Since these were originally plastic, many are now bowed down, cracked or warped due to age, heat and tightening over time. This can lead to vacuum leaks. Our version is made of aluminum to match the appearance of the throttle body and upper intake plenum.
We offer two versions of this reproduction vacuum block: One is exactly like stock. The other is identical the Turbo Trans Am and has an additional vacuum port on the driver's side for a vacuum line for vacuum brake conversions. It comes with a plug in the additional port, you will need to purchase your own fitting for the standard 1/8″ pipe tap.
Each vacuum block comes complete with new stainless bolts. Each vacuum block has five metal screw-in fittings, so they will never break or bend.
Because your stock block is plastic, this is something you will want to replace soon. Most of them are warped by now. I don't think the plastic one is available from GM any more.