litch2004

iTrader: (1)

Well my 93 T/A just hit 169k and im about to pull my engine to replace the front and rear main seal. I plan on sending my heads and intake in for a LE3 package. What is the amount of bore needed to be able to run this package?


Also i have built 383s on regular 350s but never messed with an LT1 before. Is it the same principle? 400 crank and all? And Ive been seeing people with 396 what all did you have to do to get that ci? any help will be appriciated.

fergymoto

iTrader: (129)

There's no reason you can't run it on a 350. Lots of people running heads/cam packages on stock short blocks.

A 400 crank will not work in a LT1 being 2 piece seal. You'll need a 3.75" stroke crank for a 1 piece seal small block.

litch2004

iTrader: (1)

o ok. What is the biggest bore i can go with?

litch2004

iTrader: (1)

and from what i have heard the LE3 heads will hit and it at least has to be bored to 355

litch2004

iTrader: (1)

bump+

OutlawZ

iTrader: (4)

Hit what???? Ok i'm going to try and correct some misinformation that you have been told.... First off the LT1 is a 350 cubic inch block with a 4.000" bore and a 3.48" stroke 1 piece rear main seal crank. 5.7" rods are stock which has no impact on cubic inches.... So 350 ci = 4.000" bore and 3.48" stroke..... A 355 is simply a 4.030 (or a .030 overbore) with a 3.48" crank (ie stock or forged but 3.48" stroke) rod choices for a 355 are usually 5.7", 5.85", or 6.00" with 6" usually being the best choice....

A 383 LT1 is not a 400 crank. It's a 3.75" stroker crank combined with the .030 overbore for a 4.030" bore.... Once again rod choices abound with 5.85" usually being the norm but 6" rod 383's are not impossible... (I'm building one).... When you lengthen the rod you have to change the pistons structure so that the wristpin of the piston is taken up into the piston to compensate for the added length. If not your piston would come up and come out the bore at top dead center..... also block clearancing is required to clear rod bolts...

A 396 is a 3.875" crank with a 4.030 bore (once again a .030 overbore from stock).... more clearancing is required to clear rod bolts cause of the larger stroke. rod choices again are plentiful....

All of these motors see require a .030 bore... Don't go bigger than that you're first time because if you mess something up you can clean up the bore by going to a .040 or .050, .060..... so start with a .030 so later you can fix the bore in case something get jacked...... hope this helps...

litch2004

iTrader: (1)

That helps out alot. Thanks OutlawZ
Good luck with your engine as well

PortPros1

I several LT1 383's going and have built many of them, just ask around about us. If you need heads, cam, machine work etc, I'm in Austin and would be happy to help.
Check out our website at www.PortPros.com

Harold
512-257-0222

OutlawZ

iTrader: (4)

Yeah Harold down at Portpros would be a great source of info for your build. Have a professional sit down with you and explain the pros and cons and prices of each on average... that way you make an informed decision based on your needs.... And harold did a beautiful job on my intake and built Tony Shepherds motor so he can do an LT1 from mild to wild...

draggin97s10

iTrader: (2)

a 396 can also be a 3.75 crank with a 4.100 bore

94Z28rag

iTrader: (10)

It will work, but you'd need a 2-1 RMS conversion kit.

maddog05

LT1'S HAVE THIN Clndr. WALLS and cannot be bored to 4.10" so the math may be right but impossible with a stock block.http://images.ibsrv.net/ibsrv/res/sr....gif:confused:

bigj2717

iTrader: (15)

Yeah for the 383 you run a 3.75" crank 4.030 bore and I run a 6" rod. You can use that head/cam package on the stock short block and it'll make good power

DopdBrd

iTrader: (25)

You can't run a LE3 CAM with stock pistons. The valves will hit and your pistons will hate you. Fitting a LE3 kit on a 350 has nothing to do with the heads or the intake but in fact has to do with the piston/valve clearance with that big of a cam and stock internals.

There have been plenty of people running a LE3 kit on 350's, the thing is, they usually rebuild the motor with forged internals to handle the RPM needed to make power with that kit. When this is done they get the right pistons so your valves aren't kissing the top of your pistons. Also, usually when people do this they will bore it .030 over to get a smooth new mating surface for the new pistons. So when you hear of people doing a 355 to get a LE3 kit to work, it's not because the heads and intake won't work, it's so they can replace the pistons to keep the valves from hitting it.

Catch my drift?

Puck

iTrader: (17)

This thread is from 07.