Some people have claimed up to 200 HP for a 3.4 replacement for the 2.8, but I am very sceptical. The GM performance 3.4 is rated at 160 hp. A 25% increase through intake mods and a mild, mid-range cam is beyond my imagination.

I would guess that a very fresh GM performance 3.4 with Holley or 4.3 TBI, even with roller rockers MIGHT get to 175-180 horse, but that is a huge increase over the stock 2.8 at 130.


Jim Paget
88 YJ with a few changes

www.rrr4x4.com