1981 Carb and Computer advice
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Kalway, yes the drop in coil is what I was refereing to, and the drop in chip for the dist. The new coil is rated at 50kv same as yours is, I couldn't find a spec on the stock unit in mine.
Abby Normal
Joined: Dec 2001
Posts: 53,456
Likes: 92
From: Press "2" for English
Originally Posted by a1sensei
I'm not sure what a projection set up is, but you can run a roller cam with the computer. God bless, Sensei
2) you can't run a roller cam with the early CCC. the valve train is too noisy so the computer interprets it as detonation and retards your timing. later computers factor that noise frequency in so they don't have the same trouble
Safety Car
Joined: Dec 2004
Posts: 4,071
Likes: 0
From: San Diego CA
Originally Posted by SIXFOOTER
Kalway, yes the drop in coil is what I was refereing to, and the drop in chip for the dist. The new coil is rated at 50kv same as yours is, I couldn't find a spec on the stock unit in mine.
Here's the one I have that I got for $85 on ebay. It works like a champ.
http://procompelectronics.com/Files/1.html
Thread Starter
Instructor
Joined: Aug 2006
Posts: 134
Likes: 0
From: Apple Valley MN
It looks to me that the distributor was replaced but the cap seems right. There is not a Vac line to it so I suspect I am not getting any advance and it does seem a little sluggish. As I said earlier - the trans seems to be controlled ok, the wires are there for the carb - which means I need to replace the distributor with the correct HEI and then try to hook up the computer. If all else fails I can go back to the way it is. I just need to figure out where to spend the money - I have not priced replacement distributors other than at Eckler's and CCentral.
From one of the other posts - i saw the Ultimate HEI Upgrade Kit at procompelectronics.
http://procompelectronics.com/Files/9.html It may be the way to go?
From one of the other posts - i saw the Ultimate HEI Upgrade Kit at procompelectronics.
http://procompelectronics.com/Files/9.html It may be the way to go?
Last edited by MN81C3; Sep 8, 2006 at 02:31 PM.
Safety Car
Joined: Dec 2004
Posts: 4,071
Likes: 0
From: San Diego CA
Originally Posted by MN81C3
It looks to me that the distributor was replaced but the cap seems right. There is not a Vac line to it so I suspect I am not getting any advance and it does seem a little sluggish. As I said earlier - the trans seems to be controlled ok, the wires are there for the carb - which means I need to replace the distributor with the correct HEI and then try to hook up the computer. If all else fails I can go back to the way it is. I just need to figure out where to spend the money - I have not priced replacement distributors other than at Eckler's and CCentral.
From one of the other posts - i saw the Ultimate HEI Upgrade Kit. It may be the way to go?
From one of the other posts - i saw the Ultimate HEI Upgrade Kit. It may be the way to go?
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
Originally Posted by Older Than Dirt
I think CD is speaking about fuel injection. If you alter any part of the stock engine, cam, rear end, etc., how can the stock prom work correctly with the new setup? Who can program a new prom for an altered setup?
P.S. I know you can't run a noisy timing sets with the computer, but that is the first I have heard of the roller cam causing a problem (I'm sure you know what you are talking about). I run a flat tappet cam with roller rockers with no problems.
Last edited by a1sensei; Sep 8, 2006 at 04:17 PM.
Abby Normal
Joined: Dec 2001
Posts: 53,456
Likes: 92
From: Press "2" for English
Originally Posted by a1sensei
P.S. I know you can't run a noisy timing sets with the computer, but that is the first I have heard of the roller cam causing a problem (I'm sure you know what you are talking about). I run a flat tappet cam with roller rockers with no problems.
Burning Brakes
Joined: Aug 2002
Posts: 1,146
Likes: 10
From: Scottsboro Alabama
[QUOTE=a1sensei] I have new heads, cam, exhaust, etc, etc and mine runs like a scalded dog with stock computer (Hyperchip), distributor (w/MSD box) and carb (with a few mods). God bless, Sensei
That's interesting, I wasn't aware that would work.
That's interesting, I wasn't aware that would work.
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Safety Car
Joined: Dec 2004
Posts: 4,071
Likes: 0
From: San Diego CA
Originally Posted by MsVetteMan
Ha......scalded dog.....computer........naawwwwwwwww
Not with an unmolested stock puter that is.
Not with an unmolested stock puter that is.
Le Mans Master
Joined: Jul 2000
Posts: 6,664
Likes: 162
From: columbia city in
Originally Posted by clutchdust
1) yes, projection is fuel injection
2) you can't run a roller cam with the early CCC. the valve train is too noisy so the computer interprets it as detonation and retards your timing. later computers factor that noise frequency in so they don't have the same trouble
2) you can't run a roller cam with the early CCC. the valve train is too noisy so the computer interprets it as detonation and retards your timing. later computers factor that noise frequency in so they don't have the same trouble
Instructor
Joined: Mar 2006
Posts: 107
Likes: 0
hmm
Did u say it shifts smoothly through all 4 gears? is it an automatic?? I didnt know they had a stock 4 speed automatic in 81, because im looking into getting a 4 speed auto to replace my 3 speed. Also i kept my CCC system and removed the smog pump like the others on here. Its the way to go.
Advanced
Joined: Jul 2003
Posts: 95
Likes: 1
From: Davenport FL
My 81 auto has three gears, but the auto 82s had four and I don't know of a reason that tranny would not fit. I could be wrong of course.
