Hot Rods Another Distributor Identification Question

Can someone tell me what the GM HEI distributor off an SBC 350 (1975 Chevy truck) is? Here is the code stamped on the side: 1112884 5D18? I'm trying to determine what the vacuum advance is so I can order a new one? Haven't been able to find a distributor locator index that shows this configuration.

Thanks.

 

Vac advance is on the bracket part of the can itself, coded in as a number.

 

Light trucks and passenger car applications have a LOT of vacuum advance as part of coping with EGR. These will ping like crazy at part throttle (remember the 1970's?) if you don't have functioning EGR. I think only short advance factory cans are on big trucks, but aftermarket ones would be easier to find.

 

Thanks, I'll have to pull the cover off and see.

 

I'm at work with no hardware to look at, and My GM memory is faded...I think the can bracket is stamped with last 5 digits of PN and number of degrees in can pull. Also, the aftermarket cans I have noticed generally are stamped with a degree number.

 

While I haven't got the number off the can, I found this table (Ray's Chevy Restoration Site) to potentially use as a guide towards which cannister to use. Irrespective of which can is currently on the dist, not sure what the right choice of vacuum s/b on it. I believe the engine is stock from a 1975 K20 truck. Hoping to put a vacuum gauge on it this weekend.

 

save

 

Hard to find info, glad to get it. More 'classroom time' on the HAMB.
Thanks, guys.

 

5D18 means it was made April 18, 1975. That's a big help, right?

some of you guys need to work on improving your libraries

 

Thanks Jim, that's the info I was looking for!