[Whytim05]

Chasing some info or advice! I have been using the 8360 MSD ready to run distributor with a SS blaster coil in a mild 350 chev. It seems to run fine but once revving past 5000rpm it starts breaking down and mis firing... I dis assembled the distributor to see that the module had burnt out. This has now happened twice... I have been advised to consider changing the ignition set which will consist of running the MSD 85551 distributor with a 6al MSD ignition box and a blaster 3 coil... Any advise would be appreciated...

[eloc431962]

How long has the 8360 MSD been in it ? sounds to me like it's time to up-grade.IMHO




Cole

[Whytim05]

I'm thinking so too. The 8360 would have to be @ least 6 years old. My guess is that it may not be the right application to get high revs without wanting to break down. It's the 2nd time it's happened so I've bitten the bullet and decide to replace it..... Any recommendations be idea what I've already noted above would be great!

[Irelands child]

I suggest one of the MSD Pro Billet distributors and a 6A or 6AL box. If you do go with one the small diameter versions, make sure you have the best possible plug wires or with the Cap-Adapt using that large diameter cap as with mine on my Ford, I found evidence of cross fire even with new Taylor Spiral Pro wires.

[Whytim05]

I'm thinking so too. The 8360 would have to be @ least 6 years old. My guess is that it may not be the right application to get high revs without wanting to break down. It's the 2nd time it's happened so I've bitten the bullet and decide to replace it..... Any recommendations be idea what I've already noted above would be great!

[malc]

I just bought and installed a new 6A digital box.
I made a mistake in that they are so big to find a suitable
place in the engine bay.
If you decide to buy an MSD box check out,MSD Ignition 5520 - MSD Street Fire CD Ignitions
it´s a tad smaller and has the rev limiter.

[Irelands child]

Originally Posted by malc

I just bought and installed a new 6A digital box.
I made a mistake in that they are so big to find a suitable
place in the engine bay.
If you decide to buy an MSD box check out,MSD Ignition 5520 - MSD Street Fire CD Ignitions
it´s a tad smaller and has the rev limiter.

At least the new 6A boxes have a much better wiring arrangement - but you are correct about the size - a big mutha



Dave W

[Whytim05]

Thanks for the replies. While I've been waiting for the new gear to arrive I've had someone repair the module so I had it as a spare if ever required it for a backup plan. I put it back in the motor and had in running again. Within a few minutes it was mis firing again and ended up losing spark upon further inspection. I disassembled the distributor to inspect any further visual damage. All seems to look fine but I've noticed the magnetic pickup is touching 3 of the 8 pickup fins... I'm guessing the contact would cause the mis fire and possible module damage... I'm upgrading anyway but wanting to get to the bottom of the issues I'm having.... Curious to know if anyone else has had this problem. Thanks....

[cobalt327]

Originally Posted by Whytim05

Thanks for the replies. While I've been waiting for the new gear to arrive I've had someone repair the module so I had it as a spare if ever required it for a backup plan. I put it back in the motor and had in running again. Within a few minutes it was mis firing again and ended up losing spark upon further inspection. I disassembled the distributor to inspect any further visual damage. All seems to look fine but I've noticed the magnetic pickup is touching 3 of the 8 pickup fins... I'm guessing the contact would cause the mis fire and possible module damage... I'm upgrading anyway but wanting to get to the bottom of the issues I'm having.... Curious to know if anyone else has had this problem. Thanks....

Are the top bushings/bearings too loose, or what? There should be an air gap as you know.

Have you checked the graphite conductor under the coil? They can have too high of a resistance and actually burn themselves up and can- if bad enough- melt the hole where it goes through the cap. You need to remove the coil from the cap to see this (if you have an in-cap coil, that is).

[T-bucket23]

If you are burning out modules I would suspect a wiring or voltage issue. Do you have battery voltage feeding the distributor, are you sure your engine grounds are solid. Low voltage or a bad ground will cause higher current in the module and cause it to heat up, either can also cause a miss at high speed

[Whytim05]

Ive had another look at it. The bushes seem to be ok. It appear that the plate which the magnetic pickup is on is moving upon rev causing it to touch the pickup fins then causing the mis fire... I'm hoping this is actually the problem, I will have a new MSD 85551 and 6AL arrive next week so I'm hoping a whole new set up will sort it all out. I was concerned that it might be something else causing the problem and then damaging the new ignition
going in... Again, thanks for all the input!