99 k1500 suburban 5.7 vortec upgrades

[Supercharged111]

It's not a significant gain, but I added them to my marine cam anyway.

Dyno Testing New Mods for the LT1 Motor - Part 2

Welcome back to our project LT motor build. As you'll recall in the April 2013 issue of GM High-Tech, we tested a bunch of simple mods for the admired LT motor

www.google.com

 

[Erik the Awful]

If the rockers would be an easy 7-10% when tuned, what are the recommended rockers to run?

Note that in the article Supercharged111 posted, they gained 8-ish hp, which is not 7-10%. The peak hp gain was barely over 2%. I won't say that's not worth it, but you have to judge it against your budget. Here are the appropriate long-slot, self-aligning 1.6:1 rockers.

Elgin Stamped Steel Rocker Arms 1.6 long slot; Late model; self-aligning

KMJ Performance

www.kmjperformance.com

Standard rockers with roller tips are just a gimmick. Full roller rockers are only worth the money if you're going to be running in the 5000-7000 rpm range regularly. Some people like the idea of rollers for reduced wear, but the factory rockers don't have a problem with wear. I'd keep those extra dollars for parts that give measurable benefits.

 

[Superchargeme]

Can they be added to a stock engine without opening up the pushrod holes? I had seen people say both ways.

 

[Supercharged111]

Can they be added to a stock engine without opening up the pushrod holes? I had seen people say both ways.

I had to punch mine out, but @L31MaxExpress has gotten away without it. I smothered a pushrod in magic marker, installed, rolled the motor over a few times, and had a bare spot on the pushrod. This was with a stock cam and Comp Pro Magnum chromoly 1.6:1 roller rockers. Once the heads came off I said F it and threw in a new takeout marine cam since I was in there.