84 convert to Carb
Thread Starter
Cruising
Joined: Dec 2024
Posts: 12
Likes: 1
84 convert to Carb
Thinking of converting our 84 to a carb. Having LOTS of issues with sensors, ECM etc...
anyone done this and have any first hand experience? Pros and cons?
Carbs don't scare me, have a 65 Fastback and power boats that are carbed. So that im good with. Just want to know what the issues are that I'm maybe not Thinking of.
I know I need an intake, carb, fuel presure regulator, Distributor and may a few ofs and ends...
anyone done this and have any first hand experience? Pros and cons?
Carbs don't scare me, have a 65 Fastback and power boats that are carbed. So that im good with. Just want to know what the issues are that I'm maybe not Thinking of.
I know I need an intake, carb, fuel presure regulator, Distributor and may a few ofs and ends...
Melting Slicks
Joined: Mar 2001
Posts: 2,150
Likes: 304
From: Timra, Sweden
Tachometer signal comes from the distributor and the dash does not share any sensors with the ECU.
Only instant and average mpg inforation is lost. ( and range that is calculated from average mpg and remaining fuel )
You can keep cruise control if you connect the cable from the vaccum actuator. ( controlled by instrument cluster )
AC still works.
You loose lockup on automatic transmission, but that can be connected to 4th gear signal at the ECU connector.
On a 4+3 you loose overdrive control but that can also be jumped at the ECU connetor to work directly from the enable switch.
Use a regulator with fuel return, then you can leave the fuel pump as it is. You need to activate the fuel pump relay and that can also be done with a jumper wire at the ECU connector.
Only instant and average mpg inforation is lost. ( and range that is calculated from average mpg and remaining fuel )
You can keep cruise control if you connect the cable from the vaccum actuator. ( controlled by instrument cluster )
AC still works.
You loose lockup on automatic transmission, but that can be connected to 4th gear signal at the ECU connector.
On a 4+3 you loose overdrive control but that can also be jumped at the ECU connetor to work directly from the enable switch.
Use a regulator with fuel return, then you can leave the fuel pump as it is. You need to activate the fuel pump relay and that can also be done with a jumper wire at the ECU connector.
Pro
Joined: Sep 2024
Posts: 526
Likes: 114
The fortunate part is your 84 already has the crossfire fuel system which puts out a mere 12 psi. I dropped a 60 psi fuel pump in my car and attempted to regulate it down and I couldn't do it so my solution is to grab one of the older fuel pumps that put out low pressure that can be regulated down effectively. I believe the OEM part number is 4099028828. I am still in beta testing (waiting on the pump to arrive) but this should work fine.
On the distributor, I would snag a standard HEI that has vacuum advance as the OE setup has computer controlled advance. At least I am 99% sure of that. My factory distributor was in poor shape so I bought an amazon special for $55. Seems to work fine.
On the distributor, I would snag a standard HEI that has vacuum advance as the OE setup has computer controlled advance. At least I am 99% sure of that. My factory distributor was in poor shape so I bought an amazon special for $55. Seems to work fine.
