short deck
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short deck I tried posting to the regular forum with no bites.
How much can the aluminum block deck be shaved? Assume I'm putting in custom length rods, custom compression height pistons and I will have a custom intake manifold. I would like to lower the deck a lot. Can I do .020? .200? .500?
I have a cutaway picture of a block and it looks like there is about 3/8" meat before hitting the coolant passage.
Surely someone on this forum has a bare block they can look at and measure or a bad block they can cut up
Randy
How much can the aluminum block deck be shaved? Assume I'm putting in custom length rods, custom compression height pistons and I will have a custom intake manifold. I would like to lower the deck a lot. Can I do .020? .200? .500?
I have a cutaway picture of a block and it looks like there is about 3/8" meat before hitting the coolant passage.
Surely someone on this forum has a bare block they can look at and measure or a bad block they can cut up
Randy
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Originally Posted by Nine Ball
Randy, I'm curious about why you would want to chop the deck down so much? Most shops just do a clean-up pass on the deck, to get a smooth surface.
If there is enought meat I'd like to shave about 1/2" but I suspect there isn't.
Let me know.
Thanks,
Randy
Last edited by RandyS; Oct 19, 2005 at 09:55 AM.
Originally Posted by RandyS
I need a low deck height for race engine I'm thinking about. It will be a 511ci (4.8 crank and 5.7 block) to meet the rules.
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Originally Posted by DAPSUPRSLO
4.8 crank, how is that going to work in an ls1. wow, that sounds interesting, good luck
Last edited by RandyS; Oct 19, 2005 at 09:52 AM.
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Verdad Gallardo I'm not a machinist nor a professional engine builder so I have no idea if it will work or not. I just know that a 4.25" is about the biggest I've heard of. I would not think you would be shortening the deck with that big of a stroke, if anything I would think you'd want to add to it to fit in the proper rod to maintain some kind of rod to stroke ratio. Like I said I'm no professional and that is only a guess from seeing looking at other's combonations. Good luck, that should be pretty interesting.
you know what, I just realized you menat the crank from the 4.8 litre motor, never mind, ha ha. I thought you meant a 4.8" stroke.
you know what, I just realized you menat the crank from the 4.8 litre motor, never mind, ha ha. I thought you meant a 4.8" stroke.
Deck milling Randy,
I measured one of my machined for MID sleeve blocks for you to see how thick the deck is. Measurements run between a minimum of .400" and a maximum thickness of .450".
I wouldn't take any more than .020" off the block. Much less than .400" causes gasket sealing issues.
Steve
I measured one of my machined for MID sleeve blocks for you to see how thick the deck is. Measurements run between a minimum of .400" and a maximum thickness of .450".
I wouldn't take any more than .020" off the block. Much less than .400" causes gasket sealing issues.
Steve
Originally Posted by RandyS
I tried posting to the regular forum with no bites.
How much can the aluminum block deck be shaved? Assume I'm putting in custom length rods, custom compression height pistons and I will have a custom intake manifold. I would like to lower the deck a lot. Can I do .020? .200? .500?
I have a cutaway picture of a block and it looks like there is about 3/8" meat before hitting the coolant passage.
Surely someone on this forum has a bare block they can look at and measure or a bad block they can cut up
Randy
How much can the aluminum block deck be shaved? Assume I'm putting in custom length rods, custom compression height pistons and I will have a custom intake manifold. I would like to lower the deck a lot. Can I do .020? .200? .500?
I have a cutaway picture of a block and it looks like there is about 3/8" meat before hitting the coolant passage.
Surely someone on this forum has a bare block they can look at and measure or a bad block they can cut up
Randy
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Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
8 Sec Tuner
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From: Wish I was in a boat fishing...
Originally Posted by Nine Ball
Randy, I'm curious about why you would want to chop the deck down so much? Most shops just do a clean-up pass on the deck, to get a smooth surface.
-Ben
Norm Brandes from Westech Auto in WI built a 311ci engine for a Camaro show car for GM about five years ago. Motor was a 5.7 block with a 4.8 crank.
Anyway I would avoid majorly decking the block because the complications from changing the geometry far outweigh the downside of the rod size you are talking about IMHO.
I looked at doing this a while ago, even had a 4.8 crank, and I thought it was possible for me to run a 6.250 rod with custom pistons.
Anyway I would avoid majorly decking the block because the complications from changing the geometry far outweigh the downside of the rod size you are talking about IMHO.
I looked at doing this a while ago, even had a 4.8 crank, and I thought it was possible for me to run a 6.250 rod with custom pistons.
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Thanks all.
A couple of years ago I heard a rumor that GM was considering casting a 8.5" short deck LSx version for use in FWD cars. Factory displacement range was supposed to be 4.2-5.1 liters.
Now that the Grand Prix/SS comes with the regular deck 5.3 and GM is on the verge of chapter 11 I guess it got shelved.
I could always have the deck cut and welded but too much effort for me.
Back to the drawing board.
Randy
A couple of years ago I heard a rumor that GM was considering casting a 8.5" short deck LSx version for use in FWD cars. Factory displacement range was supposed to be 4.2-5.1 liters.
Now that the Grand Prix/SS comes with the regular deck 5.3 and GM is on the verge of chapter 11 I guess it got shelved.
I could always have the deck cut and welded but too much effort for me.
Back to the drawing board.
Randy
Don't worry too much about it Randy... I get why you want to do it and I like it but just throw some rod length in there and call it good. Or just go run a short deck SBC (lots of $$$$) or a 302/5.0L block.
Bret
Bret
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From: Odessa, TX
That rod ratio is a bunch of crap IMHO. I have seen guys spend hundreds of thousands of dollars getting the right ratio and to many other variables help show power. My example is this: A pretty known name shop in extreme high performance told me that it matter more than ever and was worth about 40 horsepower on a NHRA pro stock truck engine. They took and engine that made 880 hp and did nothing but change the the rod ratio and new pistons with a tall compression height. Re assambled the engine and it made 920. He replyed to me that was even with a heavier piston. I think that the motor made more power because it had the tall compression height and stablized the piston in the bore keeping the rings sealed better in the engine at higher rpms. The magic number in rod ratio is 1.67 in some peoples mind. If the rod ratio works so well than how come the 302 ford is such a piece of s--t.
5.090/3.00 = 1.697 Look all you want and you will never find it there. I buiding a 311ci (4.060x3.00) C-5R headed LSX motor right now and our main goal is compression and head flow. If you use a stock head you need to be worried more about the compression than anything.
5.090/3.00 = 1.697 Look all you want and you will never find it there. I buiding a 311ci (4.060x3.00) C-5R headed LSX motor right now and our main goal is compression and head flow. If you use a stock head you need to be worried more about the compression than anything.