Higher ratio rockers

[rpounds]

Has anyone had any experience with 1.6 or 1.65 ratio rocker arms on L-48 350s? If so, give me the scoop - good, bad, indifferent. Horsepower gains? Torque gains? Stock valve covers or tall? Stock valve springs? What brand did you use? Any other information that would be pertinent.

Thanks,

Ron

 

[Bullitt]

Roller rockers

I've used a couple of ones from different manufaturers. It helps your cam see a bit more lift than normal. The advantage really comes from the reduced friction they provide, causing less wear and tear on the engine. I really haven't seen the big horsepower claims on a street engine, like the 15-30 that is advertised. It's probably good for a handful, though. Most aluminum rockers are going to need taller valve covers. Comp Cams makes a Magnum steel roller-tip rocker similar to stock that should fit with no problems. I'm not sure of the maximum spring load on a L-48, but unless you are swapping a cam, I would think that you're pretty safe. Unless the engine is going to be a big bruiser, I'd stay under $200 for these and concentrate on something else.--Bullitt

 

[Joeverb]

The biggest difference they will make is a smooth rev and longevity. Any significant power increase normally comes from the inaccuracy of the existing rockers on the engine, if they are originalthen they are likely well worn and you should feel a bit of difference just because the rollers are accurate.

 

[69MyWay]

I have installed both the plain stamped steel 1.6 ratio (long slot) stock style and full needle bearing roller rockers. You can get the plain stock replacement stamped steel for about $50. The plain stamped steel do not require any modifications at all (kind of boring huh?). They are a good replacement on a full stock engine when doing a rebuild.

The rollers all depend on the brand and style. There are several out there that will fit under a stock valve cover by using the rubber/steel insert valve cover gasket (did it on my V8 Fiero).

Will you feel a difference?--No. You would have to Dyno the difference. However, the roller style give the engine the ability to rev easier and with less friction.

I try to run full rollers on every engine I build for performance. I only run 1.6 if the cam manufacture recommends that addition. Otherwise, I stick with the 1.5 ratio and get my lift from the cam.