In light of what I found out on race gas pricing, and the fact I drive my car quite a bit I'm not looking to spend hundreds every week in car fuel for my daily driving fun, so I went back and started rethinking E85 since we have it here in the midwest and a station just down the road per say.

What is all involved with converting a carb to run this E85 stuff?? What other things do I need to be aware of/need to change so I can have a long fuel system life with minimal problems. I have to get a new pump/filter set-up anways, do I stick with the braided fuel line I currently have? do I switch it out to aluminum??

Who does E85 conversions for carbs, and I guess what does it consist of? I currently have a 950HP.

ANY and ALL comments and help greatly appreciated!! I would love to go in a different direction, or something not as main stream, but dont want to have regrets either with failing parts

 

So you cruise around on race gas all the time? I'm assuming your talking about a fast street driver, right?

Ken R.

 

I'm a wasteful person as my wife tells me. My car ran the best numbers on 91 octane, but I love the smell of race gas, so that's all I ran...back then it was only $3.65/gallon so it wasnt a big deal and I only averaged 1-2 tanks a week between street driving and racing so i justified it....but now with this new motor, I need to have race gas/higher octane, it's gone upto $5-6/gallon depending where I get it, and I did the math and it averages to around $175/wk for fuel if I drive it like I used to along with my race schedule every weekend all summer....I need an alternative.

Pretty much found the answers I was looking for, I plan to call a few carb companies and get pricing for comparison and order soemthing by weeks end so it's here in time for dynoing the new mill so I can set it all up at once.

 

It probably doesn't take any more effort than converting a carb to run on 100% methanol. The passages just don't need to be as big.

I'd suggest contacting the major carb rebuilders who normally do alcohol conversions to ask them if they do an E85 conversion on the Holley carbs. It would be a good market for them to get into with everyone wanting to run ethanol.

George Rupert
Davinci
APD
Karson-Bloom

What about using a Ron's Fuel system on E85?

 

I dont know how streetable Ron's unit maybe, or even James....would be diffferent on a street car though LOL!!

Today-depending on how hard we get with SNOW again...WTF???? I'm going to contact a few places-Quick Fuel, ADP, AED, and some of the local guys racers have given me info on and see where I stand and what would be the best route to go-be it just outright buying a new carb, or sending mine in for upfitting...I would like to keep mine and build another motor and have it sitting on stand by, but I also dont need a near $700 carb just laying around rotting and drying up either...will know more by the end of the day, is'nt nearly as bad as I thought it might be, and will be nice having it prepped pre-dyno so we can really tune the mix and I can see first hand how touchey the stuff is.

 

Just get an alcohol carb in the appropriate size and be sure your fuel pump will handle the extra volume (~double gasoline). A carb will be jetted for M100 will be rich an E85, so you will need to go down a couple of main jet sizes, etc. Or, contact any specialty carb shop depending on your budget and carb tuning skills. Also, run a plug one or two heat ranges hotter. You will also probalby need to advance your ignition a few degrees.

If you do it, I'd be curious about any performance change. In theory, you should be a few ponies down.

Rich

 

In theory I should be just fine if not a little better off as I'm pushing the envelope compression wise already, but I should have enough bleed off with cam specs so I'm not swweating it. Motor is built using 13.5:1 slugs, but I ordered my heads with 68cc chambers, am using the steel shimmed headgaskets that are a little thicker and shooting for overall static compression of 12.6-7:1, dynamic comp, I have no idea and will have to wait until the rest of the parts get here and cc'd so we know exactly what is going on. Either way, the motor needs race gas or alcohol, and given the specs it's not too often methanol doe'snt outperform gas.

 

I believe that ethanol has less energy content than methanol at an equivalent mixture. So, I am curious how it works out.

Rich

 

I was too lazy to pull up numerious serch articles relateing to this subject, but BTU wise your right, it's less than methanol. The funny thing, I spoke with 3 major carb companies deciding which route to go-sending mine in to have redone, or buying a brand new-already set-up carb for the E85, getting mine rebuilt is the way to go $$$ wise.

Anyways, ADP, AED, and Quick Fuel have all been working with builders setting up E85 race engines and everyone of them seen an increase in power when switching from race gas to E85, the 20hp increase was a number all three used when talking about increase increments over race gas.

I'll know by friday-actually by end of today-which company will get my carb, turn time is longer than I want, but I'll pay to have it overnighted both way to cut out time that way since this motor should be done in a week-week and a half Fedex dropped off a bunch of stuff htis AM, my other local parts vendor called and has all my valvetrain stuff in, shop i ordered my heads from said they'll be in Fri morning...it's all coming together

 

I love the smell of race fuel to lol, id run it but im not sure what that would do to injectors etc being leaded. Plus O2's.

 

My exhaust fumes smell mostly of formaldehyde but has a slight cherry scent from the additive I put in my methanol. Still burns the eyes if you're downwind of the exhaust.

