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Let me start out by saying that I am really frustrated, and any opinions are welcome and appreciated.

Yesterday, I had complete, running drivetrain. Today I have a pile of "worthless" parts.

The engine that came in my newly-purchased '70 fastback is a completely stock, rebuilt 351W from one of the big car parts chains (Autozone, NAPA, etc). Weiand Stealth intake, Edelbrock 600. I figured new heads (Edlebrock RPMs), a new cam, bigger carb, and for about $1700 I had a great motor.

My engine guys, on the other hand, came up with a $3800 shopping list for me. I laughed. We went back and forth, and finally he said, "lets take off a head and see what it's like inside." We pulled the motor, tore it apart, and discovered that the rebuilt shortblock is brand spanking new. This engine has NO wear since the rebuild! Sounds like a perfect candidate to me!

Then he pulls out his guages. .060 over. He says no way, the block is junk, too weak for the mods I want to do. Tells me that all the internals are cheap and unreliable. This will be a road-racing track car (Boss Trans Am replica), so higher revs for a long duration, but not the rough abuse of a 1/4 mile car.

What do I do? Leave the short block as is, and install the performance parts? Install hypereutectic pistons? Junk the whole shortblock because it will never withstand the power? Of course, I want it to be reliable, fast, and cheap. I want ALL THREE! ::

Next week he's going to do some sonic test to see if the overbored block is strong. :: What would YOU do? Thanks, Max
 

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What year is the block? If cheap is what you want then you already have a motor that's paid for. Unless you could sell it to off set the cosat of a new build I would just run it as is with your mods. Of course it would depend on what kind of power are you looking for? Based on the heads and the other items listed I would say your bottom end will be fine.
 

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That's exactly why I would never but a crate motor from a chain store, you never know exactly what you are getting. But then again, I'm a mechanic by trade and build my own engines.
 

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I would do the sonic check to verify that there are no known weak spots...but for the price, I would then do the mods and run it till it lets go.....
 

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This will be a road-racing track car (Boss Trans Am replica), so higher revs for a long duration, but not the rough abuse of a 1/4 mile car.

Not sure where you get your information......but high revs for long periods of time are just about the harshest environment an engine can endure.
 

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A generic rebuild will probably do just fine with some minor performance mods. However, there is NO WAY you are going to turn 6500 rpm for hours at a time with it. Something in the short block is going to break.

Engines for road racing need to be specially built so that they have no weak spots - and that cost $$$$. Oiling, rods, pistons, rod bolts, balance, valve train, bearings, etc. all have to be just so. An engine is only as strong as its weakest part.
 
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