Lost and cornfused

[Hstrymkrs]

Well, I was WRONG! I looked up Davis Unified Ignition, which is DUI, and most of the distributors I saw were "HEI" style, meaning large and including an internal coil. However, they do make DS-II distributors, coils, ignition wires, etc. So, to be more accurate, "DUI" is a brand of ignition components, including but not limited to HEI-style distributors.

My confusion came from a discussion with Tim Meyer, who was originally going to have DUI populate a distributor housing he manufactured. This was going to include the HEI ignition module, but not the coil, in the distributor, so it was the same size as and looked like a Ford distributor. And, it required the outboard coil, like the DS system, just not the DS module.

DUI didn't get the job done in a timely fashion, and he wound up making them with someone else. He calls them Track Boss RTR, meaning Ready To Run, and says they require 3 wires: "1-hot, 1-ground, 1-negative side of coil. External ignition module not needed." In other words, you don't need to find a DS-II module, wiring harness, and distributor. Just put this dizzy in and connect it to the existing power wire, ground, and the coil.

Tim doesn't, yet, have one for the 300 six, but asked for a pic of a dizzy for the 300 and would consider making them. I've not gotten him the pic, but do y'all think there would be an interest?

I know these are stock pictures, but they all show the vacuum hookup. There is not vacuum advance on my engine as it uses the ICM and the PCM to electronically/mechanically control the advance. This is where I get confused. The Haynes manual states the the TFI-IV is very similar in function to the DS-III. However, I can't find what seems to be an affordable and straight forward option. Maybe I am thinking incorrectly and maybe I am looking for a pink unicorn. What I want doesn't exist?

[ArdWrknTrk]

I know these are stock pictures, but they all show the vacuum hookup. There is not vacuum advance on my engine as it uses the ICM and the PCM to electronically/mechanically control the advance. This is where I get confused. The Haynes manual states the the TFI-IV is very similar in function to the DS-III. However, I can't find what seems to be an affordable and straight forward option. Maybe I am thinking incorrectly and maybe I am looking for a pink unicorn. What I want doesn't exist?

What you want exists.

I'm sorry to have posted a link to the other Ford I-6 series. It's a bit hard to navigate between pages and links on my phone in the reply window.

You need a distributor for a 2.9 or 4.9L engine aka 240 or 300 I-6

Look on Amazon or eBay. They're out there.

You will NEED to use vacuum advance because without a computer to plot the curve (DSII -or- HEI) you are relying on centrifugal springs and that canister to pull the backing plate around.

The vacuum tells the distributor something about engine load and throttle position.

A locked out distributor is good for wfo race conditions only.

[85lebaront2]

I know these are stock pictures, but they all show the vacuum hookup. There is not vacuum advance on my engine as it uses the ICM and the PCM to electronically/mechanically control the advance. This is where I get confused. The Haynes manual states the the TFI-IV is very similar in function to the DS-III. However, I can't find what seems to be an affordable and straight forward option. Maybe I am thinking incorrectly and maybe I am looking for a pink unicorn. What I want doesn't exist?

Ok, first, you obviously have a feedback carburetor system. If you want to make changes it is all or nothing. Any changes you make to the ignition system can screw up the mixture control as it is and integrated system. The reason Jim can't find anything for your application, is these fine Chinese systems are made for non-computer controlled engines.

As far as DS-II, all the wiring is already on your truck, 1985-86 models were built to be able to use multiple systems with minimal changes. If you look at the 1985 and 1986 EVTMs you will notice some strange wiring on the ignition systems. The TFI system does not need or use a ballast resistor, but the DS-II does. Ford built the front harness so whatever system was needed for the engine/weight class and emission requirements would be plug and play. A junkyard DS-II system for a 4.9L will drop in, but your still need to change the carburetor to get everything to play well together.

[ArdWrknTrk]

Ok, first, you obviously have a feedback carburetor system. If you want to make changes it is all or nothing. Any changes you make to the ignition system can screw up the mixture control as it is and integrated system. The reason Jim can't find anything for your application, is these fine Chinese systems are made for non-computer controlled engines.

As far as DS-II, all the wiring is already on your truck, 1985-86 models were built to be able to use multiple systems with minimal changes. If you look at the 1985 and 1986 EVTMs you will notice some strange wiring on the ignition systems. The TFI system does not need or use a ballast resistor, but the DS-II does. Ford built the front harness so whatever system was needed for the engine/weight class and emission requirements would be plug and play. A junkyard DS-II system for a 4.9L will drop in, but your still need to change the carburetor to get everything to play well together.

