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Ford tfi/holley dual sync differences

21K views 17 replies 4 participants last post by  Nitrous SSC  
#1 ·
So what is the main difference between the ford tfi and a dual sync distributor?

Whats different about the electronics inside? Is the holley dual sync far superior to a tfi unit?
 
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#2 ·
Totally different animals. The dual-sync uses an optical sensor and is much more accurate. The TFI will work fine with a Holley ECU but the Dual Sync is much better and you can also use it if you decide at some point to convert to CNP. One thing worth noting however- the TFI does not need an external ignition box to function, but the dual-sync does need an ignition box if you are running a single coil system.if you switch to CNP then no ignition box is needed.

I have two Fords with the Holley dual-sync, and am about to do a Terminator X install on my '92 LX which is just a H/C/I setup (no power adder) and I am going to use the TFI for now, will see how it goes.
 
#3 ·
Ok good info thanks. Yeah i want to get the terminator X system for my n/a 427 and see how it does with the tfi distributor but i would like to go coil over plug at some point.hopefully it will work fine with the tfi for awhile.so the optical sensor cant be affected by noise so thats a plus.
Do you feel like your car runs better with the dual sync distributor?
 
#4 ·
If you plan to do CNP, honestly just do it right from the begining and go to a crank sensor and cam sensor setup, and get the 558-118 main harness. I wish I had done that with my 1992 GT. My Lightning is CNP.

As far as how it runs, I did a complete makeover of the driveline, so it would be hard to say, I did a fresh motor, new heads, cam, blower and the Holley HP. I think on a mild setup you probably honestly would not see much difference, but timing errors with TFI seem to be very common one you get a higher and faster revving combo.

I think the X is a nice system for those looking to upgrade from the old tech EEC-IV, but if you have a more radical combo, you might want to pony up for a HP or Dominator.
 
#5 ·
How did you do the CNP setup on your Lightning, Greg?
 
#6 ·
I used some brackets made by a guy on facebook that fit beautifully.

1054283
 
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#7 ·
Soooo... all stock other than the CNP, eh? :LOL::LOL:
 
#10 ·
Thanks man! I don't know about the purring like a kitten part though, have you ever heard a geardriven Procharger up close? They growl pretty loud. When you stand behind it though, it sounds awesome and idles pretty damn good...
 
#12 ·
For main harness I used the 558-118, And for coils and sub-harness I went with the 556-128 "Big Coil" kit



For my combo and power level I felt this was the best way to go, but you can use LS coils and the standard sub-harness and save some money...
 
#13 ·
Greg, so in your opinion is it totally worth spending the extra cash and doing the dual sync and ditching the TFI as I get started with my Terminator X? Rather than waiting and doing it later?


Is this the plug and play version I'd need?
 
#15 ·
Note that Holley EFI has a dual sync distributor, too - #565-202 (or -202BK for the black version) for the 302. I can't tell from their website how the two compare - are the MSD and the Holley the same thing, just with different logos? Or are there noteworthy differences?

I discovered this (but for the 351W rather than the 302) in exchanging emails with Holley tech support. I'm about to send a follow-up asking how the MSD and Holley parts compare. The price is the same, so no advantage to be gained there. Holley's "blank" cap to put on top of the distributor (#566-103) if you're going CNP is about $30 more expensive than MSD's (#84323) - I'm assuming MSD's is plastic, while the Holley one says it's billet, if you care about such things. :) Using the "compare" function on summitracing.com I don't see any differences, but that's only hitting the highlights, so there may be differences in the details.

Edit: Looking further on their website, they have a video that makes it sound like they may be the same thing, just branded differently -
.
 
#17 ·
What's the rest of your ignition setup going to be? I saw in the other thread that you've got a Terminator X (or X Max) coming. Are you going to coil-near-plug, or sticking with a distributor (just non-TFI)?
 
#18 ·
Just sticking with the distributor and 6 series MSD box. I've got an MSD coil as well. I'm not too concerned about going coil on plug. I have the 550-937F that finally arrived Tuesday. But I'm way behind. What was going to be just the Terminator X install has turned into a dart project.