pinging issue

[high perf mopar]

I'd be inclined to get rid of the vac advance. Makes there a potential
for problems with a race type engine.

In fact, vac advance adds about 50 degrees advance to an engines timing when cruising.  If you floor it, and the vac advance does
not retard timing fast enough, you will definitely ping with all that advance still in there. I think vacuum advance can be adjusted to
go away faster.

i had this one setup to add only about 8 degree's total..but what i was told as soon as u open the throttle blades ALL vacuum advance stops!!it doesn't....after reading someone else's exp with the manifold vacuum with a gauge hooked up to it,they had to have there foot way into the gas to reduce the timing,,but not all..

i set it up like i had it b-4,,that workd,,but this cam makes highr cylinder pressure compared to the other old school comp solid lifter unit,,as msd's pamplet says then u need less timing..

so,,,today i unhooked the vacuum hose and tried it again down the freeway,without changing anything else,,,much better now!even after pulling over and advanceing the timing some.didn't seem to bother it..its still there barely,,randomly.vacuum advance unit flutter??.. even at higher speeds..

off freeway all but gone..now im out of time b-cause im entered into the capitola hot rods at the beach saturday morning..so,,i will put a few gallons of race gas into the tank for good measure and go from there..

next week i will use the supplied msd vacuum advance lockout and recurve to make sure the vacuum unit wont surge/move like i think its doing now, ... temperamental race engine..thanks for all the input

[cudabob496]

these are really handy! got the little knob right near the gear shifter.

http://www.summitracing.com/parts/msd-8680

[high perf mopar]

these are really handy! got the little knob right near the gear shifter.

http://www.summitracing.com/parts/msd-8680

interesting,,,spark retard at your finger tips,,,can u dial out a ping issue?does it actually work?im in the ball park now,,was just looking at 1/4" 2300 Holley Riser Phenolic Insulator.shaker will be close to the hood..motor seems to generate alot of heat now..power,,,

whats your experiance?,thanks. 

[high perf mopar]

these are really handy! got the little knob right near the gear shifter.

http://www.summitracing.com/parts/msd-8680

do u have to do anything to the distributor?lock it out?make it so theres no advance in it at all?or is it just an electronic thing?

im already running the billit dist and msd 6al box.. 

[Chryco Psycho]

glad you found most of the problem , spacers would help 1/4" should fit OK .

[cudabob496]

do u have to do anything to the distributor?lock it out?make it so theres no advance in it at all?or is it just an electronic thing?

im already running the billit dist and msd 6al box..

no, just hook up some wires! see below:

http://static.summitracing.com/global/images/instructions/msd-8782_frm11958.pdf

The section on cutting a wire on the timing control box was a little confusing, as after talking to an MSD guy, I had to cut one wire, or the car would not fire up.
But I bought the thing a long time ago. Hopefully they have corrected that. Just beware.

[high perf mopar]

no, just hook up some wires! see below:

http://static.summitracing.com/global/images/instructions/msd-8782_frm11958.pdf

The section on cutting a wire on the timing control box was a little confusing, as after talking to an MSD guy, I had to cut one wire, or the car would not fire up.
But I bought the thing a long time ago. Hopefully they have corrected that. Just beware.

after looking at  the new wiring diagram it looks like the old setup u have to cut wires,,new stuff just wire it in,,,,made 4 8 cylinder motors,,looks like its made for my app....thanks...

[high perf mopar]

glad you found most of the problem , spacers would help 1/4" should fit OK .

i noticed today after pulling it into the garage for more tuning it would start dieseling when shut off,,,and then after starting major hesitation when trying to rev the motor,,like there was no pump shot,,,,gas boiling in the carb?until the electric pump would overcome it?after 2-3 short pumps the motor starting reving correctly...

the radiant heat from the motor is alot more than before but the water temp says o.k.180...i think that now the motor pushes alot more power the stock 3 core style radiator is maxed out...hopefully i will be o.k. on saturday when in line to park the car in capitola without a heating problem...after that the spacers and spark control will be installed...

600+ horses=====heat.as long as i can still run pump gas,i will deal with it....thanks.

