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What mods to do??



I bought an 81 4 speed about 5 months ago and have been spending money fixing what was wrong with it (complete brake job, broken Z bar, replacing leaking heater core, etc) My next project will be getting the front end tightened up, then a new clutch (maybe a dual friction unit) after that I want to put true dual exhaust on it with dual cats to stay legal at the same time I'd like to go with a full legenth header but keep in mind i have to keep all the emissions stuff. It seems that there is some sort of tube going to my cat is that something I am going to have to put a T on? Also what parts am I going to have to buy to put true duals on it? I know i need a dual hump transmission cross member. I am also trying to decide what muffler to put on it. What does everyone suggest?
I forgot something

I forgot to mention that untill I am able to put some money into my 62 Chevy II the Corvette is my only transporation
they make a cross over pipe for your exhost that is supose to work real well. It will get you much closer to a dual system. I peraonally love the flowmaster sound they make a great 40 series for you !! If you do go a head with the headers I definitly woukd get something with a heat coating. I didbt I ave two set of wrap on them and they still are hot. It may be just because I droped the air punp and all the crazy stuff around the factory headers.
The 'tube' you're refering to comes off of the A.I.R. system (air pump). It was there to assist temp increase in the cat. I think you can safely block it off. There's a diverter valve in the A.I.R. sys that bleeds off excess air discharge.
You'll find some good quality 'high-flow' cats avail out there that don't require the old 'pipe'. As for mufflers, I recommend the dynomax line of products. They flow well and have a great note too!
If I remember correctly, your crossmember should have 2 holes for exhaust passage, up to 2.5".
For complete exhaust sys: headers, gaskets, exhaust pipes, cats, hangers and mufflers installed at rear of sys. Just watch that the cats are given enough clearance from the floor pans and other components, they run real hot!
You'll have no prob passing emissions with a well tuned engine, and true duals with cats.
Best of Luck -Dave
Thanks Dave

I've looked at my crossmember and I don't see any holes just a spot where there is kind of a hump where the exhaust on the one side goes under.

Also I am looking for some wheels, maybe reproduction maybe something that's just simular but I want to go with wider wheels but I want to retain the look of the aluminum wheels that came on the car. Any Ideas?
I am finding it hard to believe that your car is still running hot with the thermo wrap.

I boought some wrap from thermo-tec and wow what a difference. The heat radiating from the engine bay is a far lot less than before. Even the mechanic that did the rebuild was impressed.

I do agree that if i could do it again I would buy the ceramic coated headers just cause the wrap has some issues as well, such as rust. I knew it was only a temperary thing so i went with it.

It's been a # of yrs since I've seen the underside of an '81. If you only have a 'humped' x-mbr, I think (if it's auto trans) that it is bolted-in for an easy swap out.
As for wheels, do a search for corvette whls or something similar. I've seen some good looking 'torque thrust' whls that kept the vette theme without looking like bicycle whls. -Dave
the crossmember is "humped" but it's a 4 speed and it looks like it's a bolt in so it should be easy enough to swap out with one that will take dual exhaust. Also on the wheels I want something that looks as much like the wheels on it now if not exactly like them if I can get it that way.

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