I want to gut the breather box on my 87 gta but i dont know where im supposed to cut.

 

If it's a stock '87 air cleaner assembly, then it breathes from the inside out, meaning, the air comes in through the middle of the air cleaner and is sucked outward, so you can't "gut" the can. You can cut the plastic "box" off the top of the can to directly expose the middle of it, but that's about it.

The '85-'87 assembly is poorly-designed and poor-flowing, and the best thing to do with it is get rid of it and replace it with the air cleaner assembly from an '88-'89 car, if you want to keep a 'stock' air cleaner assembly. But if 'stock' isn't important, then make (or buy a) "cold air intake" assembly that replaces the entire stock assembly.

 

stock doesnt matter but wouldnt a typical cold air intake assembly just pull all the hot air from the engine and cause no benefit?

 

A "cold air intake" for a Firebird would be set-up to draw air from the fenderwell, so the can or box that houses the filter is aimed and open toward that area. SLP used to make one, but it was expensive. They might still, but I don't think so, but you can probably find pictures of it.

The '88-'89 stock assembly is designed similarly. It's a good one, and it was the major contributing factor to the '88 engine making 5-10 more hp than the '87 engine. But they aren't easy to find. Sometimes you'll see someone parting out an '88 or '89 engine, but those air cleaner assemblies are gone quickly.

Some people who make their own will just put a cone-style filter on the end of a tube, and they'll have the cone situated in a way that will let it draw air from the fenderwell area.

Or another thing people do with their homemade designs is to cut a hole in the engine bay where the air can would normally sit, run the tube though the hole to underneath the car, then attach the cone filter underneath there, and it will draw fresh air in from underneath.

A search would probably turn-up pictures of many examples.

 

I found airflow increased just getting the filter out of the canister. I removed the canister and stuck the air filter on the end of the MAF after blocking one end of the filter. Seat of the pants acceleration felt better. I then replaced the black plastic air routing system with a straight 3 inch tube, but it felt the same as the stock plastic one did. I then changed to a K&N filter using both the black plastic air routing system and the straight 3 inch tube and both felt about the same. Either way, just getting the filter out of the canister made a big improvement.

 

I pretty much did samething, exposing the air filter made a big difference to my 87 GTA.

 

I dont know how hard it would be to convert to an 88 intake if you have an 87, if there are different sensors and such. But here is my set up, I went and took off the stock air canister on my 88. I then took the intake hose to autozone and found a K&N cone filter that fit. I took the screens out of my Maf, and then did the coolant bypass mod on the throttle body, and there is a definite seat of the pants difference in acceleration. Also while you have the intake off, it would be a good idea to clean behind the throttle blades on the throttle body, and also clean off the idle air control valve. If you did all of this to your car you would feel a massive improvement in your throttle response

 

that is exactly what im looking to do. how to i remove the screens from the maf? and whats the best way to do the throttle body coolant bypass the writeup on here is kind of unclear the diagram doesnt realy help much since it doesnt looke like mine haha.

 

will i run into any problems if i just remove the top part of the breather and leave it open with the filter exposed?

 

See below:

You won't run into any problems. It will be just fine.

The screens have aluminum "foil" frames that hold them into the grooves in the plastic housing. Simply take a small thin screw driver or the point of a knife and pry the screens out, working your way around them until they're out. It's very easy.

How does yours look? Unless someone has made some modifications to it in the past, yours shouldn't be different.

Remove the U-shaped hose from the front of the intake manifold underneath the throttle body, and remove the short hose from the side of the throttle body that connects to the heater diverter valve, then simply run a new hose directly from the front of the intake manifold(where the U-shaped hose was) to the heater diverter valve. The route for your new hose is up to you, however you want it to look under your hood. So you're just connecting those two parts together, bypassing the throttle body.

It's probably a good idea to drain some coolant first, but I'm sure plenty of people do it without draining any. So to make a mess or not make a mess is also up to you.