Found some fuel specs

Gasoline
115,000 Btu/gal
86 motor octane
14.7:1 A/F ratio

Methanol
57,000 Btu/gal
91 motor octane
6.4:1 A/F ratio

Ethanol (100%)
76,000 Btu.gal
92 motor octane
9:1 A/F ratio

Isopropyl alcohol (rubbing alcohol) <- not a great fuel but used to compare
86,000 Btu/gal
99 motor octane
10.3:1 A/F ratio

So 100% Ethanol will have a bit more BTU energy than Methanol and not need to burn as much but still more than gasoline. Typically for methanol, you'll burn about twice as much as you would gasoline. When methanol is 1/4 the price or less than race gas, burning twice as much is still cheaper. Burning twice as much methanol would produce 114,000 BTU of energy in the same time frame as burning 115,000 BTU of gasoline. Methanol however burns slowly and has a cooling affect on the engine which allows the energy to be used as power instead of being converted into heat. I'm sure Ethanol would have the same effect. Even with the lower octane rating of methanol, because of the amount of fuel that's being dumped into the engine, the chance of detonation is next to nil in a high compression engine. My engine is around 13:1. Methanol will run with 8:1 compression but prefers a compression ratio in the low 14:1 range.

Even at 85% ethanol, there could be some good performance advantages. I doubt you'll see many racers like me who run 100% methanol switching over but switching from gasoline to ethanol could be worth it for a race car.

 

Gasoline
115,000 Btu/gal
86 motor octane
14.7:1 A/F ratio

Methanol
57,000 Btu/gal
91 motor octane
6.4:1 A/F ratio

Ethanol (100%)
76,000 Btu.gal
92 motor octane
9:1 A/F ratio

Using your numbers, you use 2.3 times as much M100 and 1.6 times as much E100 as gas at stoich. The relative energy content at stoich of M100 is therefore 14% more than gas while E100 is 5% more than gas. It's more complicated than that, and M100 does not make 14% more hp than gas in a typical application. But my impression is that ethanol or ethanol mixes are pretty much on par with gas while methanol will moke more hp, typically 5% or so. The octane rating of methanol (and ethanol as well, AFAIK) does not adequately account for the improved detonation resistance relative to gas.

Rich

 

i completely agree, you guys are already set-up for alky, have the tune figured out for where you need to be, and the price is'nt as cheap as it once was...buying alky by the drum here nets around $2.75-$3.00 per gallon plus drum deposit so it's roughly the same price as normal gasoline...but you need twice as much...but you an run a very wild combination so it's not even apples to apples comparisons since it's race only...and yes, I hate getting stuck next to alky cars in staging...I was surrounded once at the World Series and was crying like a baby in my car until I was forced to exit and get some fresh air LOL!!!

I called the buddy who will be supplying my E85, $2.25 right now at 2 of the stations right down the road from him-I have 2 55 gallon drums lined up I will fill prior to hitting the dyno up there. I also found out the shop I'm taking it to (my buddies shop) has been specailizing in E85 stuff and is really ahead of the curve so I got very lucky there...I'm yet to talk to the shop owner personally, but I'm in good company with my friend and we plan to do a race gas to E85 test and see how it plays out in my case...but since I'm building a compression motor I think I will be on the good end of the switch and not losing power like my buddy did in his ford 347 since that is only 10.5:1-they lost 23hp from pump gas to E85-just was'nt enough compression.

I'm looking forward to this, should be fun to see how it all works out, and it should make a nice conversation started amoungst peers.

 

Sounds like fun! Please post the results - I am pretty curious and I'm sure others are as well. Alcohol sure does like compression, as you said. I don't completely understand why, given the lower octane rating compared to race gas. I am told it has to do with heat in the chamber - without enough compression the alcohol is hard to light off and burn completely. That's also why it may take more ignition advance than gas. Cars running a carb and alcohol need manifold heat to adequately vaporize the alcohol and prevent problems with fuel distribution. They don't run well when cold, relative to gas. E85, with the slightly lower heat of vaporization of ethanol and the 15% gas may not be a problem. I run a port injection EFI system (with M100), so it's not an issue. But when I was running a carb, the car was always much quicker (up to 0.2sec) on the second and subsequent passes. I attribute that to the lack of heat in the top end. EFI does not show the same variability.

Rich

 

Rich, I'm looking forward to seeing how this works out and getting REAL LIFE first hand numbers I can digest as opposed to internet hear say as Im sure many others are too LOL!!

FWIW, I dont know how much time you have, but I found this on the other camaro/firebird board I goto and it has a really good article about E85 written for dragnews magazine and the actual author is spending time in there posting test results and answering questions dispelling alot of myth's. CLICK HERE and read it when you get a chance, pretty interesting...but I'm still going to wait and see my own results LOL!!!

Josh