dual exaust on an 82
 

well i got my new headers on my 82 tonight and while i was under there i noticed the crossmember and the stock exaust on the right side. how do you run dual pipes around the crossmember on an 82. do you go under it.? didnt the old vettes have 2 holes in the crossmember for the exaust to go thru.:(

My '79 has 2 but i think it was the last year to have the dual holes....

Mid America for one offers a kit that runs both pipes to the passenger side hump. Their part no. 603-866.

Mike

I'm curious how much more performance you get with the new headers. How did the computer react to adding them?

:lurk:

You can run duals in the stock position (as the MA system does) but you can also modify the x-member. If you look at the p. side you'll see that the x-member has a scallop (think that's the right word?) cut out of it. If you cut out an arc from the x-member on the d.side, weld a curved plate over the cut, grind it to shape & slap some paint on it, you'll then have enough room to run the pipe under it, just as is done on the P side. I've got a BTO x-member on my '81, but the principle is the same. What I found was that the limiting factor in ground clearance is the d.side floor pan (deeper due to the electric chair!). With 2 1/2" duals run under both pans I've got 3" of clearance directly below the d.side floor pan.

Texas: Even though mine isn't an '82, it still has a confuser. I found that fitting dual pipes really woke up the motor but at high rpms the power tailed off. It feels like the engine is being strangled ie. just like every other engine from that era that I've de-smogged felt like with stock exhausts, etc. The Headers I fitted made no dfference (that I could notice) in normal driving, but at high rpms the motor feels more alive. I've no doubt it could be improved even further as the heads themselves are probably restrictive. Another difference is that the manifolds on the '81 (& '80?) have a 2" restriction in them, whereas the '82 manifolds have a 2 1/2" restriction (so I've read - I've never seen any). If the '82 manifolds aren't as restrictive then you'll probably not notice as much difference as I did. Other advantages with Headers are that there's now a much nicer sound from under the hood &, being ceramic coated, cabin temps have been reduced.
The stock Q-jet & computer had no problem with Headers but I did need to change the secondary needles to richen it up a bit. It initially felt slightly flat (weak) at higher revs, but after following Lars advice on what rods to fit (DA in place of the stock CH) it feels & sounds great. Haven't a clue what would need doing to the '82 system.
:cheers:

I just converted to Headers and Duals on my 78...
 

I kick myself for not doing it sooner.

It definitely improved the Grin Factor (performance)

I used to hear the carb when I got on it. Not no mo.......:D :D

The hard part was getting the pipe bent up to go from the collector, around the trans, and through the hole in the crossmember on the drivers side.

After that the passenger side was pretty easy.

Thank God I have a talented friend with all the equipment to get the job done.

We had true duals installed on my Dad's 82. We got the crossmember from a early-mid 70's car with the two holes and had that installed. Exhaust fits nicely, even have an X-pipe crammed in there. :)

i've had mine run under the crossmember for many years, no problem..

pictures dammit pictures:toetap:

Not to hijack this thread - I hope this assists the poster... Did you alter your pre-80 crossmember to fit the two through-bolts? I can only get the 4 bolts in that go into the frame from the bottom, but the 2 through bolts won't align. wonder if it's okay not to hook those 2 up? Otherwise I need to cut and weld the Xmember.

Sounds!?
 

hey! can ya post some sound clips of those duals? and let me know what mufflers you're using? I want low-and-rumbly, just not loud-pissed-off-neigborly....sooooooo many dang muffler options...:ack:

I'm not sure exactly what was done to the crossmember, I purchased one and the exhaust guy made it fit. I'm not positive, but I do believe they altered the crossmember holes somehow to make it fit. I got the impression that it was no big deal to make it work.

First off the 82 has a lower seat pan for the electric drivers seat, so even if you get an earlier cross-member the pipe on the drivers side is going to be lower.

What I did was run the pipes down the passenger side in the stock location, it was a great place to remove the cat and add a homemade Xpipe...

http://temp.corvetteforum.net/c3/des...g//header7.jpg

The BTO x-member that I fitted to my '81 had a problem with those through-bolts. The X-member was apparently designed for the pre '80 model & all I needed to do was elongate the holes in the ears (with a file) until I could get the bolts through. If there's enough "meat" on the ears of the stock pre '80 x-member you should be able to do the same.
Pic of my exhausts showing the BTO x-member.
http://i41.photobucket.com/albums/e2...ul/exhaust.jpg
You should be able to see that the pipe under the drivers floorpan is slightly lower & that the clamps have been positioned to give the greatest clearance. Occasionally it decks out on speed bumps but the clamp is taking the punishment (when there's enough metal ground off of it I'll just fit another!).
I did consider running both pipes down the p.side as Dawg has done & also making an X like he did, but the amount of bending, welding & general frigging about put me off. Plus, there'd be more bends to disrupt gas flow, unequal length pipes, etc. Doing it like I did means that once you've sorted the x-member you only need 4 bends in the entire system & get an unrestrictive route for the exhaust gas. I wouldn't recomment fitting Monza glasspacks on the end if you want a quiet life :D
:cheers: