Conversion to point-less ingnition

[cruiksdr]

Long live old threads!!

Okay folks, I just ordered the Crane Optical Pickup Trigger (said to be a good alternative for those of us with permatune). Any of you done this (losing the points using the crane trigger but useing the permatune instead of the xr700 box)?

What can I expect from this? I have a 2.2T (high compression) with Webbers. The thing runs rich (I go through plugs like toilet paper!). It's very difficult to start when cold and does a lot of sputtering and missing. At speed, it's pretty good but does still miss some. I'm hoping to see improvement -- better spark, more burn, more efficiant ignition, smoother running (esp. at low idle). I've spent a lot of time looking through postings both here and on 911BBS, and I'm seeing mixed messeges -- mostly good, but it's not clear what I can expect with the optical trigger and permatune.

What are your experiences??

Thanks!
Daniel

[van914]

Barry,
As the former owner of your Kick Ass 914-6 I have a few suggestions. If you line up the flywheel mark to TDC and pull the Distributor you are halfway home. Are you using the X-700 kit or just the optical trigger and the Crane HI-6 or what ever replace it? Crane does make a box the onlu uses the optical trigger to fire the box. The hard part of the install as said before is lining up the optical trigger and the shutter wheel so nothing rubs. I have used thei system in my 4 cly car for years. Once it is set you can forget it. I am glad you are enjoying the car. I still have panges of regret. I am now converting the 74 to a six with a simular moter to what is in your car. Happy Thanksgiving and keep the top off and your foot in it..
Van

[Dave at Pelican Parts]

I would not expect much from the Crane setup on a 911 motor. By 1970, when your 2.2 was made, I believe that the 911s all had capacitive-discharge ignitions. They already have a fairly high-energy ignition system.

The Crane will likely make the ignition timing a little more prcecise, and you'll never have to change points again, but that's about it.

The four-cylinder cars use a conventional Kettering ignition. The points directly trigger the coil. The problem is that the points are kind of "sloppy" about doing that. Going to an electronic points replacement makes the "quality" of the trigger much more precise, so you will get a better spark out of the coil.

But a CDI will produce a spark that is better yet, and you already have that.

Like I said, I wouldn't expect too much out of the conversion. I doubt it will instantly solve all of your problems.

--DD

[J P Stein]

I use a Pertronix (or however it's speeled) for points and an MSD 6AL ignition system.

The Pertronix thingy has been doin' it's job for bout 4-5 years now. No complaints there.

The MDS unit IS the hot setup.....if you have carbs and a cam with
more than a little overlap. Prior to installing one, I was having all kinds of low rpm running problems. I dicked around for months
trying to tune the thing, but was fouling plugs constantly and it was herky-jerky while running on the idle circuit/transition.

Bought the MSD, set it up pretty much as they said, bingo. Now the motor will sit and idle till hell freezes over without fouling the plugs.....smoothed out the low rpm probs, too.....OK, it's a bandaid for lousy AF mixture, but I'll take it.

[cruiksdr]

At this point, even if I don't see much improvement with low end running smoothness, it's worth the $$ and the time to install if it means not having to do the contortion act to get at the dizzy to adjust the points anymore. I'm getting old (okay, maybe 40 isn't that old, but when was the last time you tried to get back into that thing!), and I can't see myself hanging off the trunk head jammed into the firewall and twisting myself like a pretzel too many more times. I'll take anything I can get.

How is the MSD unit different from the permatune? Would it be worth switching to the MSD or the XR700? Will the MSD cause me to lose my tach as I've heard that the crane does?

My understanding is the the Permatune is a high energy, multispark unit that should be giving me good spark. I've also seen discussed on this forum that some folks are gapping their plugs to as much as .060. I've been setting mine at .027. Would a larger gap help?

I've worked with my carbs a lot (and so has my mechanic). According to Chris at PMO, mine are jetted exactly where they should be, but it still runs rich. Seems like stronger, more efficiant ignition might help.

Thanks you all for all your help! You're all great! I'd be lost without you all.

Okay, I'm getting weepy -- better go : )

[J P Stein]

My bandaid.......a rerun for many

MSD 6AL
MSD High Vibration coil
Magnecore 8.5 mm wires
NGKs (pick your heat range) gapped to .045

The MDS coil puts out 40K+ volts vs 20-25K for the Bosch.
The Bosch will not jump that .045 gap at high rpms (or so I'm told). The fat wires are to get them volts to where you want them to go.

A side note: My 2.4L T (Webers) motor ran fine with the Permatune CD & Bosch coil, std wires, std gap for plugs.

