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What are you looking for? Power, economy, or a little of both? If it were me, I'd build a low compression (9:1) 400 for it. I'm getting good power and excellent fuel economy from a low compression, moderately cammed 400 in my '67 GTO. Are you going to race the car, or just cruise it? Daily driver or weekend warrior?
 

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best bet is going to be a 400 like GeeTee said, it can go anywhere from mild stock build to stroked 462 500+ hp. blocks are readily available and the strongest of the bunch.
 

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Well you live in Vegas, or near it. You have 20 pumps in town that carry E85 which runs much cooler in the heat and makes lots of power, along with being cheaper than gas. Your engine will also last longer on it, and if you up the compression you can get pretty good mileage on it. I will find out how good you can do later this summer with my 70.

So I would build a stroked 400 or a 455 with ported/milled 72 cc heads, a mild cam that makes great power down low, stock intake, and send me a Qjet with a rebuild kit and I will convert it for you free of charge. You can build one of these cheap, make lots of power, and do pretty well on fuel and not ever have to worry about if you have good enough gas to make it run in the heat with anything over 8:1 compression. Just because it has between 11:1 and 14:1 doesnt mean you need a huge cam so it doesnt have to be incredibly thirsty. Man do they sound nice with lots of squeeze running on ethanol.
 

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:agree with Thumpin'. If you know you're always going to be driving the car where you have E85 available, then the idea of building a high-compession "alcohol" motor has a lot going for it if you're after power. My personal favorite would be a 400 block stroked to 460+ because you get the benefits of the cubic inches without the drawbacks of the larger main journals/weaker main webs in the block. "Fuel economy" is a relative term when it comes to these cars, and I personally have no experience with alcohol motors - but Thumpin' does and is probably the best authority on them around here in terms of how to build one and what to expect. I've "heard" that alcohol has less "energy" in it per unit volume so it takes more of it to get the same power as gasoline, and that has an effect on fuel consumption when you're running at max power ---- but how it affects "normal" operation I haven't a clue.

Is that right, Thumpin?

Bear
 

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Bear88, my realatively heavy '67 GTO ragtop with TH400 (no overdrive or lockup converter) gets a little over 20mpg at a steady 70-75MPH. The secret is a light foot and the 2.56 gear I slipped into the back. With the low compression 87cc heads, it does not run as hard as it did back in the early '80's, when it was still wearing it's high compression heads, but it runs well. The secret these days with running lower, pump gas friendly engines is to install a modern grind camshaft (like the Comp Cams XE series) that fills the cylinders better and makes up for lost compression by superior flow. Recently did a low compression 389 for a friend, and his car runs as hard as the high compression race-gas job in my own '65 GTO. The alcohol thing may be an option, too. I have zero knowledge of alcohol motors, but there is no E-85 available here where I live. I could not have an E-85 car, because I like to drive them cross-country and need fuel that is available everywhere. Have driven the '67 to Yellowstone, Grand Canyon, etc. If you are going to stick to driving locally, an E-85 build may be the ticket. Again, it's up to you. Me, I'd build a low compression 400 with a comp cams XE262 cam and install a nice q-jet intake and q-jet and a good exhaust system. Cheap and effective. The most common rear gear in the '65 LeMans seems to be about a 2.78, so you'll be all set for good economy, combined with the tiny primaries the Q-jet has.
 

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E85 pumps are going in all over, new ones every week at least. Its thin in some areas, but not in LV with 20 pumps. California is finally growing, they were held back by CARB and the people running CARB who had oil and coal interests. Really. Its coming to where it isnt, and where it is we can use it. We dont have to, but its available and you never have to worry about having enough octane not to ping. I still have to drive 21 miles to get E85 since there is only one station near here with it, it would be awesome to have so many pumps so close to me like he does.

The BTU content is lower, but BTU is a measurement of how long it takes to heat one gallon of water. We arent heating water with an engine, we want it to do work and make power. Gasoline does a nice job heating water, even in an engine it heats things so much instead of powering the vehicle that we need large radiators to suck the heat out. Ethanol burns faster and cleaner heating the parts less that means more of it goes to actual work than waste heat. You also have the added benefit not fouling the engine and oil with black carbon, its kinda nice since oil changes can be much less frequent and you dont have nearly as much internal wear and crud building up in there. the lack of heat build up in Las Vegas is a huge bonus, if you want to make lots of power and not lose it when it gets really hot, ethanol is the way to go. It is affected much less by ambient temperatures than gas engines.

The reason why you need to run more fuel through the carb or injectors is simple. Ethanol is an oxygenated fuel meaning it has its own oxygen, so you need less air to make the same power as gas. Since the ports, valves, carbs, and everything else is designed to ingest air for gas, its all too big for the same power level. So you need more fuel since you are getting some air in the fuel. The hot air in Las Vegas will actually help him get better mileage with ethanol, where it would make it run worse with gasoline. I can explain that later if you guys want to know how.

