Hi Everyone,

I am swapping an LT1 from a '96 Caprice (the one with the iron heads) into a '90 firebird. Can you guys answer a few questions for me?

1. Did the '96 Caprice LT1's come with hardened pushrods?
2. Did the '96 Caprice LT1's use guideplates and NSA rocker arms?
3. If I am dropping a CC306 in this engine, do I need to replace the stock lifters (they have 28K miles on them)?
4. Again, with the cc306 and if I get 1.6 rockers, will I need to replace the stock pushrods (also 28K miles on them)?

P.S.: I will be replacing the valve springs and associated spring hardware with the cam.

Thanks!
-Andrew

 

No the pushrods are not hardened, to run guide plates and non-SA rockers you will have to pull the heads and put in screwin studs and machine for the plates which is good since you will need to pull the heads and machine the valveguide if you want to run that much lift. If you do not want to pull them you have to run SA 1,5s with that cam and then frankly you will be pushing the pressed studs closer to their limit than most people would care to. If you do machine for the other stuff I still don't see the point in that much lift, have you looked into the flow for those heads all the extra lift will do is stress components unless the heads are ported and flow well at high lifts.

 

Do the iron heads not come with screw in studs like the aluminum LT1 heads do? I admit I don't know much about the iron heads, but thought they were just like the aluminum ones-only iron. If that is the case, there would not be any machining needed for any of that.

 

I assumed they would have screw in studs as well, but 96capricemgr says no....hmmmm.

I will pull off the valve covers and have a look when I get home.

 

No the irons come with pressed, it is possible to pull the studs at home and tap with a $15 dollar tool plus a tap but the heads have to come off because the studs protrude into intake ports, also the spring pockets are smaller and stock even with the right seals and retainers you need to measure to try to go beyond say .550 or just machine the guides first to be safe. On the guideplates I don't know what works best for the aluminums but the irons the GM ones fit best guys have had troubles with some of the aftermarket stuff binding and chewing up even hardened pushrods.

 

AFAIC, Dwayne knows what he is 'talking' about.

 

Ya ive had 2 96 Caprice.impala SS motors, they are PRESS IN not screw in for sure. Go to www.impalassforum.com and talk to the guys there they know those heads inside and out backwards and forwards.

 

the 94-96 Caprice had the L99 265 CID motors not the LT1 didnt they?

Maybe it was just some of them.

FYI- the iron head rocker studs are a press in.

 

Forgive me, for putting words in your mouth.