Ford TFI question.

All questions about MS2/Microsquirt/Microsquirt module. See also MS2/Extra manuals

Moderators: jsmcortina, muythaibxr

Post Reply
Twistedmetal
Helpful MS/Extra'er
Posts: 85
Joined: Mon Jul 11, 2011 9:43 am
Location: NW Minnesota

Ford TFI question.

Post by Twistedmetal »

The car runs fine, I dont have much to do but tie up loose ends and slay some minor demons. I have a fairly annoying cruise/boost miss that has been plaguing me for awhile and I believe it is ignition related. The car pulls very hard and it is a very soft random miss, I cannot feel it but I can hear it in the exhaust, it does not effect power during cruise but it will at 10+ psi. Spark plugs are gapped at 0.028 and blowout is not a problem. I am using the JS10 ignition mod, not D14.

The question is, what is the difference between using JS10 and D14 for this type of ignition? Also would changing fixed duty to a new set of dwell settings help? What is the benefit of switching to D14 for the Ford TFI?

EDIT: 5/16/17 Scroll down to last post for a better way to control a stock harness TFI vehicle (or self built, just don't use the TFI to fire the coil).
Last edited by Twistedmetal on Wed May 17, 2017 9:00 am, edited 1 time in total.
MS3X v3 w/Ford IAC mod running MS3 1.41
Sig PIP TFI trigger with direct coil control, 60# highZ injectors
91 Ford Mustang, modified 5.0, 70mm turbo @ 11#s
Matt Cramer
Super MS/Extra'er
Posts: 17499
Joined: Thu Apr 16, 2009 8:08 pm

Re: Ford TFI question.

Post by Matt Cramer »

Twistedmetal wrote:The car runs fine, I dont have much to do but tie up loose ends and slay some minor demons. I have a fairly annoying cruise/boost miss that has been plaguing me for awhile and I believe it is ignition related. The car pulls very hard and it is a very soft random miss, I cannot feel it but I can hear it in the exhaust, it does not effect power during cruise but it will at 10+ psi. Spark plugs are gapped at 0.028 and blowout is not a problem. I am using the JS10 ignition mod, not D14.

The question is, what is the difference between using JS10 and D14 for this type of ignition? Also would changing fixed duty to a new set of dwell settings help? What is the benefit of switching to D14 for the Ford TFI?
The two don't have any performance differences.; it just depends on what I/O you need to use for other points.

Most TFI units have the module controlling dwell and the ECU cannot force it to run a different amount of dwell.

If that's a V8, the TFI may not have an easy time lighting off 10 psi of boost!
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Twistedmetal
Helpful MS/Extra'er
Posts: 85
Joined: Mon Jul 11, 2011 9:43 am
Location: NW Minnesota

Re: Ford TFI question.

Post by Twistedmetal »

Good to know. Is there a way to boost output using this configuration without an MSD box for the time being? I am upgrading my v3.0 board to MS3/EXTRA for sequential fuel and spark but not for a few months, I just want to bandaid it for now. Is the MS2 even feeding the TFI the correct signal that it wants to see?
MS3X v3 w/Ford IAC mod running MS3 1.41
Sig PIP TFI trigger with direct coil control, 60# highZ injectors
91 Ford Mustang, modified 5.0, 70mm turbo @ 11#s
Matt Cramer
Super MS/Extra'er
Posts: 17499
Joined: Thu Apr 16, 2009 8:08 pm

Re: Ford TFI question.

Post by Matt Cramer »

The MS2 should be sending it the right signal; just make sure your ignition advance is operating normally.

Easiest way to put an MSD box on the car would be to treat it like it has the stock ECU - the MS won't see the MSD, and the MSD won't see the MS. It may be a band aid, but not all cuts require breaking out the anesthetic and stitches.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
rickb794
Super MS/Extra'er
Posts: 6155
Joined: Sun Dec 21, 2008 10:28 am
Location: Portland OR

Re: Ford TFI question.

Post by rickb794 »

I don't get why one would want multiple devices in a daisy chain in a high performance application.

First you have an MS which is capable of running a coil by itself in applications with 15# boost or more (in wasted spark).

Then you go and trigger the MS with a device at the tail end of mechanical chaos. (the tail wagging the dog)

Then you use a second module that is also capable of running a coil to

trigger a third box, that enjoys a less than favorable failure rate and dubious power gains, to fire the plugs.

All of this nonsense is following the known mechanical deficiencies of a distributor trigger.

