LS1 vs LQ9

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Dec 9, 2012 | 01:17 PM

#21

93Z2871805

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Quote:

Originally Posted by Blackpanther99

Im just saying beacause that what my project is gonna consist of. A 6.0 Bored to a 427 stroker with forged internals and low compression pistons (or normal pistons in your case if you want a N/A setup)

why a 427? The 4.125 stroke seems pretty big, and a 4.060 doesn't leave you much cylinder wall. Why not a 408 or a 418? I'm assuming by the low compression pistons you want to go FI correct?

Dec 9, 2012 | 03:16 PM

#22

Blackpanther99

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Quote:

Originally Posted by 93Z2871805

why a 427? The 4.125 stroke seems pretty big, and a 4.060 doesn't leave you much cylinder wall. Why not a 408 or a 418? I'm assuming by the low compression pistons you want to go FI correct?

Yes I am going to do a FI setup, its not the walls I have to worry about, I have to worry more about my low compression pistons and my crankshaft. To fit in a standard deck block, they typically have a compression height of about 1.0x" which is relatively thin and flimsy. Not to mention, the rings are exposed to even more heat since they will be moved further up closer to the point of combustion in the cylinder.

Dec 9, 2012 | 03:31 PM

#23

KingPin1094

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From: OH

Whats this thing with Fly cutting? I am completely knew to the LQ9. as far as i know it is an iron LS2. Please enlighten me.

Dec 9, 2012 | 04:28 PM

#24

badazz81z28

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Quote:

Originally Posted by KingPin1094

Whats this thing with Fly cutting? I am completely knew to the LQ9. as far as i know it is an iron LS2. Please enlighten me.

"Fly cutting" is cutting the pistons to gain clearence for the valves. They look like little eye brows...I have no idea where the name origonated.

Dec 9, 2012 | 04:31 PM

#25

badazz81z28

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For the record...I don't like the idea of fly cutting...Thats why they make pistons with valve reliefs already casted into them. I would opts for a few less ponies (Smaller Cam) than mess with that.

Dec 9, 2012 | 04:45 PM

#26

R6cowboy

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Quote:

Originally Posted by badazz81z28

For the record...I don't like the idea of fly cutting...Thats why they make pistons with valve reliefs already casted into them. I would opts for a few less ponies (Smaller Cam) than mess with that.

The idea may scare some. As long as its done correctly and not too deep, it shouldn't do any harm to the piston(s) nor should it cause a piston to fail.

Dec 9, 2012 | 07:00 PM

#27

KingPin1094

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From: OH

Oh. Okay yea for my 496bbc i built i just bought HC pistons with valve reliefs. Did not know that process was called fly cutting.

Dec 10, 2012 | 04:44 PM

#28

93Z2871805

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Quote:

Originally Posted by Blackpanther99

Good points (on a 6.1 rod that's a 1.0775 compression height and a bore/stroke ratio of 1.033. I can imagine there's a little bit of clearancing too as well as having the skirts of the pistons grooved for the counterweights and the potential for piston rock at BDC), so, why do it? Why not a 408 (or even a 398 or a 370) or go with an LSX block?