FAST XFI tuning question - Page 7 - Lateral-g Forums

John S · #61 11-13-2009, 04:53 PM

Ok, So obviously Me and Rich are not the only ones that have had problems with Dual Sync distributors.
What are our options?
As I said I was considering going to a crank trigger (my original choice before I got talked into the dual sync) or even looking into a LS style coil over plug setup. I do know that FAST sells a controller for this type of system but there are a few other issues to work out.

What to do about the oil pump drive?
How can you dress it up a bit on a 1st gen 23* engine

On # 2 I ask before I have not seen anything that makes the coil packs look decent. But I do admit I have not looked into it very deeply yet.

Any suggestions?

**GregWeld** · #62 11-13-2009, 04:59 PM

Try an Accel dual sync distributor??

John S · #63 11-13-2009, 06:03 PM

I'm tired of "trying" things hoping they will work. I really do not have the money to throw around on something that "may work" and I have read of others having problems with the accel dual sync as well.
Sorry if I sound a bit frustrated but like many others I've got boxes of parts sitting in the garage that did not work for one reason or another and at this point (and age) I would like to be able to enjoy driving my car without worrying if something like the distributor is going to fail again after no more then a couple of hundred miles.

67ragtp · #64 11-13-2009, 06:28 PM

John,

I really cant see myself going to a coil on plug conversion by the time you add up the cost of external boxes and coils and crank triggers it just aint worth it. Dont have any clue how you would get a cam sensor in there to run sequential. This system has cost a ton already, got to cut my loses now.

If I understand your problem corrrectly it was predominantly mechanical, and you were able to resolve it with some design change. The real question is, is the electronics reliable? I have considered purchasing another one and tearing it down to the housing and possibly welding ears on it to bolt down the cap and adressing the issue you had as well. Maybe even keep the one in the motor now as a back up.

Im shocked that msd has not come out with a distributor like the one we have only better.

Rich

wedged · #65 11-14-2009, 05:53 AM

here and idea: pull the crank damper off, have it index drilled for insertion of rare earth magnets, make a crank trigger pick up mounting bracket, cut off all but one of the reluctor teeth in the distributor. Now you have a crank signal and a cam signal. You could also just use a trigger wheel and a pick up.

I had partially done this on my 440 with XFI- I did not modify the distributor. I was testing the crank trigger to make sure it worked ok. It did not. The magnets i used were too small and would loose power when hot. I switched the wires back to the distributor for the crank signal for now. At some point I will put in larger magnets or add an aftermarket trigger wheel.

John S · #66 11-17-2009, 11:58 AM

Not sure if that will work with the FAST Dual sync, the pickup is a hall effect and runs 8 crank magnets and 1 cam magnet in a molded plastic housing.

**GregWeld** · #67 11-18-2009, 08:38 AM

So here's the answer you're looking for -- YOU DO NOT need a dual sync style distributor if you run BATCH FIRE. You only need a dual sync distributor for running SEQUENTIAL.

That help??

How's that for a simple solution? Just junk the dual sync - and run a good old fashioned MSD.. Just make sure you're running Batch Fire, and you tune accordingly.

wedged · #68 11-18-2009, 09:04 AM

I'm running sequential with no cam signal. I decided to do this to not have big spikes in pressure from batch fire. I have no idea if it makes a real difference.

**GregWeld** · #69 11-18-2009, 09:12 AM

Quote:

Originally Posted by wedged

I'm running sequential with no cam signal. I decided to do this to not have big spikes in pressure from batch fire. I have no idea if it makes a real difference.

I was just trying to answer the original question - which was - how to get rid of the dual sync distributor. And the easiest way for him to do that - is to just run a "normal" distributor and run batch fire. Unless he's trying to maximize fuel milage - or trying to pass emissions etc - there's no reason to HAVE to run sequential. His beef is with the dual sync. So my answer is a simple, straight forward, cost effective way, which is what I think he was looking for.

Pantera EFI · #70 11-23-2009, 10:05 AM

I have been using my OPD with a 48-2 target for YEARS.

The one Hall sensor will provide for sequential coil AND injector operation, "Gear Down".

Those that fit a Degree Based (720) EMS can also benefit with one injection event in each cylinder WITHOUT a cam sensor.

There are some EMS that can "find" engine phase without a Cam (phase) input, my EMS can do this work.
This is done for safety reasons, though I do support that feature. (INDEX input)

Lance