How much small horsepower and torque would be added to a lg4 engine? Probally not enough to warrant the expense.

 

I think you'd be suprised.

 

Any one else care to estimate. I don't really understand the formula, lobe lift x 1.6. The lg4 cam specs is 178-194 0.350-0.385-109 seperation. I think by research 4 degree increase in camshaft duration with 1.6 rockers.

 

The lift is what you say. Divide the lift by 1.5, then multiply by 1.6 to get the new lift.

As for the duration, the duration ITSELF doesn;t change but the .050" will see an increase of about 3-4 degrees. Depending on what rockers you go with, it is worth it. I put the Comp Magnums on my LG4 that i have. I'm not going to say whether or not I feel a difference, but it's a cheap way to get a bit more lift and a inkling more duration (@.050") without actually changing the cam.

I would say go for it. Remember, they are a crossover part, meaning that they are not specific to either the 305 or 350. SO if you swap heads or anything, you can swap the rocker arms over.

 

.373/.410 lift with 1.6 rockers

 

roughly 13rwhp.

 

more if you go full roller

 

I switched to a set of 1.5 rollers rockers and there was a noticable increase in power and throttle response.
After all the major mods have been done, like headers, cam, and a good set of heads. Then it's good to begin working on mods like roller rockers that don't nessecarily offer as great a HP/$ increase, but they do help out none the less.
Roller rockers get the from me

 

From just upgrading to 1.6 rockers, wow. Looks like I may have a new mod to do Chad did you do the upgrade yet?

 

Yep, Stock LT1 guys have gained around 13 rwhp. This was dyno proven.

 

Can you still use standard pushrods with the 1.6's or do you need shorter/longer ones?

 

And do you have to slot the pushrod holes in the heads using 1.6?

 

You can use the same pushrods, and most of the time you will not have to do anything to the heads.

 

But check to make sure, I have installed 1.6 rockers on my L69 and I'm going to have to open up the guideslots in the head.

 

The increase in power isn't so much from the ratio increase of .1, its because a set like those will be alot stronger than the GM ones, so they won't bend like the GM ones. GM says theirs are 1.5 ratio, but because of the amount of flex in them, its usually alot lower, like 1.2 or so. Sometimes even less, depending on the cam.

 

I don't know, depending on the valve springs you're probably right, but If your running fairly mild springs I don't think it'll be a problem.

 

You'd be surprised.