GM rocker arms

[Wally A.]

case of argument, GM ever produce a stamped steel roller tip rocker arm???

[Duke W.]

Re: GM rocker arms

No. The roller tip rockers used on the nineties LT4 were purchased off-the-shelf from Crane, and I believe they had some durability problems that may have resulted in a recall.

Consider that one time use of roller tip rocker arms an "experiment" that didn't work out.

Duke

[Joe L.]

Re: GM rocker arms

case of argument, GM ever produce a stamped steel roller tip rocker arm???

Wally------

NEVER. EVER. Such a rocker arm was NEVER used by GM in any PRODUCTION application nor was such a rocker arm ever available from GM in SERVICE.

[Mark E.]

Re: GM rocker arms

There's a certain beauty of a simple, one piece design.

I once thought about using roller tipped and/or needle-bearing rockers, but wondered about the risk of those small bits failing then scattering into the engine. Plus I've never had a problem with the simpler design.

[Joe L.]

Re: GM rocker arms

No. The roller tip rockers used on the nineties LT4 were purchased off-the-shelf from Crane, and I believe they had some durability problems that may have resulted in a recall.

Consider that one time use of roller tip rocker arms an "experiment" that didn't work out.

Duke

Yes, there were the LT4 rocker arms. However, these were not stamped steel rockers. They were cast aluminum with roller trunnions. The main advantage of these was the roller trunnion and not the roller tip.

GM did use other roller trunnion rockers in Gen III and IV small block engines. These are investment cast and do not have roller tips.

[Barry H.]

Re: GM rocker arms

Back in 1956 me & a friend pulled the valve covers off his uncles new 55 265 Chevy V8, just to see what a overhead valve engine looked like. After looking it over we were convinced that the "rocker arms" wouldn't last 6 months. (not the last mistake we ever made). Barry

[Joe L.]

Re: GM rocker arms

Back in 1956 me & a friend pulled the valve covers off his uncles new 55 265 Chevy V8, just to see what a overhead valve engine looked like. After looking it over we were convinced that the "rocker arms" wouldn't last 6 months. (not the last mistake we ever made). Barry

Barry------


Yes, they turned out to be a lot more durable than they would seem to be. However, I've never liked them. I think there is too much friction and heat generated. I think the biggest reason for these was cost. They're far cheaper than shaft-mounted rocker arms used pretty widely up to that time.

You'll notice, though, that for the Gen III and later small blocks, GM abandoned this design and went to roller fulcrum rockers. They didn't do that because the earlier style worked just as well.

[Dave H.]

Re: GM rocker arms

Back in 1956 me & a friend pulled the valve covers off his uncles new 55 265 Chevy V8, just to see what a overhead valve engine looked like. After looking it over we were convinced that the "rocker arms" wouldn't last 6 months. (not the last mistake we ever made). Barry

Probably a sound assessment Barry! As I recall, Chevy had problems with failures on the very early 55 small block rockers.