MSD, Perma-Tune, or Bosch CDI box?

[dafischer]

So we took the 72E on vacation with us to the shore place last week (about 120 miles from home), and two days in, the CDI (Bosch) craps out. It whines, but no spark. I called a friend who had a spare Perma-Tune which he was able to drop off at mutual friends' who were coming to visit us the next day. Swapped out the box, and it started right up, avoiding the potential for the rollback ride home.

My question is this...which box to buy? An MSD & tach adapter from our host at about $230, a reman Bosch unit from Otto's at $325 exchange, or a Perma-Tune from our host for about $400? Plusses and minuses...Perma-Tune reliablity issues based on some reports here, but plugs right in and seems to run well, MSD performance is reported good but requires wiring mods away from the 3-pin connector, Bosch is OEM and known quantity but reman.

The engine is a 2.4 MFI with 2,500 miles, slightly breathed on with 9.5 comp ratio JE's @ 85mm, stock E cams, Fidanza aluminum flywheel, and SSI's with a sport muffler. What would be your recommendation?

Thanks in advance.

[ischmitz]

Dave,

I'd vote for the Bosch unit hands down but then I am biased. I know the inards of them pretty well. When I repair one it should be good for another 20 years at least. BTW, our host sells rebuilt Bosch CDI units as well. Search for part # A-602-702-00R

I would hesitate to change wiring to install an MSD unit. It sort of messes up the stock look.
Permatune seems to have reliability issues and I have seen boxes that are filled with epoxy resign. You can't repair them when they break. WTF.

Cheers,
Ingo

[dafischer]

Thanks Ingo. Anyone else care to weigh in?

[yamajon]

The 101 Porsche project book states that the MSD set up is an upgrade and that it will improve performance(throttle response etc) my two cents...john

[Charlie V]

I had this personal debate when shopping for a spare box.

I needed reliability because of my love of touring many miles from home. I always travel with a box of tools and critical spare parts.

Permatune was eliminated because of the reliability issues mentioned on this forum.

Wanted the MSD for the enhanced performance aspect. But, the associated $ of purchasing 2 of them didn't meet the budget. Wanted a spare.

Settled on purchasing a used Bosch 6 pin and had my electronics engineer brother recondition the internals. I also needed to keep things stock for my collector plate application on the car.

[T77911S]

there are enough opinions on what is the best one to keep you just above insane.
me, i went with MSD because of price. another plus to the MSD, where ever you break down, chances are there is an advance close by that has an MSD. another option is to have a spare with you. if you do not want your old unit, i am interested in it.

[JK-81SC]

I was looking for a used Bosch to replace my silver Permadoom. I couldn't find any that were affordable. The junkyards are asking $500, since I don't have a core to exchange.

I bought an MSD as a 2nd choice, and I'm copying others who have kept the stock 6 pin connector. That way I can do a quick swap with a Bosch when I find a reasonably priced unit. I'm sure you can do the same with the 3 pin connector on your car, if you go with the MSD.

There is a ton of info on the Bosch on this forum. If you do a search you will find schematics. If you are handy with a soldering iron you can fix the Bosch unit yourself.

[azasadny]

I have had 2 Permatunes fail on me and now I have a Bosch unit (used) installed and a used Bosch unit as a spare.

[Joe Bob]

Bosch....they call Permacrap crap for a reason. I have a couple rebuilt units aviable....both 3 and 6 pin.