I'm rebuilding a 1976 / 77 Chevy 350, with a 2 barrel carb. I carefully put the intake manifold on so i'd have no leaks, then discovered that I didn't put the restrictor in the right side intake manifold gasket..... after I found the little pouch and instructions in the gasket set! What's their purpose, and what's going to happen if I don't put the restrictor in??? Some years and models have no restrictors, some have them on one side, and maybe some models have them on both sides. Are they for the emission controls to work correctly? Will my carb get too hot without the restrictor? The engine is going in a 64 Chevy pickup, so the emissions aren't too big of a concern. Thanks for your help! Tom
Are you using the stock intake or an aluminum aftermarket. Some aftermarket intakes are machined with the chamber blocked off.The restrictor your refering to used exhaust gas to heat the area of the intake where the old spring type mechanical choke was located. Chevy built many engines with off the shelf warehouse parts trying to use them up. By this time your engine had an electric choke and the chamber was blocked off. When the engine is cold, the open chamber won't be noticed. But when the engine is warmed up, it could cause problems :ie vapor lock in the summer, hot fuel temp resulting in poor performance. Remember a cooler air/fuel charge makes more power. If it were mine I would take the intake back off and install them with a new set of gaskets. If not its going to bug you.
Intake restrictors David, thanks for you answer. I have a stock manifold, although I believe that it's a 1976, bolted onto a 1977 block, as the intake was orange, and the block blue. The Intake has an EGR and a heat tube inside the intake, for the choke, if I remember correctly. Guess I beter buy a manifold gasket set and start over. Thanks, Tom
Intake Chevy orange was replaced with Chevy blue around 1972. Upgrading to a Holley 4 barrel with an Edlebrock proformer intake would make the engine breathe better also, plus add some low end torque.
I wouldnt bother with the restictors they still have a hole in them and they really do not make that big of a difference,the factory does not put in restictors so I would not start over.
