RAS3 only Pontiac 421 GTO 389 Screw in Rocker Arm Studs set of 16

$119.00

Description

set of 8 – half set (see my other listing for set of 16)
RAS3 (studs only) from Spotts Performance
Requires 7/16 poly locks – see my other auction for both studs and poly locks
US MADE SCREW IN Studs – set of 16
These replace Press In Studs on 389 and 421 heads.
Very Popular for 64-66 GTO’s and Big car 421’s
High quality studs are 1/2″ course thread at base and stronger then factory 7/16 threads at top.
Heads will need machine shop to pull studs and tap to 1/2″ thread
It is not recommended to hand tap your heads !!! Your studs may not be perfectly straight when installed.
In the past, I’ve had to tap and heli coil for a 7/16 base thread, machine stud boss and then cut down the base of the screw in stud. to allow rocker arms to fit under stock valve covers.
This kit is a time and money saver!!!
Studs do not have oil thru holes on certain pre 64 heads,
simply use rocker arms with oil hole (see may other auctions)
On oil thru stud applications, I also plug the block with 2- 1/8 npt pipe plugs at deck to keep oil away from heads.
This set up will allow factory valve covers to fit!
These studs are for all stamped steel rocker arms (factory with oil thru hole)
and also roller tip rocker arms.
Some aluminum and stainless steel rocker arms will work as well.
See my other Pontiac engine parts listings