ignition boxes- what to get?

[rfuerst911sc]

I did a search and found some info but I thought I would ask anyway. I have a project Porsche that did not come with a engine or its accessories including ignition. I have purchased a 911 3.0 with OEM distributor but I need to purchase a ignition box. The car ( 914 ) originally came with a Bosch CD ( 3 or 6 pin ? ). After looking at various Porsche websites there seems to be some negative feedback on MSD in regards to dependability or lack of. So for you guys running various boxes what are your thoughts on stock,MSD,Mallory and Crane? This will be a driver,autocross and DE car. Thanks

[ischmitz]

The 3.0 liter uses a Bosch 6-pin CDI box. The Bosch boxes seem to have a much better track record for reliability. The aftermarket solutions might appear cheaper but some are not even serviceable once they fail. I would go with a stock Bosch unit.

Regards,
Ingo

[RWebb]

compare prices.... you may then get an MSD

for concours you have to get a Bosch

[914efi]

I got an M&W, plugs in to the harness and no problems. Went through several permatunes before the M&W. Had the same situation as you, got the car with nothing. It was about the same price as 6-pin Bosch, but they claim more modern electronics internally.

[Lorenfb]

"but they claim more modern electronics internally."

What a joke!!!!!!!

[JP911]

I went through the same dilemma when I was putting together all of the necessary items for my engine build, and (after much research) I wound up going with Bosch 6-pin CDI boxes. The decision was primarily based on reliability. I purchased 2 used boxes and they have performed flawlessly. If one of them every dies I know I can send it off for a rebuild.

[equality72521]

Originally Posted by Lorenfb

"but they claim more modern electronics internally."

What a joke!!!!!!!

Here we go again.

[trconway]

JP911,

by send it off for a re-build, where would you send it?

Thanks.

Tom

[equality72521]

Originally Posted by trconway

JP911,

by send it off for a re-build, where would you send it?

Thanks.

Tom

Lorenfb rebuilds them, that's why he is always relentlessly bashing after market units. I would never send anything to a guy that bashes the competition though but that's just me. I'm sure he does fine work.

http://www.systemsc.com/

[JP911]

Pelican has a rebuild program (http://www.pelicanparts.com/catalog/shopcart/911M/POR_911M_ELignt_pg6.htm) and I believe others do as well. I haven't specifically looked into all of my options.

[Joe Bob]

Well in all fairness....Permatune isn't called PERMACRAP for nothing....

[rfuerst911sc]

I made an error when I " assumed " that my 914 chassis originally came with a CD ignition it did not. So the factory harness is not set up for either a 3 or 6 pin unit. I know Loren has a strong opinion for the OEM Bosch CD and rightfully so they are very durable. However there are others out there like Steve Weiner and Jake Raby ( pretty good company ) that have good things to say about MSD + Mallory. I looked on Ebay,Jegs,Summit and others and it looks like a new unit depending on bells and whistles is $167.00 - $250.00. I will continue to do my research and keep my eye out for used OEM and see what I come up with. Thanks everyone.

[304065]

I adapted a Bosch CDI to my '66 911 which, like your 914, didn't originally come with one. A wiring diagram is in the below thread. Be careful with the CDI boxes, the output is around 460 volts.

Before there was BHKZ: SWB engine electrics

[ischmitz]

There is something to be said for Permatune boxes that have their internals filled up by black resin. Once a box fails there is nothing you can do about it. It becomes a worthless paperweight....

Bosch CDI boxes use a very simple and reliable design that doesn't fail often unless it sees excessive over voltage or shortages. It hasn't changed much over the years and still rocks. And if one fails it is serviceable.

Ingo

[911Freak]

On my '81 911SC I switched out the Bosch CDI for a MSD, I bought the whole MSD kit 6AL+ Tach adapter + Blaster coil, I for the lifw of me couldn't get the damn MSD unit to work right! I'm sure it was operator error, anyhow I quickly put the Bosch back in and life has gone on uneventfull...

I'll sell my MSD if your interested...

My Porsche mech told me the MSD really works best on "non-CIS" cars... There are many good threads about MSD, Permatune etc. everyone has their own opinions..It seems that more modified engines work best with the "after market units"

Just my .02

[Eagledriver]

I bought the Mallory 6AL for my car. It's cheaper than the MSD and has switches to set the rev limit instead of the "pills". All the CD units can fail and the aftermarket ones fail more often. I carry a spare and ended up using it on a friends car at the track, he had an MSD. 179 from summit racing.

-Andy

[RoninLB]

MSD boxes can get hot. Best to keep them vented imo.

[911pcars]

"There is something to be said for Permatune boxes that have their internals filled up by black resin. Once a box fails there is nothing you can do about it. It becomes a worthless paperweight...."

The potting compounds some manufacturers use to encapsulate circuit boards accomplishes a few things:

1. It reduces vibration damage to delicate electronic compoents, thus increasing service life.

2. Provides a waterproof seal, adds physical strength, resists thermal shock and chemicals, excellent, non-conductive electrical properties and has good flexibility.

3. If black, the potting material tends to mask the true identify of circuit components from prying, reverse-engineering eyes. However, if the perp is so intent, there are ways to identify an IC, resistor or capacitor w/o looking at the markings, even false markings.

Yep. circuit board service is almost impossible after it's potted. However, it's potted to increase service life. So it depends.

Sherwood

[Joe Bob]

What about a Potted Permacrap that fails after 16 months? On MANY units....

[RoninLB]

a local ignition pope said the new model Permatune is much improved.