Ls2 with ls3 top end.
Race Director
Joined: Aug 2005
Posts: 13,592
Likes: 187
From: Hudson WI
NCM Sinkhole Donor
Use LS2 rocker arm bolts, and they don't work on LS3 heads. One of the bolts broke, sounded like a rod knock because the push rod was bouncing around, so I used as an excuse to build a 416" LS3 short block to go with the top end.
Former Vendor
Joined: Aug 2005
Posts: 16,897
Likes: 412
From: Lewisville TX
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
It was a super popular setup in late 06 and 07 because the LS3 hadn't come out yet and everyone was doing the L76 setup (same thing). You do loose a little bit of torque down low vs the LS2 but it gains a lot more up top from the better intake and head flow. If you change nothing else (most do a cam at the same time) you should put down stock LS3 numbers.
Racer
Joined: Mar 2005
Posts: 262
Likes: 3
From: Tempe AZ
lS2/LS3
I did that when I had my C5. Be careful of cam selection unless you are going to fly-cut the Pistons. I didn't fly-cut. Had no issues. I milled the heads too to bump the compression.
Last edited by JonLT4CE; Jun 17, 2016 at 09:47 PM.
