I have a standard inductive type timning light that has worked fine to date. Today I tried to use it on my Mav w/msd box6bmt/blaster coil/and dizzy pn9582- got a very irregular signal and it indicated the timning was set at 0* at idle and only went to 10* at 2500 rpm. Something is very wrong, either my light has taken a dump or I have real ignition issues. The reason I was checking this is the car is breaking down badly @3500 rpms, even in the garage in idle. Kinda the old chicken or the egg thing. Is my lite compatable with this MSD system? or should it be at least?/ Thanks for any opinions.
i think you posted something else about this on another post. did you try diconnecting the box and running it with out it?
no - I've been leary of that to this point as its a blown car and I really know nothing about the set up yet- just learning. I have checked the plugs, wires etc. I'm starting to think the boost retard switch is bad. Are you saying that I can completly disconnect the box all togeather and still get ignition?
it could be the sptings in teh dizzy.. they may have broken.. check the internal parts, see if anything is broken... get another timing light and try that, if they both say the same thing.. it is the igntion
my sons 306 is doing the same thing. we went through everything. only differance is i can time his with the light. but the 3500 dump is there. were not running the rev limit chip, and it had one for 4k when we got the car. didnt notice an issue then. im almost wonderin if the lack of the chip is playing into it.( although you wouldnt think it would, but electronics are funny like that sometimes) waddya got in yours? and im not even sure its the box/dist. as an issue. guy that built the car was not the sharpest pencil in da box,if ya know what i mean. be real interested in seeing whats causing this. im calling msd tomorrow, hopefully they can give me some insight.
I used my inductive light when I ran MSD ignition. It was not an issue. It sounds like a mechanical problem to me. I suppose that distributor doesn't have vacuum advance? If not, then you may need an adjustable light to do it right??? I am not sure though, I have never had a purely mechanical advance. It seems to me that there should be some sort of lockout mechanisim for timing. Did your distributor come with a lockout pin? I believe you pull of the cap, install the pin, pop the cap back on, then time. Do you have the BTM? That may make a difference too. I would check the instruction books of all the parts you have. Dave
i dont know how to check it.. or how to set it.. i took mine to the local speed shop in tucson, townsend's racing... they set it for me to run at 36* at 3000 rpms.. and told me to leave the initial alone. i have done exactly that and it runs awesome
Buddy of mine had the same issue with the MSD 7al2. Granted he was running a Chevy (yeah, I don't know WHY I hang with him!), but he found many issues contributing to the problem. The first was the light he was using. He used my old Sun timing light per MSD, but that didn't fix it. He then put an insulated wire coming from the distributor (purchased from MSD at a cost of $15). He then isolated all the wiring to the box and ran power and ground directly to the battery (like it should have been originally). Then they told him to make sure that he didn't have any open spots on his rpm and timing chips. It seems that you have to have a 0 chip if you leave one blank. He replaced the box with one from a buddy of his. He bought a new coil. He replaced the firewall isolator and coil wire. Anyhow, long story short...still had problems, but it was steadier now and didn't bounce around as much. In the end his biggest problem was the distributor gear. Turns out he had used an iron gear on a billet roller cam. A big no-no as it ate the gear after only 10 passes (should have used a bronze or composite gear). He tore the motor down and rebearinged it and replaced the gear (which oddly enough only ate 5 of the 12 or so teeth). I guess what I'm saying here is to check and double check everything...even the things you wouldn't expect! The timing light doesn't lie. Anyway those are some of the things he tried...please keep us updated and good luck!
Disconnect the boost retard box and see if that is it. You can download all instruction's and wiring from MSD sight.
bad miss Thanks guys for the suggestions- spent a little more time with MSD tech line today. I have checked the alt output/plugs/plug wires/ pushrods and springs/ moved/changed the position of the wires to both the dizzy and the coil/ bought a new high dollar battery/ checked all the gounds I can find and made sure the hot and ground wires to the box were connected directly to the battery. Tech says to start looking for RF interference from either the elec fan or fuel pump or other source, says the ignition signal is getting distorted or broken up by an outside source, maybe even the alt itself. I'm a little stumped here as a week before, this thing was running like a raped ape. We did some work on the stereo , so I'm going to see if a speaker wire or antenna wire is near the box wire and maybe thats doing it. Very wierd.....
I never did recieve the pictures. Did you pull the dist, Some people like to use a brass gear on the dist. shaft, They wear at a alarming rate, with timing changing all the time, Once they get slack they will start jumping around at idle. Most brass gears i have dealt with would only last 5000 or less street miles. ( then you have all that brass floating around in the motor). Next thing on msd dist., the flyweights are bad about rusting up, hince no advance. Take the BTM out of the system, See if timing comes back. ( I have seen more than one BTM cause trouble) Hope this will give some ideas,
