Computer removal on an '81???
Thread Starter
Melting Slicks
Joined: Nov 2005
Posts: 3,323
Likes: 142
From: Green Valley Arizona
Computer removal on an '81???
Thinking about removing the computer from my '81...I know I need to replace the carb and distributor.....the distributor is easy to find...but not so easy on the carb. And also, where is the vacuum source for the advance?....does it come off the carb?
I know others have been here so I am asking for guidance.
Thanks
I know others have been here so I am asking for guidance.
Thanks
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
If you are asking where you get the vacuum for the advance can when you change the 'stock' system out, then you can pull it directly from the intake manifold vacuum fitting or you can connect it to one of the "new" carb fittings that is 'manifold' vacuum. {Note: A manifold vacuum fitting on the carb will 'suck' when the car is idling; a "ported" vacuum fitting will have zero vacuum at idle, but transition to a manifold vacuum condition once the throttle plates are opened a bit.}
Thread Starter
Melting Slicks
Joined: Nov 2005
Posts: 3,323
Likes: 142
From: Green Valley Arizona
Which vacuum source, ported or non-ported is the vacuum advance normally connected to?
Sorry I have to ask this, but it has been a long time since I have had a car that uses a vacuum advance.
I have had my '81 with the CCC system for over 10 years now and was just thinking of trying a vacuum advance distributor to see if there is any gain with the latest engine mods and pehaps the CCC is the limiting factor.
Again, just thinking....
Sorry I have to ask this, but it has been a long time since I have had a car that uses a vacuum advance.
I have had my '81 with the CCC system for over 10 years now and was just thinking of trying a vacuum advance distributor to see if there is any gain with the latest engine mods and pehaps the CCC is the limiting factor.
Again, just thinking....
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
The CCC is NOT a limiting factor. Save yourself a lot of wasted money and:
1. Tune the carb for performance (Adjust throttle plate opening, air valve etc.)
2. Get a hyperchip for ~$125 and set base timing around 12 BTDC.
This will give you everything you could get from a carb and timing. If you want more, spend your money where it will make a difference.
God bless, Sensei
1. Tune the carb for performance (Adjust throttle plate opening, air valve etc.)
2. Get a hyperchip for ~$125 and set base timing around 12 BTDC.
This will give you everything you could get from a carb and timing. If you want more, spend your money where it will make a difference.
God bless, Sensei
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
The CCC is NOT a limiting factor. Save yourself a lot of wasted money and:
1. Tune the carb for performance (Adjust throttle plate opening, air valve etc.)
2. Get a hyperchip for ~$125 and set base timing around 12 BTDC.
This will give you everything you could get from a carb and timing. If you want more, spend your money where it will make a difference.
God bless, Sensei
1. Tune the carb for performance (Adjust throttle plate opening, air valve etc.)
2. Get a hyperchip for ~$125 and set base timing around 12 BTDC.
This will give you everything you could get from a carb and timing. If you want more, spend your money where it will make a difference.
God bless, Sensei
If its true you can run at 12*, I may get a hypertech that runs with the lower temp thermostat so I can run my engine cooler and the comp will still run in closed loop.
Instructor
Joined: Aug 2010
Posts: 233
Likes: 18
From: Monrovia Md
Another CCC 1981 bites the dust -- they are dyeing fast.
WHY do you want to get rid of the computer. The CCC will run the same as any Carb and Distributor combination that you put on the engine. The limitation in the engine is from the CAT and the heads. You can change both of them without making any modifications to the CCC system.
People say the CCC is a pain in the *** when it doesn't work right -- but it usually does not work right because something in the engine isn't working right such as Vacuum leaks, exhaust or intake leaks etc. -- But don't you want to diagnose and fix these anyway.
When I started my 1981 last year after about 10 year rest, it ran like crap -- After a few months of tinkering, I have fixed all the vacuum leaks, and exhaust leak, tuned the carb and the car runs GREAT -- smooth as silk on idle and acceleration . I feel like the engine is tighter and more stable than it ever has been. In my estimate -- the CCC helped me to uncover the problems that were in my engine that need to be addressed. You can blame the computer because it complained, or thank it for helping to diagnose issues that most people would never begin to look for.
God bless the CCC 1981!!! (Soon to be the last?)
WHY do you want to get rid of the computer. The CCC will run the same as any Carb and Distributor combination that you put on the engine. The limitation in the engine is from the CAT and the heads. You can change both of them without making any modifications to the CCC system.
People say the CCC is a pain in the *** when it doesn't work right -- but it usually does not work right because something in the engine isn't working right such as Vacuum leaks, exhaust or intake leaks etc. -- But don't you want to diagnose and fix these anyway.
