Planning ahead for a forged rods/pistons ls2 or ls3 short block and more boost.

It looks like with my current fuel system I will need to reduce my alcohol content to keep up with demand.

E50 should do it without giving up much. I also talked to a Sunoco rep that said their 260gt would work well if I wanted to use race gas to reduce alcohol content without giving up octane.

So of my options which do you guys recommend...

E50 using 93 to cut it down
E50 using race gas to cut it down
E50 using 93 plus water/meth.

 

You will be fine on e50 alone, keep it simple

And don't be mixing any leaded race gas with ethanol

 

I’m aware of the issue with mixing leaded with ethanol as well as some other substances used to raise octane. That is why I contacted Sunoco about their 260gt. Their 260gt plus and 260 gtx are also unleaded, but one of those has something in it that doesn’t play nice with ethanol.

 

I've posted this many times over the years,,
I have sold race gas to road racers (SCCA) for quite a few years, and have had the privilege of getting to hang out with chemists from various fuel companies while sellign fuel to IMSA/American LeMan etc.. couple things they told me.

1. Gas is IR/UV sensitive.. You can prove it for yourself, put a pint jar of race in a jar in the sun for a hour, it will often start to precipitate the additive package out of the fuel. It does not hurt as long as the fuel is used right away, and kept agitated.. Wondering if anybody with the clear tanks has noticed any issues? Because I've seen race gas go bad in a day in the white moto cans.

2. Racequipe now says to NEVER leave blended fuel in a fuel cell, they can't find a material that resists the combination of the ethanol AND the octane package sin the newer gasoline's and pump gas is the worst offender of breaking down the fuel cell bladder seams (They are made and glued together in sections...)

3. Mixing pump gas and race gas is a bad thing. The additive packages are generally NOT compatible, street gas is formulated to reduce evaporation, race gas is designed to evaporate fast. in most cases the octane contributors in race fuel and street fuel are not additive, they are subtractive. So mix 92 street with 104 race and you could get 89 or 140 there is no guarantee... The formulas in street fuel change constantly (IE weekly) because they buy the cheapest chemical available on a commodity market and is blended at the distributor by the truck driver... Race fuel starts out refined to a higher base octane and the package is blended at the refinery by chemists to get quality control, and usually only changes slightly throughout the year.


YMMV Literally ,,,,

 

I run e85 and meth. Myself and many others have been doing it for years and it works great. Leave the race gas alone. At the very least run e50 only.

 

I've had nothing except troubles with my fuel system. I built it myself with an external Magnafuel 4303, their boost referenced regulator, Deatschwerks 95 lb/hr injectors, -10 an out of tank to pump, -8 to rails, stock feed as a return. I had already hit 100% duty cycle on my cam only ls1 at 14 psi. No way I'm over 600-650 rwhp so I shouldn't be any where near 100% duty. So I checked filters and right off the bat my post pump magnafuel filter was plugged. Taking care of that dropped duty cycle a little with no other changes, but still over 90%. Magnafuel said replace the -10 an line from tank to pump with a -12 so I did that this week. No improvement. I was reading pressure off a gauge that I had on the rail. Today I decided what the heck I'll try another gauge and put it in the port in the regulator rather than use my fitting with a port off the rail. Wow base pressure was way low! I adjusted fuel pressure to give me the 58 base I thought I had and with the car idling at 14 inches of vacuum it idles at 51 psi fuel pressure all seems good except now super rich obviously. So I pull a bunch of fuel out of it and test. Just got back and with AFR in boost in the 10's all the way up to shift point I was only at 73% duty cycle.

I'm still going to add the water/meth to it when the time comes for a forged motor so I can start pushing the D1x harder. I will not drop my alcohol content like previously planned unless I have to.