Thats a good question . I don't know for sure. The LS1 rockers are roller tip however and I am sure that was mandatory because of the "arc" motion I mentioned. I don't know the exact answer but GM has different standards when they are building production motors. They will give up 5 HP if it save $1.00 on each car they build. Also, maybe this setup is slightly quieter which is very important in production engines. Maybe someone else can give the exact answer. The millions of dollars that GM spends on engineering is hard to argue with but you have to remember that their goals are probably different from yours.

I don't think that high ratio rockers are all bad, but my research led me to believe that it is best to just have the lift built into the cam. I am always up for learning something new if anyone else has a good point to make.

 

Don't quote me on this, but I believe that since the crank sits higher in the block of an LS1, GM used a smaller radius for the cam for clearance. The larger ratio shaft mounted rockers make up for the small lobes on the cam.

 

The journals are bigger in the LSx motors then they are in a sbc there for the lobes are larger. Also, cam location and lifter angel have a lot to do with the arc of the rocker. I think that the cam is higher in the block then in the sbc also, I am pretty sure that the rockers on the LSx motors are stamped peices and they are not shaft rockers, but might as well be. They aftermarket ones are atleast $450!

 

The LSX rockers are still shaft mounted whether they are stamped or not. Oh, and $450 is a deal compared to shaft mounted rockers for our engines.

 

I have to disagree with you on this one. The stock peices are stud mounted stock, now aftermarket is a different story. Also that price is for stud mounted, not shaft.

 

I talked to brent last week, I haven't had time to post. After talking to him for about 1/2 hour this is what we decided on

230/236 cam 112 or 114 LSA, haven't decided that yet

24lb SVO injectors
255lb walboro pump
52mm TB
1.6 RR
Cutout
3600 stall

he said that setup on ET streets should run 11's. Power peak should be 6200-6400. He said a tune from PCMforless would be alot cheaper than his dyno tune and be within 10-15hp.

I think Flyboy is going to order the heads/cam beginning of next week.

If anyone has comp R lifters, 1.6 RR's or a 52mm TB for sale let one of us know.
Thanks

 

Well I got the heads this weekend. They look really good. The cam/lifters should be here tomorrow. As soon as I finish cleaning my garage up I am going to start on the car, I wait until its freakin 8 degree's. The only parts I don't have so far is the throttle body, but what I have read about the aftermarket pieces I might just have the stock one ported(isn't there someone on the board that does this?) It's going to be an experience dropping the engine out the bottom, especially in a one car garage, space is going to be at a premium

After I get Flyboy's 93Z done, another friend of mine with a 94 T/A wants the same thing done, thanfully I am not rebuilding the short block in that one.