If I'm not doing a head/cam swap for a while, would it be worthwhile to step up to this high a ratio rocker with the appropriate valve springs? Who makes this high ratio rocker with matching springs? Would I also need new valve covers? Thx.

Planning on doing this at the same time of a header install + tune.

 

I think the brand is scorpion that makes alluminum 1.7's. If you still have the stock cam it'll raise the lift from .447 to .506, and new springs and stuff would be a good idea at that time. and you'll most likely need tall center bolt valve covers instead of the stock ones. I've also heard of the LT4 valve covers working.

 

How come the most common type of roller rocker seems to be the 1.6? Why don't people use the 1.7 on larger cams? And how come I see people sometimes with 1.52's with a .600 lift cam?

 

I'm assuming less flex at higher RPMs with the lower ratio rockers. Think its better to have the lift ground into the cam. But in my case where I have the stock cam, I'm not going to sweat it till the next rebuild.
So LT4 springs are enough?

 

The LT4 springs can handle about .520 lift or something max. so if you're going with just 1.7's and no cam, they should do the job.

Kurt Crosbie: i think most people go with 1.6's because it's not over the top, but also adds some lift. 1.7's are more for people that aren't going to do a cam swap or are racing. i don't know why people go to 1.52's from 1.5, i think it's a waste personally, you gain about .005 lift. It brings it from .447 to .452

 

Perhaps people use 1.52 because it is a common aftermarket part. I don't think anyone would want to use stock rockers on a 12:1 setup with 250/256 cam.