Again, I could be wrong, but I always thought a torque converter was set to change your gears at about the red line when you floored the engine. I have always thought that with pedal to the medal, the torque converter kept you from over winding the engine. I also thought that when you ran a hotter engine, you wanted to change to a higher rev torque converter to delay the shift and to utilized your new maximum power curve. Am I wrong about that?
On the other subject, my Accel HEI distributor has a vacuum line to my Holley carb sitting on my Holly intake. It never ran right until I changed the distributor out to match the new carb.
http://www.mycarframes.com
Again, I could be wrong, but I always thought a torque converter was set to change your gears at about the red line when you floored the engine. I have always thought that with pedal to the medal, the torque converter kept you from over winding the engine. I also thought that when you ran a hotter engine, you wanted to change to a higher rev torque converter to delay the shift and to utilized your new maximum power curve. Am I wrong about that?
On the other subject, my Accel HEI distributor has a vacuum line to my Holley carb sitting on my Holly intake. It never ran right until I changed the distributor out to match the new carb.
http://www.mycarframes.com
Pro
Joined: Dec 2000
Posts: 560
Likes: 0
From: Camino CA
The 4 speed auto trans is a bit longer than the 3 speed, you need a different crossmember, and a shorter driveshaft to get it in there.
The torque converter is like the clutch for the automatics, it doesn't shift the gears, it just lets the transmission and engine move at different rpms. The gear shifting is controlled by fluid pressure, the govenor, and the vacuum modulator.
The torque converter is what lets you stop while in gear and not stall the engine.
The torque converter is like the clutch for the automatics, it doesn't shift the gears, it just lets the transmission and engine move at different rpms. The gear shifting is controlled by fluid pressure, the govenor, and the vacuum modulator.
The torque converter is what lets you stop while in gear and not stall the engine.
Thread Starter
Instructor
Joined: Aug 2006
Posts: 134
Likes: 0
From: Apple Valley MN
Originally Posted by HighHeat303
Did u say it shifts smoothly through all 4 gears? is it an automatic?? I didnt know they had a stock 4 speed automatic in 81, because im looking into getting a 4 speed auto to replace my 3 speed. Also i kept my CCC system and removed the smog pump like the others on here. Its the way to go.
I am a little nervous about getting the correct HEI dist and hooking up the computer. The more I dig – the more creative wiring I am finding. I may just go with a vacuum advance HEI dist and then think about replacing the carb. Bubba replaced the correct dist with an older one without vac advance which is affecting performance. I would like to have the computer working as I plan to drive the car a lot – not as a daily driver though.
Safety Car
Joined: Dec 2004
Posts: 4,071
Likes: 0
From: San Diego CA
If the wiring is really that bubba'd then I'd suggest just getting a 4MV quadrajet and rebuilding it. It really isn't too hard to rebuild them and you can get all the parts you need for a 4MV (pre-75). It'll bolt right up and have all of the vacuum ports and everything that your car needs. After you get a vacuum advance HEI and a non-computer controlled q-jet you can get the B&M TCC lock-up gizmo and you'll be able to run as good as new. You don't really NEED the TCC lock-up, as it'll still function just like a TH350 and it won't hurt anything, just make sure it doesn't overheat.
Drifting
Joined: May 2000
Posts: 1,952
Likes: 6
From: Palos Verdes Peninsula California
Originally Posted by MN81C3
Thanks Sixshooter and Sensei. It sounds like the best thing to do is to try to get the CCC controlling the carb again. The trans shifts through the 4 gears and locks up like it should and the car runs great other than the idle. I have the build manuals and a Chilton’s so I will trace the wires and see what I can find. I will keep you posted.
I have an unmolested 81 with everything hooked up correctly. Shot me a PM if you have any problems and I would be happy to help. Even with the manuals it can get confusing with all the wires and hoses in there.
John.
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
The computer does not have that many wires in the first place, and if you disregard the AIR, EGR etc., there isn't that much left at all. Get an assembly manual (you need one anyway!) and you should be fine. Don't be afraid to pick up the correct distributor. You can get it at NAPA for a reasonable price, and they work well. Don't give up, from the pictures I saw, I would bet your wiring is not that messed up, and may actually be okay. Bubba may have listened to one of the "experts" who like to spout off the myth that you can't get performance with the computer (IT'S A LIE!). He may have just grabbed an old HEI, threw it in and disconnected the rest thinking it would go faster! God bless, Sensei
Safety Car
Joined: Dec 2004
Posts: 4,071
Likes: 0
From: San Diego CA
Honestly I agree with sensei with the fact that you can go fast with the confuser. I don't see any reason you couldn't. I ditched my computer for the simple fact that I didn't want to dive in to such as strange system and figure it out. I went with the tried and true M4M and vacuum HEI and didn't really care about the TCC because I don't go on the freeway all that much. With all of the money I've spent on my non-computer controlled system I coulda paid someone to fix my original system in place. However, I like the old system and it works very well for me, and my check engine lights stays the F off now. 
Basically your options are ditch it and get a new carb, distributor and maybe a TCC lock-up device or keep the computer and get it to work and be happy. The system works fine WHEN IT WORKS.
Basically your options are ditch it and get a new carb, distributor and maybe a TCC lock-up device or keep the computer and get it to work and be happy. The system works fine WHEN IT WORKS.