Installing an MSD-6AL on my '83 3.0L

[jeffs9146]

Does anyone have any tips or advice on installing the MSD Ignition unit in place of the stock CDI unit on a factory injected '83 911 SC 3.0L?

I am going to attempt this on Tuesday and wanted to get a few tips or tricks before cutting into the harness!

[Bob Kontak]

Hi Jeff,

Leave a little more time than a half day.

You do not have to cut the harness, if I recall. You feed spade connectors into the original CDI harness.

I installed mine under the driver's seat and ran wires through the back firewall using grommets. For me it was more to free up engine room. In a race application I read it can help keeping the box away from heat.

Also grounded the unit to the transmission ground lug. A good ground is very important. These things use juice and need a good ground.

I can post pics if you need but I think once you choose where you are going to place the unit the rest is just which wire goes where and the instructions are pretty straight forward.

There may be a tach adapter issue and I'm not sure if your 83 requires that.

I can help you in any case. It is not a hard installation, it is very tedious and detailed.

Think through where you want to route the wires regardless of box placement. My rear firewall grommet holes could have been thought through a lot better as to stealthiness.

Also, don't gap your plugs to the max. You can open them up a bit and there are plenty of threads to search on, but going too big (0.060")will make it real easy for spark to find an easier ground than the plug.

[LakeCleElum]

When thru this recently when we put a 3.0 (now 3.2) in my 73.5.

2 things to watch for. Ideally you pair it with the MSD Blaster coil. This was a necessity to retain my 73.5 tack, not sure if it's required to keep your tack.

If your current rotor has the fuse-link, replace the rotor with a Napa part # (I can find the # if you need it).

I bought my MSD/Coil used from a Pelican here and it came with the instructions to wire......Didn't run well at all that way. My mech had to think about it overnight, reversed 2 wires and all was good. He said the instructions were for install on an American car.....G'luck

[Joe Bob]

Curious as to why? I've read that there isn't any gain over the Bosch CDI.

[Bob Kontak]

+1 on the Blaster coil.

Joe Bob - I had legacy Permatune(s) and.............

[jeffs9146]

Originally Posted by Bob Kontak

Hi Jeff,

Leave a little more time than a half day.

You do not have to cut the harness, if I recall. You feed spade connectors into the original CDI harness.

I installed mine under the driver's seat and ran wires through the back firewall using grommets. For me it was more to free up engine room. In a race application I read it can help keeping the box away from heat.

Also grounded the unit to the transmission ground lug. A good ground is very important. These things use juice and need a good ground.

I can post pics if you need but I think once you choose where you are going to place the unit the rest is just which wire goes where and the instructions are pretty straight forward.

There may be a tach adapter issue and I'm not sure if your 83 requires that.

I can help you in any case. It is not a hard installation, it is very tedious and detailed.

Think through where you want to route the wires regardless of box placement. My rear firewall grommet holes could have been thought through a lot better as to stealthiness.

Also, don't gap your plugs to the max. You can open them up a bit and there are plenty of threads to search on, but going too big (0.060")will make it real easy for spark to find an easier ground than the plug.

Thanks for the info!

I am currently running W7DSR Bosch plugs which are fairly hot as they are so should I start with the gap at stock or bump the gap 0.02" more?

I have insalled the motor in a 914 so there is a mounting plate hanging off the battery box and the motor was running before the CDI dumped!

So I shouldn't have to do anything to the wiring except jump into the existing harness and ground, right?

[jeffs9146]

Originally Posted by Joe Bob

Curious as to why? I've read that there isn't any gain over the Bosch CDI.

My Bosch took a dump!

[Joe Bob]

Permacrap, Permadoom....take yer pick.

As to the Bosch, 'ischmitz' on this BBS rebuilds them. Ingo has 3 and 6 pins ready to go with a warranty. No need to worry about tach adapters and different coils......just saying.

[MrShades]

I do not use Bosch spark plugs anymore

I used to use Bosch Platinum W 3 DP(high heath)on my 1985 3,3 twin turbo converted Carrera
If i just did some "in the city driving" a spark plug always broke if i did not take the car for a spin for a couple of miles at the highway before parking the car to prevent a spark plug issue

This spring i changed to really cheap(1 Bosch spark plug cost more than i pay for 6 NGK spark plugs)NGK BP 9ES(high heat)and the car is much better at any speeds and if i drive in the city to the supermarket or if i am driving on the highway in high speeds

[Bob Kontak]

Originally Posted by jeffs9146

Thanks for the info!

start with the gap at stock or bump the gap 0.02" more?

So I shouldn't have to do anything to the wiring except jump into the existing harness and ground, right?

DO some searches. I would go five thousandths first then five thousandth increments and check if you have a plug wire light show at night. I remember folks saying 45 thousandths worked for them pretty well.

Don't attack your harness. Correct (from memory). Maybe a splice or two max but no major surgery.

Vincent hill put one in recently and there is some interesting discussion in there. May help with trouble shooting. I am Stuck, Replaced the CDI & Coil & Still No Spark!

[whiteSC]

Fred Cook describes a method that doesn't require cutting the harness in this thread:
MSD 6AL How to wire

[jeffs9146]

Update!!

OK it was way easier than I thought! It took longer to adapt the bracket to hold the larger unit than it took to wire it up!! For $229 it was way cheeper than paying $595 plus $200 core for an original rebuilt!!

It started on the first click.....now it is time to tune the baby and go for a drive!!

Thanks for the basic tips to get my confidence up!!

[Vincent Hill]

Originally Posted by jeffs9146

Update!!

OK it was way easier than I thought! It took longer to adapt the bracket to hold the larger unit than it took to wire it up!! For $229 it was way cheeper than paying $595 plus $200 core for an original rebuilt!!

It started on the first click.....now it is time to tune the baby and go for a drive!!

Thanks for the basic tips to get my confidence up!!

Mine seems to run better and burn the fuel better also!

[mholbrook38]

If your CDI box works, keep it for emergencies. I installed my MSD digital with soft rev limiter in about 3 hours. I used spade connectors and kept the original CDI plug. Had to move my voltage regulator (79SC) to make room for the much larger MSD box. I would never go back.

One note. Be absolutely sure you do not have metal core wires on your car. I used Clewett and they are either the best or very close.