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Old 12-27-2006, 07:06 AM
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350 top end re-build ?

I am new to this site and wanting to learn (I need all the help I can get).

I am going to do a top end re-build on a 1976 chevy 350ci and I need advice. It is a 4-bolt main with stock 75cc factory heads. I want to get 300+ HP, keeping it streetable and reasonable in cost. What is the best combination of heads, cam and intake/carburator ?? (or any other suggestions).

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Old 12-27-2006, 08:50 AM
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I'd go with an Edelbrock "Performer" package. It's a good all-around enhancement that won't affect driveability much. Note that you really need to replace the cam to get the power you want. Even a "Performer" cam should get you close. A 600-650 cfm carb, better intake, and a low restriction exhaust (2.5" single, 1.75"-2" if duals) will help even without a cam change. You can change the intake/carb and make the other mods without opening the engine, then change the cam later.

If you will be driving in cool/cold weather (say under 45 degrees) stay away from an "air gap" type intake. They take longer to warm up. You won't want an open air breather either -- same problem. You do want a low restriction filter element (I like AMSOIL or similar oiled foam vs. K&N -- the K&N is ruined if it gets regular oil on it, and my AMSOIL filter seems to flow as good as a K&N, or nearly so), and a large snorkel if using a factory housing.

Is this a high mileage engine? If it is, don't change the cam until you build the bottom end. The increased load on the engine will accelerate deterioration and you could have other problems. If the engine has under 100K and has always been taken care of, you should be okay with the other mos. If it's over 100K, even the bigger carb and intake will increase the load and could strain the rings, accelerating rebuild time.
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Old 12-27-2006, 02:23 PM
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350 top end re-build

Thank You farna for the advice. Can I do the things you suggested sticking with my 75cc factory heads ?
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Old 01-01-2007, 09:33 AM
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Everything farna suggested (the Edelbrock performer package and headers) will work with '76 factory heads.

The next step up would be to add GM Vortec heads from a newer 350, or similar heads from aftermarket sources. Vortec heads are 64cc chambers, and they have quite a bit better flow than the '76 vintage heads. Vortec heads require a different intake manifold, but Edelbrock and others sell Vortec manifolds for about the same price as those for stock '76 heads. Most sources show about 30 hp gain simply from the switch to Vortec heads.

If this 350 is going in a light vehicle and/or you can use a high stall torque converter, you might also look at a more aggressive cam than the Edelbrock package.

However, all of this depends on how worn the engine is in the lower end. If its an original '76 engine and has high mileage, it probably won't deal well with the additional horsepower.

Bruce
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Old 01-10-2007, 09:27 PM
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You're starting at the wrong end of the car. Put some gear in it before you start tweaking the motor.
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