When I started my 1981 last year after about 10 year rest, it ran like crap -- After a few months of tinkering, I have fixed all the vacuum leaks, and exhaust leak, tuned the carb and the car runs GREAT -- smooth as silk on idle and acceleration . I feel like the engine is tighter and more stable than it ever has been. In my estimate -- the CCC helped me to uncover the problems that were in my engine that need to be addressed. You can blame the computer because it complained, or thank it for helping to diagnose issues that most people would never begin to look for.
God bless the CCC 1981!!! (Soon to be the last?)
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Thread Starter
Melting Slicks
Joined: Nov 2005
Posts: 3,323
Likes: 142
From: Green Valley Arizona
WHOA....hold on there.....I was just thinking....have not actually purchased anything yet....am just thinking.
I have tuned the carb per Lars...as best as can be done with the E4M$ that is.
Car runs good....has Edelbrock Performer 70cc heads, Performer intake and the Luanti 60102 cam, headers and CCC all intact with the Hyper chip. The Hyper chip has been there for a long time as the PROM was dead when I got the car 10 years ago.
I think the engine is still running a bit rich and that is due to the cam, low vacuum and all...which is why I was thinking that taking the CCC out would improve this.
However something I just realized.....the MAP sensor is on ported vacuum....so the CCC is not monitoring vacuum at idle and is not adjusting the fuel mixture due to low vacuum.....
Hmmmmm.....I was thinking incorrectly.!!...
So unless I find the necessary parts at a FREE price....think I will just keep the CCC.
I have tuned the carb per Lars...as best as can be done with the E4M$ that is.
Car runs good....has Edelbrock Performer 70cc heads, Performer intake and the Luanti 60102 cam, headers and CCC all intact with the Hyper chip. The Hyper chip has been there for a long time as the PROM was dead when I got the car 10 years ago.
I think the engine is still running a bit rich and that is due to the cam, low vacuum and all...which is why I was thinking that taking the CCC out would improve this.
However something I just realized.....the MAP sensor is on ported vacuum....so the CCC is not monitoring vacuum at idle and is not adjusting the fuel mixture due to low vacuum.....
Hmmmmm.....I was thinking incorrectly.!!...
So unless I find the necessary parts at a FREE price....think I will just keep the CCC.
Drifting
Joined: Jun 2011
Posts: 1,704
Likes: 27
People say the CCC is a pain in the *** when it doesn't work right -- but it usually does not work right because something in the engine isn't working right such as Vacuum leaks, exhaust or intake leaks etc. -- But don't you want to diagnose and fix these anyway.
God bless the CCC 1981!!! (Soon to be the last?)
God bless the CCC 1981!!! (Soon to be the last?)
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
God bless, Sensei
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
I have actually built a few of these for people.
http://www.angelfire.com/my/fan/MAP_adjuster.html
God bless, Sensei
http://www.angelfire.com/my/fan/MAP_adjuster.html
God bless, Sensei
Burning Brakes
Joined: Feb 2000
Posts: 770
Likes: 285
From: Middleton, Id
Another CCC 1981 bites the dust -- they are dyeing fast.
WHY do you want to get rid of the computer. The CCC will run the same as any Carb and Distributor combination that you put on the engine. The limitation in the engine is from the CAT and the heads. You can change both of them without making any modifications to the CCC system.
People say the CCC is a pain in the *** when it doesn't work right -- but it usually does not work right because something in the engine isn't working right such as Vacuum leaks, exhaust or intake leaks etc. -- But don't you want to diagnose and fix these anyway.
When I started my 1981 last year after about 10 year rest, it ran like crap -- After a few months of tinkering, I have fixed all the vacuum leaks, and exhaust leak, tuned the carb and the car runs GREAT -- smooth as silk on idle and acceleration . I feel like the engine is tighter and more stable than it ever has been. In my estimate -- the CCC helped me to uncover the problems that were in my engine that need to be addressed. You can blame the computer because it complained, or thank it for helping to diagnose issues that most people would never begin to look for.
God bless the CCC 1981!!! (Soon to be the last?)
WHY do you want to get rid of the computer. The CCC will run the same as any Carb and Distributor combination that you put on the engine. The limitation in the engine is from the CAT and the heads. You can change both of them without making any modifications to the CCC system.
People say the CCC is a pain in the *** when it doesn't work right -- but it usually does not work right because something in the engine isn't working right such as Vacuum leaks, exhaust or intake leaks etc. -- But don't you want to diagnose and fix these anyway.
When I started my 1981 last year after about 10 year rest, it ran like crap -- After a few months of tinkering, I have fixed all the vacuum leaks, and exhaust leak, tuned the carb and the car runs GREAT -- smooth as silk on idle and acceleration . I feel like the engine is tighter and more stable than it ever has been. In my estimate -- the CCC helped me to uncover the problems that were in my engine that need to be addressed. You can blame the computer because it complained, or thank it for helping to diagnose issues that most people would never begin to look for.
God bless the CCC 1981!!! (Soon to be the last?)
