Just wondering if there is any advantage to getting a Jacobs Pack rather than the cheaper MSD 6. Can the Jacobs be installed like the MSD for direct fire and is it possible to use the stock coils in either case?

 

dlidlfis [sp]
or fcdlfis [sp]
are mush more cost efficient IMHO

 

Most of the guys that are installing a multii spark set up are going with the MSD6 (including myself) - not sure if the xtra $'s would warrrent the Jacob's. There have been a lot of discussions on both including the dual ignitor alternatives - might want to try a search

 

I have all my new ignition parts including the jacobs rotary pac - its going in on monday weather permitting - i'll let you know if I notice anything special.

 

I got a direct fire 6al setup and works good, noticed smoother revability and a smoother powerband...

 

We do know this much at least...




BTW...It is safe to extrapolate those results to your own situation, for a relative estimate.

 

You cant do DLIDFIS with one Jacobs box. I tried and blew mine out. Later I emailed RX7.com and they told me I need one Jacobs box per ignitor, which would be rather expensive. (!) BUT when I had my jacobs on my widebody '80 with the otherwise stock ignition configuration I loved it. it threw so strong a spark that you could hear ir through the dist. cap!

 

just finished putting my rotary pack in - going for a test drive - let you know what I think

 

DO NOT GET JACOBS - we spent all day setting it up as per the directions - we trouble shot different things for about an hour and finally started up the car, everything seemed good so i took it out and it slowly got worse till the car would start and I couldnt get any spark - we tried to set it up different ways and nothing - it made my car run like crap and took away so much - finally i removed it completly and left the new plugs wires and coils in and the difference was amazing - taking it back to the friend of mine I got it from maybe I'll try an msd box later - but my opinion is it wasnt worth the time or the money.

 

I'll never buy Jacobs.

 

lol....you never miss an opportunity...

It prolly just wasn't grounded right and burned itself out...I had the same problems with a Mallory Uni-light conversion for the '68 FBird Coupe the first time I installed it...it ran good and idled, but died a mere hour later on the road...turned out that even thought the unit was grounded, it died because the engine block was not grounded well enough. Once that was done and Mallory sent me a new unit, I never had any troubles with the distributor's new electronic guts. The details are real important for any electronic additions..

 

well it had 2 different grounds which we always made sure were on - the light was always on that the system had power and we kept checking the fuse which never blew - ran fine on my friends 2nd gen my car just wasnt having it.

 

plus the directions they included were horrible and I couldnt find any rotary info on their website or get ahold of any support by phone.

 

Hehe mar3, I was thinking about you when I typed out my post above.

Here's an interesting bit of DLIDFIS trivia. I hooked up three GM HEI ignitors on a 1/8" sheet of aluminum and installed it right behind the grill/headlight area of a 13B powered B2000. I also added a third Diamond (or Bosch whatever) FB style coil. Anyway, I appearantly didn't ground it very well because it would run for a few seconds and then the relay would click off by itself. I removed the relay from the circuit and tried again with the wire from the battery + directly connected to the ignitors. Same thing. I found that jiggling the aluminum plate seemed to help. When we got it home, I installed a wire with some ring terminals from the plate to the screw holding the FB coil holder onto the inner fender. Viola!

I guess the moral of the story is a bad ground didn't kill DLIDFIS, or something.

 

The fuse isn't going to blow on a low/varying voltage power situation, but it eventually kills any electronic ignition component for whatever reason I could only hazard a guess at. Just because the light on the box came on doesn't mean all is well. The Uni-light conversion I did worked fine for a while until an hour later, when it died. Talks on the phone with a Mallory tech support made me look at the way the engine was grounded and then I noticed I only had one measly thin braided copper cable from the firewall to the block. I replaced it with a new one from GM and then added a monster 2 ga. cable using a threaded bracket hole at the front of the block on the driver side (This is the 1968 Pontiac Firebird, remember...) bolting the other end into the frame. I sanded down the areas to the metal before using a variety of washers and bolts to finish the project and waited for the Uni-light unit to come back. Mallory sent it back under warranty for free including a little check to cover my shipping costs (..and you wonder why I'm a life-long fan.. ) and this time around, it didn't experience any failures. I do MSD because they are a hometown company (El Paso, TX) and I do Mallory because of the products and that kind of customer service...I mean, the error was clearly on my part and they still replaced it for free...

 

Do you have to install two different MAD Boxes? One for trailing and leading?