picked up race motor for a street 72 chevelle,377 destroke please help

So I picked up a circle track motor for my 72 chevelle thinking I could use it for the street.  Motor is a 377 destroke and I now find myself in way over my head.  So about the motor it's got forged pistons (domed), forged H beam rods, RHS pro action or pro topline heads, Isky solid flat tappet camshaft and lifters.  Isky grind is 535-A Mech 106 degree lobe center, duration 274, 278, valve lift .534, .535, duration at .050 246, 250.  I have not yet been able to cc the heads but according to JE piston the compression on 72 cc heads would be 11.7 to 1.  I know the guy who raced it ran av gas for racing.  I am trying to figure out how to make this a streetable combo without breaking the bank.  I am only into the motor for 2 grand so I have some room to spend but I also don't want to Neuter a screaming race motor and I know it's going in a heavy car.  I don't mind buying premium fuel but I don't want to have to go to the airport for gas, I'm in colorado so where I live is at 4,500 feet or so so I can get away with some compression but I don't know how much, should I be looking at E 85, or just changing my motor, is this thing even close to streetable please help Thanks  

less lift and duration and 72cc heads and some thick gaskets at 4500 ft shouldn't be too awful bad. I don't think you'll have to stop by the airport for gas (your heads are aluminum aren't they?).  

Did you take it pan off, and atleast check the bearing clearances? A Race engine is built for abuse. Throw the valve springs away.

You can decam the engine. Go with something with a .465 lift and duration @.050 at .224 to 230. Max. Make sure you change the valve springs. In a heavy car stay around .214 to .218 dur. @.050 lift at .450. all with a 1.5 rocker ratio.

The compression is probably up there. You can have the domes machined off, or replace the pistons with a flat top 2 or 4 eyebrow type.

In general I would go through the engine. Replace the bearings, rings,  pistons machine dome off or replace?  Replace the Cam, and valve springs to match.

Bob AKA pepsi1  

OK, purely out of curiosity what kind of power loss should I see by reducing compression, and no Z man they are iron heads.  I know I probably need to do it I just can't help but feeling like I'm ruining a good race engine.  And no, I haven't checked the bearing clearances, I know this motor has been run but not since it's been rebuilt but that's a good call I never thought of it. As I said I came across a good deal on this motor and kinda jumped and then I figured out I was in the deep end.  

First, please let me clarify something. Airplane or "aviation fuel" is a oil base and runs on compression and not spark. Maybe a 104 to a118 octane is what was run in the engine. Second, a 377 makes a great road or dirt track engine due to the high RPMs that engine is capable of turning. I myself would not change a thing. If you burn pump gas I think you will be OK, but nothing wrong with burning 118 octane it will keep engine clean.  

Robert, your last post confused me. ALL gas comes from oil. Diesel runs on compression. Airplanes have spark plugs..Jet engines run on jet fuel which is a type of fuel oil like diesel.  

sorry for the confusion, piston engine airplanes have spark plugs, jets do not.  

That's true diesels run on compression unlike our regular car and piston airplane engines that have spark plugs. Diesels do have a plug of sorts but it is more of a glow plug than a spark plug and it is used mainly to start the engine when cold.
Trying to run a race motor in a daily driver is going to be a compromise at best.
You may be able to run 100 octane gas, we have it available here locally in Knoxville Tn., with that combo of almost 12-1. The long duration cam should give you lower cylinder pressure at lower speeds to help avoid detonation.
I ran a 50-50 mix of 110 octane race gas and 93 octane in a 14-1 race motor with no problems.
If you are running this daily you are not going to like it much. It is going to cost you a lot to run a car that gets maybe 7 mpg. It also wants a lot of rpms to make its power. It will not be happy running at 2000 rpms.
I think saving this engine for your next race car is the answer. You will take all the fun out of it if you detune it to run like a granma engine.
However if this is just a Sunday car or it will be mainly a strip car, where race gas is usually available, then by all means put it in and have fun. Don't detune it at all.  
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To much work put into it to take away any potential great running engine  

definitely only a toy to play with, not a daily driver, do you guys think this is something usable on the street if i'm not counting on it all the time, or is it still too radical.  talked to the guy who built it today he said the powerband is 2800-8000.  I will be running a muncie 4 speed and at least for now 373 posi rear. Also cc'd the heads today and they are 72 so compression is probably between 11.7 to 1 and 12 to 1.  

If it is just a weekend warrior leave the motor alone. You will need a little more rear end gear to take advantage of that high winder as low speed torque is going to be weak.
If you have a drag strip nearby you could pick up your race gas there and mix it 50-50 with 93 and be able to run that 12-1 ocmpression as long as you don't juice it.  
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Unless your going to run it the way it is, it's probably not going to be worth detuning it. Put it on craigslist and pray...  

so, thank you all for the advice, I believe I'm going to just drop it in and run it, I just can't bring myself to detune it.  After takling to the motr builder however, I still have a couple more questions.  He says he ran this motor with a 1000 cfm carb. And maybe that was fine for circle track but I just can't a imagine a small block requiring that, so where do you all think I should start maybe an 800 demon casrb or a 770 street avenger?  Also, this thing has a super victor single plane intake, if I'm giong to street it should I be looking for a dual plane or just leave it be and see how it runs ?  once again thanks for the advice you all are life savers  

1000 is a little large for this motor but I would put it in as is and have some fun with it. Your low speed will suffer some with it but you could always change it later if necessary.  
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A bare bones '72 Chevelle weighs about 3200 pounds, add a driver, gas etc and we are close to 3500#
The engine will idle around 1500 RPM, so a loose converter is a must.
Rear end gearing with 3.9's or 4.10's should make it "almost" streetable.
There will be little manifold vacuum for brakes.
Good tuning skills will be needed.
Best of luck and enjoy the engine.
A 750 carb would be my choice for the street.

 
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