hey guys. well im currently undergoing a rebuild on the 91 GTA got the block out. acquired a set of 906 vortec and a sdpc intake im porting along with a set of slp's. decided to go with a comp xr275 cam and a 3000 stall. with that being said heres my question. I ordered a set of screw in studs from summit today. I already have the springs and retainers that clear me to .550 lift new stem seals, hardened pushrods, and valves all from Alexs Parts. I also have a set of 1.6 pro magnum rockers im throwing on.

1.)why was I told that with the screw in studs I need guide plates? The pro mag's are self aligning.
2.)do the pushrod slots need to be elongated?
3.) should I go with shims? like a .015, .030, or .060?
4.)I planed on having them tanked ($50) and assembled by myself. should I take it to the local shop and have them rebuild them? the basic valve job/rebuild runs $198 plus the $150 install of the studs
5.) Is there anything else I should have done to them to clear that cam or am I in the clear?
6.) with that cam do I need the retro fit lifters or can I go with a set of oe lifters such as these?
http://www.ebay.com/itm/SBC-CHEVY-DE...ht_3947wt_1271


any info is appreciated!

 

Lifter style required depends whether you have a factory OE roller block or non roller block;not the cam lift

 

For the valve springs?
Spring setup needs to be measured and the correct thickness shims used to achieve the required specs for spring height

 

I would do hot tank, magnaflux, valve job, screw in studs, and have them check the springs to see if shims are needed. Do it right the first time, if you dont have the tools to get the springs set up, pay them to do it.

 

-You don't need guide plates with self aligning rockers'
-You do not have pushrod slots, that is why you would need guide plates if you did not have self aligning rockers.
-You need to check the spring installed height to determine if you need shims. The studs need to be installed correctly, unless you can make sure you are doing it correcly have the shop install the studs.
-As mentioned you do not need retro fit lifters, use stock style lifters.

 

1.) It depends on the studs you get. Most screw in studs are meant for guide plates, you can use those studs if you run a washer to compensate for the height of the plate. I had serious issues finding a screw in stud that worked with self-aligning rockers on vortec heads. The bottom of the rocker was hitting the nut on the studs and seating about .3" too high. I ended up running the cheap Mr. Gasket studs because they just have a collar (like a carb stud that needs to be double-nutted to be put in) as opposed to a bolt with an attached nut.
2.) Push rod slots do not get elongated with self aligning rockers, only NSA.
3.) You'll have to assemble the heads and than shim accordingly. Very rarely will you get away without running shims and their is no telling what size you will need before hand.
4.) I'd let the shop do it if you've never done it before. My heads ended up costing me $600 in labor (tanked, valve job, remove studs/drill & tap + install, disassemble/reassemble check seat heights).
5.) Everything I needed for my vortecs was as follows:
springs -26918-16
retainers -787-16
locks - 648-16
studs - 1076
shims (forget the part number)

Honestly I could have bought a set of aftermarket heads for what I invested into my heads. Whatever though

 

thanks for the info guys.I appreciate it. I more than likely will be taking them to the shop to have it done...$325 for the valve job, tank, machining the guides, and a rebuild. accompanied with the alexs parts springs, valves, seals, shim kits, and pro mag rockers. guess I could have gone aftermarket heads :/ hopefully she gets the job done though!