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Dome Size


Jhughes7

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I'll be calling you in the next few days to order my new cool head :) Think I am gonna go with 20cc domes, I wont be advancing the timing for awhile so hopefully 20cc will be fine for 50/50

 

20cc domes will be fine with one gallon of race fuel to 4 of 93. Depending on your compression after you install the 20s you might be able to get away with straight 93. Thats what I have and Im kicking 150 in each and 93 is definatly enough. When I advance my timing that will probably be a diffrent story though.

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357hp, isnt 150 kind of low for 20cc domes? im getting 147psi and 148psi with 22cc domes.

 

the noss machine website says with 20cc you should be at around 169psi

 

 

yeah I read that earlier Ithought I was to low & you were high? Wasn't to happy been running 110 (just incase ) for nothing $$ :banghead: $$

I didnt warm it up or clean the filter but, that won't change much so :shrug:

also I was just going by what the guy said when I bought it. I told him I wanted all the old parts If he still had them (so I would know what he really did change) but that didn't help going stock to cool head it's any body's guess what he put in there

Edited by 375hp banshees
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There are lots of variables, among them elevation, porting, compression guages, piston type, etc. One of the things that gets overlooked is the depth that the compression tester threads in to the head/dome. A bunch of the testers have short parts that thread in. If it's shorter than the spark plug threads a false low reading will result.

 

Sometimes just a little more octane is all you need to be on the safe side, like in Washburn's case.

I bought 100 octane avgas at a local airport a couple weeks ago for $2.85 per gallon. It has a lot of lead in it and has a very long shelf life compared to pump gas.

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There are lots of variables, among them elevation, porting, compression guages, piston type, etc. One of the things that gets overlooked is the depth that the compression tester threads in to the head/dome. A bunch of the testers have short parts that thread in. If it's shorter than the spark plug threads a false low reading will result.

 

Sometimes just a little more octane is all you need to be on the safe side, like in Washburn's case.

I bought 100 octane avgas at a local airport a couple weeks ago for $2.85 per gallon. It has a lot of lead in it and has a very long shelf life compared to pump gas.

 

Like I said. I plan on being in the high 150s when I install my timing plate and Im going to run 1 gallon of VP110 to 3 gallons of 93. That should be plenty. I dont think its to good of an idea to have above 160-165 in a stock port engine. Thats major wear on your crank first and foremost and your running that race fuel without running as strong as you can run without porting cause porting actualy bumps your compression down due to bigger ports. Im breaking my own rules running a 25% blend in mine. Gotta save up for shocks though while running as strong as I can for the time being untill I do port my engine out.

 

Im definatly looking into that 100LL AV Fuel though. I figured it was like 4 a gallon. As always Good looking out David :thumbsup:

 

Oh and I bought the compression tester with a 14 and 18 mill adapter. The 14 mill is a few screws shorter than the plug and it is very accurate. But the 18mill is longer than the plug and it will hit the top of your piston when you do the compression test. I got mine at Autozone.

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