1985 2.8 Carb Adjustments

[Uncle Gump]

You're really making me think now... The carbs I mostly dealt with were metric. So I believe you would have to convert your 1.08 to mm.

It was the formula that was written in the Dellorto handbook. Let me see if I can find it... haven't seen it in awhile.

 

[Uncle Gump]

I just looked and it wasn't where I thought it was.... then it hit me. That calculation is for using dual carbs on a VW. So one venturi/main jet would be supplying a single cylinder.

So lets forget that calculation. Maybe you can do a bit of googling and find some info for your application.

 

[ford4wd08]

I just looked and it wasn't where I thought it was.... then it hit me. That calculation is for using dual carbs on a VW. So one venturi/main jet would be supplying a single cylinder.

So lets forget that calculation. Maybe you can do a bit of googling and find some info for your application.

I've been working on the googling for a little bit now, not finding much.

 

[franklin2]

If you want to stick your old feedback carb on it, it will work. I have been running mine for a year now with all the wires gone. It idles and starts extremely well, and runs out well also. Does 80 mph easy on the interstate with no hiccups at all.

I did notice I am getting what think is crummy fuel mileage. I checked it the other day, I am getting 16.5 mpg. My other little ranger with the 2.9 fuel injection would get 20 mpg on a summer day, less during the winter. Of course I can't leave well enough alone, like I said the feedback carb runs great. But I was thinking about experimenting with the feedback solenoid and see if I can get a little bit better mileage out of it.

I am figuring I can basically change the jet size by pulsing the solenoid more or less. Thinking about just getting a momentary switch to pulse it by hand as I drive down the road to see what happens. If it has a large affect, I might get a repeat timer that I can set to dial it in.

 

[ford4wd08]

If you want to stick your old feedback carb on it, it will work. I have been running mine for a year now with all the wires gone. It idles and starts extremely well, and runs out well also. Does 80 mph easy on the interstate with no hiccups at all.

I did notice I am getting what think is crummy fuel mileage. I checked it the other day, I am getting 16.5 mpg. My other little ranger with the 2.9 fuel injection would get 20 mpg on a summer day, less during the winter. Of course I can't leave well enough alone, like I said the feedback carb runs great. But I was thinking about experimenting with the feedback solenoid and see if I can get a little bit better mileage out of it.

I am figuring I can basically change the jet size by pulsing the solenoid more or less. Thinking about just getting a momentary switch to pulse it by hand as I drive down the road to see what happens. If it has a large affect, I might get a repeat timer that I can set to dial it in.

I'm afraid my feedback carb is too far gone.... LOL it has been robbed of a few parts to rebuild the one I have on it now. I mean it could be used, but I had a lot of trouble out of it.

This B2 seems to be running well. I am just curious if it running as well as it can be. I would say any carb issue is more about me learning on how to work on them vs them being really an issue.

The reason I am on jets now is just to confirm then. It can change from where you live and drive and all etc.

Also, I do have a slight shudder at 45 mph when I am pulling a hill or something. It could be something else, but the shudder goes away if I give the engine more throttle, so I don't believe it is transmission or road speed related. I think it is more engine related.

I don't expect this thing to be a speed demon, but I would think it could pull a hill in OD at 60 mph.... maybe I'm asking too much?

 

[ford4wd08]

I did find a 2150 on ebay that was for a pinto that had size 47 jets in it.

I need to confirm mine, I might look tonight when I get home.

 

[19Walt93]

If it has stock 70's jets you might benefit by increasing one or 2 jet sizes, try 2 sizes first and if improves drop down one number and see how it works. The vacuum advance hose should be attached to the spark port on the right of the carb so it advances under acceleration, some 70's stuff ran intake manifold vacuum to the advance which would often cause a steady speed surge and a loss of power under load. If you used a 70's distributor too, it's likely you can make a big improvement by either changing springs or bending the tabs below the base plate. The factory advance wasn't fully in until 4500 on my 77 Mustang, it's all in at 2800 now and runs 13.8 in the quarter.

