1984 Bronco build thread

[Gary Lewis]

I wish I had a vacuum gage in the cab so I could record that too. then again, I need at least some attention to look at the road with.

I swapped the power valve and went on another spin.

part throttle is still really lean in 3rd and 4rth. past 1/2 throttle both richen up considerably to 14.5 - 16 in 3rd and 15 - 16.5 in 4rth. right when you hit 4rth, if you put the pedal on the floor on level ground you get 18 for a second and then it richens up.

part throttle cruising in 4rth may be fairly lean, like 16.5 - 17. im still running 93. Im tempted to take it on the break in drive.

it fell flat on its face once rolling out of second. Im not sure if Ive lost my touch with a clutch or if the pumpshot isnt doing what I think.

it feels a lot like it did before with one major caveat - I was pushing it hard up hill in 3rd to see what the AFR would read and I didnt notice that I was rolling nearly 4000 rpm! I dont know if it would have free spun that fast before. on the bottom it feels sorta like I remember, on the top it is going to have a lot more breathing room. not to mention that its lean and the ring seat may improve some.

at this point Im inclined to wonder if Im not a little lean on jets, and if I might not need "more power valve". I dont know if those are still made in multiple spring tensions.

You can put the vacuum gauge on the cowl, zip-tied to the windshield wiper. But, having changed the power valve and seeing that it is a lot less lean when you get past 1/2 throttle then you've made progress.

I'd jump 2 or 3 jet sizes before going much farther. You are a lot better off to be too rich instead of too lean. And once you get it broken in you can change the jets again if you are then too rich.

[StraightSix]

You can put the vacuum gauge on the cowl, zip-tied to the windshield wiper. But, having changed the power valve and seeing that it is a lot less lean when you get past 1/2 throttle then you've made progress.

I'd jump 2 or 3 jet sizes before going much farther. You are a lot better off to be too rich instead of too lean. And once you get it broken in you can change the jets again if you are then too rich.

I took my ring break in drive. over the course of the 50 miles the engine seemed to behave in a more predictable way for AFR and just in general.

at this point - Id say that AFR is non issue in 2nd (except lean out when starting from a stop, Ill play with the pump shot). in 3rd and 4rth, WOT always results in an AFR of 14 eventually but it may take a while to get there depending on load and speed. in 3rd its very easy to manage the pedal such that afr never goes beyond 16 even on a decent grade and accelerating. in 4rth a little bit of attention and a gradual sweep from half throttle to full throttle always keeps afr below 16.5 or so. stomping the pedal to the floor in 4rth will result in a lean out to 17.5.

generally, keeping the afr below 16 requires using more throttle than Im used to. I typically drive sluggishly with at 1/4 throttle or less taking half a mile to come up to speed.. (I know I know, the worst kind of person to get behind). keeping AFR happy in this thing seems to require gradual strokes of the accelerator pedal (say 2 - 3 seconds to get from half to full), but you need to be using that gas pedal if you want to accelerate. it will lean out otherwise.

I thought I had 47 jets, but they are actually 52s. Ill need to buy jets as I dont have anything larger than a 50. Does anybody have suggestions on what size (s)? shipping costs more than jets, Id rather buy half a dozen sizes and pay postage once.

other than that, I guess its time for oil changes in the engine and both gear boxes. Ill recheck my valves. is there anything else to look into at this point? too early to run a compression check?

it felt really great to have it out on the road for the first time since July.

[mat in tn]

I took my ring break in drive. over the course of the 50 miles the engine seemed to behave in a more predictable way for AFR and just in general.

at this point - Id say that AFR is non issue in 2nd (except lean out when starting from a stop, Ill play with the pump shot). in 3rd and 4rth, WOT always results in an AFR of 14 eventually but it may take a while to get there depending on load and speed. in 3rd its very easy to manage the pedal such that afr never goes beyond 16 even on a decent grade and accelerating. in 4rth a little bit of attention and a gradual sweep from half throttle to full throttle always keeps afr below 16.5 or so. stomping the pedal to the floor in 4rth will result in a lean out to 17.5.

generally, keeping the afr below 16 requires using more throttle than Im used to. I typically drive sluggishly with at 1/4 throttle or less taking half a mile to come up to speed.. (I know I know, the worst kind of person to get behind). keeping AFR happy in this thing seems to require gradual strokes of the accelerator pedal (say 2 - 3 seconds to get from half to full), but you need to be using that gas pedal if you want to accelerate. it will lean out otherwise.

I thought I had 47 jets, but they are actually 52s. Ill need to buy jets as I dont have anything larger than a 50. Does anybody have suggestions on what size (s)? shipping costs more than jets, Id rather buy half a dozen sizes and pay postage once.

other than that, I guess its time for oil changes in the engine and both gear boxes. Ill recheck my valves. is there anything else to look into at this point? too early to run a compression check?

it felt really great to have it out on the road for the first time since July.

I'm reading along grinding my teeth. I must keep telling myself "It's not a Holley"! I know my limits, but it really seems to be a lean carburetor. I want a 2150 guy to chime in so I can learn too.

[StraightSix]

I'm reading along grinding my teeth. I must keep telling myself "It's not a Holley"! I know my limits, but it really seems to be a lean carburetor. I want a 2150 guy to chime in so I can learn too.

Im a tad nervous too, but I never heard or felt any pinging. All of this was done with 93 in a low compression engine. It wouldnt surprise me much to hear this is exactly what ford wanted that carb to do. I certainly intend to get it running about 2 points richer across the board.

