MSD back to CDI - Help

[ivanuf]

Here is a pic of the engine out of the car. The car is not a numbers matching engine, from what I can tell the bottom end is from a 86 Turbo, but all else is from a 77.

The engine was running smooth and strong. So I guess it was sorted out in the past. I will leave as is. The only change I want to make at this time is take the MSD out and put a 8-pin CDI back in place (period correct). I was told that a 6-pin will also fit, the only difference will be on the grounds and some changes needed to be done to accommodate the 6-pin plug, but the harness has the 8-pin and the car is 77 so I will prefer an 8-pin CDI.

[356911930]

You should look-up the part number of your distributor an see if it matches your 1986 turbo motor or exactly what it is . How could your engine run smoothly with the star wheel in the distributor mangled like that?

Rahl

[356911930]

Cheapest 8-pin I've seen in a long time. $875 ebay

Porsche 911 Turbo 930 CDI Box, 8 Pin HKZ Bosch 0 227 300 003 | eBay

Rahl

[ivanuf]

I will verify the distributor part number and keep researching!, Thanks

[Speedy Squirrel]

So that makes sense. The engine is a 1986 turbo with the counter-clockwise distributor drive. Your distributor is - 237 304 -16, which is a PORSCHE 911 3.0 SC 1980 to 1983 distributor. It can be converted to a turbo distributor, and may even have been.

It appears that you have never had this car running.

The 8 pin wiring diagram is shown below, but I don't think you should go that route. Your car will never be super-collectable with the wrong engine. The newer engine is readily identifiable to a collector due to the case number and the lack of a oil sump cover plate. The 6 pin Bosch CD box is much more widely available, and easy to install.

From the ignition viewpoint, I would do the following:

Get the distributor rebuilt, and set up for the 1977 turbo advance curve.

Get the correct distributor to CDI box green wire. They are readily available.

Either keep the MSD box, or get a six pin Bosch CDI box. Don't worry about changing the connector and the contacts. All of those parts are available.

[ivanuf]

So that makes sense. The engine is a 1986 turbo with the counter-clockwise distributor drive. Your distributor is - 237 304 -16, which is a PORSCHE 911 3.0 SC 1980 to 1983 distributor. It can be converted to a turbo distributor, and may even have been.

---You are probably right

It appears that you have never had this car running.

---But, the car was running, I drove around on it several times, the only problem was a stuck wastage. But otherwise it felt normal and super smooth idle!

The 8 pin wiring diagram is shown below, but I don't think you should go that route. Your car will never be super-collectable with the wrong engine. The newer engine is readily identifiable to a collector due to the case number and the lack of a oil sump cover plate. The 6 pin Bosch CD box is much more widely available, and easy to install.

---I agree, it will be a car to enjoy, not concourse. But anyway I got a proper 8-pin core from a fellow forum member that I plan to use.

From the ignition viewpoint, I would do the following:
Get the distributor rebuilt, and set up for the 1977 turbo advance curve.
Get the correct distributor to CDI box green wire. They are readily available.
Either keep the MSD box, or get a six pin Bosch CDI box. Don't worry about changing the connector and the contacts. All of those parts are available.

---Sounds like a plan! With the 8-pin instead of the 6-pin

Thanks for the guidance, I was at a lost!

[Jonny H]

If you want to keep the car original looking, we can rebuild 8 pin boxes with our fully programmable multi spark electronics inside. You can then lock the dizzy (dont need to recurve) and set your own advance curve:

http://www.classicretrofit.com/products

[ivanuf]

As I look into your web site, I need to send you the 8-pin box and you will do the electronics for 1,700 pounds + shipping + currency exhange rate? Why the higher price vs. your 6 pin conversion.

And what makes your upgrade worth 1,200 pounds more than the similar service provided by partsklassick?

https://www.************.com/p-1799-bosch-8-pin-cdi-refitted.aspx

[Bucketlist]

Ivanuf, have you checked with TACH-ADAPT
I thought Bob Ashlock was the expert on these.
Just check him out.

[Jonny H]

Originally Posted by ivanuf

As I look into your web site, I need to send you the 8-pin box and you will do the electronics for 1,700 pounds + shipping + currency exhange rate? Why the higher price vs. your 6 pin conversion.

