MSD - CDI box rusting points which then break

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Rob911T
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MSD - CDI box rusting points which then break

Post by Rob911T »

I have a 1971 Porsche 911T - 2.2litre.
It is originally a USA car which was imported into the UK in 1993.
The car is running Zenith carburettors. The USA emissions kit has been removed from the carbs.
The car has an MSD - CDI box with Blaster coil.
I purchased the car in August 2022 , after it had been fully dismantled , media blasted , rust removed, re-pained and rebuilt.
I have spent the winter sorting lots of small rebuild issues you would expect following such a deep restoration.
The car is now in good order and now runs well ....BUT .....it has burnt out 2 sets of points in the last 3 months....leaving me stranded beside the road.
With the MSD ignition system, I understand that ozone is created within the distributor cap due to the high voltage and multi spark scenario....and the air is electrified due to the high voltage, I understand from research.
This together with the heat, causes condensation, which when combined with the ozone causes rapid rusting and deterioration of metal...hence the broken points.
MSD suggest a fix, which is to drill 2 holes in the distributor cap to dissipate the ozone and electrified air.
However, with the rain in the UK, that causes wet weather running issues, such as misfires and can stop the engine working at its worst.
The car originally had 2 holes in the distributor cap, and I replaced it with a new cap to solve the rain issues....seems I have now re-created the ozone rusting / points breaking issues.
Does anyone have any similar experiences?
Does anyone know of a fix for these issues?
Any suggestions for the ignition system would be appreciated.
I have been advised to scrap the MSD system and move over to a Permatune system.
Does anyone have any experience with a Permatune system?
I would look forward to hearing from you with ideas or assistance
Many thanks
Rob911T
Ian Comerford
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Re: MSD - CDI box rusting points which then break

Post by Ian Comerford »

I have no experience of this due to having a later car but is the 123 distributor an option for your car? It gets rid of the points and I would guess this issue.
https://www.scparts.co.uk/sc_en/warehou ... ZpEALw_wcB
Rob911T
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Joined: Sat May 27, 2023 3:22 pm

Re: MSD - CDI box rusting points which then break

Post by Rob911T »

Hi Ian
Thank you for getting back to me.
I think I would need to change CDI box too, because the creation of ozone will still occur in the dist cap...and could corode the rotary spark creator in the same way as points
I am looking at Permatune for CDI box, distributor and coil.( a matched set)
Looking for other peoples experiences with ignition issues ....or different CDI systems
Regards
SeanP
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Re: MSD - CDI box rusting points which then break

Post by SeanP »

Why change the MSD?
123 distributor has no mechanical points to rust. Lots of cars run a 123 distributor with CDI MSD Bosch or otherwise.
The Permatune distributor looks very much like a 123 distributor. Have no real knowledge of Permatune so cannot comment. But I do have a 912 and a 911 both running on 123 distributors with no issues.

Give Jonny Hart a call over at classic retrofit. He should be able to put you right
1966 912
1969 912/6 hotish rod in build
1974 914 Dead
LI 125 Lambretta (Yeah right it’s a 125)
Mini Cooper s
Rob911T
DDK Newbie
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Joined: Sat May 27, 2023 3:22 pm

Re: MSD - CDI box rusting points which then break

Post by Rob911T »

Hi Sean
Thanks for your thoughts.
Have spoken to Jonny at Classic Retrofit. He feels that the MSD CDI ignition system can be troublesome. His thoughts were that with the MSD CDI operating at 'north of 45,000 volts' and using multi sparks to 3000 revs
this would create issues. Firstly he feels that there is 'flash over' into the distributor. Perhaps because of 45,000 volts and multi spark....the original Bosch system ran at 35,000 volts and single spark.
He also explained that for every spark, ozone is created and the ozone created by very powerful MSD multi parks is considerable.
Ozone can corrode metals ( as in points) but also plastics as in some electrical rotary ignition systems.
Hence my view that the MSD system has to go. Fully understand that other folk may use it with no issues. Perhaps it is down to the individual 'set up'....and how you use the cars.
I have done 3000 miles in 8 months and all types of weather, rain hail and shine.
The Classic Retrofit CDI+ box is £895 Plus VAT. A standard coil is need for it to work at circa £150 plus VAT. At £1045 plus VAT...... I am still left with my old worn original distributor and wiring harness.
The Permatune kit if bought as a pack ( distributor, wiring harness , coil and MSD box ) is £1121 plus VAT. So, a complete new ignition system for about the same price as a 'part new' Classic Retrofit set up with my old distributor / harness.
Just wondered if anyone had experience of Permatune as an ignition system.
Regards
Rob911T
Ian Comerford
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Re: MSD - CDI box rusting points which then break

Post by Ian Comerford »

Have you tried a search on Pelican where you will get a higher number of Permatune users? You will have to filter the fact/opinion/myth as usual but will get some useful comment
http://forums.pelicanparts.com/porsche- ... e-msd.html
Rob911T
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Joined: Sat May 27, 2023 3:22 pm

Re: MSD - CDI box rusting points which then break

Post by Rob911T »

Hi Ian
Many thanks for contributing.
However, I Just cannot face the rubbish you find on many Pelican threads.
Hence participation on DDK where sense prevails
Regards
Rob911T
SeanP
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Re: MSD - CDI box rusting points which then break

Post by SeanP »

Rob

My question on the Permatune ignition would be what support is offered in the UK for an item manufactured in the USA?
Looking at Permatune’s web site the distributor looks like a 123 ignition item to me. The box is the standard Permatune affair, and the coil who knows.

Classic retrofit are in the UK and I know that Jonny is more than helpful and supports all of the items he sells fully. Is that not worth the additional cost?.

You could buy a 123 ignition distributor and install that with a standard Kettering coil setup. That gets rid of your distributor issue. Then add in CDI and coil as you see fit.

What coil is the MSD system running at the moment? If its a MSD 8222 coil then its all good for a Bosch/classic retrofit CDI.

Regards

Sean
1966 912
1969 912/6 hotish rod in build
1974 914 Dead
LI 125 Lambretta (Yeah right it’s a 125)
Mini Cooper s
Ian Comerford
I luv DDK!
Posts: 767
Joined: Fri Apr 01, 2005 8:51 am
Location: Harston, Leics

Re: MSD - CDI box rusting points which then break

Post by Ian Comerford »

I would just check that last statement with Jonny as I had an 8222 on mine when I fitted the CDI+ and he suggested it wouldn’t work as well as a standard black Bosch coil, giving either fewer sparks or less strong I can't recall which.
SeanP
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Posts: 758
Joined: Thu Sep 06, 2012 11:59 pm
Location: North West Essex

Re: MSD - CDI box rusting points which then break

Post by SeanP »

It’s probably a less strong spark as the resistance is not the same but its a better coil than what has replaced the standard porsche coils on the market.

Its epoxy filled though so wont leak oil everywhere when it over heats.

The other option is to buy a secondhand Bosch black coil
1966 912
1969 912/6 hotish rod in build
1974 914 Dead
LI 125 Lambretta (Yeah right it’s a 125)
Mini Cooper s
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