okay, american v8 gearheads, i need some help

[EtaSport]

Aside from my e30, I have a 49 chevrolet with a built 327. Its running around 450-475 hp. forged crank, 11.25 comp pistons, double hump gm performance heads, dual valve springs, 1.6 roller rockers, torker intake and 750 holley. heads are ported/polished, the whole nine yards, oh yea and the nessesary cam thats way too big for the motor. Something like .550 lift. Anyway, for years we've been running an accel dual points distributor that required an msd ignition just to idle because the spark was so weak. It has no advance at all so I was running around 30 degrees advance at all engine speeds. I recently got an HEI unit on ebay. The distributor was tested and worked well, but when i installed, i didnt have any spark.

It is a one wire hook-up with a tach output signal. I wired one 12 volt from the ignition and checked the voltage all the way to the connector (12 volts). Why dont I have any spark? What can i check on the distributor? could the module be bad? could it be a connector problem? I am almost at a wits end because I'm not sure why it worked before and not now. If anyone out there can help me out a bit, I would appreciate it. I was going to have a shop hook it up to their distributor machine but they want like 40 bucks just to check. I have to talk to one of my buddies at the local shop to see if they can test it also. Otherwise I may be able to trace it myself, but if anyone can help it would be great.

[Cre8tivPro]

Re: okay, american v8 gearheads, i need some help

Aside from my e30, I have a 49 chevrolet with a built 327. Its running around 450-475 hp. forged crank, 11.25 comp pistons, double hump gm performance heads, dual valve springs, 1.6 roller rockers, torker intake and 750 holley. heads are ported/polished, the whole nine yards, oh yea and the nessesary cam thats way too big for the motor. Something like .550 lift. Anyway, for years we've been running an accel dual points distributor that required an msd ignition just to idle because the spark was so weak. It has no advance at all so I was running around 30 degrees advance at all engine speeds. I recently got an HEI unit on ebay. The distributor was tested and worked well, but when i installed, i didnt have any spark.

It is a one wire hook-up with a tach output signal. I wired one 12 volt from the ignition and checked the voltage all the way to the connector (12 volts). Why dont I have any spark? What can i check on the distributor? could the module be bad? could it be a connector problem? I am almost at a wits end because I'm not sure why it worked before and not now. If anyone out there can help me out a bit, I would appreciate it. I was going to have a shop hook it up to their distributor machine but they want like 40 bucks just to check. I have to talk to one of my buddies at the local shop to see if they can test it also. Otherwise I may be able to trace it myself, but if anyone can help it would be great.

the 12volt source must be constant with the key in the "start" and "run" position and you need to remove the ballast resistor you most likely ran "inline" with the point-type setup. You also need to ground the other side of the module. Thus, no spark.
HEI or MSD HEI check here for specifics on wiring.

http://www.msdignition.com/pdf/pn8365.pdf

EDIT: I currently run a complete MSD ignition on my 95 Chevy, rotor, distributor, cap, 8.5 wires, coil, and an MSD 6a ignition box....works and performs awesome

[EtaSport]

Yea, ive got pushbutton and i have a separate switch for ignition on. It constantly feeds power when it is on. And I also did remove that ballast resitor. I mistakingly had it wired up the first time and I thought that was to blame for no spark, but took it out and still nothing.

You mentioned the ground. My dad asked me about that too. I have a harness that comes from under that cap and plugs into the coil, one of the pins says ground on it, but im not sure exactly how that works. The only other two connectors were the battery and the tach. I will look into that connector pin more tomorrow thought. That wiring info looks very helpful. I was wondering if i could wire my msd into the hei, and it may save me if the module is bad, and that page tells me how to do it, so thats great. I will look into this more tomorrow now.

Yea, I wanted to go with like an 8555 mechanical advance disstributor with 6a or the like, but a bit pricey for me and a friend of mine recommended hei.

We have an 88 ford 460 pickup (a little bit of work, lets just say is not smog legal) with an msd pro billet mechanical advance, motorsports 9mm wires, blaster 2, and 6a ignition box. That setup is flawless. thanks again, i'll report back with any new info.

[Cre8tivPro]

Yea, ive got pushbutton and i have a separate switch for ignition on. It constantly feeds power when it is on. And I also did remove that ballast resitor. I mistakingly had it wired up the first time and I thought that was to blame for no spark, but took it out and still nothing.

You mentioned the ground. My dad asked me about that too. I have a harness that comes from under that cap and plugs into the coil, one of the pins says ground on it, but im not sure exactly how that works. The only other two connectors were the battery and the tach. I will look into that connector pin more tomorrow thought. That wiring info looks very helpful. I was wondering if i could wire my msd into the hei, and it may save me if the module is bad, and that page tells me how to do it, so thats great. I will look into this more tomorrow now.

