hey ever one,
in pretty new to this forum, have a couple of questions. i have a 82 vette that i rebuilt the motor and TCI 700R4 trans and replaces the rear gears with 3.70's. i took the crossfire injection off and installed a intake and carb. i choose an edelbrock intake and avs carb. since i took the crossfire off i had to relocate the throttle cable and the tv kick down cable, bought a univerisal bracket from local store. the trans doesnt shift properlly, after playing with the kick down cable for hours. was wondering if they made a good aftermarket brackets to buy to help solve this problem. and was also in the market to get headers and going to buy tru daul exhaust system, was wondering how low the long tube headers hang wondering if i will scrape on the road. also when driving my car my gas gauage needle goes crazy but when sitting still its fine dont know if its a ground or a hot lead. sorry if u heard all these questions before.
thanks ken

 

Get ahold of BTO Overdrives and they will set you up with a TV made EZ kit which includes a proper geometry TV throttle plate adapter and a spring made just for this.

Also recommend getting a pressure gage and use it in the 700R4 pressure port on the driver side of the tranny when you make your TV adjustments. Dont want to fry your new tranny. There is a science to it.

TV cable length also has a role, I have found.

 

Brent knows better than I do about modifying an '82 because he's been there, done that. I've got some experience with long tube headers and true dual exhaust on an '80-'82 though.

I have ceramic coated Dynomax long tube headers from Summit on my GM 350 HO crate engine in my '80.



Yes, they have less ground clearance than stock but not so much that you're going to scrape them on speed bumps or anything like that. If I scrape my Dynomax headers driving over something, then I've scraped a few other things too such as my Steeroids rack & pinion steering, oil pan, traction bar, etc.



If you switch to long tube headers and true dual exhaust, you will have to route your drivers side pipe nearly straight back like the passenger side because the bend to get from the left to the right side from the left header will be too sharp.

To get enough clearance under the drivers side pipe, you will have to make a very simple modification to your front crossmember that looks like this:





Filled in with a length of 3 1/2" exhaust pipe:



...and finished:



Yours could look better than mine because I did mine in 3 lessons learned.

 

for the dual exhaust i was going to go to mid america they have a true dual pipe set up that doesnt envolve cutting the cross member. i really dont want to do that nor have the tools to do it. it only goes for 230 for stainless steel. and thanks you very much for the pictures of your car.

 

Check to see if it will work with long tube headers like you mention in your original post. If it's the same kit I tried, it won't work. You may have to give up those headers to use the MA dual exhaust. I'm not sure though. I had the MA dual exhaust with stainless steel block hugger headers that melted my poly motor mount and fried 3 sets of expensive spark plug wires. I know others here on the C3 CF have the MA dual exhaust. Maybe they will chime in with their headers.

 

Yes Sir; I bought a complete set of exhaust for my 82 which goes back on one side, with the equalizer, no welding, I did use stainless band clamps in lieu of u- bolts. Hooker I think were the headers they had for them, Which I used 2 1/2 inch factory cast iron manifolds, off of 300 HP old cars, I think Corvette Central and Eckler's. both have them in stock ready to ship. It eliminates the guess work with the cross member and the power seat fit. Have a great one. Gene

 

I checked the MA website and noticed that the aluminized exhaust system is $230 and the stainless steel exhaust system is $300. Neither system will fit on long tube headers. They are vertical at the flange, so they will only fit on stock ram horn exhaust manifolds - 2" for '80-'81 and 2.5" for '82. A custom exhaust shop could probably modify them for a short header though, for a fee, of course.

I noticed the MA true dual system does not include a catalytic converter, thus the statement, "Tech Note: For off-road race use only. Never to be used on the highway." (Yeah, right.) I don't know if that matters where you live or not.

If you are switching to true dual, I recommend you choose some good low restriction mufflers too so you don't loose what you gained from the dual system.

 

Easiest thing to do with the TV cable is to take it to a trans shop. They will supply the cable and properly adjust it for you. I did the same thing with my '82 and it cost around $120, money well spent! I too did the same engine mods with my crossfire 2 years ago. I do have a question for you. You replaced the intake and a carb? You will also need new free flowing heads! The most restrictive part of the crossfire set-up is the restrictive heads! Good luck.

