I own a 1990 Pontiac Firebird Formula. It still has the stock 305cid TBI engine. I am preparing to order the Holley part # : 502-5 670cfm Performance Throttle-Body Assembly and the Holley part # : 300-66 Weiand Stealth Intake Manifold. Should I add a spacer between the manifold and throttle-body assembly. Can you please tell me if this is necessary or if it would be beneficial? If the answer is 'Yes', can you tell me exactly what to get. I know that Turbo City sells a couple of different ones. Please give me some suggestions. Thank you for any help you can give me.

 

What other mods do you have?

 

If you've got room for one and you don't pay too much, go for it. Nothing wrong with them. Just try and baseline performance and gas milage before and after, so you can justify your investment. So far I've only seen spacers work well on stock manifolds or other engines that have too small of an intake versus the rest of the motor.

 

I was thinking the holley T/B is a bit much for a stock 305 or one with bolt ons.