[dirtinla]

Intake valves 10241743
Exhaust valves 12550909
Springs 10212811
Retainers (cap) 10241744
they are the exact replacement springs and valves that come in the 602 crate motor which has vortec heads.

This is the question that has been raised:
Im no expert but, It is my understanding that the vortec valves which he has bought has the groove for the locks (keepers) further down the stem. and will not work in an earlier style head anyways, because the valve will not open enough for even a stock cam. I may be wrong on this, so someone correct me if I am.

Thanx in advance
-=Fred=-

[C-10]

Un-altered 882's are 1.94, 1.5 valves. That is what your valves are. To my understanding GM moved the locks and retainers of vortecs down slightly for use with self-aligning rockers.

The issue would be coil bind. Set a cylinder of a head up on the bench and do some measuring.

[F-BIRD'88]

Keep the valves and ditch the 882 heads.

[dirtinla]

This is a racing class where 882's are a requirement of the class. So that's not an option.

Thanx'

[oldbogie]

Originally Posted by dirtinla

Intake valves 10241743
Exhaust valves 12550909
Springs 10212811
Retainers (cap) 10241744
they are the exact replacement springs and valves that come in the 602 crate motor which has vortec heads.

This is the question that has been raised:
Im no expert but, It is my understanding that the vortec valves which he has bought has the groove for the locks (keepers) further down the stem. and will not work in an earlier style head anyways, because the valve will not open enough for even a stock cam. I may be wrong on this, so someone correct me if I am.

Thanx in advance
-=Fred=-

The Vortec valves are taller overall, and in relation to the stem tip, the lock is lower but in terms compared to non Vortec valves the spring height will be the same. The additional stem length above the lock is to provide space for the alignment bosses of the self guided rocker. The big issue when using these valves in heads that are not common to the self aligning rocker is that the pushrod needs to be lengthened to obtain proper sweep on the stem tip. There is no effect to how much the cam will open the valve. The issue will be getting the geometry correct between the rocker and valve stem tip. It not a show stopper issue if your running less than .45 inch lift. It the geometry will add a little side thrust to the valve stem but it'll work. Getting over .45 inch lift the offset loads on the stem will greatly accelerate wear on the stem and guide. It's always a good idea to set the geometry to minimize these off center loads on the stem, but over .45 inch lift it becomes imperative to correct the geometry. The situation has an additional risk when using a roller tipped rocker as one could create a situation where the roller comes off the stem tip, which will be a messy situation.

You can run early valves in a Vortec head if you're not using self guided rockers or if you do put lash caps on the stem, although these frequently interfere with side to side clearance on the rocker guides.

Bogie

[machine shop tom]

Bull Poop!

Has anybody even bothered to actually do any measuring?

The Vor-Tec and non Vor-Tec valves are practically identical (within a few thousandths).

I just measured some used valves and also checked my SBI catalog.

The same. No differences between them in dimensions, keeper-to-tip distance or anywhere else.

tom

[oldbogie]

Originally Posted by machine shop tom

Bull Poop!

Has anybody even bothered to actually do any measuring?

The Vor-Tec and non Vor-Tec valves are practically identical (within a few thousandths).

I just measured some used valves and also checked my SBI catalog.

The same. No differences between them in dimensions, keeper-to-tip distance or anywhere else.

tom

About .040 if you bother to measure.

Bogie

[machine shop tom]

Originally Posted by oldbogie

About .040 if you bother to measure.

Bogie

I did.

Did you?

tom

[dirtinla]

As soon as the new parts come in I'll take careful measurements of the old valves vs the new valves and report it here...

Any particular measurements that I should be most precise?

BTW This is a .450 lift custom cam

Thanx

-=Fred=-

[machine shop tom]

Originally Posted by dirtinla

As soon as the new parts come in I'll take careful measurements of the old valves vs the new valves and report it here...

Any particular measurements that I should be most precise?

BTW This is a .450 lift custom cam

Thanx

-=Fred=-

If there were any difference, it would be from the top of the keeper groove to the valve tip. I didn't find any appreciable difference there.

tom