 

The TV cable with help correct the shift points, but it won't help get the lockup function back in the transmission. That was part of the computer controller's duties. Now that you 'ditched' the Cross-Fire stuff [not sure why you wanted an '82 if you didn't want the CFI system], you'll need to get a special transmission controller box that allows the 700R4 to work as intended. Check to see if lectriclimited.com sells them.

 

"TORQUE CONVERTER LOCK-UP SWITCH UPDATE KIT, use with 700R4 or 2004R automatic trans. EXCEPT 4L60E or 4L80E. Completely externally installed kit allows for automatic operation of the torque converter lock-up (overdrive) without installing the computer!!!! Kit includes instructions."

I saw they have tach filters and printed circuit boards too. That's a good vendor to add to your Favorites.
Letric Limited Inc.

 

yea i was going to modify the tru dual system so they will allow long tube headers, and also i have flowmaster 40 series mufflers. so i hope it will be free flowing enough. as for the heads i do have the stock heads still they have been decked and milled but still stock valves. dont have enough for after market heads yet lol. another question some one said that since i took my computer out my trans wont lock up. i have a tci street fighter trans. how would i know if it is locking up or not.. i do have over drive when driving on the high way tho.
and thanks for all your guys help.

 

That is exactly what I tried, but it won't work. Here is a picture that shows how the MA true dual exhaust kit lines up with the collectors of long tube headers.



Imagine the bend you would need to mate the header to the MA pipe on the drivers side. It doesn't work. I tried it. I would have saved hundreds of $$ and had a much nicer true dual exhaust if I had just put on the long tube headers and had the guys at the Muffler Doctor make custom pipes in the first place.

Now, you may be thinking, "I COULD compromise and use the MA true dual exhaust with block hugger headers and save a few bucks." That's where I started. Here are the stainless steel block huggers I tried:



Yes, the exhaust shop was able to connect them to the MA exhaust with some simple mods, but I paid elsewhere and otherwise. Take a look at the block huggers. Note that the collector is straight down from cylinders 3-5 and 4-6. Then think about what is just forward and below cylinders 3 and 4. That's right, motor mounts. I put in some really nice poly motor mounts when I installed my GM 350 HO crate engine. Too bad the block huggers ran less than an inch from the motor mounts and melted the poly from the motor mounts.

Then there was the spark plugs and wires. I couldn't install or remove spark plugs 1,2,7, and 8 with the headers on. Even so, once the spark plugs were in and the headers were on, the headers fried the plug boots on 1,2,7, and 8 of 3 sets of spark plug wires in 2 years of about 1200 miles/year. The boots cracked and the spark would jump from the cracked spark plug boot to the header - the path of least resistance - even with woven fiberglass boot covers.

The cross member mod is easy to make using an air compressor and a 3" cutoff tool. The Muffler Doctor had scraps of 3 1/2" exhaust pipe laying around they were glad to weld into the cross member cutout. I ground off the excess pipe and smoothed out their welds before finishing with high temp primer and black paint. I drove it back to them with open headers (loud!) to have them bend pipes and install.

I didn't think of an H-pipe ahead of time, so they made one. If I had thought of that, I would have ordered a universal 2 1/2" H-pipe or X-pipe from Summit and let Chris install that too.

The lessons above cost me about $600 more than if I had just done it right in the right in the first place: long tube headers, OTS H- or X-pipe, custom bent pipes, high flow mufflers and nice chrome tips welded on, all tightly tucked up tight where exhaust pipes should be.

Well, that's my experience. However, there is probably some guy here on the C3 CF who has long tube headers, MA true dual exhaust kit, and absolutely no problems.

Having typed all that, it's your car and your decision.

 

I had a new trans put in mine 700r and the mechanic changed the lock up function from electronic to mechanical. I do not have any switch that I keep reading about. Not sure if worded it right. Told him the CFI engine was going away and I would be going old fashion with no computer ECM. He installed a nice shift kit and told me to bring it back with the new engine to adjust the shift points. He also said he would advise me on the TV cable set up.

As for the exhaust mod above from MN80, I like that, sure makes a nice clean look. Looks like some fancy cutting and welding. Buddy of mine has a welder and plasma cuter, etc. Wonder if he could do that mod for me..
Also can you just get cross member from an older vette? Do they fit?

