327 with camel hump heads

[dillon_94]

will this motor run on pump gas? or should i run race fuel it has 10.5-1 so im not sure, havent tried firing it yet with either, as im waiting for the car to get done,
thanks for the help

[sj valley dave]

10.5:1 with iron heads is right at the edge...If you can get 93 octane pump gas keep the timing under control and look at your plugs for any signs of pre ignition...

[dillon_94]

would a race fuel mixed with the 93 octane work?
or maybe 93 with octane booster?

[Egoracing]

93 should be plenty if everything is right, a bur that can cause a hot spot or the engine running hot will easily put you over the edge though. Remember that an octane rating to high will cost the engine power so you can mix racing and pump but do not need much. Get a good 93 octane and mix 1 gallon of 110 race fuel with 4 gallons of pump and you should be very safe. There is a topic in the crate section on pump fuel that would be good for you to read.

[sj valley dave]

Renegade also make a 98 octane race gas that would work well for you..

[dillon_94]

im sorry i talked to the builder and he said he gave me false info and it has 11.5to1 not 10.5. how big of a difference will this make?

[dirty white boy]

you was on the edge at 10 to 1,..if it 11.5 to 1 better feed it the good stuff,..less you wantin newer pistons!!

[sj valley dave]

At 11.5:1 I would suggest the 98 octane race gas...110 is still too much octane IMO and you are giving away HP..

[DANNY]

Kind of like us... We running Rocket Red 111 and i always wondered if it was too much... We run 12.5-13 and some of us even more lol

[powerslide]

im sorry i talked to the builder and he said he gave me false info and it has 11.5to1 not 10.5. how big of a difference will this make?

Did he calculate it or go off the pistons advertised CR?

[dillon_94]

calculated

[stock car driver]

I run 110 on my 13-1 and up motors and cant say Ive tried to run less ever.

I also have a limited motor which is 10.5-1 and I dynoed it with 110 and then 110/pump 50-50 for about 100 octane back to back on the dyno.

I gained hp and tq with the lower octane fuel but more importantly it smoothed out the air fuel and hp graphs showing me that it was running much better. I didnt try more of a mix or less octane as I wouldnt have been very accurate just adding more pump gas to my cell.

I need to pre plan the mixing better and leave it in jugs and draw directly from them to compare.

[dillon_94]

thanks for the info Jeff. glad your still helping out racers on here even though everyone seems to complain about your help. i appreciated it a lot though
Thanks

[wil8115]

which cam are you running?
your dynamic compression will determine which gas is necessary.