I'm contemplating my upcoming build of my 400 HO which is stock at 10.75:1 compression ratio. I know this is too high for todays fuel, and there are recommendations (good ones) to reduce the compression ratio and quench area with dished pistons and other good stuff, and either modify the 670 closed chamber heads I have or get some open chamber heads. I have also read other places that running E85 can save a whole lot of modifications if the carb gets set up richer, and care is taken to ensure the fuel pump has enough capacity for the extra volume of fuel that is required, and ensure the gaskets and seals are compatible. The 105 octane rating of the E85 will be helpful in eliminating knock. Does anyone have any experience with this?

Have a look at my 400HO on the test stand I built. This is the 1st time we started the engine after engine was reconditioned.



This engine is completely stock. 1st rebuild done some time ago but engine is still very stront. All I needed was a valve reseated.

Pistons were not dished but cam was a special grind,. Not sure how it was modified to allow for pumped gas but you can here it...
sounds great on pumped gas!

I rebuilt a 1967 400 that had 670 heads. I used dished icon pistons that brought compression down to 9:1 and used the summit 2801 camshaft. Runs great on pump Piss gas we have today.

There is a lot of online info about E-85. You can buy Holley/Quick fuel type E-85 carbs. Some even say they can build E-85 Q-jets.

One problem seems to be the quality of the E-85. Many times it's not exactly 85% ethanol. And the percentage changes from the warm weather months to the cold weather months.

Obviously the ethanol content will have a great effect on carb tuning. There are test kits to determine the amount of ethanol in the fuel you buy.

https://www.amazon.com/Quick-Fuel-Technology-36-E85-Sample/dp/B007ZJ749O

http://www.jegs.com/p/Holley/Holley-E85-Fuel-Tester/2883596/10002/-1

But, assuming the carb is tuned for the fuel you have, E-85 has some real advantages. Besides being high octane, it also makes the engine run cooler.

Some say it attracts moisture. And it won't get as good mileage as normal pump gas.

I'd prefer to build with less compression or use Torco Accelerator octane booster.

I wouldn't even use E99 in any of my old 'birds. That stuff is a gooey mess waiting to happen.

It should be outlawed ASAP!

Obviously there are LOTS of guys who don't feel that way about ethanol, at all. And, I assume that more than 99% of all gas powered engines, in this country, use gas with some ethanol in it.

https://www.google.com/search?q=e-8...610j0j7&sourceid=chrome&ie=UTF-8

I was expecting more negative comments. My machinist says he's running 13.5:1 (not a Pontiac engine) using E85 and loves it! He says it really helps keep his engine cool. All options are being considered at this point. Thanks for the feedback - both ways. Are there any good reasons NOT to use it? I don't mind changing out the fuel lines and fuel pump. I know the carb will cost me some to get it built correctly to run on the E85, but in the long run it might be a good option. Yes, I know the mix varies throughout the seasons, anywhere from about 70 to 85% ethanol. I will need to deal with that, and test the fuel content as the seasons change.

Gus68, nice video, and it does sound good, but that's only at no load. Detonation is much more prevalent under load with a hot engine. Do you have the engine in the car now? Any issues with detonation or pre-ignition?

How so?
Typical exhaust gas temperatures on a properly tuned engine run between 1100-1400 degrees and can go as high as 1600 degrees depending on how much of a load is on the engine. Temperatures don't vary more than a few degrees from gasoline to alcohol to be running at a proper air fuel ratio.

Maybe because of rumors started at places like this:

http://www.superchevy.com/how-to/additional-tech/1110chp-e85-fuel-switch/

"Additionally, for advice on how to convert a gasoline fuel system and carb over for E85 use, we chatted with Marvin Benoit of Quick Fuel Technology."

"Cooling Effect

Marvin Benoit: In addition to the octane advantage of E85 over gasoline, since it’s an alcohol-type fuel, most motors will generally produce more torque on E85. In fact, we have local NHRA Super Street racers who have had great success running E85. For bracket racers, the lower cost of E85 makes it a great deal. Furthermore, motors will typically run 15-20 degrees cooler on E85 than gasoline. In some cases, that can be enough to solve overheating problems. Ultimately, you can put a bigger motor in a street car with E85 without having to worry about overheating, and have more horsepower thanks to the cooling effect of the alcohol content."

Sounds like your machinist has the info you need. I'd stick with his advice, and build...as long as he'll gaurantee the results. No reason he can't transfer his knowledge to a Pontiac engine.

Re E85: higher octane, cheaper price, and cooler running?! What aren't we all using it?

I haven't run across any down this way...

