just wondering what the biggest stroker for an ls1 5.7lt block is? stroke only without sleeving the bore. i have to use the 5.7lt block

 

ERL has a 4.500 stroke on their 500 inch ls2, but that required a deck plate which meant sleeving the block. 4.125, from what I hear, is the biggest you can run. After that theres too much side loading on the pistons, which is a bad thing.

 

i think it's a 396... stock bore, w/ a 4.125" stroke.

 

The ERL tall deck LS2 uses a bore from 4.125" to 4.200", stroke in either 4.250" or 4.500", and a rod length from 6.600" to 6.800". It has a 10.200" deck height, so it's like a tall deck big block in an aluminum small block package. The smaller bore is recomended for forced induction or nitrous. I don't have a way to post the literature.

 

Lunati does make a 4.25" stroke crank for LS1's.

 

4.250" would be too much for a motor with 6.000' or even 6.125'" rods because the angle that rod is at at 90 and 270 degrees of crank rotation would push the piston against the cylinder walls too hard causing increased wear and IMO increased friction which will rob you of power.

Quick Carl,
According to the spec sheet I got from ERL at the PRI Show, they're actually using bore sizes of 4.155 to 4.205.

 

454ci is the largest I've seen on a 5.7L block. Thats a 4.125" bore sleeved block and 4.25" stroke crank. It would take a lot of machine work to allow the crank the clear the block.

 

Thanks , your right. It's 4.155 to 4.205" bore. I believe the motor for Chuck was going to be 4.125", so you must be able to request the smaller bore.

 

I am building a 455 ci ls1, but thats includes resleeving the block. I am using a lunati 4.125 stroke with a 4.190 bore.
Jon