franklin2
Well-Known Member
- Joined
- Dec 24, 2019
- Messages
- 3,425
- Reaction score
- 1,758
- Points
- 113
- Location
- Virginia
- Vehicle Year
- 1984
- Make / Model
- Bronco II
- Transmission
- Manual
On my 1984 2.8, my original computer carb did have a full electric choke from the factory. It had a relay module that was controlled by the computer that sent it a full 12v for operation.The Holley electric choke needs a 12v source, the hot wire on the wiper motor is easy to tap into. The original 2150 had a hot air tube running to the exhaust manifold and used stator voltage from the alternator to speed up choke opening, I think about 7 volts.
But somewhere along the way, someone had re-wired it to the alternator s terminal, the relay module had gone bad and it's probably one of those parts you can't get anymore. The choke seemed to work ok.
I then changed it all out and did the duraspark II swap. I ran the original carb for a few months, and then I bought one of those chinese knock-offs off Amazon and am running it. I swapped the electric choke from the old carb to the new, and am still running it off the stator of the alternator. While it probably is slower to open up, it still overall seems to work ok.
On the carb, I looked and looked, the China carbs are not made in the 1.08 venturi. The smallest I could find was a 1.14 venturi. I left the stock jets in it as it came. What surprised me is with the old computer carb and the duraspark distributor, the best I could get was 15mpg. After the carb swap, my fuel mileage jumped to 20mpg. The carb was only about $99, so it's quickly going to pay for itself in fuel savings.
The other guys are correct. I dont know how large your holley carb is, but even only jumping one venturi size up, from the original 1.08 to the 1.14, I can tell it's just slightly soggy on the bottom rpm range. In the upper rpms where the 2.8 stays most of the time, you will not notice any difference. But nailing the throttle while being in a higher gear, it's not as responsive as it was with the smaller carb. Changing jets is not going to fix it if that ends up being a problem.