I want to get new rockers for my car for some security and to see if I can get more power out of my set-up. I want to know which you guys would prefer. I'm kinda liking the comp ones with the guide plates and everything. Just want to see which would be more benificial.

 

IMO, you are comparing apples to oranges. One is adjustable and one is not. I had the Yella Terra's. I am going with CC Pro Mags for adjustability.

 

I thought that the yella terra's were adjustable. Thanks for your input.

 

Are these the same as the J2Ks?? I get confused looking at their website Adj Rocker info.
joel

 

I think J2K are Jessels. Not sure though. If they are then they are shaft mounted and if they are adjustable then they need valve cover spacers. The Comp Cam Pro Magnums are adjustable. They are not shaft mounted, they are stud mounted and they have the needle bearings like the stock ones.

Supposedly on the driver side baffle in the valve cover needs some grinding for rocker clearance of the CC Pro Magnums. Since I have the LS6 PCV mod I my driver side valve cover is sealed and I don't need the baffle anyway.

 

Come on guys. What is more benefical the shaft mounted or the guide plates?

 

If you just compare shaft to guide plate only then the shaft is better.

 

I was advised that the comps 7.5 ratio was an issue with a larger cam.

 

Don't forget that with the CC Pro Mags you also have the added expense of hardened pushrods which are required when using guide plates because the stock pushrods can't handle the gauling the guide plates cause on the sides of the pushrods. That having been said the CC Pro Mags are very high quality and are adjustable and don't require rocker cover spacers even if you do have to pay extra for a set of hardened pushrods.

 

I already have hardened pushrods. I want to know more about the 7:5 having problems with the high lift cams..

 

Anything over .550 lift and you can forget all ratios except stock 1.70

 

If you change cam lift or rocker ration you need to check PtV clearance via valve drop method or the heads off clay method. There is a way to check the lift effect of rocker ratio changes but I don't have the equation in front of me. If I come across it I will post it.

 

Seems to me that you can always have problems. If you don't run into coil bind and you have enough piston to valve clearance, the extra lift from the 1.75:1 rockers won't hurt. I have them with a 232 degree .595 lift cam. I made sure the springs would handle it and may have to notch the pistons. If I had gone with a 228, the only worry would have been the springs.

 

Neither - I'd go with the Harland Sharp (I did)

 

Why?? What are Harlands advantages??

 

Crane has a fully adjustable 1.7 rocker like their 1.8 that fits with no alteration of the covers and comes with hardened pushrods and guide plates. They are also sold under the VHP name and are at that site for 639 or so for the kit. They weigh less than the over weight YT's and are FULLY adjustable.
Good luck

 

That couldn't be farther from the truth. .550 lift only jumps to .566 with 1.75 rockers. They are really only a issue with high lift cams. Then you just have to make sure you have enough clearence and your springs can handle it.

 

Harland Sharp rockers...
price, direct bolt on, no worrying about adjusting

 

Beast 96 how do you come up with the more lift?? do you have the formula on find out how much lift it would be?? thanks

 

divide the cam lift by 1.7 and then mutiply by the new rocker ratio:

550/1.7=.324 .324x1.75=.566