MSD 6al 6425

pmarshallsay · 10-14-2015, 08:37 AM

I am looking for mounting ideas for this unit for my 1979 911SC. I was hoping to mount it in space vacated by old CD box, but it looks way too big to fit. Anyone fitted one of these recently?
Thanks

Ayles · 10-14-2015, 10:15 AM

I put mine there. You can get a mounting kit that stands it off a half inch or so on rubber isolation mounts. I had to relocate the large silver thing... Can't remember what it's called...

bpu699 · 10-14-2015, 11:34 AM

Mounted mine to the firewall...

MSD now makes a much smaller unit, don't recall whats its called ("Atom?"). If I had to do it over I would get the smallest unit they offer and fit it in the original spot...

Bob Kontak · Bob Kontak's Garage

Mounted mine under driver's seat.

Walter_Middie · Walter_Middie's Garage

I'm surprised that more people don't mount the MSD in the original location and the original orientation.

There is interference in the upper forward corner of the MSD and the wheel well. I just mounted a piece of 3/4 inch plywood ( with the upper forward corner cut off) in the stock location, then mounted the MSD to the plywood. It fits perfectly, and looks stock. All it needs is that little bit of clearance to mount in the original location.

mreid · 10-14-2015, 06:06 PM

I mounted two of them there:

fred cook · fred cook's Garage

I put an MSD 6A (same size) in that space. All I had to do is to rotate the rear window defrost relay 90 degrees. Don't forget to put an inline fuse in the power lead!

pmarshallsay · 10-15-2015, 06:36 AM

Thanks guys, this is all a lot of help. Does anyone know what this black box and connector are? I need to move them to make room for the MSD unit. Is it just a different model of defrost relay?
I notice no one here seems to be using an adapter. Everything working OK without?

al lkosmal · 10-15-2015, 06:53 AM

I mounted my MSD-6A in the stock CDI location by making a mounting plate.

regards,
al

PS: The new MSD Streetfire is smaller and mounts there fairly easy, as well.

Ayles · 10-15-2015, 01:08 PM

What do you mean by adapter? I am using a factory style plug that allows the msd box to plug directly into my wiring harness. Once i got the wires figured out it was plug and play.

regency · regency's Garage

here's mine.

1973 911T MFI Coupe, Aubergine

Steve

pmarshallsay · 10-15-2015, 04:06 PM

Ayles - I mean Tachometer Adapter (I have a MSD 8910), recommended for cars with points distributors. I am electronically challenged, so I can't tell you what it does.

fred cook · fred cook's Garage

Quote:

Originally Posted by Ayles

What do you mean by adapter? I am using a factory style plug that allows the msd box to plug directly into my wiring harness. Once i got the wires figured out it was plug and play.

Some Pcars require the use of an adapter for the tach. Note that I said "some". My 1980 SC worked perfectly without needing the tach adapter.

Oops, we were posting at the same time!

pmarshallsay · 10-18-2015, 07:03 AM

Thanks for everyone's help. I think the 6425MSD unit I have is longer than the old 6420. It is 8' x 4", so fitting is very tight. Can someone tell me what this black plastic box located next to CDI is for? If I can relocate this, I may be able to squeeze the MSD unit in.

al lkosmal · 10-18-2015, 07:14 AM

I believe that is your external voltage regulator. However, if you have a later alternator that has an internal regulator....this can be eliminated.

regards,
al

pmarshallsay · 10-18-2015, 07:38 AM

OK that makes sense, thanks. New alternator sounds v expensive. I will find a way to relocate the VR!

Charles Freeborn · Charles Freeborn's Garage

I posted the same question a while back:MSD Location
The "black box" item may be a rev limiting device that'll be N/A with the MSD. That's what it is on my car. And, as said on mine I had to rotate the rear window defogger relay 90º
-C

timmy2 · timmy2's Garage

Black box in your photo is remote voltage regulator, device below it is the noise suppressor unit for it.