Don't know how current the info is. But one site shows E-85 in 3 places along I-12, between BR & Slidel, and several stations in BR. Just curious to know if any of these locations still sell E-85 ???

I'm right in the middle. Any close to Mandeville? ...105 octane?

Widely varying quality of the product is part of it.

Isn't there a standard to which this type of product is produced?

Think about it. If the attributes mentioned above were factually true, E85 would solve a lot of problems many of us have experienced...

Don't worry about installing a 4 row Aluminum radiator, or checking the clearance on the divider plates in your water pump. E85 will drop your running temp by 20 degrees! Hell, add water wetter and you won't be able to get up to your thermostat's temperature rating!

No worries about static or dynamic compression ratio. The 105 octane of the E85 will resolve that. Run those old heads without worry!

C'mon guys! You know better.

I'm no E-85 expert. But, I've read that the % of ethanol changes, when the weather changes from hot to cold. I'm assuming that means that the % of the mix will be different, in different parts of the country, at different times of the year.

E-85 was not made to give hot rodders a higher octane fuel for their high compression engines. It was supposedly made for modern, flex-fuel vehicles. I assume that the original purpose of ethanol, as a fuel, was so that we'd use less crude oil. It got real popular when gas went to $4 per gal, because it was cheaper. A different gas/ethanol mixture is no problem for a flex-fuel vehicle, since everything is computer controlled.

But, some hot rodders discovered that E-85 has high octane & runs cooler. And since most racing gas is around $10 or more per gal, E-85 is much cheaper. So, it made a lot of sense to try it in high CR engines. A lot of racers have used it & like it. My engine guy built a 4.5" Pontiac stroker, for a modified dirt track car I owned. On E-85 it made 755hp @ 5900rpm. It ran strong on the track & never came close to overheating, even after many consecutive laps.

E-85 carbs are readily available. The main concern with using E-85 is the ethanol content variation. The E-85 guys use ethanol testers, so they'll know the ethanol content of the E-85 they buy.

http://www.hotrod.com/articles/ccrp-1211-do-it-yourself-e85-testing/

http://www.jegs.com/p/Holley/Holley-E85-Fuel-Tester/2883596/10002/-1

https://www.amazon.com/Stens-750-76...mp;psc=1&refRID=K8AMAN3V7KT88NARZN8F

For seasonal variations, I assume that jet changes may be about all that's needed. All the race fuel companies offer racing grade E85 that's always a true 85%, and has more octane. But, it's only a little cheaper than race gas, therefore wouldn't be of great benefit to street guys. Some street, street/strip, & race only guys are using E-85 & love it. So, it's an option for those who wanna use it. For others, they can just stick their head in the sand and say it's no good. The choice is yours.

https://www.holley.com/blog/post/drag_racing_with_e85/

The OP isn't talking about a race only application. Unless I'm misunderstanding his query, he's asking about a relatively stock rebuild, and how E85 will save the cost of more expensive modifications.

My point is that you're not gonna resolve the detonation and over heating that some of us have/had on our stock engines by switching to E85 you can get at a " regular" gas station. You'd have better luck going to the Abita Airport and filling up with low lead 100 (which I have...it's awesome! ...and smells a lot better.)

I think the OP building an engine without the normal modifications for modern fuels, thinking E85 will eliminate the need, would be foolish. That's not sticking your head in the sand. That's doing your homework and using common sense. No disrespect my Louisiana brother. I just don't agree with you.

"...No disrespect my Louisiana brother. I just don't agree with you."


Yeah, I don't agree with you either.

I have never used E-85, and never plan to. I'd mix in some Torco Accelerator octane booster, instead. But, for those who live in an area where it's readily available, at regular type gas stations(yes it is available at some stations, where they also sell other grades of gas, plus diesel. I doubt that there are any E-85 Only stations) it is a viable option. According to online info, there are quite a few STREET DRIVEN cars that run E-85. And there are plenty of E-85 carbs, & E-85 carb conversion kits, and carb rebuilders who will convert your Holley type carb over to E-85, and E-85 ethanol test kits.

https://www.e85carbs.com/

https://cliffshighperformance.com/simplemachinesforum/index.php?topic=1963.0

So, to say that E-85 is not a decent option, for high compression street engines, is pretty ridiculous to me, when guys are doing it every day, and love it. Again, it must be available in your area.

http://www.hotrod.com/articles/hrdp-0801-e85-ethanol-alternative-fuel/

http://www.hotrod.com/articles/converting-from-gasoline-to-e85-for-the-street/

http://www.yellowbullet.com/forum/showthread.php?t=575138

I may have to explore this route, E85. Long story short, after some modifications were made to my iron cylinder heads, the resulting compression ratio is in the mid 11s. It is available just up the street from me.