Starting mine is a b!tch when it's been sitting for a week or more.
If I run it each day (up to opperating temp) it starts fine, but not as well as an injected car.

[Dave at Pelican Parts]

The MSD is a CDI (Capacitive-Discharge Ignition) setup, just like the Permatune. The difference is that the MSD has more electronics in it that will trigger more than one spark at lower RPMs. These all theoretically come during the combustion stroke (maybe some on exhaust??) and should help keep the mixture burning, or re-light it if it doesn't start or goes out. This is most often a factor on engines that run rich.

At higher RPM the time you have to do this sort of stuff is reduced. So the number of sparks gets reduced depending on RPM. At some point (maybe 4000 on a Six? I dont't remember...) you're back down to one spark, which is exactly where you are with the Permatune.

No idea on the tach compatibility.

--DD

[M. Hendrix]

Now that is interesting. I think I need that.

Hmm..


M

[J P Stein]

Dave, you're right.....well, it's 3000 rpm, but that's not important now. The big plug gap is for low rpm work, but it's still there at high rpms and one needs to support it(voltagewise).

The MSD won't do anything for an engine that has a well controlled A/F mixture. Unfortunately, Weber carbs (the 3 barrels, at least) don't do a good job of this. I (and I suspect many others) am forced to run them rich on the idle circuit......it's a stinky SOB. The 2.7L ran on the permatune, just not well( below 3000-3500).

The difference with the MSD was dramatic.
I was skeptical of the whole multiple spark thing till this set-up was recommended by a local guru....and I was getting desperate.
Nobody likes throwing away plugs after 100 miles.....sitting at a stop light and having clyinders drop.....augggh.

Once we're on the main jets I can't say I noticed any difference....tho I run rich there also....a saftey margin thing for 9.7:1 compression.

[cruiksdr]

Will the MSD work with the crane optical trigger?

[J P Stein]

I don't see why it wouldn't. The MSD install instructions have a section on optical triggers. Crane makes a CD unit also, but have no experience with them.

BTW, my tach hooked up without an adaptor. It's previous life was in a 71 9eleben.

[scg]

The 2.7L ran on the permatune, just not well( below 3000-3500).

Damn!

[J P Stein]

Originally posted by scg
Damn!

Scotty, as I recall you have mild cams. CIS? If so, you shouldn't have much problem. I have a friend with that set-up and he didn't have to go thru this BS......of course, he's down a *few* hp from my set-up....no big thing....40-50 hp

[scg]

Yeah. I'm not having those problems right now...but I'm planning ahead (I've got a spare engine and tranny I'm tearing down/rebuilding)

[elwood-914]

Hi guys,

It just so happens that I'm putting in the XR3000 this weekend and I have a question, which shutter disc is used with our Bosch's? The one with 4 slots and retaining springs? Or the 4 slots and no springs? Like in prevous posts the instructions are not too clear. I have an led light on the end of the XR3000 module, it has a solid red light, is that normal? I also changed the coil to with a crane suggested model. Thanks

[Dave at Pelican Parts]

I wound up using a shutter that had four straight-cut slots (there was another one with six curved slots on there when I bought it), and had four areas with "teeth" on the inside of the hole. The "teeth" went into the areas between the distributor cam lobes.

--DD

[cruiksdr]

Help! Got my optical trigger and got it into the dizzy. Now for wiring.
As previously mentioned by others, the instructions are not so clear. I am using the permatune box, and the instructions that came with this don't even mention permatune.

Any wiring hints trigger to permatune would be greatly appreciated!

Thanks!

[scg]

wired it up to my permatune and the rest of the electrical system as shown in figure 31 in my Crane manual

That should help...now back to lunch an then gas tank removal (woo-hoo!)

[cruiksdr]

Okay... Time for the idiot question of the day. Fig. 31 shows the XR700 Ignition Module (trigger --> XR700--> permatue). Does this mean that the trigger won't work without the XR700?

I don't have the XR700. I purchased the trigger kit here at PP. From the description, I got the impression that this would work. I have a sinking feeling that this was a mistake.

[scg]

D'oh! I'm such a dumbass...sorry! It looks to me like you get to choose which of these http://64.90.9.168/cranecams/pdf/90002006.pdf three diagrams looks most like a permatune.

According to permatune, the connections on their unit are:

A = + or 15, coil hot primary terminal ( - or 1, coil ground primary terminal is connected to the engine ground).
B = Power from ignition switch.
C = Distributor breaker points.
D = Ground

My WAG has it (from trigger): RED wire to "B" (do you have a ballast resistor? Is it needed? I have no clue) ==> WHITE wire to "C" ==> BLACK to ground

...good luck. Maybe somebody else will have a better idea.