Bill,

I can find them.

Linking from the Amazon or eBay app on my phone needs some kind of workaround.

Because this forum is not privy to my history in those apps. (as it should be)

I personally think Williams 500cfm carb is way too big for for the application.

Largest I've gone on a 300 is the somewhat obscure 435 cfm 4160, and that was on a decked, cammed and bored 300 with an Offy intake and EFI manifolds.

It was ok but still seemed a bit soft even with a lot of tuning of secondary springs.

You would know better than me

[ArdWrknTrk]

Bill,

I can find them.

Linking from the Amazon or eBay app on my phone needs some kind of workaround.

Because this forum is not privy to my history in those apps. (as it should be)

I personally think Williams 500cfm carb is way too big for for the application.

Largest I've gone on a 300 is the somewhat obscure 435 cfm 4160, and that was on a decked, cammed and bored 300 with an Offy intake and EFI manifolds.

It was ok but still seemed a bit soft even with a lot of tuning of secondary springs.

You would know better than me

I'm going to try and log out of eBay and Amazon and then pull up the items in my browser.

Let's see if this works....

https://www.ebay.com/itm/A-TEAM-HEI-DISTRIBUTOR-FORD-240-and-300-ENGINES-BLUE-CAP-F100-F150-F250-E150-/262671083747?redirect=mobile

https://www.ebay.com/i/191838774982?chn=ps&ul_ref=https%253A%252F%252Frover.ebay.com%252Frover%252F1%252F711-117182-37290-0%252F2%253Fmpre%253Dhttps%25253A%25252F%25252Fwww.ebay.com%25252Fi%25252F191838774982%25253Fchn%25253Dps%2526itemid%253D191838774982%2526targetid%253D593772395653%2526device%253Dt%2526adtype%253Dpla%2526googleloc%253D9003452%2526poi%253D%2526campaignid%253D1661457327%2526adgroupid%253D63612800546%2526rlsatarget%253Dpla-593772395653%2526abcId%253D1140466%2526merchantid%253D8298174%2526gclid%253DCj0KCQiA68bhBRCKARIsABYUGicvIJb-vkq-LmzVlr3a6PSDHEb_FzxzVtSLtSloUn4_vkReVru1r9oaAm95EALw_wcB%2526srcrot%253D711-117182-37290-0%2526rvr_id%253D1810012423829%2526rvr_ts%253D25cd3e891680ac3ca59669c7fff09bd3

https://www.amazon.com/HEI-DISTRIBUTOR-FORD-ENGINES-BLUE/dp/B01CH23N2U

https://www.amazon.com/Team-Performance-Distributor-Compatible-Instillation/dp/B073WM92CQ/ref=pd_cp_263_1?pd_rd_w=WUrWt&pf_rd_p=ef4dc990-a9ca-4945-ae0b-f8d549198ed6&pf_rd_r=FMW9AMPBPEAHP19BEY32&pd_rd_r=cc4efda9-1216-11e9-aa93-791c7bad081c&pd_rd_wg=OjHl6&pd_rd_i=B073WM92CQ&psc=1&refRID=FMW9AMPBPEAHP19BEY32

[85lebaront2]

I'm going to try and log out of eBay and Amazon and then pull up the items in my browser.

Let's see if this works....

https://www.ebay.com/itm/A-TEAM-HEI-DISTRIBUTOR-FORD-240-and-300-ENGINES-BLUE-CAP-F100-F150-F250-E150-/262671083747?redirect=mobile

https://www.ebay.com/i/191838774982?chn=ps&ul_ref=https%253A%252F%252Frover.ebay.com%252Frover%252F1%252F711-117182-37290-0%252F2%253Fmpre%253Dhttps%25253A%25252F%25252Fwww.ebay.com%25252Fi%25252F191838774982%25253Fchn%25253Dps%2526itemid%253D191838774982%2526targetid%253D593772395653%2526device%253Dt%2526adtype%253Dpla%2526googleloc%253D9003452%2526poi%253D%2526campaignid%253D1661457327%2526adgroupid%253D63612800546%2526rlsatarget%253Dpla-593772395653%2526abcId%253D1140466%2526merchantid%253D8298174%2526gclid%253DCj0KCQiA68bhBRCKARIsABYUGicvIJb-vkq-LmzVlr3a6PSDHEb_FzxzVtSLtSloUn4_vkReVru1r9oaAm95EALw_wcB%2526srcrot%253D711-117182-37290-0%2526rvr_id%253D1810012423829%2526rvr_ts%253D25cd3e891680ac3ca59669c7fff09bd3