Yes, my original question is regarding using E85 in a street machine, not racing at all. I do agree it is not a cure-all and there are other mods that need to be made, but lowering the compression ratio to get out of detonation due to todays crap gas just raises the hair on the back of my neck. There will still be expenses - carburetor, and new pistons to RAISE the compression ratio to get good performance and improve fuel mileage has been recommended to me. That also means new rods, which I was planning on anyway. One big negative I have come across is, as has been stated in several replies, has been the varying quality of the fuel. From what I understand they mix it differently early in spring and again in fall up here in the north woods to help with starting - possibly down to 70% ethanol. More gas and less ethanol helps starting. Luckily for me, I have several stations close by that have E85 at the pump for $1.79/gal, in addition to the 87 octane at $2.49, the 91 octane at $2.92, and the 110 octane at $6.99.

Thanks for all the opinions!

Abita airport? I have had some of the Abita Amber on one of my trips to Hattiesburg - good stuff!

"...One big negative I have come across is, as has been stated in several replies, has been the varying quality of the fuel. From what I understand they mix it differently early in spring and again in fall up here in the north woods to help with starting - possibly down to 70% ethanol..."

From what I've read, it will require only a jet change, of 1 to no more than 3 sizes.

But, for those who don't wanna change jets, many of the modern EFI conversion units can use any grade of E-85.

https://butlerperformance.com/i-244...eteinline-fuel-system-fas-30402-kit.html

https://www.ebay.com/itm/FAST-30402...njection-In-Line-Fuel-Pump-/331106584093

The Holley Terminator 550-420 is also said to be E-85 compatible.

http://documents.holley.com/flyer_terminator_efi_brochure.pdf

Janeily, IMHO, do not build an engine counting on E85 to cure it's ills...and yes!...that's the Abita where they make the beer.

Oldskool, I got your point. I hope you understand mine. Peace brother.

The above links offer some interesting info....worth a read.

Here we go again. Not really what the OP was asking but morphed into a discussion about pros and cons of ethanol, bioethanol, gasanol ,what ever.
Put green or bio or eco in the description of something and some people just have to have it.
Ethanol, C2H5OH, is grain alcohol, same stuff some people mix with orange juice and drink.

While it does have a higher octane number, 109 to 97 of gasoline RON or 92 to gasoline's 86 MON, it only has about 65% the energy that gasoline does. And before you mention the big green circle around the NASCAR fuel filler with "green energy" written on it, If the corn producers gave you 100 million dollars you'd have that on your car as well. It cost money to put ethanol into fuel, you get less energy out of it, it cost more to get from point A to point B.

It does give out less emissions when you drive your car, but producing ethanol puts more greenhouse gasses into the air than does producing and burning gasoline. That and the large amounts of carbon dioxide produced and released during production doesn't make any more ecological sense than pumping oil out of the ground and refining it into gasoline, motor oil, etc. And the oil also makes other products, even makes the plastic canoes and kayaks protesters stand in when they hold up their " leave the oil in the ground" signs. Then there are the vast carbon eating rain forests Brazil and other countries have cut down to plant sugar cane, corn and other plants in order to make ethanol. Not much eco in that, but in Brazil's case they no longer have to import oil, Here we can pump it out from under us.

The economic none-sense hits me right in the gut when I go to buy a steak. Hundreds of farmers are selling corn, grain, sugar beets/cane etc. to the ethanol producers. Makes perfect sense to me, they are in the farming business and they get good money for their products. I would do the same. But the production of ethanol is subsidized by the government. That is you and I, taxpayers. It's cheaper to take oil out of existing fields and refine it than it is to make ethanol. but it's so called "green" so the government spends millions to make it. Now, for the rancher to feed the steer that was going to make my steak, he has to pay an overly priced cost for feed, thus steak goes up 300%. I say eat food and burn gas.

Ethanol absorbs water, that will lead to corrosion in your fuel system. Ethanol wears out fuel pumps. Ethanol is not compatible with older rubber seals and parts in the fuel system including senders, pumps, carburetors etc. Cars made after the eighties have ethanol resisting parts. Don't try to put it into an old outboard.
My wife's car is a 2005, everytime we fill it at a gas station that has ethanol in the fuel her check engine light comes on, it takes about three tank full of straight gas to get the light to go off. When I put it [8% here] in my bird it runs like [censored] until I can dilute it with gasoline.

If you have your car's fuel system completely switched over for E85 and have a steady source then give it a try.

We can argue the pros and cons till the cows come home but we should consider what effects it has on near 50 year old cars. Nothing good.

