TFI Upgrade Questions

[SCMOOSE]

Just like to say Im the new proud owner of a 91 GW, Im no gear head by any means, but do have some mech skills. I bought the GW in Colorado and I live In South Carolina, so my first mission is to get carb reajusted. My question is about this TFI, and MSD module that Ive been reading about. What exactly is the TFI upgrade and MSD Module. I assume the TFI has something to do with coil / ignition. And MSD some sort of spark regulator, from what I can tell from my Summit book. Are these upgrades worth it, and what parts should I look for to do this upgrade.
Thanks for the wonderful board you have all put together, and you will probably all here from me on a regular basis. Maybe you can turn me into an official gear head.

Thanks Craig Columbia SC

[robselina]

I just did both these upgrades, I'd say they're worth it. The TFI upgrade consists of upgrading your coil, spark plug wires and distributor cap and rotor. You use parts of of a TFI ford setup. IT increases the voltage potential from 20,000V to 30,000V if I remember correctly. You also regap your spark plugs to take advantage of this. The higher voltage gives you better combustion and less missing. Overall, idle and throttle response are improved. The MSD module changes your ignition from an inductive setup to a capacitive system. It's a technologically superior system and can function at higher RPMs but does provide benefits at lower RPMs as well. I've verry happy with the change these two upgrades made, I'd say go for it. If you want a good write up with part numbers check out :

http://www.ifsja.org/tech/electrical/ignitionupgrade.shtml

[coolram]

You can use Conrad premium parts for your cap,rotor and cap adaptor(same quality as MSD for less $$$).Just ask for a '79 Ford 460.The link above gives great detail on it.

[SamoyedSled]

For the TFI updgrade, I've found the link on site (search tfi) and it has photos of everything. Very nice.

Is it true that the only modification for a TFI upgrade is cutting the leads from the coil and soldering to new leads on TFI coil?

Otherwise, it looks like a simple parts swap?

Thanks....

[talntar]

Originally posted by SamoyedSled:
For the TFI updgrade, I've found the link on site (search tfi) and it has photos of everything. Very nice.

Is it true that the only modification for a TFI upgrade is cutting the leads from the coil and soldering to new leads on TFI coil?

Otherwise, it looks like a simple parts swap?

Thanks....yep cut two wires and call it a day. this is like doing a tunup

[SCMOOSE]

The website above sais that this upgrade will only work for up to 90 GW. I have a 91, is that a missprint, or has anyone attempted on a 91?

[Glenn_tx]

Oh boy! I did the TFI on mine the other day and finally got around to re-gapping the plugs today, what a difference. Seems much more drivable now with the T18 tranny. Didn't notice any difference before I re-gapped.

[talntar]

Originally posted by cgrivois:
The website above sais that this upgrade will only work for up to 90 GW. I have a 91, is that a missprint, or has anyone attempted on a 91?i know of no reason it would not.i am sure someone else will know for sure

[Glenn_tx]

Originally posted by cgrivois:
The website above sais that this upgrade will only work for up to 90 GW. I have a 91, is that a missprint, or has anyone attempted on a 91?I'd think if you have the old canister style coil you could upgrade.

[coolram]

Jeep/Chrysler changed the wire harness for '89 to '91 but the TFI upgrade should work for all from '79 on that came with the Motorcraft dist.

[J20DAN]

What is the new spark plug gap after installing the TFI upgrade?

Thanks
Dan

[Glenn_tx]

Seems like .045 was the concensus when I searched the archives. That's what I did mine to.

[89grand]

The new spark plug gap is aprox. .045".

You could try going a little more like .050 and see if you get better results.

I went with .045" after my TFI and MSD upgrade and got very good results. I'd try .050 but some of the plugs are a PITA to get out out so I left them at .045".

[ May 28, 2003, 04:46 PM: Message edited by: 89grand ]

[89grand]

Originally posted by cgrivois:
The website above sais that this upgrade will only work for up to 90 GW. I have a 91, is that a missprint, or has anyone attempted on a 91?This upgrade will work on any motorcrap moduled Wag from '79 to 91. The confusion stems from alot of lists saying to 1990. I don't know why sometimes 91's are left out but they are identical to 89's.

[SamoyedSled]

I think 89grand is correct. 91 gets left off a lot of lists, like skyjackers lift kit, etc..

My 91 has can type coil. So I plan on doing tfi upgrade with tune-up next month.

I noticed MSD has a TFI coil that's $44 versus about 20 for a stock ford unit.

Could the MSD be better? Anyone tried it...

[SCMOOSE]

thanks for the help gents, did the tfi this eaving, finished about 1130. took the beast for a ride around the block and already noticed a differnce, more power, quicker throttle response. Had to come home, gas lite was on, go figure FSG. Cant wait to highway test her. thanks again. will add the msd later on.

[89grand]

Now add the MSD 6A and you'll see even more improvements. I did the TFI by itself for a couple of months then my duracrap module died so I replaced it with the MSD and it runs even better then the TFI only. The TFI is good by itself, just better with the MSD.

[The Anti-Chrysler]

How much did you pay for the MSD 6A? From Summit?

[89grand]

I paid $150 at a local speedshop plus $14 for the MSD motorcrap distributor wiring harness.

I'm sure you can find it a little cheaper from Summit or somewhere but I needed to get one fast so I could return my new duracrap module before it showed any signs of use.

BTW I left the original harness from the duracrap module to the distributor laying there disconnected by the distributor just in case the MSD takes a crap so all I have to do is plug the old harness back into the distributor and connect the old coil wires back to the coil and I'm running off the duracrap again.

This all sounds pretty expensive I know, but just a replacement duracrap module cost me $92 so for me it wasn't really that much more to get a much better and more reliable ignition system.

[The Anti-Chrysler]

Yeah, I giess you've got the weather-paks on your module, so that makes it 3 times more expensive.

Where did you locate the MSD unit? Where the Duracrap was? Couldn't you use the Duracrap harness and place the MSD where the old module was?

[89grand]

I located the MSD unit flat on the right side fender right next to the battery, it doesn't interfer with the hood closing or anything, in fact it fits perfectly there.

You can't use the original harness without keeping track of which wires you need and cutting and splicing them because you don't use all of the original wires. It was much easier to use the MSD harness since it plugs right into the distributor and the other end plugs right into the harness from the MSD not to mention leaving the stock system in place for emergency or in the rare event the I ever sell the Grand I can keep the MSD. The area where the duracrap is is not quite big enough for the MSD, at least not on my rig with all 3 of the window washer containers right by it.

[Puvong]

I did TFI two years ago and this thing performs flawlessly like they said.

http://www.fullsizejeeps.com/jeeps/files/Misc-Pictures/1.JPG

[andy d]

Hey Puvong, great pic of the engine. is that the msd on the left?

[Puvong]

Thanks! You are right, the MSD-A6 is perfectly fit on the left side but I have to relocate one the horn unit.

[talntar]

Originally posted by andy d:
Hey Puvong, great pic of the engine. is that the msd on the left?dont you mean the right.
right side of the pic anywho

[Puvong]

talntar, you are correct that the MSD box locates on the right side of the pic, but it actually mounted on the left side of the engine compartment... when you're sitting in the truck.