https://www.amazon.com/HEI-DISTRIBUTOR-FORD-ENGINES-BLUE/dp/B01CH23N2U

https://www.amazon.com/Team-Performance-Distributor-Compatible-Instillation/dp/B073WM92CQ/ref=pd_cp_263_1?pd_rd_w=WUrWt&pf_rd_p=ef4dc990-a9ca-4945-ae0b-f8d549198ed6&pf_rd_r=FMW9AMPBPEAHP19BEY32&pd_rd_r=cc4efda9-1216-11e9-aa93-791c7bad081c&pd_rd_wg=OjHl6&pd_rd_i=B073WM92CQ&psc=1&refRID=FMW9AMPBPEAHP19BEY32

Did great sir, finest Chinese ignition systems! I personally would buy a junkyard DS-II system and plug it in.

[ArdWrknTrk]

Did great sir, finest Chinese ignition systems! I personally would buy a junkyard DS-II system and plug it in.

Yup, but he says he wants a one wire dizzy at an affordable price, and that there are no junkyards to pick from.

So I link what he asked for.

If it gets his Bronco back on the road or trails it's all good.

[Gary Lewis]

This is one of the problems that I am running into. They show the distributor, but then say it doesn't fit the application.

I am fairly green at this, so forgive me if I use a general term that might need more clarification. I have been turning wrenches for many years, and I worked on generators in the military. I understand how engines work, and I can most always get them running. However, I have much to learn on the specifics and the fine tuning of the things.

By increased performance, I merely imply that I want it to run efficiently and smooth primarily, and if it gives me a little extra horses that is great. I haven't done anything to the engine other than send it off to the machine shop to have it gone through and reassembled. It is bored 0.040 over and we put a cam that claims to help increase torque/horsepower. I do not expect it to be a high RPM engine as my main goal is torque for off-road enjoyment and cruising for the joy of driving an older full size Bronco.

While I am not against the DS-II, it just seemed easier to put a DUI/HEI and move on. Whenvever I would read about them, the thread would always turn into a DS-II thread and never really go anywhere else. Most of the DUI/HEI are for the V8 and the smaller inline 6s. I was initially confused as the TFI-IV seemed to be a hybrid/transition from the carburetor to the EFI systems. I am not sure what it would take to convert to a fully EFI system, but I would think that would add cost that I can't afford. The engine is ready to go as soon as I reassemble the all the accouterments, so I am not certain that changing in mid build is a good idea for me at this moment. Additionally, I am deleting the EGR/Smog pump only because it adds extra cost to bringing this thing back up and running. My smog pump is seized up wont even make a good boat anchor.

Honestly, I am just trying to do a modest rebuild and hope to get the most out of the engine, i.e., reliability and strength.

This truck has great memories for me, and I just want to get it back up and running well without needing a second mortgage. The junk yards around here just plain suck. They want too much money for their stuff and the closest pick-n-pull is 2 hours away. If the DS-II is great and reliable then I can go that way, but the threads make is seem so complicated. I have a bad distributor and I need a new one. I don't want to cut corners, I just don't have the money to get everything now. I would honestly be happy with it being stock again. It just doesn't seem practical...not that putting any money into this old of a vehicle is practical in any way.

I appreciate all the replies and attempts to help. I will reread them and try to clarify my objectives more.

You all are a great help.

You ask what I want to do with my Bronco? Here you go!

William

Let's see if this works:

It did. You have to get the "embed" code.

[85lebaront2]

Yup, but he says he wants a one wire dizzy at an affordable price, and that there are no junkyards to pick from.

So I link what he asked for.

If it gets his Bronco back on the road or trails it's all good.

I hope it works for him. Just don't ask me for help!

[Hstrymkrs]

I hope it works for him. Just don't ask me for help!

Thanks again to you all. I am not trying to be difficult, just trying to learn. I will look at these links and mull over the responses in hopes of coming to a better understanding of how it all works and changes over.

Thanks again.

William