Long time plans for the car are to build a forged 383, supercharged. So that said, I dont want to buy RR's now, then 2 years from now have to buy other ones.

Also should I be getting Self Aligning or Non-Self Aligning? Whats the differences?

The ones I was considering are ...

1) Comp Cam Pro Magnums, 1.6, 3/8" stud

2) Crane Cams Gold Race Extruded billet aluminum, 1.6, 3/8" stud, SA or NSA ???

3) I was jsut wondering about these ... Harlard Sharp Aluminunm Roller Rockers, 1.6, 3/8" stud.


I DO NOT want to buy RR's and have to get different ones when I finally have the $$$ to do a forged & boosted 383. Its going to cost enough money beefing up the rest of the car too have to make the same purchase twice

Im really leaning towards the Pro Mags rite now, but I heard the Crane ones are pretty good too. Actually, isnt that what comes from the factory in a LT4 ??? How do these compare to the Pro Mags? And are there any better suggestions besides the Pro Mags ???

 

I suggest the Comp Promag NSA 7/16" rockers with ARP 7/16" studs. Make sure you use the GMPP guideplates, p/n 14011051 qty: 8. Standard SBC guideplates will not line up correctly, as the LT1 has a 0.050" difference in the valve spacing.

 

There is no reason to stay with a 3/8" stud. Aluminum rockers, like the Crane's are nice but probably don't have the longevity of a rocker like the Pro-Mag if you are running very high miles or stiff valve springs. For a hyddraulic roller, they would be my first choice due to the weight. They will last plenty long enough on a supercharged motor, as something else is sure to break first! For very stiff springs (like those often used on an SR cam) the Pro-Mags.

In general, I agree with using guide plates rather than SA rockers. Better high rpm valve train stability. However, if it's a low rpm (,~6,500rm) motor you could stay with SA and avoid the cost (minimal) of the guide plates.

Rich

 

Ok thanks guys ... Im still not too sure about what kind of RPM's ill plan on spinning it too. That all depends on how my final set up in a few years comes out. But it wont be seeing anything that high now.

Is the GMMP guideplate strong enough to support them at high rpm on a high strung (Boosted 383) engine? If not ( However, id imagine it is cause LT4's rev prety damn high and GM uses that on them ) are there any aftermarket ones I should be looing at instead that are stronger/more reliable? Cost isnt a HUGE issue. I want to do the job rite, the first time.

RSKRAUSE ~ Your car is awesome. PM me sometime if you dont mind, Id like to hear a little more about the specifics of your setup. Nothing too detailed, inless you want to speak up . Seems like hardly anyone is running a boosted 383, and alot of people throw out bad information/advice since its a fairly uncommon set up.

 

Guideplates aren't under a lot of stress, so don't worry about that. My comment about perhaps not using them was really just informational/for completeness. I would recommend using them along with a NSA rocker. Just to reiterate, I like the Crane rockers for most hyraulic setups. When you get into very high spring rates, as usually used in a SR setup, the the stronger Pro-Mags (or equivalent) are in order.

Thanks for the nice comments! There's a lot of boosted 383's, and a lot of blown 383's, but I think I was one of the first to do both boosted AND blown. The idea, which has worked out well, was to have a very streetable blower setup and use the N2O at the track, when there is more traction available and race fuel can be used. With a heavy car like mine (~4,000lbs) that extra low end torque from even a small nitrous shot (75-100hp typically) really wakes it up off the line. Then the blower kicks in. Fun stuff.

Rich

 

What he said. Nuff' said.

 

My feelings on the subject as well. Don't stick with the 3/8ths since youre buying go ahead and spend 30$ additional and get 7/16ths studs and guideplates.

Pro mags all the way. I have had the other stuff break around the pro mags and they came away only scuffed whereas Ive had the same failure with alum rockers and they almost disentigrated.

 

Not to mention that the Pro Mag bodies are warrantied for life. Due to error mostly on my part, I had the SA tabs get ground off of six rockers, and Comp warrantied them. They rebuilt all six with new bodies and roller tips and re-used the bearings and trunions.

 

I would also like to add a question. Now would it be possible to run a 1.7 roller rocker like the scorpions on the set-up he is describing? This would allow him to run a less agressive cam and still good lift numbers.....or would that be pointless to do? I have been asking myself the same question. I need rockers and was thinking either 1.6 mags or the 1.7 scorpions. I have heard the 1.7's offer better gains on stock motors, but am wondering how much there effectiveness wears off as you get to a blown 383?

 

Actually it would be nice for a blown car because you could keep the duration down and still have the lift.

 

Couldnt 1.7's lead to piston-to-valve clearance problems though on a blown stroker with a custum ground blower cam? Thats the only reason I haven't considered 1.7's ... Thought it would limit my possibilites some later on down the road when im on the market for a custum grind for my blown & stroked car.

Cause with some of the bigger cams, I thought 1.7's may have it too close to the piston. Although I am not very knowledgable about cam design.

I've heard alot of good thigns about the 1.7 Scorpions, but wasnt sure how they were durability wise compared to Comp Pro Mags ... Anyone want to point in the rite direction and awnser some ?'s again lol ? I wont be ordering them for a few weeks still, but when I do, I want to be sure that I made the best decision to get the best power & reliability out of my setup, both now, and in the future.

 

I guess it would be smart to put new valve springs in if I went to 1.6 or 1.7's too wouldnt it ... ? The kinda screws me though cause then ill have to buy new ones in a few years when I finally get the $$$ for a GOOD 383 with a blower, custom cam and nice hogged out heads

 

I was thinking CMS 611 valve springs or GMMP LT4 Hot cam springs like 40$ ...

Also just wondering but shouldnt they give me close to if not slightly more then 10RWHP? Id rather estimate conservatively than to overestimate here ... Some say 15, but that sounds pretty high for a stock cammed /headed car

 

O yea one more thing ... Wouldnt 1.7's through the valvetrain geometry off? And put unneeded stress on it? I thought that was why ALOT of serious drag cars only used 1.5 RR's . Less strain, and then made up for that with low ratio with the custom ground cams ... Im jsut going to go with the Pro Mags 7/16ths ... But ... Still need to know what springs I should get ...

I dont think I could run my car with the right springs now for what ill need on a custum cam when I blow/stroke this this thing ... Like they'll be too stiff, and may HURT performance. I guess ill just have to do springs twice huh ?


Wow that sounded wrong, when I blow and stroke this thing

 

That's why I went with the 1.5 Crane Gold RR's and a custom ground Cam