 

[ford4wd08]

If it has stock 70's jets you might benefit by increasing one or 2 jet sizes, try 2 sizes first and if improves drop down one number and see how it works. The vacuum advance hose should be attached to the spark port on the right of the carb so it advances under acceleration, some 70's stuff ran intake manifold vacuum to the advance which would often cause a steady speed surge and a loss of power under load. If you used a 70's distributor too, it's likely you can make a big improvement by either changing springs or bending the tabs below the base plate. The factory advance wasn't fully in until 4500 on my 77 Mustang, it's all in at 2800 now and runs 13.8 in the quarter.

Thanks for the good advice as usual.

It is all 70's equipment. The distributor is for a 78 Mustang II with the 2.8. All I know about the carb is that it is from a Pinto and is 1.8 Venturi.

I have the jets from my 2150A carb still. I'll check and see what they are and can swap them in pretty easily. That might be my next step.

What is the total timing that is all in by 2800? I have the vacuum advance hooked up to ported vacuum. I checked it with a vacuum gage. The port is on the right side front of the carb by the throttle linkage.

I feel like I need to do some more tuning to get the best I can out of this rig.

 

[ford4wd08]

Just an update. I tightened the pull off about a half a turn at each cold start until it stayed running after the first try. Seems to be ok now.

I'm going to play with the distributor and see if I can get all the timing in like @19Walt93 suggested.

I feel like this rig has more. I'm going to find it lol.

 

[Uncle Gump]

Good... I'm glad you're making progress.

As for the "more"... be sure to keep your expectations within the limits of what you have to deal with.

I would suggest baby steps and let fuel economy be your guide.

 

[19Walt93]

Just an update. I tightened the pull off about a half a turn at each cold start until it stayed running after the first try. Seems to be ok now.

I'm going to play with the distributor and see if I can get all the timing in like @19Walt93 suggested.

I feel like this rig has more. I'm going to find it lol.

I'm glad you're making progress. It's worth checking the valve adjustment, too. 2.8's have solid lifters and if the lash is even a little too loose it will hurt power.

 

[ford4wd08]

Good... I'm glad you're making progress.

As for the "more"... be sure to keep your expectations within the limits of what you have to deal with.

I would suggest baby steps and let fuel economy be your guide.

I understand this is still a 2.8 lol

I just think it has a little more on it. I believe it should be able to pull hills better.

 

[ford4wd08]

I'm glad you're making progress. It's worth checking the valve adjustment, too. 2.8's have solid lifters and if the lash is even a little too loose it will hurt power.

That is on my short list as well.

I've only got about 63,000 miles on this motor, I'm unsure how frequently you have to check solid lifters for lash?

I need to replace the valve cover gaskets anyhow, I've already got the set to do it. Just need to pull it in the garage and do it.

I've got the feeler gages needed as well.

 

[19Walt93]

That is on my short list as well.

I've only got about 63,000 miles on this motor, I'm unsure how frequently you have to check solid lifters for lash?

I need to replace the valve cover gaskets anyhow, I've already got the set to do it. Just need to pull it in the garage and do it.

I've got the feeler gages needed as well.

The book used to say every 15,000 ,miles. I did my V6 Mustang II at 10k and it made a huge difference. Lash too loose acts like the cam got smaller.

 

[ford4wd08]

The book used to say every 15,000 ,miles. I did my V6 Mustang II at 10k and it made a huge difference. Lash too loose acts like the cam got smaller.

Sounds like I've got some work to do!

I have decided today I'm going to buy a new timing light that has RPMs readout built into it. That should be a useful tool for all of this work and help me get everything set up right. I've reach my limits on my harbor freight cheapy.

I'm going to see the stock size jet in my 2150A and probably get a few more sets ordered just so I can have them to trial and error with.