I'm going to do the swap and have a few questions.

1) Use the same rockers and push rods?

2) My Q-Jet has an exhaust heated choke, The vortec heads do not have that provision, can I convert my carb? if yes how

3) Are accessory holes the same?

Any other tips would be appreciated.

Thanks guys. Lee

 

1) Yes, so long as the rockers are either self aligning, or if you have guide plates. However, if you don't have self aligning rockers, you will need guide plates and that requires hardened push rods.

2) I understand that there is an electric choke kit available...maybe PM Lars for more info on that kit.

3) Yes, the accessory holes are the same...even size.

You'll want a set of Fel-Pro 1255 gaskets. They are good and thick and have dual bolt patterns. You can order them through most local auto parts stores. Use a 3/8" thick bead of high temp silicon for the end seals.

Depending on your year, you'll probably have some issues with a temp sender. The holes in the Vortec heads are smaller than your stock sender so to make your stock sender work you'll need to drill and tap the hole for the larger design. You can't just buy a later model sender because the resistance is different and you won't get an accurate reading.

The Vortec head swap will give you the best results if you pair it with a cam and lifter swap too, and it's also a good time to replace the timing set and replace the oil pan gasket with a new Fel-Pro one piece design.

Finally, if you go ahead with the timing cover and oil pan you might as well change the rear main seal to get you extra time in case your stock rear main seal gives out.

 

Durango Boy, Thanks for the reply. I have a fresh short block with flat tops and a comp cams 268H. The current heads are plain Jane 76CC. The vortecs should give a nice boost. I found an old thread were Lars recommends Edelbrock part number 1932 choke kit so that's easy.

Are the rockers that come with the vortec heads self aligning or do I need to go after market?

Lee

 

If someone is supplying you with rockers as a kit with the heads then I suppose they must be self aligning. That's a good question for your supplier.

 

You can tell self aligning rockers from regular stamped rockers in that the tip that touches the valve stem has rails on the sides that keep the tip from sliding side to side off of the valve stems. You can check your own rockers...they 'might' be self aligning. If not, they can be bought cheap. Buying self aligning rockers is cheaper than having the heads machined for guide plates and screw in studs. You also would have to buy hardened push rods and they are not very cheap.

 

I hope this isn't a Homer Simpson "DUH" .... The Vortecs and the stock intake manifold do match up..

 

Oh, and check the cam sheet and look for minimum spring pressure and lift. The stock Vortec spring setup will only take .470" max. If your cam has higher lift you need new springs and some work to get them to fit.

 

I have a vortec intake already.

Cam is 454 E/I so OK there.

$55 for self GM aligning rockers on summit

Thanks all for the tips and comments