MN80, what are the dimensions of that cut? How wide and what was the depth you cut. I guess I need enough for a 2.5 pipe, correct? Is that what you have?

 

Another thing to note. You mentioned ditching the computer but no mention of a new Dist. -- you do know it was CC controlled also. You need an old school vaccuum adv dist.

How do you like the 3.70's with the 700R4 ????

 

Just a note: The old cross members do work on 80 and back, with you elongating the holes. but the left floor board is 4 inches deeper on the cars with power drivers seat. Which I think only came on the 81 & 82. The set-up I bought from C. C. bolted in without any mods. on cross member. It did leave clearances, to service the automatic trans filter, without having to drop the pipes. I'm sure the local muffler shop could make you a set to fit, but by using the stainless steel band clamps, I can take my set up off and on without going to the muffler shop, A whole lot better set up than welding. Have a great day. Gene

 

Just another note: you can leave your computer in place, just pull the two fuses to the throttle bodies, change your dist. of course, The trans shifter will still work, and the speed control to your cruise control will work, as well as the 4 #'s Oil sensor, to the fuel pump will still work.. Peace to you all. Gene

 

Neither the cut nor the welding is fancy. They are actually quite simple. I made the cuts with a basic 3" air cutoff wheel in 30-45 minutes and another few minutes to clean it up with an angle grinder.

I used a piece of 1x4 wood (3 1/2" wide) for the pattern with a 3 1/2" half circle rounded end. Then length of the piece of wood was the distance from the floor to where I wanted the top of the hole to be. That's how I made the cut in front the same height as the cut in back of the cross member. I used the piece of wood as a stencil and sprayed around it on the cross member to mark the cut in front. Then I applied masking tape on the bottom of and perpendicular to the cross member to mark where the wood stencil should go on the back of the cross member and sprayed again. The result is shown in the third picture.

I made the cuts with a basic 3" air cutoff wheel in 30-45 minutes and another few minutes to clean it up with an angle grinder (fourth picture). Then I welded in a half section of 3 1/2" exhaust pipe into the hole and smoothed that with an angle grinder too (fifth picture) before priming and painting it (sixth pic). The 3 1/2" cutout leaves 1/2" between the fill piece and the 2 1/2" pipes I have.

The muffler shop welded an exhaust pipe hangar on the back side of the cross member.

You can see how high I cut into the cross member in the third and fourth pictures by looking at the cut compared to the seam.

I designed the cross member mod to give me the same ground clearance as the stock exhaust on the passenger side. As built, I have 1/4" more ground clearance on the modified drivers side than the stock passenger side.

This mod is actually quite simple when you think about it. Someone good with a plasma cutter and a welder could do a better job than I did.

 

Yeah, I am going to a normal Distributor with vaccum adv. I also read about removing the two fuses for the CFI. My other decision is to mod the in tank fuel pump. I am going with a mechnical pump and will have disconnect electric the fuel pump. I think I am just going to remove it and put a new fuel filter sock in its place. Or just by an 1980 sending unit.

Doctor Gene, do mean 80 and older or they work on 80-82? Cross members? Are these for sale, never really researched them.
I would like it to where i can take the exhaust off if needed.
MN80 thanks for the specs, I may pick your brain more about this later. My welder contact says I will need a tig instead of mig welder.
I have to say that last pic of the exhaust all running on the passenger side, just does not look good... Like a mule's a$$ sewed up with grapevine....

82 corvettekid, I would talk to the trans shop or BTO as suggested above about the TV cable.

 

Yes Sir: I enlongated the 4 holes in the cross member, to meet nuts in the bottom of frame. The inside frame bolts, which go in the inside, worked the way they were. all 82 had electric seats, is my understanding, which had the floor board 4 inches lower on the drivers side. I don't know if the 81, had that drop or not. I used the Walker S. S. Mega clamps, they make both butt & lap, They don't kink the pipe, like a U clamp and when you need the pipes down, they come right apart. Summit has them .. The dual system fits & looks just like it came from the factory, going down the riders. side. I put them all together without any help. If you need any other info. Let me. know I will try. Gene

 

Hmmmm. I don't know why your welder thinks the mod needs to be welded with TIG. I used MIG with no problems.