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ThickCobra
05-08-2019, 04:33 PM
Those of you with a 351w stroker, MSD 83541 Ready to Run distributor and Blaster 2 8202 coil. Are you using a balast resister with the coil. If not, you may want to consider it. This weekend, my car stalled in the country as it appears the coil voltage burned a hole in my rotor cap causing it to shut down. It has been suggested to me that I should add a balast resister.

Not sure this is common, just my situation.

FLPBFoot
05-08-2019, 05:00 PM
Interesting. I have all the documentation from MSD for these exact parts on my Blueprint 351W based stroker. The MSD Installation Instructions say to take out any ballast resistor if you are using stock wiring as the voltage to the coil may be below 12 v and this can cause a problem. On new installations they only recommend using a ballast resistor if you are using a points or stock style distributor.

Did it eat the rotor and distributor cap? Maybe something I need to add to my trunk repair kit.

What color is your Roadster? We were coming into Antioch on Saturday and saw a green and white one going South down Rt 83.

Steve

rich grsc
05-08-2019, 06:14 PM
Those of you with a 351w stroker, MSD 83541 Ready to Run distributor and Blaster 2 8202 coil. Are you using a balast resister with the coil. If not, you may want to consider it. This weekend, my car stalled in the country as it appears the coil voltage burned a hole in my rotor cap causing it to shut down. It has been suggested to me that I should add a balast resister.

Not sure this is common, just my situation.

Sorry but that advice is incorrect. As Steve said, the ballast resistor is used on points based distributors, it reduces the pitting and burning of the contacts. Something else is the cause.

skidd
05-08-2019, 06:17 PM
Something sounds suspicious about this. My instincts would say that you had a bad contact at the cap/rotor point that was causing excessive arcing, thus eating the metal at the rotor.
I have an Accel eCore coil (makes 42k volts) driven by a GM 4-pin HEI module with no ballast resistor. The HEI modules have built in dwell control and love low resistance (under 1 ohm) coils.
Only 3k miles so far, but the rotor is still mint.
I'd bet good $$ that the control module in that MSD distributor you have also has built-in dwell control. Especially given it is designed to work with that 8202 coil, which has a 0.7ohm primary resistance.
Ballast resistors main purpose was to reduce wear on the coil (heat due to excessive current), and reduce wear on points. Electronic ignition modules eliminate the wear on points, so you'll only be helping the coil, at the cost of lowering the spark output. Defeating the purpose of that MSD distributor and coil combination.

My 02c... don't put in a ballast resistor. Buy a higher quality rotor and cap, if they exist for that dizzy. Or.. buy spares and keep them in the trunk.

SSNK4US
05-08-2019, 06:31 PM
A ballast resistor limits the current and voltage(usually dropping from 12 to 9) going to the coil to extend the life of the coil and or points if you have them. (Yeah I’m old) You do lose some voltage to the plugs with a resistor. Not much but a little. Back in the day Chrysler products use to bypass the resistor on the start circuit for easier starting. The manufacturer of the coil would be the one who would dictate the use or non use of a resistor. Some are built in or are made good to go without one. As for your cap/rotor that would have done that sooner or later regardless of a resistor. Moisture under the cap, dirt, wear, carbon or maybe not enough spring tension between the two. Lots of possibles but most likely not caused by a ballast resistor.

Just my 2˘

Kurt

Ha ha skidd you beat me to it as I was writing ;)

SSNK4US
05-08-2019, 06:44 PM
PS... I wonder skidd how many people even know what dwell is anymore. I worked at a dealership for 25 years and would ask “certified” techs and even guys coming out of places like UTI etc what dwell was... 99% ok maybe 98% had no clue. Or
why a dual point was better than a single. Then electronic ignition showed up..... pretty much the most dwell you could ever have. Oh yeah don’t forget magnetic pick ups in between the two.... ;)

Kurt

ThickCobra
05-08-2019, 07:08 PM
Very interesting. I have an email into the tech service at MSD to see whether my distributor and coil combination would require a balast resister. I don't want to install one if it's not necessary.

I didn't mention that when it stalled, I found the #5 spark plug wire had fallen off and was resting on the header pipe. Again, I didn't mention this because I didn't think it relevant. Could this have been the culprit?

