Crossfire to carburetor
Thread Starter
Cruising
Joined: Feb 2005
Posts: 13
Likes: 0
Where do I start.... Does the computer do anything anymore? The distributor has been replaced with one that doesn't have a plug to communicate with the computer. So, the fuel pump relay doesn't work or the cooling fan relay (just to name a few). I've wired the fuel pump relay to the ignition power wire. Now, the pump runs all the time when the key is on. I'm trying to figure out what to do about the cooling fan relay- it's not getting power from the computer to turn on the fan. Also, the cruise control servo is gone. Is it not possible to have cruise with the carburetor? I have a plug hanging out near the computer on the passenger side of the center console with 4 wires- pink/black, pink, black and orange. I don't know what plugs into it- it looks like it should be some kind of relay. Unfortunately, so many things have been unplugged or removed, I'm having a hard time figuring out what's what. This is just the beginning.... Thanks in advance.
Melting Slicks
Joined: Sep 2003
Posts: 3,326
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From: I live at www.domesticlugnuts.com I sleep in PA
Does the computer do anything anymore?
I'm trying to figure out what to do about the cooling fan relay- it's not getting power from the computer to turn on the fan.
Also, the cruise control servo is gone. Is it not possible to have cruise with the carburetor?
I have a plug hanging out near the computer on the passenger side of the center console with 4 wires- pink/black, pink, black and orange.
Do you have the car running yet. Other than the Intake, Carb and Distributor, did they do any other chages that you know of.
Thread Starter
Cruising
Joined: Feb 2005
Posts: 13
Likes: 0
Unfortunately, the dash isn't working either. I did some resoldering on it, and now it comes one, but it doesn't work. Do you recommend anyone to rebuild it? The fan works, but somebody cut the black/red wire to the fan and put a jumper on it for power. I've replaced the relay. As far as I can tell, there are no other modifications. I've just got the car running, but it's running pretty rough. It has a Holley 4-barrell- is that okay for this car? Any suggestions on initial adjustments? How did you wire your fuel pump relay? Does the carb increase horsepower over the fuel injection?
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Go to the bottom of this page-where it says pages 1-900 or something, start checking, there was quite a discussion about this within the last week or two.
Holley is a great carb. putting the right size on is the key (I think 650cfm is probably right) depending on any other mods you intend.Some people will say you'll lose MPG, ease of starting etc. and for every day driving and going back in time- their most likely right.But if you'll notice-most all the monsters are running carbs.
Rich and Lisa and others on the forum have done this.So their probably your best sources.
Holley is a great carb. putting the right size on is the key (I think 650cfm is probably right) depending on any other mods you intend.Some people will say you'll lose MPG, ease of starting etc. and for every day driving and going back in time- their most likely right.But if you'll notice-most all the monsters are running carbs.
Rich and Lisa and others on the forum have done this.So their probably your best sources.
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Originally Posted by Rich & Lisa_84
Quote:
I'm trying to figure out what to do about the cooling fan relay- it's not getting power from the computer to turn on the fan.
The cooling fan relay should be lookig for a ground. Mine gets this from a temp switch located between the 6 - 8 cylinders. You can pulls this wire and attach it to ground and then the fan should run when the key is on.
I'm trying to figure out what to do about the cooling fan relay- it's not getting power from the computer to turn on the fan.
The cooling fan relay should be lookig for a ground. Mine gets this from a temp switch located between the 6 - 8 cylinders. You can pulls this wire and attach it to ground and then the fan should run when the key is on.
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Race Director
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Race Director
Joined: Sep 2000
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From: The Top of Utah
Which relay? Although the carb conversion negates a lot of it's value, the Factory Service Manual, will at least help you understand how it DID work and provide you with a complete wiring diagram for the whole car.
Also, the computer controlled the TCC. You will have to be sure that has been provided for.
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Also, the computer controlled the TCC. You will have to be sure that has been provided for.
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Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by Atarii
I'll have to get the manual- right now I'm working off of wiring diagrams from shopkey. I have no idea if the TCC solenoid has been rewired. What inputs does the computer need to control the TCC?
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Pro
Joined: Apr 2003
Posts: 552
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From: Oz
Originally Posted by CFI-EFI
Just to elaborate, slightly, the ECM is not involved in the fan operation, on an '84.
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Melting Slicks
Joined: Sep 2003
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From: I live at www.domesticlugnuts.com I sleep in PA
Fuel pressure should be around 7psi +/- 2 psi depending on carb.
.
When I disconnected my ECM, My dash went blank. When I reconnected it, everything came back on.
Nor is it required for the digi-dash to operate. The only signal that comes from the ECM to the dash is the MPG display, and that won't work once you have a carb anyway
When I disconnected my ECM, My dash went blank. When I reconnected it, everything came back on.
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Ok I did this conversion and there is a lot of misinformation out there. The only function the ECM will have is to run the FP and the TCC lock up both of witch can be done without it. If the Fuel pump isn't running jumper the ALDL and it will run (I THink its pin G but I am out of the country and cant check. As far as the TCC lock up there is no engine data needed on the 84 just the trany and brakes are used. THe ECM has no efect on the dash, I ran my 84 w/o a ECM for a year. If you get a lock up kit and wire the FP relay enable wire to ING 12V everything will work without the ECM and it can be removed. You still need the sensor wires and sensors Oil Temp. Oil presh, Temp, and Fan sw sending unit. You will need a FP regulator to set the FP aroung 6-8 PSI for the carb a T between the feed and return line with the regulatror on the return side works, Hope this helps as I am using dial up but will be back in the states next week. THe thing I did not know is that the ECM will still lock up the TC on the 84 as long as it has power ground and the trany wires, it would have saved me $80 that I spent oin the kit, Again the ECM has no effect on the dash other then MPG everything else is a sensor and it does not go through the ECM
Melting Slicks
Joined: Sep 2003
Posts: 3,326
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From: I live at www.domesticlugnuts.com I sleep in PA
Then when it warms up, I need to get under the dash again and find out what wiring has been changed by the guy before me. Because when I unplug the ECM, my dash goes blank. Thanks for the info.