8 MPG?

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Vbb199

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Not since 1970 when Canada converted to the metric system. So, it's still about 70% of the American.

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@shiftpro you're 70% average [emoji23]

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MisterB

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Man, back on topic gents.

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MikeB

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Factory rebuilt engines are no better and that's twice the sin as it did had two chances to get done correctly.
IMO without a nice tight squished quench zone height (I just had too!) you have NOTHING and all the parts and cam you throw at will only gain a fraction of what's really available.
You want 20 mpg out of a 350...? Start here.
Well said, and funny!
 

MikeB

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Best part was seeing the look on some rich punk daddy-bought-me-my-car face as a lifted truck smoked them in the 1/4. 13.2 to 13.3 on average. I grinned a lot :D

I guess that's why I had to feather foot a lot to payday. lol

:D:D:D
 

MikeB

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Just so I understand what you are saying, the distance from the top of the piston to the mating surface of the head when installed should be .040 to .045?

If correct what compression ratio would that produce with 64 cc heads?

Correct! For a 350, compression with 64cc heads and .043" quench height would be anywhere from 10.0:1 with flat tops (with 4 valves reliefs) to 9.4:1 for a Speed Pro hyper-eutectic with 12cc dish to around 9.0:1 - 9.2:1 for a stock type piston. (I don't recall the dish size, so I'm guessing.)

Keep in mind that some aftermarket pistons are "shorter" (lower compression height) than stock pistons to accommodate severe block surface machining (decking).
 

MisterB

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I decided to connect the vacuum gauge to the very back of the carb in the large port in the middle that was plugged. It was still in that red zone, so I adjusted the idle and also lean/rich and as you can see I got it up in the green zone. Time will tell, but so far the truck seems to run really well
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