I am building a 6.0 for my wife's Yukon XL. It will be an 11.1 6.0 with a 218/224 114 cam with lift in the .560ish range intake and .580ish on the exhaust and Dart 225 Pro 1 heads. Before the motor goes in I am thinking about putting on some roller rockers, if I deside to go with them is there any reason to not run 1.8s or should I stay 1.7? The springs on the heads are good for .630 lift, I am just looking to free up some HP, also what would be the best balancer to put on that would have a slight UD to again.....free up some extra HP? I am looking for good parts that aren't the most expensive parts. The goal is 400+ whp so I am just trying to get there.

 

Jegs has the Proform rockers which are a billet aluminum roller rocker the 1.7s are 221.99 and the 1.8s are 209.99. I want to see how the 1.8s would affect the camshaft lift and performance of the motor.

 

Save your money

 

Well I was told at one time that once the lift gets over .550 the tip of the rocker digs across the tip of the valves. Supposedly the stock rockers weren't designed for lift numbers over .550 and the geometery of the rocker at the valve isn't best suited for such high lift, so that is why I was kicking around the idea of roller rockers. The UD crank pulley simply because the stocker ways a metric ton. So I was thinking maybe the addition of the UD ratio as well as the lighter weight would help the motor turn up faster and save weight. Much like the theory about taking off the engine driven fan in favor of electric fans and electric water pumps. Gets weight off the from of the motor and reduces inertia of the motor from idle to redline I think. I could be way WAY off but I am just kicking around some ideas.

 

I would recommend the Harland Sharps at stock ratio. Most other adjustable rockers require spacers or extensive valve cover reworking for clearance. You could run the stock rockers with that cam no problem.

 

I checked the wipe pattern across the tip of the valve with my new cam (.612 lift) and it's fine. Don't believe everything you read. Also the heavier balancer will dampen and absorb harmful crankshaft harmonics better than an aftermarket unit will as well. It's your call.......

 

I guess I will see what my money looks like when it comes time to start ordering the top end parts.

 

I think I am going to pass on the balancer, but I am still thinking about the Comp Pro Magnums, and the Yella Terra rockers

 

roller tip rockers weigh more than stockers out toward the tip... not a good thing for a valvetrain. Personally I think one of the only reasons they are around is because of their popularity in the SBC days, and they do look sweet. I look at it like this, there are cammed 600+ rwhp 7500rpm LS7's running the stock style with no problems, I think they'll handle a sub 6500 rpm truck motor.

Now having the stockers modded by harland sharp is a great idea to help durability.

 

I have ran the comp pro mag's on a few different motors with mixed results...SBC's seem to respond well to them while the newer LS motors, it didnt seem to help nor hurt performance...I would say run the stocker's on the LS engines.