[cudabob496]

i noticed today after pulling it into the garage for more tuning it would start dieseling when shut off,,,and then after starting major hesitation when trying to rev the motor,,like there was no pump shot,,,,gas boiling in the carb?until the electric pump would overcome it?after 2-3 short pumps the motor starting reving correctly...

the radiant heat from the motor is alot more than before but the water temp says o.k.180...i think that now the motor pushes alot more power the stock 3 core style radiator is maxed out...hopefully i will be o.k. on saturday when in line to park the car in capitola without a heating problem...after that the spacers and spark control will be installed...

600+ horses=====heat.as long as i can still run pump gas,i will deal with it....thanks.

dieseling is due to too much advance, and too much advance will cause overheating

[Chryco Psycho]

or too high idle speed thus the idle solinoid to drop the throttle close when the key is shut off or lean mix

[mopar jack]

Without  the idle soleniod, on hot days I turn the car off while it is in drive. Puts enough load on the motor that it won't diesel which is embarasing when you pull into a show and happens.

[cudabob496]

Without  the idle soleniod, on hot days I turn the car off while it is in drive. Puts enough load on the motor that it won't diesel which is embarasing when you pull into a show and happens.

whats your idle timing setting?

[high perf mopar]

o.k. got off work a little early today and tuned some more,,retarded the timing a couple degree's and installed a 20 degree stop bushing(20 degree's intial) and liter springs in the dist to make up for the lazy throttle retarding the timing does,,no vacuum advance.

also had no choice but to use the outboards some for idle speed,tried to have all 3 the same,,,,without using them the ctr carb butterflys were open quite abit,,probably contributing to the dieseling..idles at 1200,,drops to 900 in gear,,,

all my cars i have to shut off in gear to help prevent dieseling,,unlike yesterday even in reverse it didn.t matter,,so i think until the adj timing setup shows up unless something else pops up it will stay this way for now..

[high perf mopar]

installed the MSD adj timing control today,,have not retimed the motor after installation to set it in the middle of the dial..installed it per instructions set the dial all the way clockwise..i think it advanced it appx 2 degree's this way,,end of dial reads 15 but it will go appx 2 degree's past,,2 degree's advanced,from what its set at now..based upon the grad dial,..it doesn't stop at the 15 mark.

OH YEAH,upon dialing it back the motor slows down,retarding the timing,      way down depending on how far i turn it..motor coughed back very slightly upon starting based upon there guidelines,,they probably meant to set it on 15..

i think my slight pinging/det problem on the freeway is now gone...mounted it on the console plate right behind the shifter.at my finger tips..snaking that cable under the carpet was alot of fun...will wrap the wires tomorrow and continue on with the carb fuel line insulation and phenolic spacers..thanks for the tip cudabob496..

[cudabob496]

installed the MSD adj timing control today,,have not retimed the motor after installation to set it in the middle of the dial..installed it per instructions set the dial all the way clockwise..i think it advanced it appx 2 degree's this way,,end of dial reads 15 but it will go appx 2 degree's past,,2 degree's advanced,from what its set at now..based upon the grad dial,..it doesn't stop at the 15 mark.

OH YEAH,upon dialing it back the motor slows down,retarding the timing,      way down depending on how far i turn it..motor coughed back very slightly upon starting based upon there guidelines,,they probably meant to set it on 15..

i think my slight pinging/det problem on the freeway is now gone...mounted it on the console plate right behind the shifter.at my finger tips..snaking that cable under the carpet was alot of fun...will wrap the wires tomorrow and continue on with the carb fuel line insulation and phenolic spacers..thanks for the tip cudabob496..

Cool, ya, adjustable timing for $150 is well worth it!  Only thing I saw someone doing wrong was retarding it way back each time for starting purposes. Then the person wondered why it was not functioning one day. MSD told him it was not designed to undergo major adjustments every day. I checked my idle before I installed the MSD unit, then installed the unit with the dial at 7, then moved the distributor to get the same idle. That way I was fairly sure that I had the same idle after installation.  Cool thing is you can increase advance until pinging, then back off a tad, and you should be running at max power for the gas you have,and the temp outside, etc.