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marc how is it you have that much compression with d3 heads? my 502 with d3's had 10.5 to 1 and i ran it on 92 and 38* of timing. let me know. somewhere on the forum i posted a comp ratio calculator. i'll look around and see if i can find it.
ralph
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comp ratio calculator (link) (http://www.socaljetboats.com/index.php?topic=511.0)
well the link didnt work but my post is about 10 or so below this one
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The tag on the orginal motor mount says 94 octane and 10 degrees of timing.
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just run 92 and youl befine if it pings pull a little leed out of the motor ;)
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just run 92 and youl befine if it pings pull a little leed out of the motor ;)
thats what i'm saying.
how much timing do you have? do you have flat tops, dished or domed pistons? now i'm not really shure about this but how much is your timing at the gear? straight up or does it have advance allready in it? should be like 8* or something.
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also it sounds like alot of timeing it should be around 36 34 give or take also is the dist locked out so its advanced all the time that makes a diff on timeing to
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just run the 92 ;) or start tearing the engine apart >:D
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i say run it tell it gos bang then build the sheit out of it ;D
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Sh*t, I'm just trying to figure out some fuel for mine. Anybody know anything about additives/ octane boosters? Whats the best gas you can get ON the river/lakes?
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none on the river and lakes to much agua octane boosters are okey but by the time you pay for 92 and the octane boooster better of paying a few cense more for some 106 race gas just my thought ;)
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yea, i hear ya.....just don wanna run to the airport or carry cans everytime i need gas
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every time i go out its 2 drums of vp 112 700 bucks every time the boat goes out :o a buddy of mine thats on here has one of my old drums and he fills it up a flying j 92 for about 3.00 a gall cheaper than race gas and eiseir then pulling the boats to the gas station all the time at the river
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I've talked to Marc about this so I guess it's OK to fock up his thread >:D
What is total timing? How is it figured out? What does it mean? How can it be changed?
I can set a SBC at 10 before TDC but what in the hell is 38, 43, hut hut hike? ;D
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38 and such will be your TOTAL advance, after your advance is all in. 10 btdc is your initial advance, like at idle. You gotta run your RPMs up to about 2500 to set total advance, then check where your initial lead is, subtract that from your total and thats how much you have in your distributer.