2.3L ('83-'97) 1983 Down on Power

[bilbo]

I drove it around a bit today and the response off idle is much much better than the carter was. It revs very quickly. But then it falls flat on its face, not much power at all. It’s got to be a jetting thing or a flaw with the carb. Looks like I will need to do some plug chops or something.

 

[ExploreNW]

Got it all together and running today. It took some fiddling with the mixture screw to get idle right but it seems to idle nice now. I’ll still have to set the high idle and stuff up. I had to modify the throttle cable bracket and plumb coolant to the choke but other than that the 5200 was plug and play using an adapter for Jeeps with Carter 1bbl carbs. The heater tube on my water outlet is buggered up and sprayed coolant everywhere on my test drive so now I have to wait for the RTV to set before I mess with it more. I have a cheap air cleaner I found on eBay for now until I can fab something nicer up. If my photos don’t work due to size I’ll try and get them up Monday when I have a pc again. View attachment 37871View attachment 37872

That 5200 looks great on your 2.3! Glad you got it up and running too. Your throttle cable bracket work looks a lot better than mine, I just took a peanut wheel to it. And I'll be damned if I could've gotten that manifold-heater tube to hold the first time... or the third... haven't blown the hose off and dumped all my coolant in a while so I guess the tube metal is okay to cinch pipe clamps on as tight as one can.

As for the runability issue, since you got the idle and low-end nailed we now need to tweak part-throttle cruise (PTC) and WOT fuel mixtures. Grab a vac gauge and hook it to manifold vacuum. Run a spare bit of vac line through a hole in the firewall so you can read the gauge while driving around. Can be any old gauge in the shop, even a spare boost gauge with vac markings will work. Throw a note pad in the truck to take note of how much vac you have cruising on the highway, accelerating mild & hard, cruising on a city street, and how much vac you have when you come to a stop off the freeway. Then swap over to your spark port and monitor when its getting vacuum, it might be beneficial to use a different port for spark if you see anything weird here.

On your way home, floor the sucker as much as possible. Get home, shut it down, read plugs as immediately after your WOT run as you can - how do they look? Pop the air cover... Is the choke still engaged?

Since you're dealing with a 2bbl progressive carb that seems to do nicely until power is needed, the secondary (bigger) barrel is suspect #1. This should be closed at part-throttle cruise and open under acceleration and WOT. You should see a steady drop in vac as it opens. What size jets are on your carb? When is your secondary set to open? How is your accelerator pump set?

 

[bilbo]

I started a new thread just on the carb swap, it's a couple down from this one. The jetting info is in there. This weekend I should be able to try a plug chop, but I'm not sure how good they are any more. I've done some on sleds and stuff and different components in today's fuels can leave deceitful deposits. Our neighbor across the streets is a retired Chrysler mechanic and worked through the smog era, that's what he tells me anyway.

I have an AFR meter on the way to hopefully help with tuning. The fitting is already there for the MCU stuff, just need to stuff the wideband sensor in and that should hopefully give me a no-BS picture of what's going on.