Steve, it merely left a burn mark on the underside of the rotor cap below the copper conductor...no damage to the distributor cap. An electrician stopped by to see what was going on and suggested that the burn of the plastic allowed an arc of the spark thru the plastic and shorted to the timing advance mechanism. New cap and started right up. I now carry a spare cap and coil in my travel bag.

Also, my car is red and white but you were probably 15 minutes from my place in Wheatland.

Jay

ThickCobra
05-08-2019, 07:11 PM
Oh yeah, I now have 1500 miles on my car.

NAZ
05-08-2019, 07:54 PM
Ballast resistors were required when we used points. When your Blaster II coil is used with a MSD CD ignition box it's fed with more than 520 volts. It was designed to operate at much higher voltage than 14 volts you're feeding it.

ThickCobra
05-08-2019, 08:27 PM
The coil is connected directly to the distributor, and no points. Also, I do not have an MSD 6 or 7 ignition box. My distributor install instructions shows a very simple set up...no resistor. So, must have been triggered by something else.

Btw, I had a tow truck on hold at about 1 hour plus from home. My friend Martin made a parts run to Advanced Auto, and though it was Sunday, they were open till 7. We replaced the suspected parts and I was on my way home. Cheated the "Ride of Shame" scheduler.

Jay

skidd
05-09-2019, 01:00 AM
PS... I wonder skidd how many people even know what dwell is anymore. I worked at a dealership for 25 years and would ask “certified” techs and even guys coming out of places like UTI etc what dwell was... 99% ok maybe 98% had no clue. Or
why a dual point was better than a single. Then electronic ignition showed up..... pretty much the most dwell you could ever have. Oh yeah don’t forget magnetic pick ups in between the two.... ;)

Kurt

Rember these ..
http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0900c152/80/08/33/c2/medium/0900c152800833c2.gif

FLPBFoot
05-09-2019, 07:28 AM
Rember these ..
http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0900c152/80/08/33/c2/medium/0900c152800833c2.gif

Yes some SBC had those and were awesome! You didn't have to take the distributor cap off to make the dwell adjustments. I felt spoiled when a car had a window in the cap.

FLPBFoot
05-09-2019, 07:45 AM
I didn't mention that when it stalled, I found the #5 spark plug wire had fallen off and was resting on the header pipe. Again, I didn't mention this because I didn't think it relevant. Could this have been the culprit?

Steve, it merely left a burn mark on the underside of the rotor cap below the copper conductor...no damage to the distributor cap. An electrician stopped by to see what was going on and suggested that the burn of the plastic allowed an arc of the spark thru the plastic and shorted to the timing advance mechanism. New cap and started right up. I now carry a spare cap and coil in my travel bag

Jay

Jay,

I'm wondering if when the #5 plug wire came off, the coil charge trying to go out that distributor post to the wire had no place to go so it was seeking a path out of the cap. Any dirt or moisture inside the cap could provide a path for this discharge. Once there is an arc track any charge will continue to run down that track. Maybe a possibility?

Sorry Jay, senior moment, yes you've sent me pictures of your car.....yes I know it's red. I should be on the road in gel coat in a few weeks. Just need to put on the windshield and doors. I'll be in touch and we can meet up somewhere.

Steve

mike223
05-09-2019, 07:50 AM
Just as a matter of information - I only buy 8222 "high vibration" coils now.

Had a couple of the 8202s fail over the years and the 8222 seems to be more reliable (never had to replace one).

Jeff Kleiner
05-09-2019, 08:15 AM
Rember these ..
http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0900c152/80/08/33/c2/medium/0900c152800833c2.gif

Remember them? Oh hell yes...thousands of 'em. If I dig deep enough in the shop I can find my flexible hex tool and dwell meter (28-32 degrees, remember?---but you'd set new on the low end so that they'd stay in as they wore). Probably some points and condensers too :)

https://i.ebayimg.com/images/g/lccAAOSwi8dbUeoP/s-l1600.jpg

Cheers,
Jeff

GoDadGo
05-09-2019, 08:49 AM
Dang Jeffski,

How much do you want to sell that sucker for?
I haven't since one of those since the I was 15 or 16 which was 40 years ago.
Heck, every access panel, including my dash and transmission tunnel uses a 1/8" hex head.
Just kidding Jeff but I do admit to having a 1/8" T-Handled that I keep in the car.

