Recently purchased an 81 z28 and was wondering what performance mods I could do to yield the best performance gains?

 

A little info on your drivetrain, and what intake, carb, exhaust etc. you have now will help people help you.

 

Wow! If its stock. Like factory looking under the hood. Carb,intake and headers. Then drive it.

 

The car is bone stock... Wondering about a carb and intake if so what kind? Also anything else you can think of product/brand.

 

Bone stock I'd use a 600-650 carb, and small tube headers of 1 5/8" primaries. I'd also back that with a true dual exhaust in 2.25" or 2.5" all the way out. Several choices for intakes, but since it's stock I'd stay with a dual plane plenum on whatever brand you get. Weiand, Edelbrock, etc. are all equally good.

 

A Performer EPS will fit under the hood without any major issue. A Performer RPM should also fit too but some people have issue getting an air cleaner on there. I had a RPM Air Gap under the hood of my '80. But I have solid Moroso motor mounts. I'm still not sure that changed the height. Like Val said. A 600-650cfm vacuum secondary carb. Hedman makes some of the best fitting headers around for our cars, with a small block at least. Just about every exhaust manufacturer on the planet has a kit for our cars now. I have a Magnaflow 2.5" with x pipe. It's not on but has been test fit and looks to be pretty easy to do. Then there are Pypes, Flowmaster and even Summit has a decent duel set for low dough.

Your car has a "computer" that controls spark advance. The dizzy needs to be ditched for a regular HEI with a vacuum canister. If you can get rid of the vac lines under the hood do it. There are just too many to keep looking good in my mind. I would keep the charcoal canister hooked up but thats about it. A new intake would go a long way here. Vacuum advance, booster, and a PCV hose are all I use.

Good luck.

 

One thing to keep in mind with performance changes/upgrades; does your car need to go through environmental testing? If you have testing and inspection in your area, you need to ensure that any changes you make wont cause your car to fail inspections or testing.