Drifting
Joined: Jun 2011
Posts: 1,704
Likes: 27
Your not the last! Still running the CCC even with a cam, head work, high flow cat and engine rebuild. Sure the carb took me a while to learn how it operates and tune, but it was fun to learn about it and it runs great now - lays down long black lines if I want, and still passes Ca. smog.
I want to follow in your footsteps!
Drifting
Joined: Aug 2009
Posts: 1,635
Likes: 8
From: Enid Oklahoma
Thinking about removing the computer from my '81...I know I need to replace the carb and distributor.....the distributor is easy to find...but not so easy on the carb. And also, where is the vacuum source for the advance?....does it come off the carb?
I know others have been here so I am asking for guidance.
Thanks
I know others have been here so I am asking for guidance.
Thanks
Burning Brakes
Joined: Aug 2006
Posts: 1,058
Likes: 27
From: Eastern North Carolina
Another CCC 1981 bites the dust -- they are dyeing fast.
WHY do you want to get rid of the computer. The CCC will run the same as any Carb and Distributor combination that you put on the engine. The limitation in the engine is from the CAT and the heads. You can change both of them without making any modifications to the CCC system.
People say the CCC is a pain in the *** when it doesn't work right -- but it usually does not work right because something in the engine isn't working right such as Vacuum leaks, exhaust or intake leaks etc. -- But don't you want to diagnose and fix these anyway.
When I started my 1981 last year after about 10 year rest, it ran like crap -- After a few months of tinkering, I have fixed all the vacuum leaks, and exhaust leak, tuned the carb and the car runs GREAT -- smooth as silk on idle and acceleration . I feel like the engine is tighter and more stable than it ever has been. In my estimate -- the CCC helped me to uncover the problems that were in my engine that need to be addressed. You can blame the computer because it complained, or thank it for helping to diagnose issues that most people would never begin to look for.
God bless the CCC 1981!!! (Soon to be the last?)
WHY do you want to get rid of the computer. The CCC will run the same as any Carb and Distributor combination that you put on the engine. The limitation in the engine is from the CAT and the heads. You can change both of them without making any modifications to the CCC system.
People say the CCC is a pain in the *** when it doesn't work right -- but it usually does not work right because something in the engine isn't working right such as Vacuum leaks, exhaust or intake leaks etc. -- But don't you want to diagnose and fix these anyway.
When I started my 1981 last year after about 10 year rest, it ran like crap -- After a few months of tinkering, I have fixed all the vacuum leaks, and exhaust leak, tuned the carb and the car runs GREAT -- smooth as silk on idle and acceleration . I feel like the engine is tighter and more stable than it ever has been. In my estimate -- the CCC helped me to uncover the problems that were in my engine that need to be addressed. You can blame the computer because it complained, or thank it for helping to diagnose issues that most people would never begin to look for.
God bless the CCC 1981!!! (Soon to be the last?)
Drifting
Joined: Aug 2009
Posts: 1,635
Likes: 8
From: Enid Oklahoma
I still chuckle when I read how great the CCC is after you "figure it out", or "after a month of work". I spent an afternoon getting rid of mine and she purrs like a kitten. Would do it again in a heartbeat, but everyone has thier own opinion. I found an 81 while looking for a late model C3, I knew before I bought it that I would pull the CCC, to each his own. But to say the CCC is as easy to work on as a non comp car is simply nonsense.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
U won't gain much on a modest performance engine by removing the computer..
I recall the computer just controlled the primary side of the electric Qjets. The secondary side is still tunable for performance. Meaning u have to live with stokiometric 14.7 A/F ratio just until the secondaries kick in. So u can still tune richer at WOT. I also believe that all OBD I (and many OBD II) computers become open loop on WOT - meaning they no longer look at the A/F ratio from the O2 sensor to adjust mixture. And they can't anyways. The mixture solenoid is in the primary side of the carb (u can see that for yourself). And u can change the secondary metering rods in less than 5 minutes on any Qjet.
My 2 cents is it would take a lot of performance mods before it would require removing the computer and electric carb.
cardo0
My 2 cents is it would take a lot of performance mods before it would require removing the computer and electric carb.
cardo0
Burning Brakes
Joined: Feb 2000
Posts: 770
Likes: 285
From: Middleton, Id
I recall the computer just controlled the primary side of the electric Qjets. The secondary side is still tunable for performance. Meaning u have to live with stokiometric 14.7 A/F ratio just until the secondaries kick in. So u can still tune richer at WOT. I also believe that all OBD I (and many OBD II) computers become open loop on WOT - meaning they no longer look at the A/F ratio from the O2 sensor to adjust mixture. And they can't anyways. The mixture solenoid is in the primary side of the carb (u can see that for yourself). And u can change the secondary metering rods in less than 5 minutes on any Qjet.
My 2 cents is it would take a lot of performance mods before it would require removing the computer and electric carb.
cardo0
My 2 cents is it would take a lot of performance mods before it would require removing the computer and electric carb.
cardo0
