Thank you everybody! just got the truck running. i just needed to swap in the complete DS2 system and it works. once it cools down a little im gonna go get everything buttoned up and take it for a test drive

 

Glad to hear it, Randy.

The Duraspark wire harness I got came with the factory plug for the factory tachometer as well. When I did mine, I cut out the ENTIRE computer and gang plug of wires that went to the firewall and the Duraspark wire harness I got from the junkyard plugged right in neatly without any splicing at all. I also grabbed the smooth rubber grommet plug from the donor junkyard truck to replace the grommet with the big hole cut in it for the SIXTY computer wires, and you would never know my truck once had the EEC-IV/ TFI mess in it.

Going with the Duraspark ignition will save you a lot of headache, and it is a good, reliable system. Good job!

 

thanks, i need to find one of those smooth plugs. i still have a big hole.

i took my test drive and it was ok for a little while but then the RPMs started jumping from 500 to 1000.

do i have to get rid of the EGR stuff along with the computer?

 

Are you still running the feedback carburetor? If you are, that would explain why your RPMs are jumping. Is your vacuum advance on your distributor hooked up to PORTED vacuum on the carburetor?

NO, you do not have to get rid of the EGR. The EGR should be controlled by a vaccum check valve. It is only supposed to open at cruising speeds, so make sure that it is still hooked up to vacuum.

If you do decide to get rid of the EGR like I did, you can do that but you are going to have to make a few other modifications as well. First, you will need to get another intake manifold that does not have the EGR provision. Then you will need to re-curve your distributor and perhaps re-tune your carburetor to deal with the missing EGR valve, or better yet run a non-emissions carburetor.

 

no i changed the carb along with everything else. it looks like my old carb but the places where the sensors were attached to the old carb are blocked on this one. i bought it off of ebay and it said it was a non computer controlled.

how can i tell if the vacuum port is ported?

thanks, i didnt want to have to try and remove the EGR if i didnt have to.

 

Randy2631
I'm converting to DS2 in a 1986 Ford F-150 with 4.9l engine. I've been concerned that the voltage that I'm reading after plugging the DS2 harness into the old tfi plugs(specifically the tfi plug containing the thick red-yellow from a three way splice with a resistor and a brown -pink bypass) that match the wire on the DS2 side to the coil and water and oil sensor wires.

Have you been running a DS2 coil successfully and supplying it through the plug that gets the thick red-yellow wire? And do you know what voltage you have at the red wire positive pot of your DS2 coil with ignition in run position both with engine off(I got 12v) and engine running(I got 10v)?

 

I use my TFI coil with my DSII dist. and box just fine. The local part store had a simple pigtail assembly to hook it up. Cost about $15.

 

Yea its been working great. I used the older style coil with the horseshoe style connector.

from what i understand the reason for the lower voltage when the engine is running is so that the coil doesn't overheat.

i mounted the coil on the bracket that the old vacuum switches were on.

 

Thanks I'll try to post a link to the thread I started as I got into this tfi conversion to DS2.

https://www.ford-trucks.com/forums/8...ml#post7990532
Both of the responses you sent remove some of the fears I had that are still not completely answered. I mounted the whole DS2 system coil , distributor module and harness and was amazed that everything connected and no wiring to add. Then I checked the voltage coming off of the thick red-yellow wire from the bypass,resistor and fed the coil red-yellow three way spice. This was supply to the positive on DS2 coil. I had read that the feed should be 6-8 volts and got 12v engine off and 10v engine running. That sent up a red flag and I've been hunting a solution evre since. Apparently the 10v hasn't melted your coil so everthing is fine.


The other option that I had thought of was to go back to the tfi coil since I knew it had been running on the red-yellow voltage wire and not worry about the coil voltage being above 6-8v. Then I'm warned that the tfi coil may start another set of problems. Apparently that also has not cause sytem failures since the tfi with DS2 module also has survived.

I guess I should just drive. what's the worst that can happen?

 

Interesting post here. Hoping to revive it. What coil did you end up using?

I was running the tfi coil with my duraspark 2 with no problems. Then I read it could burn out my module so I put on a can type coil. I liked the tfi better but I don't want to fry modules. What ended up working best for you?

 

Some people have had success with running a TFI coil with their Duraspark systems, but I would not recommend that. More people have had problems, like a fried Duraspark II module. But that seems to happen more with the cheaper aftermarket modules. The bottom line is, the Duraspark ignition system was engineered and designed to run with the Duraspark "can" style coil, and that is the one you should use.

 

Makes sense! Thanks Lariat85.

Would a performance type can coil be okay or would it even give any benefit to a stock engine?

 

NO, save your money and spend it someplace else on your truck. A "performance" coil will do absolutely nothing to a stock truck or even a mildly built engine that the original Motorcraft coil can't already do. The Duraspark ignition is a perfectly capable ignition system as it is. Unless you are going to spending a lot of time over 5,000 RPMs or are actively drag racing your pickup truck, you will not gain any benefit using a "performance" ignition. The best thing you can do is to make sure you are running MOTORCRAFT parts, as the cheaper replacement aftermarket parts are notoriously unreliable.

 

I'll try to find the receipt I have for mine so I can post up the part number, bought it at the Ford dealer.

 

Wyowanderer,

I believe the number is: E3DZ-14603-A, for the dash grommett [smooth plug].