[StraightSix]

Im a tad nervous too, but I never heard or felt any pinging. All of this was done with 93 in a low compression engine. It wouldnt surprise me much to hear this is exactly what ford wanted that carb to do. I certainly intend to get it running about 2 points richer across the board.

Jets in every other size up to 60 are ordered.

[Gary Lewis]

Jets in every other size up to 60 are ordered.

Good plan, Stan. Go up 3 or 4 sizes. It is easy enough to swap jets on a 2150.

[FuzzFace2]

I'm reading along grinding my teeth. I must keep telling myself "It's not a Holley"! I know my limits, but it really seems to be a lean carburetor. I want a 2150 guy to chime in so I can learn too.

When I started seeing the AFR readings I had to go looking to see what carb he was running.

I wished my Carter v1 ran that lean and I had to fatten it up, its just the other way around

If I ease into the throttle I can get into the mid 14's and have seen 15's but most of the time its in the 13's at cruise. WOT goes really rich.

I really need to open my carb again give it a look over and lean it out now that I have the pinging under control.

On the jets you ordered them for that 2150 carb and not a Holley I hope.

I have seen it posted the thread pitch is different and the numbers dont go by the same number system.

I am following good luck

Dave ----

[StraightSix]

I'm reading along grinding my teeth. I must keep telling myself "It's not a Holley"! I know my limits, but it really seems to be a lean carburetor. I want a 2150 guy to chime in so I can learn too.

When I started seeing the AFR readings I had to go looking to see what carb he was running.

I wished my Carter v1 ran that lean and I had to fatten it up, its just the other way around

If I ease into the throttle I can get into the mid 14's and have seen 15's but most of the time its in the 13's at cruise. WOT goes really rich.

I really need to open my carb again give it a look over and lean it out now that I have the pinging under control.

On the jets you ordered them for that 2150 carb and not a Holley I hope.

I have seen it posted the thread pitch is different and the numbers dont go by the same number system.

I am following good luck

Dave ----

Thanks Dave!

Lots of progress. with 56 jets Drivability is great, cruise and round town are 14-15 afr, wot is 12.5, 55 mph flat ground cruising is about 14.3. It does bog slightly and go to 16.5-17 momentarily at WOT in 4rth gear, I think I need a different power valve. Im working on getting a temporary (r maybe permanent) vacuum gauge set up. This should allow me to make a good guess at what size power valve I need.

for anyone with a carbureted engine - I cant recommend an AFR gage enough. It will atleast double your depth of understanding of how your engine operates and it can also save you from some serious trouble.

other than that, things are pretty grand. I have a slight leak from the front output of my transfer case and Ill probably just pull the case down to fix that. but its a slow leak, I dont feel concerned about continuing to drive it as long as Im keeping an eye on it. Its at least road worthy enough to drive around town. Ill try to get you guys a much needed video tour coming up soon.

maybe I can finally fix that snapper..

[FuzzFace2]

Thanks Dave!

Lots of progress. with 56 jets Drivability is great, cruise and round town are 14-15 afr, wot is 12.5, 55 mph flat ground cruising is about 14.3. It does bog slightly and go to 16.5-17 momentarily at WOT in 4rth gear, I think I need a different power valve. Im working on getting a temporary (r maybe permanent) vacuum gauge set up. This should allow me to make a good guess at what size power valve I need.

for anyone with a carbureted engine - I cant recommend an AFR gage enough. It will atleast double your depth of understanding of how your engine operates and it can also save you from some serious trouble.

other than that, things are pretty grand. I have a slight leak from the front output of my transfer case and Ill probably just pull the case down to fix that. but its a slow leak, I dont feel concerned about continuing to drive it as long as Im keeping an eye on it. Its at least road worthy enough to drive around town. Ill try to get you guys a much needed video tour coming up soon.

maybe I can finally fix that snapper..

Good to hear you are getting it dialed in.

I agree on the AFR gauge.

Now that I have my timing curve good I can start on the carb and leaning it out and hope the MPG comes up.

Dave ----

[Gary Lewis]

Thanks Dave!

Lots of progress. with 56 jets Drivability is great, cruise and round town are 14-15 afr, wot is 12.5, 55 mph flat ground cruising is about 14.3. It does bog slightly and go to 16.5-17 momentarily at WOT in 4rth gear, I think I need a different power valve. Im working on getting a temporary (r maybe permanent) vacuum gauge set up. This should allow me to make a good guess at what size power valve I need.

for anyone with a carbureted engine - I cant recommend an AFR gage enough. It will atleast double your depth of understanding of how your engine operates and it can also save you from some serious trouble.

other than that, things are pretty grand. I have a slight leak from the front output of my transfer case and Ill probably just pull the case down to fix that. but its a slow leak, I dont feel concerned about continuing to drive it as long as Im keeping an eye on it. Its at least road worthy enough to drive around town. Ill try to get you guys a much needed video tour coming up soon.

maybe I can finally fix that snapper..

Yes, good that you are getting it dialed in. 14.3 is spot-on, and 14 - 15 will work well. But that leaning out at WOT might be your accelerator pump rather than the power valve. The accelerator pump is to cover up the hole in the fuel delivery that occurs when you rapidly open the throttle as fuel is heavier than air and therefore can't move as quickly. It is a one-shot thing, one and done. But the power valve works until you lift the throttle.

So if the leanness is transient then I'd bet it is the accelerator pump that's the problem.