3.905 pistons fit a new stock block?
08-25-2003, 03:13 PM
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3.905 pistons fit a new stock block? The bore dementions of a new stock GM block are 3.898 inches.
Many of the aftermarket piston sets are sold in the 3.905 inch size.
Question:
Do the piston manufacturors assume that you will bore your new block another .008 inches? Why? Can't you buy pistons that fit a new block?
08-25-2003, 03:24 PM
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Re: 3.905 pistons fit a new stock block? Yes you can get pistons to fit new block. The 3.905 are for old blocks being honed for fresh pistons.
Nate
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08-25-2003, 03:25 PM
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Re: 3.905 pistons fit a new stock block? 3.905 pistons will not fit a new stock block. You need to get it machined.
Diamond for example can make you 3.900 or 3.905 pistons just ask.
The default is 3.905 bore since the assumption is that you will be cleaning up the cylinders.
Diamond for example can make you 3.900 or 3.905 pistons just ask.
The default is 3.905 bore since the assumption is that you will be cleaning up the cylinders.
08-25-2003, 04:56 PM
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Re: 3.905 pistons fit a new stock block? Hey Pro Stock:
I'm likely to go with a stock based aluminum stroker short block motor using a 4.125 crank. I will re-use my SDPC ported LS6 heads milled .055 with a 60CC chamber.
Isn't it less costly and "safer" to go with a brand new GM LS1 block (as opposed to a used block honed/decked to clean up the bores)?
I assume I can clearance the block myself; is this a problem?
If #8 piston needs to be cut for reluctor ring clearance, can I request the seller of the rotating assembly to do this before shipping?
Will this impact the "balanced" assembly?
Does a dished piston of -14CC sound right to yield a 11.4 CR with these heads?
thanx....
I'm likely to go with a stock based aluminum stroker short block motor using a 4.125 crank. I will re-use my SDPC ported LS6 heads milled .055 with a 60CC chamber.
Isn't it less costly and "safer" to go with a brand new GM LS1 block (as opposed to a used block honed/decked to clean up the bores)?
I assume I can clearance the block myself; is this a problem?
If #8 piston needs to be cut for reluctor ring clearance, can I request the seller of the rotating assembly to do this before shipping?
Will this impact the "balanced" assembly?
Does a dished piston of -14CC sound right to yield a 11.4 CR with these heads?
thanx....
08-25-2003, 09:21 PM
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Re: 3.905 pistons fit a new stock block? Robert, as for the Cheaper & Safer to use a new stock block in MHO I would say NO. If you have a reputable machine shop they can machine the block using the torque plate and hone for a much nicer fit and finish than you will get from a new block. Just my .02.
08-25-2003, 11:22 PM
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Re: 3.905 pistons fit a new stock block? Chris @ Diamond can turn down pistons fitting the 3.898 holes. The rest is up to you how much do you wanna spend. There is some nasty forged 346's out which is alot easier to maintain. Cranks and resleeved blocks big $$$$. good luck
08-26-2003, 09:31 AM
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Re: 3.905 pistons fit a new stock block? If you bought a new Ls6 block from Valvegod, ~$600-650, you could just run a ball hone thru the cylinders before slapping in your stock bore pistons. If you don't have stock bore pistons then you need to get the cylinders honed out by a shop for maybe a couple hundred bux.
Robert if you are planning to run a 4.125 crank you might need to really look into that combo in terms of final compression.
My old motor was 12.2:1.
Robert if you are planning to run a 4.125 crank you might need to really look into that combo in terms of final compression.
My old motor was 12.2:1.