Crank trigger the MS and junk the useless bits that only add additional points of failure...
Correctly identify your MS ecu here
Read the Do's and Don'ts to avoid the common pitfalls before starting your install or asking for help
Use only these manuals other manuals may cause brain damage or worse.
Twistedmetal
Helpful MS/Extra'er
Posts: 85
Joined: Mon Jul 11, 2011 9:43 am
Location: NW Minnesota

Re: Ford TFI question.

Post by Twistedmetal »

That is the plan, I DO NOT like bandaiding or daisy chaining but I need more spark. Timing advance is working correctly. So I wont need to hook the MSD box to the MS directly if I buy one for a stock TFI application with the adapter harness it should be fine. The MS is getting crank/cam triggered soon but just not right now.
MS3X v3 w/Ford IAC mod running MS3 1.41
Sig PIP TFI trigger with direct coil control, 60# highZ injectors
91 Ford Mustang, modified 5.0, 70mm turbo @ 11#s
PSIG
Super MS/Extra'er
Posts: 1146
Joined: Sat Jun 12, 2004 12:02 am
Location: Seattle, WA area

Re: Ford TFI question.

Post by PSIG »

Twistedmetal wrote:That is the plan, I DO NOT like bandaiding or daisy chaining but I need more spark.
I disagree. You are saying the factory TFI does not have enough power to fire properly at cruise? You have a miss under power, but also at cruise. Considering stock TFI is good for 15# and 6500 with the tighter gap, I don't think ignition power is your miss issue - especially considering it also misses under light load.

David
-=≡ If it was easy, everyone would do it. ≡=-
Twistedmetal
Helpful MS/Extra'er
Posts: 85
Joined: Mon Jul 11, 2011 9:43 am
Location: NW Minnesota

Re: Ford TFI question.

Post by Twistedmetal »

PSIG wrote:
Twistedmetal wrote:That is the plan, I DO NOT like bandaiding or daisy chaining but I need more spark.
I disagree. You are saying the factory TFI does not have enough power to fire properly at cruise? You have a miss under power, but also at cruise. Considering stock TFI is good for 15# and 6500 with the tighter gap, I don't think ignition power is your miss issue - especially considering it also misses under light load.

David
Actually the cruise miss was faulty plugs (Autolight 3923s), I installed NGK BKR7EIX-11s gapped at 0.029 and the miss is gone. I can feel power loss approaching 11psi but it isnt nearly as bad as it was. The 21 year old TFI module may have have had better days. This motor might just get a wheel sooner.


-Dave.
MS3X v3 w/Ford IAC mod running MS3 1.41
Sig PIP TFI trigger with direct coil control, 60# highZ injectors
91 Ford Mustang, modified 5.0, 70mm turbo @ 11#s
Twistedmetal
Helpful MS/Extra'er
Posts: 85
Joined: Mon Jul 11, 2011 9:43 am
Location: NW Minnesota

Re: Ford TFI question.

Post by Twistedmetal »

Ok, I am resurrecting this old thread, not because I need to but because I want the next guy to stumble across this one day and maybe it helps him or her out. So life got in the way of my car since last I posted, the spark plug thing didnt solve the problem and it still had a miss, then passed 5 years...

I got what I needed done, done. Now back to what I love to do...

So, I rebuilt the motor last month, same block, same combo, same boost. I decided to give the TFI another whack mostly because I just wanted to drive the car, the EDIS was rock solid but I wanted spark cut rev limit and launch control eventually, I just wanted to control the coil more or less. I tossed around the Idea of a number of different options and just settled on using a dizzy for the sake of time. The MS3, COPs and VR are still on the list but I'll do that when I need (want) to.

I put the TFI back in the car, did the DIYautotune TFI input and pullup mod (again, lol) and got the car running. Que the old miss, in the morning you couldnt drive it, they were a no go, afternoons it was fine minus the occasional miss.. Tried 2 more dizzys, 3 other TFIs, miss was still there tach was bouncing like usual. Now the grey TFI will spark on it's own if you pull the SPOUT, it does not need input from the computer, you can effectively lock timing this way if you want, the TFI still send the PIP to the MS2 with the SPOUT unplugged and with the computer unplugged the TFI will still fire spark as long at it has power, it really was a good concept on Ford's part back in the 80s, good thing it's not the 80s anymore. If you unplugged the SPOUT the TFI would make a consistent, hot and clean spark. If the SPOUT was plugged in (MS2 feeding the TFI timing advance information) the spark would be inconsistant, weaker and varied in intensity.