That is just my opinion, I'm not an expert. Nor an ecologist, geologist, chemist, economist etc.
I did not intend to offend anyone with my opinions. Being in the logging/milling business and killing trees for a living, one may think I don't give a s**t about the green earth, rainforest or any other forests for that matter, but the opposite is true. We consider trees a renewable resource just as a hay farmer does grass. And replant millions of trees a year. Just don't get me going on tree spikers, tofu, sandals, 1% milk, light beer, granola, PBS, taxes, electric self driven cars, drones, vegetarian burgers, muffler laws, the metric system, carbon tax, etc.

"...Not really what the OP was asking about..."


Really ???


OP: "...Does anyone have any experience with this?..."

I owned a Pontiac powered dirt car which was dynoed on & ran pump E-85. 755 dyno hp & ran strong & cool on the track.

And I posted links to info about others experiences with E-85. There are some guys on the PY forum who run E-85 in both street and strip Pontiacs.

But for anyone who is interested in using it, I feel that it is good for them to have all the info they'll need in order to use it successfully. So, rather than just saying it's good & lots of guys use it, I feel it is better to provide a little more info. So, if that "morphs" into more info than you wanna read, just don't read it. E-85 ain't for everybody. But, it is good for some combos in some areas of the country.

I could badmouth Holley carbs, because I prefer a Q-jet. But that would be dumb, since there are so many guys who run a Holley, with good success.

Not trying to offend anybody. Just presenting my opinion.

Oldskool,
No not really! Somehow while reading some of the posted links above I got to some posts where the argument was whether ethanol was the best thing since sliced bread and if it was going to save the planet and all living things on it. I don't know how I got to those sites, I just re read the posted links and the discusion is clearly only about the way ethanol will perform in and engine. Obviously, good or bad for the world was not where this discussion was going. It didn't morph into something else until I posted.
I like to get information and opinions from you and anyone else that posts on this site.
My mistake and I apologize to everyone.

Is this stuff similar to what you guys are discussing:

My original post was to start the discussion on using the E85 in the engine and get the opinions of all - and I appreciate getting them.

Just to clarify, I'm no tree hugger - I'm a Firebird fanatic. And I finally got one to thoroughly enjoy driving around town! I'm also a gearhead - Gimmee power - and if I can have it cheaper by using E85, bonus for me! Yes, it will burn more fuel - but in the long run, if built and tuned correctly, the overall cost per mile (as if that really matters much) should still be less. If not, oh well - it's a First Gen Firebird - it's measured in Smiles per Mile! Overall, I just don't like the idea of having to reduce my compression ratio. I like high compression ratio's, but I don't like detonation or having to add an octane booster. Building it for the E85 I am thinking will be cheaper, and I won't have to modify the heads (much). I have not yet priced things out though. I also just don't know anyone with enough experience to properly modify the heads cheap for me, I'm not going to pay $1000 each to have it done, and I don't want to use other heads. I want the original heads on the engine. That pretty much leaves me 2 options to use pump gas - dish the pistons to reduce the compression ratio (yuk) or raise the compression ratio and use E85. I think I'm going to go with the E85, just to be different.

I'm sure everyone will enjoy reading about it as you go. You will probably be the guinea pig for others if all goes well.
Keep the thread going as you work towards your goal.

"...Does anyone have any experience with this?"


There are some guys on the PY site who use E-85, and others who are considering it.

http://forums.maxperformanceinc.com/forums/showpost.php?p=5804821&postcount=30

http://forums.maxperformanceinc.com/forums/showpost.php?p=5804468&postcount=23

http://forums.maxperformanceinc.com/forums/showpost.php?p=5804188&postcount=4

http://forums.maxperformanceinc.com/forums/showpost.php?p=5804230&postcount=7

Most all the race fuel companies sell E-85 & E-98. But, their prices are way above pump E-85 prices. Cost would be well above what most would pay. I assume that you could mix in small amounts of the E-98, to raise the percentage, when pump E-85 measures only 70%.

https://www.sunocoracefuels.com/fuel/e85-r

https://vpracingfuels.com/product/c85/

https://www.renegaderacefuel.com/fuels-2/ethanol-race-fuels/

http://e98racing.com/web/

https://www.maperformance.com/products/55-gallon-drum-of-e98-ethanol-racing-fuel

http://www.igniteracingfuel.com/E-98.html

https://skspeed.com/vp-racing-fuel-x98-115-octane-pure-e98-more-consistent-than-pump-5-gallon-pail/

Torco calls theirs T85 & T98.

http://torcoracefuel.net/pro-fuels.html

I will, though it might be a while. I spent all my cash on the original purchase, and the replacement engine. I have an investment property I'm trying to sell, which when I do, it will give me the cash and the time to play with it.