I need to return the set of rockers I purchased from summit, and I need to find a differant set. These are going onto an LT1, fully roller, 1.5 ratio, 3/8 stud, and NSA. what are some of your preferences? I'm looking at Scorpion and Harland Sharp aluminums right now.

 

Have you looked at the Comp Ultra Pro Magnums?

 

aluminum is no good for a daily driver

 

i have used the comp pro magnums, (non-ultras) with good results.

 

then I ought to look at the steel roller rockers. It looks like 1601-16 is the part I need to get then. thank you for the advise guys, I appreciate it.

 

I think you'll like them.

 

Any particular reasons you say this?

M

 

material fatigue vs a steel rocker makes it less reliable. doesn't mean it won't work, just not as reliable. i have a set of crane blue racer aluminum roller rockers in a street motor with over 80k miles on them so far, but with the availability of rockers like the comp pro-magnum line, that are 15% lighter at the valve than aluminum rockers, and are far more reliable, why wouldn't you want to use them?

 

aluminum can fatigue and crack and sometimes the rocker body falls in sideways and can hang the opposite valve up and take out a motor.

 

I understand the material fatigue issue but I would go with the feeling that it is only a real issue with a high lift, high spring force, higher rev motor built for serious performance. My build is going to be a non-track DD. The only issue I see is possibly high mileage therefore high-cycle fatigue. I wanted Comp Pro-Magnums because they are steel but I need 1.7 ratio rockers 'cause I am going with an LS2. The aluminum Ultra Golds from what I have researched are all Comp can provide me with.

M

 

if you're going with an lsx engine with DD in mind and you want reliability, go with a comp trunion upgrade on the stock rockers and be done with it. i have a moderate camshaft, and the engine sees 7000rpm shift points, running upgraded stock rockers with no issues. the benefit of an aftermarket rocker on an lsx engine isn't realized till you need an adjustable valvetrain like what would be associated with a solid roller camshaft.

 

The main feature of roller rockers I want for the engine is the roller tip. I want to minimize if not eliminate the side load on the valve stem as the rocker swings through its arc opening & closing the valves. Current 350 in my car has the roller tip only Comp Magnums. Last year at ~60k miles I checked stem play on a couple of valves and it was in the bottom end of the range of allowable tolerance on each. I like to take the mileage on my engines well into several 100K before having to rebuild or replace. My theory whether valid or not is that less stem slop helps for longer valve seat geometry life and therefore better sealing for longer.

M

 

so original post is talking about an lt1, now you're talking about an ls2 motor....which is it? And I've seen several ls based motors into the 250k+ range still running stock rockers, which are the best choice for a daily driver, no reason to upgrade like older gen 1 motors.

 

I know a 412 7500 RPM Paxton charged street driving raced regularly LSx that used stock rockers, didn't even have the trunion upgrade (forget the lift, but that guy doesn't do anything small).

Okay, let's keep the posts on-topic to the original LT1 question. The ones wanting to discuss LSx will have to go get a room...