mixing pump gas with 110 octane

Do you guys think I can get away with mixing 93 with 110? The motor is a bracket racing deal & the pistons are je with 1.760 comp height 4.440 bore set at zero deck & c9ve heads. JE says 11.8 to 1 with 72cc chamber heads.

Just run it with the race gas. If you get detonation, you're not going to be able to hear it, and you'll be getting cap walk. You'll then think the block is weak, when it is the detonation that is causing the problem.

Hope that helps,

Dave

mustangjeff wrote:Do you guys think I can get away with mixing 93 with 110? The motor is a bracket racing deal & the pistons are je with 1.760 comp height 4.440 bore set at zero deck & c9ve heads. JE says 11.8 to 1 with 72cc chamber heads.

NEVER MIX FUEL

BOSS 429 wrote:

mustangjeff wrote:Do you guys think I can get away with mixing 93 with 110? The motor is a bracket racing deal & the pistons are je with 1.760 comp height 4.440 bore set at zero deck & c9ve heads. JE says 11.8 to 1 with 72cc chamber heads.

NEVER MIX FUEL

What is this based on? I ran mixed fuel for years, and well as many others. Never had engine damage or other funky gunk in the engine. What do you think the fuel suppliers are doing?. Theory is one thing, and proven is other. Years back, Union 76 had a chart for mixing race gas with pump gas, and what octane you would end up with at different ratios.

Dave

DYNO TESTING, facts,and spec weight of fuel, mixing say 112 with 93,just lowers the 112,and changes the weight of the fuel,people think it helps,and it might a little for a few,


tried 87 to 93 to 99 mixed with 100 to 116, most people dont think about weight of fuel for jetting,

for exp. 11.7 engine the guy was running 93 street gas, when raced he mixed 108, ans sometimes 110 w/93 it ran good, plug was not as readable as i like them,

we switch to straight 108 made around 29 more hp then mixed fuel, now plugs looked great, no jet change ,

i dont rem all the details,but afterthat pull i changed timing,and cruve,car picked up when engine was reinstalled

-rich

[quote="DJOHAGIN"]

BOSS 429 wrote:

mustangjeff wrote:Do you guys think I can get away with mixing 93 with 110? The motor is a bracket racing deal & the pistons are je with 1.760 comp height 4.440 bore set at zero deck & c9ve heads. JE says 11.8 to 1 with 72cc chamber heads.

NEVER MIX FUEL

What is this based on? I ran mixed fuel for years, and well as many others. Never had engine damage or other funky gunk in the engine. What do you think the fuel suppliers are doing?. Theory is one thing, and proven is other. Years back, Union 76 had a chart for mixing race gas with pump gas, and what octane you would end up with at different ratios.



no theory here , dyno,and track proven



ya ,and it probaly help them sell fuel to street guys, just like going to the track,watching kids drive there 9.1 cars there,and then putting in 112 /114, and then telling everyone wow race gas helps


-rich

Rich,

I agree with you on all your statements, except with the blanket statement on not to mix fuel. Yes, you have re-adjust when mixing, but it does work. And yes, using straight race gas when necessary produces the best results.

Dave