gmcountryboy

Hello everyone, i have a carb'd 6.0L that is currently bolted into a 68 gmc. This year i plan to build the engine up. Im just curious as to how much horsepower i could get off the stock bottom end, i would like somewhere around 500-550 hp. Would that be possible with stock crank, rods, possible higher comp pistons, l92 heads, hot cam of some sort with the edelbrock victor jr intake?? I have also been debating build a 408 w/ l92 heads and a healthy cam. Compression will be somewhere around 11:1. Just curious as to what you guys think would be the best option for bang for buck and horsepower. Thank you!

fast89stang

iTrader: (2)

Mine is a ly6 with l92 heads. 07 6.0. Its stock bottom end, heads milled .020. custom cam, vic jr. Its ran 6.2s @ 2850lbs. That should be around 580 horse depending on calculator. Its way too easy to make 550-600 with these motors.

dogsballs

500+ on stock bottom end very doable, just keep oil pressure up, dont put too much weight or stress thru valvetrain

gmcountryboy

My only issue is im trying to find a cam that works with the l92 heads but still has the agressive lope I'm looking for, I want it to sound like this ms3, and id like to use it, but I don't know if it is a good combo or not, nor do I know much about what these big l92 heads like.

speedtigger

iTrader: (16)

The MS3 Camshaft was designed for cathedral port heads. It has between 13 to 17 degrees of overlap depending on which lobe center angle it is ground one. It would be very difficult to make that cam fit when using square port, large valve heads without flycutting valve reliefs into the pistons. Even then you will likely be disappointed with the peformance of that cam in a carbureted engine. Especially if it is equipped with a single plane manifold.

If you are going to a forged pistons with valve reliefs or you intend to flycut the stock pistons for valve reliefs then you can get the amount of overlap that you want for the sound you are looking for.

This cam has 16 degrees of overlap which would be similar to an MS3 on a narrow lobe center. Let me know if this is the type of idle you are looking for:

Doug G

Bite the bullet and shaved the heads to get some compression, and while the heads are off, fly-cut the pistons which you'll need to do anyway with those big valves and any decent cam.

Just sayin'