All of this translates to you will produce more power, it will drive better, not fall off in the heat, wont overheat nearly as easy if at all, the engine will last longer from less black grit in it and less heat in the parts, and you can make lots of street power with it because of the compression. It is very easy to work with, very easy to tune, and wont hurt anything on the car right now.

The bonus is if you send me a Qjet and a kit, I will rebuild it, make it run on my engines with E85, and ship it back to you free of charge. I do it because it is fun for me, and I want people to see how nice it is to run E85 in their GTO. I dont make any money from doing this, I do it because it is a good fuel and it is easy to work with.

You can always build an engine with low compression and send me a carb to try out. It will still run great with even 7:1 compression, and all it takes is a carb swap and drain the tank if you dont like the power you get, or if you want to make a long road trip to California or one of the other states without many pumps. Thing is I know you will want more compression to get better mileage and power after you bolt the carb on and fill the tank with ethanol. I know I did after I built a 700hp E headed 467 that will run on 92 pump gas. I wish I had built more compression in it, I could make the same power with a smaller cam and have it more fun to drive.

You know though, this is all my opinion of what I would do if I lived there and had a blank slate to build an engine. You dont have to, its just something you could do.
 

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Discussion Starter #12
Im very interested but i have no knowledge about running E85 but sounds like a great option... Since you have it in your car if you dont mind me asking what did it cost you to get your set up???
 

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It cost me a carb rebuild kit, some numbered drill bits, and some time figuring it out. So less than $200 because the drill bits were $90. I convert them myself, and I like the Qjet quite a bit but a Holley will work too. I have been thinking about converting an Edelbrock carb since I have two of them sitting here, but I like the Holley and Qjet much more.

It is just like rebuilding a Qjet per Cliff Ruggles book, except you open some of it up more to flow more fuel at idle and through the main/secondary circuits. Like I said, send me a Qjet and one of Cliffs kits with a .150 needle seat assembly and I will do it for free. A Holley is easier than a Qjet to convert as long as the boosters dont need swapped, you just open up certain passages in the metering blocks with numbered drill bits.

I cant charge anything even if I wanted to, but I can help a friend out so that is why I do it. The VA has rules and limitations about me making money, so its easier if I just dont charge anyone for little stuff like this. I enjoy doing the work and it is fun for me to take something that is junk and rebuild it so it works, keeps my mind and hands busy so its good therapy, why charge someone for my therapy?
 

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hey Thumpin are you able to do the holleys i have a 750 with a re-build kit for the 455 and have been thinking of running the E-85 as its at all the Meijers gas stations downstate.
 

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Yeah I can do them too, they are easy and run pretty well. You have it all over down there too, I wish the UP would get more stations, particularly in Marquette. Pick up a rebuild kit and send them up to me.
 

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A 400 Pontiac will bolt to any BOP (Buick-Olds-Pontiac) trans, so ST300 two speed, Th350/Th400 three speeds, 2004R four speed overdrive, and with an adapter a 700R4 overdrive will fit. Any of them can be found relatively easy, and they are simple to swap between them for the most part.

I am putting a 700R4 behind the 455 going in my 70, the 65 is getting a 400 with a 2004R, and I have run Th400s behind everything at some point. A Th400 is what is in my drag car and the HO Formula, they are almost bulletproof.

You can also put in four speeds (M20-M21-M22) and three speeds with the right bellhousing. With some floor mods you can install TKO 500 and TKO 600 overdrive manual transmissions. They run a bit under $3k for everything.
 

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Thumpin,
My 65 GTO has a 455 with the Edlebrock heads. Running 3-2's and am interested in this as the compression is right up there. Much have to be done to the 3-2's?

rich
 

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Most of the work would have to be done to the center carb since it has the idle circuits and transition circuit. The end two would only have to flow more fuel through the main circuit. So that means the center carb would be somewhat harder to convert, and you might be able to just put larger jets in the ends. The float levels need to be adjusted in all of them, but the end carbs are less complex than the center.

If you have an extra 2 barrel Rochester carb laying around, I would be more than happy to find out what it takes to make them run on E85. Im not sure I have one anymore, but a call to one of my friends back home to see if he has one might fix that. The idea of a tri-power running E85 is very intriguing and I would enjoy converting one, but I dont have any of the tri-power parts.
 

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I will start the search for one, or buy a copy one from PY . I will let you know. I am running a 66 setup for the bigger center.
I know of one E85 down near Boston, and am going to do my research to find ones in my back yard.
I will let you know what I find.

Thank,
rich

Happy Forth to our country and to all!
 
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