Installing the Pertronix MR-183

My instructions above were to ensure that the rotor was lining up with the posts in the slave distributor. To change the relative timing you need to adjust the position of the sensors on the plate by filing the holes and moving them (as suggested previously.)

 

I am considering installing the Pertronix MR-183 in my dual distributor 1979 Dino (USA model). However, when I check the Summit Racing site, it states the kit is NOT compatible with a 1979 Ferrari 308 (neither GT4 nor GTB). Is the website wrong, or is there something different about the 1979 year?

 

Summit says it doesn't fit my 1975 either, but it works.

 

One thing that can confuse this issue is that the MR-183 can not provide both R1 and R2 functionality -- it can only do an R1 only system. So to get ticky-tack (and maintain strict US emission legality), it can't be used on US version carbed 308. Maybe they are stating that it can't be used just to CYA -- just a thought...

 

Oh that makes sense. I am not too worried about the R2 system, I guess I'll keep the original points on a shelf anyway

 

The MR-183 has a CARB executive order permitting installation on most if not all dual distributor carbed 308s. I have one installed on my 1978 GTS US and getting it through smog is no problem. It is entirely legal. As mentioned it has no idle retard capability due to lack of R1 - R2 points but the only problem I have with it is getting the idle low enough due to more initial timing. I had problems with it initially due to installation problems (my fault) but Pertronix was very responsive and helped and now it is sweet. I run Pertronix coils (although you really don't need to) along with Iridium plugs, Accel 8mm plug wires (with RFI suppression) and low (no) resistance plug extenders. It starts and runs great, has never fouled a plug, passed Calif smog check and is averaging about 16 mpg combined driving and I drive it hard. As an additional bonus the tach works as before. The factory points and coils work Ok but I used to foul a plug every now and then. (long down hill runs using engine braking and old style plugs.) and had to reset the dwell every 6 months or so (I ran the R! points with three springs). I haven't touched the Pertornix setup for over a year now. In my opinion the Pertronix is better than the factory setup as the spark is noticeably stronger and it never goes out of adjustment.

Barry

 

Thanks Barry for sharing your experience. Interesting you were having to reset the dwell so often. My 308 is running great - not perfectly smooth but full of piss and vinegar. I suspect the advance may be slightly out-of-spec on the rear bank as the headers and exhaust get pretty hot back there (timing advance sticking?). Could also be points or dwell I suppose. I checked the timing and the advance looked smoother on the front bank so I'm thinking I'll setup the Pertronix in the front distributor to utilize the forward advance mechanism. Just seems like a sensible and more economic option - rather than removing the advances for full service, plus changing points, setting dwell etc. I also like the idea of a single advance mechanism. I'll will try greasing the rear advance mechanism before I buy the Pertronix.

 

Another possible advantage to the Pertronix is it uses only one dizzy for the modules which means the ignition advance to both banks is also controlled by the same dizzy insuring both banks have exactly the same total advance and rate of advance. I set mine to 34 degrees at 5K and let the static at idle fall where it may. Somewhere in the neiborhood of 5 to 8 degrees BTDC. As noted there is the possibility of the modules not being phased correctly but I checked mine and they're right on the money. The reason I had to adjust the dwell was the three spring R! points (two springs is stock.. Back in the day I ran it to 7800 or so RPM a lot and felt I was getting point bounce. No such problems with the Pertronix.

Barry