|
|
|
|
|
|
Registered
|
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
__________________
76 911 S White with maroon interior. |
||
|
|
|
|
Author of "101 Projects"
|
If it did it before, and it does it after, then it's not the ignition system.
Which car do you have? -Wayne
__________________
Wayne R. Dempsey, Founder, Pelican Parts Inc., and Author of: 101 Projects for Your BMW 3-Series • 101 Projects for Your Porsche 911 • How to Rebuild & Modify Porsche 911 Engines • 101 Projects for Your Porsche Boxster & Cayman • 101 Projects for Your Porsche 996 / 997 • SPEED READ: Porsche 911 Check out our new site: Dempsey Motorsports |
||
|
|
|
|
Registered
|
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.
__________________
76 911 S White with maroon interior. |
||
|
|
|
|
Registered
|
Verify point gap and timing
|
||
|
|
|
|
Registered
Join Date: Jan 2007
Location: Rogaland - Norway
Posts: 14
|
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
__________________
- 1974 911S 2.7 |
||
|
|
|
|
Registered
Join Date: Mar 2004
Location: North Jersey
Posts: 416
|
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.
__________________
Howard '76 911S '53 Nash (!) '01 Audi TT '82 GPZ-550 |
||
|
|
|
|
|
Registered
Join Date: Jan 2007
Location: Rogaland - Norway
Posts: 14
|
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
__________________
- 1974 911S 2.7 |
||
|
|
|
|
Registered
Join Date: Mar 2004
Location: North Jersey
Posts: 416
|
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.
__________________
Howard '76 911S '53 Nash (!) '01 Audi TT '82 GPZ-550 |
||
|
|
|
|
Registered
Join Date: May 2001
Location: Peoples Republic of Long Beach, NY
Posts: 21,140
|
I use stock plug gaps to limit system electric loading although tuning pro Steve Weiner suggest .040" for best power w/MSD.
__________________
Ronin LB '77 911s 2.7 PMO E 8.5 SSI Monty MSD JPI w x6 |
||
|
|
|
|
Registered
|
distributor lube...
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???
__________________
Warren Hall, Jr. 1973 911S Targa ... 'Annie' 1968 340S Barracuda ... 'Rolling Thunder' |
||
|
|
|
|
Registered
|
Do a search on this, I think you might be able to go slightly larger than .040" with MSD.
__________________
1977 911S Targa 2.7L (CIS) Silver/Black 2012 Infiniti G37X Coupe (AWD) 3.7L Black on Black 1989 modified Scat II HP Hovercraft George, Architect |
||
|
|
|
|
Registered
Join Date: Nov 2004
Location: Greater Metropolitan Nimrod, Oregun
Posts: 10,040
|
Yes - take a look at Steve Weiner's page - Rennsport IIRC.
Warren! Don't say that - you're scaring me.
__________________
"A man with his priorities so far out of whack doesn't deserve such a fine automobile." - Ferris Bueller's Day Off |
||
|
|
|