[BigHemi]

Has anyone else noticed their pump gas engines not running as good as they used to on the premium gas available today?
I'm talking in the last 4 years or so, it seems like it's gotten considerably shittier. More detonation prone is what I'm seeing for the most part.

Is the ethanol to blame? 10% now and supposedly going up to 15% soon?

Seriously considering switching to E-85 soon. Haven't done it yet b/c it's not as readily available around here.

 

[juiced coupe 78]

The ethanol is part of it. The other part is ever tighter tolerances on fuel specs. Whats good for your engine isn't always good for the environment. This is also one of the things that drives up fuel prices. The "good stuff" was cheaper to make.

 

[Monte442]

What about an additive ? Has anyone tried and had luck with any additives or octane boosters to help the pump gas ?

 

[Relentless]

Yes my street car is 11:1 and it use to run fine on pump 93 with 30deg of timing. Now it will do nothing but idle and crusie off of this crap, cuz when i load the engine hard is pings like hell. I am now gathering parts to just convert to Alky and be done with it. I don't drive the car offten or for great distances so it seems to be the way for me. Alky is also cheaper than gas now soooooo.

My hats off the the guys that do the pump gas drags because they have got there act together.

 

[drillteamleader]

I used torco mach accelerator with real good luck on a turbo evolution at 25 lbs of boost. I just found some the other day with a new name, but still called mach excelerator.

 

[mcintosh]

I've used Power Pour with great results. Used it on a nitrous and F3R blown combo.
www.powerpour.com
Pm me if you need any info.

 

[BigHemi]

I'm pretty aggravated w/ this whole deal. I ran the pump gas drags in '08 and a lot of those guys are rattling their motors pretty hard. Mine has run fine on pump 93 for the past few years, but now it's showing signs of detonation. I'm probably going to go to E-85 and be done w/ it.

My dad's car has a combination in it that ran perfect on pump 93 ten years ago. Now I've had to take 4 degrees of timing out of it to make it somewhat happy w/o an octane booster. The motor's condition isn't an issue, it's not 10 years old.

 

[Zfan]

Just think, we are lucky we even have 93 here in Texas. Some states run 90-91 octane as Supreme these days. One engine builder in California said he recommends not building a motor over 9.5 to 1 these days if it is a pump gas street car because of fuel issues that you "WILL" run into. My little Datsun Zcar has a 385 sbc in it and I drive it everywhere but at 10.83 to 1 it's getting iffy to run more than 32 degree's of timing.

My next rebuild will be a 10 to 1 motor at best unless I add some 110 to the tank and that ain't cheap, even at 4 t0 1 or 5 to 1 mix.

 

[FuelieNova]

This is exactly why I built my new engine at 9.75:1.
Tom

 

[David 519]

Just think, we are lucky we even have 93 here in Texas. Some states run 90-91 octane as Supreme these days. One engine builder in California said he recommends not building a motor over 9.5 to 1 these days if it is a pump gas street car because of fuel issues that you "WILL" run into. My little Datsun Zcar has a 385 sbc in it and I drive it everywhere but at 10.83 to 1 it's getting iffy to run more than 32 degree's of timing.

My next rebuild will be a 10 to 1 motor at best unless I add some 110 to the tank and that ain't cheap, even at 4 t0 1 or 5 to 1 mix.

Spot on. Here in CA, our 91 has enough BS seasonal additives that you can't trust it. Most are spiking their pump gas with a bit of race gas to be safe if they're gonna be racing it. We're just finishing up a 580 and went 10:1 but thinking it might still need spiked with race gas....

 

[cnews85]

Any idea on what fuel ratios everyone is running per comp ratio? ex: 5 gall 110 fuel to how many gall of 87oct per comp ratio? I have been running in my street car 5 gall 110oct to 8 gall of 87oct in my engine at 11.2:1 comp it seems to be happy with this combo of fuel. I mix with 87 it seems to have less additives and blend better.

 

[Smoken71RSSS]

Spot on. Here in CA, our 91 has enough BS seasonal additives that you can't trust it. Most are spiking their pump gas with a bit of race gas to be safe if they're gonna be racing it. We're just finishing up a 580 and went 10:1 but thinking it might still need spiked with race gas....

True! I'm dropping the 91 octane all together this year. I don't get to the track much because of lack of funds and I don't have time to deal with the inconsistencies of pump gas even with a spike. It's risky also and lack of funds will put me on the sideline for awhile if I hurt the motor.