zjet

060. bore on a lt-1 isn't a big deal . depends on the block,have it checked before boring it.I did a 388 with no problems it's all in the block.

If cub's is your goal change to gen 1 and use a dart little m has a max bore of 4.155. There's a 96 ss in town the guy used a dart block on and did a 427 using a tpis mini ram for the f/i.With a fast system for a computer.

PNYKILR

I'm .040 over on my 396 with no problems. You can do .060 but you'd be pushing it.

Neal

Elysian

I actually have a gen 1 400 block. I purchased it a LONG time ago before I knew there was a difference between gen 1 and gen 2's. It has 4-bolt splayed mains, has been align honed, etc. It last ran as a 421ci, and when I bought it I was told it oculd be bored out to a 440 ci. If aftermarket fuel injection systems were a little cheaper (or my LT1 setup could be converted over) I would consider doing it. Only thing is, I have about $2500 into some AFR LT4 heads that are already on the car. If I was going to go the Gen 1 route, I'd get a kickass set of 12 or 15 degree heads flowing in the 380cfm range. That would probably be a nice way to shut up the LS1 crowd (newer isn't always better), but there's no particularly cheap way of getting there. I would need a crank, pistons, cam, heads, fuel injection, etc. Another thing I'm not sure of is whether or not my T-56 would bolt up. Has anyone converted an LT1 fuel injection setup over to a gen 1 block? Looking at the front of the block (the optispark and what not), it seems like there would be some compatibility issues. ???

Highlander

http://web.camaross.com/forums/showt...7&pagenumber=2

In this thread chad has a 427 ???

Anyways... I think that if you bolt the lt4 heads on you can use the fuel injection as the cam and front cover is all teh same thing.. although no retrocooling... I believe the block has different passages.

dhirocz

I've got it done on paper. Gotta do some machine work to the LT1 cover to make room for an adapter plate to use an LT1 timing cover and have it actually spaced right. Then some minor clearancing work needs to be done in the block itself if you plan on running an LT1 waterpump with adapters. Sounds like alot of work, but it's the only way to safely run over 400ci with LT1 fuel injection. I'm gonna try it on my 400 when I get some time.

What the aftermarket needs to do is offer an affordable block with at least a 4.125" bore, stroker clearanced, for roller 1pc. RMS engines in standard and LT1 configuration. That would ROCK!

As far as the heads, they can be easily converted to LT1, or vice versa. I have ported LT1 heads converted to gen I on my 383...cheap, made with good parts and small chambers with the LT1 intake bolting right on!

I dont know why so many people are in a hurry to bore their engines. The last several 350 based engines I've built had no overbore whatsoever...the blocks mike'd out perfect and they didn't need it. You sacrifice strength whenever you bore. My 383 has a standard bore as well (block is nearly new) with a 3.80 inch stroke (also 383 ci)...the crank is forged and the bores are std., so it's perfect for boost...

just my $.02

rskrause

I agreee. Definitely with boost or N2O as little overbore as possible on a production block. For NA, it depends who you believe. Some people say the minimum cylinder thickness should be 0.140", others want 0.170". Remember that once you go out that far, that will be the last overbore you can do and save the block. If you want to go over 0.030", get it sonic checked to avoid a problem. A partial fill will help if the cylinders are marginal. You need to decide if you are building a time bomb or a motor.

Rich Krause

Highlander

Hey rich... i might need a .040 now... would that be a bad idea for a 700rwhp engine or should I get a new block?

I have a block laying around but it would require a lot of $ in machining to get it to 4 bolt mains, clearance and the such... Let me know what you think is the best option.

Thanks

rskrause

I you have someone who can sonic check it, that's ideal. I ran my last one 40 over and it was ok.

Rich