Re: STRUCK A NERVE! HEI vs TFI
I knew the question of the TFI module was going to come up when I read it in 'MOTOR'....
We don't use the TFI module, just the TFI laminated ignition coil.
The TFI module is screwed to the outside of the distributor on the new style DuraSpark ignitions.
I don't trust that module yet...
It's like the GM HEI module, it's in the wrong place, being right there on all of the engine vibration, heat, high voltage discharges, EMI & RFI created by the same...
The difference between Motorcraft and GM is, Motorcraft already has upgraded the module twice, and I suspect will do it several more times until the problem is killed.
They did it with the TFI coil, and now it's as reliable as an anvil.
GM released the HEI module in 76, and hasn't looked at it again...
It still has the same problems it had in 76.
Some aftermarket companies like Borg-Warner have fixed some of the stuff, but it was a poor design, rushed to market too soon, and never updated during it's entire production run.
The only upgrades GM did was to it's later models, and those were small...
Delco built a better points distributor than Motorcraft in the 60"s, and Motorcraft built a better electronic ignition than Delco in the 70's.
Motorcraft stayed ahead by updating it's systems, instead of setting on a 60's design...
I have no idea what is coming next, but you bet I'm going to pick the best parts out and use them too!
The Motor craft upgrade is quick, easy, anyone can do it, requires no modification or fabrication at all unless you change the coil, and that is cutting one connector off and attaching another to the same two wires.
No hunting a power source for the so called 'one wire hookup'....
The GM HEI ignition is such a power hog, you really need to use a switched source, and a power relay to do the job correctly, and that's a hell of a lot more than 'one wire'...
If you just use a small gauge wire, you aren't saturating the coil, so you ARE NOT getting the spark energy the sellers say you will...
The Ford stuff snaps right on your existing distributor, no pulling distributors and hoping the guy that modified your GM HEI distributor knew what he was doing and used the right parts...
With the coil upgrade, you have stomped the GM HEI by 1-1/2 times in usable spark voltage.
The Ford stuff will pass emissions in every state I know of. It all looks stock, and it will make your engine run even cleaner than before...
The Ford upgrade can be done at the regular tune up time, so it costs NOTHING EXTRA! Try that with an aftermarket GM HEI! Ask the next guy spouting off about the GM HEI if he will GIVE you one for free, if you buy the cap, rotor and plug wires from a discount store...
(expect that conversation to end abruptly...)
The Ford upgrade sets you up for the next big upgrade, CDI !!
Try hooking up a MSD or other CDI module to a GM HEI...
MAJOR PAIN IN THE A$$!
To be fair, you could use the new GM remote coil, and get nearly the same energy levels as the TFI coil...
GM did a good job with the new remote coil, it's very close in design to the TFI coil...
It's a 4 wire hookup, where the TFI is the standard 2 wires...
and it will require a new module, because the primary resistance is higher...
and you can't use it with a GM HEI with out an adaptor that removes the coil from the cap... (Like ford has all along...)
So, if the Ford upgrade gives better performance, more useable spark energy, better control of the energy, cost a bucket load le$$, and can be done by ANYONE with Forest Gump's I.Q., and replacement parts are available for it in every parts store, and it is emissions legal, I don't see the need to go to the GM HEI...
Someone correct me if I'm wrong, but I don't see a down side to this...
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JUST LIKE I HAVE ALWAYS SAID, IF YOU HAVE *ANY* DOUBTS, DON'T DO IT !!
If you can't cut two wires and reattach two others for the coil upgrade, DON'T DO THE COIL UPGRADE.
If you can't take the plug wires off and put them back on in the same order, or you can't change the distributor cap and rotor, DON'T DO THE CAP UPGRADE.
That's all there is to it.
No pulling the distributor or fabricating parts, no buying expensive aftermarket parts, no trying to follow instructions that go in circles, no missing or sub standard parts from suppliers trying to save a buck, or instructions telling you to connect to wiring that is too small to supply the GM HEI unit properly...
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If you can't do those basic tune up things, cap, rotor, plug wires, ect, you can't install a GM HEI anyway, so the entire concept of the GM HEI being simpler is insane...
My upgrade is so simple that some people can't get a grip on it...
I get 25 to 50 emails a day saying the same thing, "Did I miss something? Is $60 or $80 all it's supposed to cost? Why didn't I have to take the distributor out? Why didn't I have to cut into my wiring harness?..."
Everybody has been so abused by the aftermarket people they can't grasp the idea of the upgrade....
Also, they seem to assume because I gave the information away for free, it's worthless, except for a few of the guys here that caught on real quick, like Black Jack, Snow Tow, CJ Dave, Dirt Dog, and a few others..
If it weren't for them asking questions right away, I would have given this upgrade up a long time ago. Just wrote it off as being to technical for the readers here...
Glad to see I was wrong!
There are still a few mouth breathers that just won't get it no matter what you show them or say to them, and the guys that feel they have to defend the $$ Mega $$ purchase they made in the GM HEI, but for the most part, most of you have done a pretty good job of doing a 180 degree change in the way you have been told and were thinking....
Those 180 degree turns are really hard to do!
It's hard to take someone's word you don't really know, for something you don't really know anything about...
For the first guys that did it, it was a blind leap of faith, and I thank you for it.
I hope I explained what was going on well enough that you now understand, not only how to do the upgrade, but why it works, and why it's so much better than stock...
Good job folks, keep up the good work...
Aaron.
If Chris Columbus "Discovered" America (with 25 million already here), Can I Go "Discover" Florida?