Yea, I wanted to go with like an 8555 mechanical advance disstributor with 6a or the like, but a bit pricey for me and a friend of mine recommended hei.

We have an 88 ford 460 pickup (a little bit of work, lets just say is not smog legal) with an msd pro billet mechanical advance, motorsports 9mm wires, blaster 2, and 6a ignition box. That setup is flawless. thanks again, i'll report back with any new info.

that harness you speak of that connects to the module under the cap does plug into the spot on the cap, and that in turn will connect to the 12volt source, a tach lead, and then the ground. You just run a power wire to switched 12 volts, then connect a ground off the cap to the engine or frame ground. The module's harness uses the power plug to tie into the power sources. If you don't have anything else connected you won't have spark. The terminals farthest out on the plug part of the cap are where you run your power and ground and tach feed. A standard speaker spade terminal will suffice in connecting your leads to the cap. Also if you run a tach off an HEI you'll want to run an inline tach filter or you'll burn up your tach.

[EtaSport]

Alright, this is the dilhema. I only have two leads off the cap to run wires to. They are a 12 volt, and a tach. I dont have a ground connection on that part of the cap.

The harness has a ground labled on it. I traced it to inside the cap where it grounds on the distrbutor housing. I removed the coil and there were also two grounds in there. One from that pin that is connected by the harness, and one from the actual coil. So i have no external ground connection. I have run a series of tests on the unit, and really havent come up any better than where i was before.

All said and done i think either the coil, the module, or the pickup coil are trash. Gee those are all the parts in the distributor. I am going to try to find someone who can test this and tell me exactly what is wrong.

[Cre8tivPro]

Alright, this is the dilhema. I only have two leads off the cap to run wires to. They are a 12 volt, and a tach. I dont have a ground connection on that part of the cap.

The harness has a ground labled on it. I traced it to inside the cap where it grounds on the distrbutor housing. I removed the coil and there were also two grounds in there. One from that pin that is connected by the harness, and one from the actual coil. So i have no external ground connection. I have run a series of tests on the unit, and really havent come up any better than where i was before.

All said and done i think either the coil, the module, or the pickup coil are trash. Gee those are all the parts in the distributor. I am going to try to find someone who can test this and tell me exactly what is wrong.

pull the module and have it tested at any of your chain parts stores like Vato Zone or Pep Boys. You still need an external ground if I think I know what you're talking about. Most cars that come with an HEI already have it built into the harness that plugs into the side. You shoudl have a plug running from the module, that plugs into the cap, and then an external harness that plugs into the cap from the car's main chassis wiring. Test the module though, they are very delicate. Let me know what happens.

[EtaSport]

Well, I got the module tested, and it turned out to be crap. I picked up a new generic one for now since it was 12 bucks with lifetime warrenty. Hooked it up, set the timing and with a twist of the distributor it fired right up. Right now im not running vacuum advance since I dont really need it at the moment, perhaps i will try it out later on. I set the advance around 20 degrees and it seemed to like that. This hei stuff is new to me, so i will have to play with it a bit more. I set my idle around 900 which ive never been able to do before, have instant throttle response and smooth power all the way up to 6 grand which i try to modestly shift at. With my points, it would fall on its face with you hit that gas, and then pop and sputter from around 4k-6500.

I'm real happy with the way it is running now. Thanks for all your help. I think because i forgot and left my ballast resistor hooked up that it might have scrambled the module and i just didnt know it. The guy i bought it from was shocked and told me to send it back to him and he was going to give me one with all brand new parts. I guess I got an honest seller. But im glad that it all worked out.

[Cre8tivPro]

Well, I got the module tested, and it turned out to be crap. I picked up a new generic one for now since it was 12 bucks with lifetime warrenty. Hooked it up, set the timing and with a twist of the distributor it fired right up. Right now im not running vacuum advance since I dont really need it at the moment, perhaps i will try it out later on. I set the advance around 20 degrees and it seemed to like that. This hei stuff is new to me, so i will have to play with it a bit more. I set my idle around 900 which ive never been able to do before, have instant throttle response and smooth power all the way up to 6 grand which i try to modestly shift at. With my points, it would fall on its face with you hit that gas, and then pop and sputter from around 4k-6500.

I'm real happy with the way it is running now. Thanks for all your help. I think because i forgot and left my ballast resistor hooked up that it might have scrambled the module and i just didnt know it. The guy i bought it from was shocked and told me to send it back to him and he was going to give me one with all brand new parts. I guess I got an honest seller. But im glad that it all worked out.

sounds good! glad you got it fired up and running. I'm not sure I helped much except suggesting you get the module tested :) but usually timing works best around where you've got it set, with that high of compression though, might want to back it off a bit before connecting your vaccum advance. good job!