Hey guys, I've got a 94 c4 6 speed manual swap with the lt1 rocking the cc306 with 1.65 rockers, 44lb injectors, full length headers, 58mm bbk throttle body, the torquehead 24x kit and a few other minor supporting mods.

I've been wondering about running e85 recently, I live in Iowa and e85 in my area is currently $1.50/gal while 91/93 is $4+ and I've been running vp racing octane which claims up to 8 octane numbers. without the octane booster I have some drivability issues but it's still completely drivable. However it would much cheaper to just run the e85. I know to add ~30% to my fuel map, possibly add more timing and should change my hoses all to some kind of stainless or e85 safe line, but I was wondering what else I would need. Do you think I'll need a bigger fuel pump, or anything? or will it run on my current setup? please let me know and thanks guys

 

On a mass basis, its more like 43%-50% more fuel depending upon which fuel you use for a base (E10 or ethanol-free gas).

What is the current power level, injector duty cycle and fuel pump capacity? If over 60-70% injector duty cycle now the injectors are borderline, but the fuel pump is likely the primary limitation.

You can always blend fuel up to the limits of your fuel system and gain some if not most of the benefits, if desired. On another car I run about an E30 blend, since that's about the limit of the car's fuel system.

As you can see here, its about out of fuel (injector-limited) up top: https://datazap.me/u/tequilaboy/evo-...mark=2847-2862

Brake-boosting here for boost control tuning/evaluation purposes (not fuel limited): https://datazap.me/u/tequilaboy/evo-...2285-2323-2305

 

what kind of engine management are you using? i wouldn't be using ethanol on anything less than a holley, haltech etc.

be sure to have a LOT of fuel filters handy.

 

Try it and see how it works. I ran e85 in my 1986 and the only rhings i changed were fuel pump, injectors and tune. Car ran great.

 

I've got the torquehead 24x kit so I'm running on an LS pcm

 

Thanks for the info, however I'm wandering about running 100% e85 and not mixing different fuels.

 

im not familiar with that setup. i presume it is ignition only? does it utilize hptuners for modification?

fuel will be your biggest change. maybe a few degrees of timing to capitalize on ethanols resistance to knock.

 

Ask yourself how often you drive your car, and how long it may sit between uses. Ethanol is well known to attract water, and when that happens, it becomes a gel that gums up filters, pumps, and injectors. If your car is a daily driver, no big deal. But if it sits for weeks or months at a time, as can happen in the north, then you WILL have problems. Keep using it if you want, but made sure you can take the top hatch off your tank easily so that you can clean it out, if it starts precipitating out during storage. OR store the car with better gas than that if you can. I've had it happen with boats, and you don't want that headache.

 

i've used ethanol in a 2018 camaro for several years. the longest it sat in the car was about 9 weeks, up until 2 weeks ago. it was well below freezing for several days in my detached, unheated garage. no adverse affects, but i certainly wouldn't recommend it. historically i always put it up for winter after running a couple tanks of 93 through it first.

 

Not sure I have any more to contribute, but let me say a few things. Best way to do it is to install an ethanol content sensor, and add fuel volume % to VE tables for tuning. And a wideband controlled/monitored system. Since AFR is lambda based from the wideband, you don't need to change the targets, as indicating 14.7 is still 1.0 Lambda. Timing is a little bit more complicated to manage, but you can add timing for knock limited timing areas of the ignition timing map for improvement. This area is limited for 10:1 compression but larger of course for 14:1 or forced indction. E85 pumps can provide anywhere between E55 to E95 (supposed to be E55-85 but sometimes it well exceeds the 85), so you would be dedicated to a single batch/pump for fixed tuning, without accommodations for having to add gasoline to manage E20 E30 E40 E50 and so on trying to manualy test it and change. Pump gas here is E5 to E10, so there's a lot of math and testing to do otherwise if you have partial E85 and E10. All this is easily done with a modern Holley EFI, I don't have any tuning experience with TQH.

Add Lucas E85 treatment to every tank full, or you'll be growing a corrosive swamp after some time. Steel and aluminum parts especially effected, for full E85 long term you should most definitely have stainless. Gasket, O-ring, hose, injectors, FP diaphram materials also need to be compatible.