Maximum bore on the LT1?
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St. Jude Donor '03-'04
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Maximum bore on the LT1?
Assumption 1: The LT1 block is aluminum with iron liners
Is this correct?
And, if it is, what is the largest overbore size anyone has ever heard of on the cylinders? What can she take afore she 'splodes? Can an LT1 become a 400-422 like the LS1 block?
~Matt
Is this correct?
And, if it is, what is the largest overbore size anyone has ever heard of on the cylinders? What can she take afore she 'splodes? Can an LT1 become a 400-422 like the LS1 block?
~Matt
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From: Toronto, Canada
Re: Maximum bore on the LT1? (Matt Black)
The LT1 block is not aluminum and does not require sleeving like LS1 motors. You can safely build a 396ci motor(4.03 bore x 3.875 stroke) and make plenty of power. A few people have built 421ci LT1 motors, but it takes a lot of skill and dollars. Hop on over to camaroz28.com and look for Mark Montavalo he has built 2 big cube strokers and would be able do give some more details.
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From: Athens AL
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Re: Maximum bore on the LT1? (95vettski)
LT1 is not AL. LT5, LS1/6 are aluminum.
I wouldnt go more than 396ci.
I wouldnt go more than 396ci.
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From: Guinness Its whats for B'fast JAWGA
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Re: Maximum bore on the LT1? (vader86)
General rule is 40 over but 90 over has been done. The biggest economical LT1 is the 396 .030 over with a 3.875 stroke. The block has to be sonic checked for the big bore over .040. MarkM who posts on CamaroZ28.com built a 421 with a .090 over. http://www.c-zone.net/montalvo/LT4_4...ifications.xls
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From: Sachse Texas
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Re: Maximum bore on the LT1? (93Polo)
I wanted to go .060 with my block the last build and my engine builder recommended against it as my block did not have thick enough bore walls to handle my nitrous in addition to the NA power. I ended up at +.040.
There are those using a 4" stroke crank to get the 409 or 421 motors, but that is a lot of block work to make them work.
There are those using a 4" stroke crank to get the 409 or 421 motors, but that is a lot of block work to make them work.
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Re: Maximum bore on the LT1? (93Polo)
General rule is 40 over but 90 over has been done. The biggest economical LT1 is the 396 .030 over with a 3.875 stroke. The block has to be sonic checked for the big bore over .040. MarkM who posts on CamaroZ28.com built a 421 with a .090 over. http://www.c-zone.net/montalvo/LT4_4...ifications.xls
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St. Jude Donor '03-'04
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Re: Maximum bore on the LT1? (BrianCunningham)
Well ain't that just spiffy. Crud, here I've been thinking this whole time that the LT1 block was aluminum.
Okay, next question, who makes a really good aluminum small block Chevy casting that will go into a C4 engine bay without having to do a boatload of mods to the engine mounts? Heh....with the C5R block fit?
Or, where is a good place to get an LT1 block that's been ultrasonicated, penetrant tested, and perhaps even x-rayed to determine that it is a true quality block?
This is a long-term project for me, and I'll be willing to shell out dollars for great components...
Okay, next question, who makes a really good aluminum small block Chevy casting that will go into a C4 engine bay without having to do a boatload of mods to the engine mounts? Heh....with the C5R block fit?
Or, where is a good place to get an LT1 block that's been ultrasonicated, penetrant tested, and perhaps even x-rayed to determine that it is a true quality block?
This is a long-term project for me, and I'll be willing to shell out dollars for great components...
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Re: Maximum bore on the LT1? (Matt Black)
I would'nt even bother with a 396ci, go with a 383ci...13 cubes is worth maybe 5-10hp if that, and you'll spend alot more for the pistons on a 396ci, a 383 is a very common setup and pistons are usually alot cheaper, the crank will be less on the 383 also... some also belive the rod angle on the 396 to be a bit awkward causing other issues, plus if your going with a 6'' rod on the 396 the pin hole will be up into the ring area causing a weaker piston, if you ever decided to use NOS that would be a problem too..
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Thread Starter
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St. Jude Donor '03-'04
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Re: Maximum bore on the LT1? (JB'S LT4)
I'm thinking more in the nature of a mid-cube upgrade and then a supercharger. Supercharged 383 sounds interesting...
Racer
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From: Austin, Tx
Re: Maximum bore on the LT1? (JB'S LT4)
I've seen the horsepower differences and in some cases there is only 10-15hp to be gained at peak.... BUT if you look at the dyno graph (horsepower and torque), the 396 is putting ALOT more area underneath... which equates to a quicker car.
Sorry, just had to put that in. These turbo guys think they're bad because of their peak horsepower/torque #'s. Too bad their graphs look like a 45 degree angle :) !
Sorry, just had to put that in. These turbo guys think they're bad because of their peak horsepower/torque #'s. Too bad their graphs look like a 45 degree angle :) !
