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Discussion Starter · #21 ·
ok. i MIGHT be able to get a 14 to 1 piston for, well, dont kno yet on the price. BUT it is a used piston, I may want to just get new if the 14:1 is questionable in its condition....lol

not sure yet....------CP is suposed to be quite a good piston, correct?
 

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Yes CP is good, I'd steer clear of Diamond pistons if that is the 14:1 you're looking at. Diamond has an excellent rep in other racing venues (so does JE) but IMHO the "cam profile" on the diamond is way too much for longevity.
 

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Discussion Starter · #24 ·
ok. thanks sto.. il deff check into the 12.5....and with a stage 3, wouldnt 93 octane fuel be about enough? or is the raptor combustion chamber not very good, therefore race fuel is needed sooner than say a yfz...?
 

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At sea level, you'll need to mix some 116 with the premium. A 2/3 to 1/3 mix of 93/116 will give you a 98.6 MON, which is about right for that combo.
 

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Discussion Starter · #26 ·
more questions. lol. i can get 87 octane gas here at the farm for free. lol. how much to mix with that to get the 96 ish MON...?

also, could i run 2 base gaskets to make it 93 safe? just thinking lol. if i have to run race gas, il prolly not even run a a base gasket, if the deck height is good..
 

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You would have to go up to about 40% 116 to 60% 87
The base gaskets are .007 thick each. If you decide not to run one be sure to check squish and piston/valve clearance.
A second base gasket still won't get you down in the range you need for 93, why not just run an 11:1 piston?
 

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Discussion Starter · #28 ·
lol...im power hungry...if ima run a stage 3, i want more comp. and i got a 12.5:1 102 mm piston with a matching cylinder with very low hours on it for 100 ish bux shipped.......can still c the hone marks in the cylinder....i actually have 35s on the way as well.....i gotta stop this...im spending way too much. lol:shame:
 

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you'll like those FCRs, just start exercising your thumb muscles now and make sure they have the YFZ throttle spring already on them. They will eliminate that surging you get in really rough terrain as the slides are tied directly the the trottle shaft, not vacuum operated like the stockers.
 

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Discussion Starter · #30 ·
lol. ok, thanks for the encouragement on the FCRs. they cost so much... but i figured id try them for myself.... and they hold their value decently........(i bought used)
and hopefully my new build will run descent. lol...........

on another note, il try to check what all VP fuels that shop down the rode has.... and go from there...
 

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Discussion Starter · #33 ·
well stopped at 2 places this morning on the way home from town...the VP 110 is real popular, and to get C16 i would have to a order in sometime....and might cost me...i MAY check a few more places out if i can find some more around....

so should i start with a 50-50 mix of 110 and 87?
 

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The MON is what you want to pay attention to. Pump gas (and even some race gas) is figured by taking the Research Octane Number and adding it to the Motor Octane Number then dividing by two...which is why the label on the pump says R+M/2. The RON is always higher than the MON but the MON is more in line with what a running motor will see. The MON of pump gas varies a bit by manufacturer. I.E. shell 93 has a different MON than Exxon/BP 93 and it takes a bit of research to find those numbers.
For your purposes it isn't critical to know the exact number since you're not going to be on the ragged edge. Just assume a MON of 84-85 for 87 pump gas and use the MON of the race fuel to shoot for a mixed MON of 96-98 for your setup.
 

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Discussion Starter · #37 ·
^ thanks, man... hopefully i like the extra comp and dont mind paying for race fuel. lol. at least im getting my 87 for free... that helps
 

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Discussion Starter · #38 ·
ok, so taking the average of 85MON and 107MON, i come up with 96 MON. perfect..... what do i figure the MON of ethanol free 93 pump gas is? i have some of that setting in a sealed jug left over from when my 660 actually ran. lol
 
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