Ok, now I felt I was getting somewhere, the TFI may be getting overloaded or it doesnt like the input or whatever, didnt care, I've been fighting with this for years and I've had it. I cut the pullup resistor leaving the IGBT output as it should be for high current coil control, leave the D1 and D2 resistor and jumper in place for the TFI PIP signal to be read by the MS2, pulled the #2 and #5 wire out of the TFI connector (I'm not cutting a perfectly good harness) and installed a blade in the shape of a horseshoe, jumpered the SPOUT connector (it wasnt behaving with the factory SPOUT plug in it) and changed the ignition settings in TS and started it.

Popped right off, runs like a million bucks, better than it ever did, ever. Took it out for a shake down and left a hundred feet of rubber right on the rev limiter.

If you come across this thread in the future and you have a TFI Mustang or other car/truck/whatever and are having problems or you want to Megasquirt it, DO NOT do the TFI mod, DO WHAT I DID HERE!!! Use the TFI input mod for trigger, DO NOT INSTALL the pullup resistor and use the high current coil control to drive the coil directly right through the stock harness. Save yourself the crap and messing around, you dont have to wreck anything this way and it's not very hard.

Attached is a VERY rough road and boost tune, I basically started over and it's not nearly done BUT if you have a turbo 5.0 you should be able to change injector size and run it, might save you some time. The timing map wont pop your block or gaskets, it's ridiculously conservative and I did that on purpose is case I had a lean spot or something went haywire I wouldn't be taking the wrenches back out, still makes wild power right up to the top

- Dave.

Tags: megasquirt 2 3 v3 v3.0 self assembled board tfi spark miss direct coil control
MS3X v3 w/Ford IAC mod running MS3 1.41
Sig PIP TFI trigger with direct coil control, 60# highZ injectors
91 Ford Mustang, modified 5.0, 70mm turbo @ 11#s
LP1
MS/Extra Newbie
Posts: 1
Joined: Wed Jul 12, 2017 6:39 pm

Ford TFI No advance

Post by LP1 »

Thanks for your post, excellent idea. We bought a Mastercraft ski boat years ago that needed a new engine. Picked up a truck 351W EFI and decided to Megasquirt the boat, MS2 V3, MS extra. Works great but the ignition wouldn't advance and I assumed it was the TFI module so decided to deal with it later. I set a fixed timing optimized for ski conditions, the engine ran like a champ with plenty of power. Decided to upgrade the injectors last year (about 5 years after the initial setup), ran into some fueling issues so decided to fix the ignition while I was at it. Threw parts at it but still no advance. Went through the wiring which was okay and was about to dissect the megasquirt when I found your post. Great idea, cut out the middle man (TFI), and have megasquirt handle the ignition advance. Boat went from a stump puller to rip the arms off your body, you can never have enough power!

As an aside, the boat fuel tank was an easy retrofit for EFI as it already had an extra bung for the return line. The only issue was that you could only use the top have of the tank while maneuvering as the fuel sloshed around with a resulting loss of fuel pressure when it sucked air. The fix is the Holley Hydramat which works as advertised, we can run the boat to an empty tank without skipping a beat.
Blown88GT
Super MS/Extra'er
Posts: 929
Joined: Sun Dec 15, 2013 7:53 pm
Location: South Florida

Re: Ford TFI question.

Post by Blown88GT »

Not necessary if you do what Matt suggested.
Matt Cramer wrote:The MS2 should be sending it the right signal; just make sure your ignition advance is operating normally.

Easiest way to put an MSD box on the car would be to treat it like it has the stock ECU - the MS won't see the MSD, and the MSD won't see the MS. It may be a band aid, but not all cuts require breaking out the anesthetic and stitches.
I have TFI, Crane HI-6 (original model, 25 years old) & hot spark is not an issue.
TFI mod is part of the DIYPNPF60 kit: https://www.diyautotune.com/support/tec ... ord-60-pin

This indicates other issues.
If you unplugged the SPOUT the TFI would make a consistent, hot and clean spark. If the SPOUT was plugged in (MS2 feeding the TFI timing advance information) the spark would be inconsistant, weaker and varied in intensity.
1988 Mustang GT, 59k miles, Orig Owner
ProCharger 600B I/C, 12psi, FRP Hdrs, Flwmstr F2, 3G Alt, Contour Fan & DCC, 3.55's, Prog Sprg, Subfms, UCA, LCA, FCA, Tokico 5's, Bridgestone RE-71R 245/40R17, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, Spartan 2, C&L76mm blo-thru MAF, 47lb FRP-LU47
Post Reply