And what makes your upgrade worth 1,200 pounds more than the similar service provided by partsklassick?

https://www.************.com/p-1799-bosch-8-pin-cdi-refitted.aspx

Design rigor, true multi spark, comprehensive features and a flawless reliability record.

Just like engines, it's what's on the inside that counts.

[ivanuf]

Jonny,

Form a user (customer) that is not an expert on the topic.

I do not understand the following:

1. I was told that a 6-pin unit provides the same functions of the 8-pin, the difference was on the ground points. That for a street car a 6-pin or 8-pin will do the same work.
With the correct wiring changes. So why the big price difference for your service from 6-pin to 8-pin. (1,000 pounds)

2. For a street car with no need for true-multi spark, is there a OEM factory equivalent option?

3.Comprehensive features ?? Please elaborate..

4. Flawless reliability is backed by warranty, the other vendors offer 5 year unconditional warranty, what is your warranty?

Ivan

[ivanuf]

Hot Euro,

I will send the info also to TACh-ADAPT to see their recomendations.

I have not heard about them before.

Thanks
Ivan

[Bucketlist]

Originally Posted by ivanuf

Hot Euro,

I will send the info also to TACh-ADAPT to see their recomendations.

I have not heard about them before.

Thanks
Ivan

You can email him at: Bob@AshlockTech.com

[Jonny H]

Originally Posted by ivanuf

Jonny,

Form a user (customer) that is not an expert on the topic.

I do not understand the following:

1. I was told that a 6-pin unit provides the same functions of the 8-pin, the difference was on the ground points. That for a street car a 6-pin or 8-pin will do the same work.
With the correct wiring changes. So why the big price difference for your service from 6-pin to 8-pin. (1,000 pounds)

2. For a street car with no need for true-multi spark, is there a OEM factory equivalent option?

3.Comprehensive features ?? Please elaborate..

4. Flawless reliability is backed by warranty, the other vendors offer 5 year unconditional warranty, what is your warranty?

Ivan

Hi Ivan,

1. The Bosch 8 pin box is superior to the 6 pin box. It was used in the racing and early Turbo and has a constant voltage output at all RPM whereas the 3/6 pin boxes voltage is dependent on RPM (less at high RPM). It also has greater spark energy.
Some units also have a built in rev limiter. True, that the later cars all went to the six pin but there is no denying that the 8 pin box is a better unit. For comparison, our units are also constant voltage output unlike other units in the market. Our 8 pin units cost more as they are built to order.

2. The MSD unit in your car at the moment is 'multi-spark' but only to 3400 RPM and the spark interval is 1ms. IMO, an interval of 1ms cannot make a great difference to combustion beyond around 3000 RPM which is why MSD units revert to a single spark at 3400. BY contrast our units fire the second spark at 400us. (2.5 times faster) and o 10,000 RPM. This improves power right across the rev range. This is absolutely noticeable and a great improvement for a road car.

3. Too many features to list here but it is all in the PDF manual which you can download from this page: 911 CDI+ (6 Pin) - Classic Retrofit

4. We will warranty a road unit up to a maximum of 10 years as long as it stays on the same car. The units are soon to carry the CE mark as they exceed the standards for EMC emissions and susceptibility.

[ivanuf]

Ok, thanks for the replies.

I contacted Bob, and he indicated that he was there if I needed his services and suggested I did so via the host, but he did not worked with distributors.

Jonny, thanks for all the replies and information but 1,795 pounds is a bit too much for my budget of the CDI repair.

Then I contacted Kurt Donohoe, at parts klassic and he was super helpful and very knowledgeable of what I needed to do. He can do both services at his shop and send me a sorted rebuilt distributor and refurbish my CDI core with new electronics.

I sent the parts to Kurt, and keep you all posted on the results of the installation

Ivan

[ivanuf]

Update:

After several conversations with Kurt we decided to install a brand new 3.3 distributor to add the advance and retard features of the 3.3 engine. Kurt also replaced the inside of the 8-pin CDI with his digital version. I will post some pictures when I get the parts and install them. Thanks for all the help identifiyin the parts that I had and how was the best way to proceed.