Steve

ThickCobra
05-09-2019, 09:56 AM
I received a response from an MSD Performance tech and he confirmed what you all have said. I do not require a balast resister with my MSD ready-to-run distributor.

Thanks.

Itchief
05-09-2019, 09:06 PM
I have to agree with Steve when the plug wire came off the voltage took the lowest resistance path to ground and burned through the rotor cap

The ready to run with a blaster II coil has a very hot spark that will arc quite a distance if you disconnect one of the plug wires the spark will arc to the frame without any problem

Rick

SSNK4US
05-10-2019, 01:01 AM
Yes skidd of course!!!

And OMG Jeff!!!! I have one that looks exactly like that! It’s buried in a box or a drawer somewhere lol
Yes 28-32 degrees LOL!!!! Or 33-37 with a dual point....geeezzzzz I must of sold hundreds of Mallory dual point distributors. And explained how to set them up. Oh those were the days :D

Kurt

ThickCobra
05-10-2019, 06:54 AM
I may have just experienced a situation of Occam's razor in that the simplest explanation was possibly the correct one. A disconnected #5 spark plug wire.

I can live with that. But, I'm still going to carry an extra rotor cap and coil in my travel bag.

Thanks all. Maybe I will see some of you at the upcoming LCS.

Jay

frankb
05-10-2019, 08:17 AM
Jeff...I have one of those, too! And an old set of points laying in the bottom of a tool drawer! Yes, I am one of those "Old Guys" too!:rolleyes:

weendoggy
05-10-2019, 09:05 AM
PS... I wonder skidd how many people even know what dwell is anymore. I worked at a dealership for 25 years and would ask “certified” techs and even guys coming out of places like UTI etc what dwell was... 99% ok maybe 98% had no clue. Or
why a dual point was better than a single. Then electronic ignition showed up..... pretty much the most dwell you could ever have. Oh yeah don’t forget magnetic pick ups in between the two.... ;)

Kurt

More is less and less is more. You'll know what that means. :)

Those UTI folks think it's injector saturation or duty cycle.

Jeff Kleiner
05-10-2019, 09:15 AM
More is less and less is more. You'll know what that means. :)



Yep!

Jeff

Big Blocker
05-10-2019, 10:08 PM
Hey Jeff,

I'll bet you used to charge up capacitors and then toss them at your buddies, yelling, "Catch this . . ."
I know I did . . . Ha-Ha-Ha. Those were the "good ol days".

And YES, I do have one of those flexible "dwell adjusting thing-a-ma-bobs".

Doc

rich grsc
05-11-2019, 08:47 PM
More is less and less is more. You'll know what that means. :)


Yes sure do, some day our knowledge and how we acquired it will be gone.:(

SSNK4US
05-11-2019, 09:06 PM
So true Rich..... and so very sad....,

mike223
05-12-2019, 08:03 AM
some day our knowledge and how we acquired it will be gone.:(



It occurs to me that we won't be nearly as big a loss as the generation (or 2) that engineered the radial aircraft engines of WW2, nuclear devices, mach 2+ aircraft, and put men on the moon with little more than pencil, paper and a slide rule...

And that we'll be replaced by those who mostly use their data processing capabilities to share "likes" + cute kitten videos...


All agreed - sad but true.

rich grsc
05-12-2019, 10:12 AM
It occurs to me that we won't be nearly as big a loss as the generation (or 2) that engineered the radial aircraft engines of WW2, nuclear devices, mach 2+ aircraft, and put men on the moon with little more than pencil, paper and a slide rule...

And that we'll be replaced by those who mostly use their data processing capabilities to share "likes" + cute kitten videos...


All agreed - sad but true.

This is true, and horrify

skidd
05-12-2019, 04:47 PM
I'm happy I know what dwell is and how to set it, but I'm way more happy that I never need to every worry about it every again!! Nore that the points are burning up, or a condenser is dead. Our knowledge won't be missed. Lol. Electronic Ignition FTMFW!!

skidd
05-12-2019, 04:51 PM
Bwahaha! You guys need to see this video of a cat falling off a TV!!!