Spark Plug gap with MSD ignition...
 

Do you guys think that leaving the spark plug gaps at stock would cause a car to hesitate around the 2000-3000 RPM range? I just installed the full msd ignition and it did this with the old ignition but the coil was failing with that set-up. Could my air mixture be off? valves need adjusted? I'm kinda lost now. Maybe I have an intermitant injector? I'm reaching. IT runs ok before 2000 and runs ok at the top end 4000-6000. Not sure what is going on.

Any suggestions?

Thanks,
Jeff

If it did it before, and it does it after, then it's not the ignition system.

Which car do you have?

-Wayne

76 911 S with factory 2.7L. It hesitates worse in second but also does it in the other gears. Fith on the interstate is also bad. IT runs but if you give it gas it hesitates. If you give it gas very slow it will accelerate.

Verify point gap and timing

Have the same problem on my 911s 2.7. Also installed MSD ignition and have the same problems 2000-4000 RPM range. Use stock spark wires at the moment - can this be the problem? Can someone please confirm the right gap for the sparkplugs? Have MSD, Blaster Coil and soon new wires.

Thanks!

/Joachim

I have a stock '76 911S with MSD and Blaster Coil...and no hesitation. I have had issues with the centrifugal advance in the past, and if yours has never been serviced it's about time. I'm using a slightly larger-than-stock plug gap, but I'm sure that's not your problem. Look closely for air leaks from hoses and the intake air box. Do you have a pop-off valve? Check for air leaking around the cement seam. Double check point gap, electrical continuity and timing.

Thanks for answer! I'm not that info the technical stuff... Just bought the car some moths ago... CAn you please provide me with some pictures or something that indicates what to look for...

THanks!

/JOachim

Using this web site's SEARCH function will do you more good than my descriptions. Removal and disassembly of the distributor is not difficult; just be sure that the orientation of the rotor before and after distributor removal is the same, so that timing is not disturbed. Looking for air leaks is just a matter of careful checking, with a mirror if necessary (i.e. the backside of the pop-off valve). Congratulations on your purchase. After you find and cure the hesitation problem, you will enjoy it even more.

I use stock plug gaps to limit system electric loading although tuning pro Steve Weiner suggest .040" for best power w/MSD.

http://forums.pelicanparts.com/showthread.php?s=&threadid=5432&highlight=distribu tor+lube
<b>
Do you suppose all these hesitation problems 2000 - 4000 rpms are just a coincidence ... or, is it because that is where the MSDs failures in the switchover circuit from multi-spark to single spark ocurs???</b>

Do a search on this, I think you might be able to go slightly larger than .040" with MSD.

Yes - take a look at Steve Weiner's page - Rennsport IIRC.


Warren! Don't say that - you're scaring me.