'69T Kettering to Crane CDI Ignition

[Fishcop]

Hi All

I'm in the process of rewiring my "uniquely wired" '69 car. Basically I've stripped the loom/harness completely to clean the wires, clean/replace terminals, renew shrink wrap etc... Long slow process, but it seems to be coming along well.

My real question relates to the Crane XR700 CDI unit I use, which I installed 10 years ago and has been terrific. I seem to have a lot of superfluous circuits related to unused relays, the old sportomatic wiring and the T's Kettering ignition (in 69 the E and S got CDI).

I'm interested to know what I can delete off the electrical board on the left side of the engine compartment. There appears to be an old ballast resistor, a starter relay, and a rear de-misting relay (I'll keep it, though it's never used in my climate). Does anyone happen to have a circuit diagram or photos to wire the Crane unit in nicely?

Any other advice is greatly appreciated.

[edmayo]

Since you asked,,,,,my advice is to keep all the original wiring, it doesn't hurt anything, but also I'm not fond of the Crane optical unit because it involves that extra unit that needs to be dealt with. I prefer the Pertronix since it is all in the distributor with no extra boxes to mount and wire.

[Fishcop]

Thanks Ed

Unfortunately a PO did "stuff" to the wiring that I'm only now trying to clean up (removing previous alarms and stereos has taken days!). I'm attempting to keep it as stock as possible (even using a spare loom retrieved from another car for the correct colours etc...). However I'm committed to keeping the Crane as it's worked very well for nearly 10 years and it's all I've got

Am I right in thinking I can delete what I think is the ballast resistor (alloy can with two terminals marked D+ and DF)?

Cheers

[Fishcop]

Actually what I'm referring to as a ballast resistor I think is referred to as a regulator on my wiring diagram... Same question though, can I delete it if I'm running CDI?

[edmayo]

John I think what you're referring to is a capacitor for the alternator, often installed near the voltage regulator. The D+ and D/f are designations for alternator /voltage regulator. Is this alloy can about the diameter of a quarter (or whatever passes for a quarter in Aussie land) and about 2 1/2 " long? If so I'm sure that's what you have there. It's purpose was to eliminate static interference at the radio from the charging alternator. I feel your pain, I have never seen such mucked up wiring as what can be done installing radios and alarms.

[classic]

John,

when you get it sorted out, come down and figure out mine will ya? Mine had a CDI fitted, rather than the standard setup for a 69T.

[Fishcop]

Thanks again Ed

No worries Tony. If I don't blow my electricals, then I'll know I have it right

[304065]

John

A couple points:

1) XR700 is not a CDI ignition, it's a transistorized electronic ignition with a built-in optical trigger. We discuss this extensively here:

http://forums.pelicanparts.com/porsc...discharge.html

You can read more detail at that link but the long and short of it is that the unit runs out of steam at 6500 rpm, right when you need it the most, and the optical trigger has limitations vs. a magnetic hall-effect type.

2. 69 cars had a unique, one year only design for the electrical components in the engine compartment. There is a great deal of value to be gained by having things correct back there-- both in terms of your ability to diagnose electrical issues AND the peace of mind to you or a subsequent owner that you're not going to have a meltdown far from home due to some prior owner's hackjob. (It's ALWAYS the prior owner that does a hackjob )

3. I would start by photographing everything you've got. I'm very interested to see how the T differs from the E and S due to the lack of components related to MFI, i.e. Speed Switch? (Some later Zenith Ts used one, your Weber T probably not)

Simplifying can be done allowing you to revert back to the original if the time comes.

[Fishcop]

Wonderful info thanks (though it did stretch my math ability )

I'd love a photo of a complete and unmolested 69t engine bay console... When I bought my car 12 years ago it had the Marelli distributor, points and condenser; however the cap had a crack and I found that parts were NLA. So I machined a later 2.7 Bosch distributor down to fit the early engine as NOS or correct Bosch units are much more expensive - the distributor was regraphed accordingly.

The electrical console was missing all the fuel filters and pumps (I know they're different again to the E and S), and it has a "Made in Australia" Bosch square shaped unit with "RE" embossed on it and the D+ and D/f terminals (which I thought was a ballast resistor). The Porsche round relays for 'start' and 'rear demister' were all missing and replaced with Hella square units. There was no other electrical components other than the 3 fuse box (sportomatic).

The car has always been a hotrod with me saving it from the "forward dating" path it was on. It meant that I lost a lot of period interior and anodised trim which over the years I've been addressing. The car has run a webered 2.7 RS spec engine and 915 box for the past 7 years.

I purchased the Crane (perhaps naively) 10 years ago thinking it was a CDI cure-all. I have to say that the car has run like clockwork since. But as a part of my full nut and bolt rebuild, I'm rewiring the car as closely to factory as possible. All wiring is getting mil-spec fireproof braided shielding and all terminals cleaned up, replaced if necessary, and new heatshrink insulation where appropriate. Given the nature of the car, it can never really be considered original so I have been happy to make sensible upgrades such as improved ignition and add period correct features.

So at this stage it apears I should consider adding MSD/CDI and using the XR700 as an ignition component...

Keen to hear about/see a "hotrod" solution in the abscence of a correct Kettering set up.

[Fishcop]

Okay, I've confirmed that the square box on my console is indeed a voltage regulator, I thought the early cars had a regulator built in with the alternator? In any case, I suspect I cannot delete this item with a switch to CDI (MSD/Permatune etc...)

John?