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Greetings Everyone, I have a GM HEI distributor that came off an Olds 455. I was thinking of using it on my ‘72 350 and so I looked up the number on the distributor (1103324 7G27) and found it listed under ‘79 Pontiac 403. It’s my understanding the 403 used in Pontiac’s is an Olds engine. My question is will this distributor work in my ‘72 Olds 350? And, will it clear the stock air breather? Thanks, Roqetman
Yes, the 403 is an Old motor. Yes this distributor will work in your 350, though it likely won't have the optimum mechanical or vacuum advance curves for your motor. It probably won't clear the stock air cleaner housing. At a minimum you'll need a spacer under the air cleaner. You'll also want to extract that oil pump drive shaft from the distributor drive gear. And unless you install the HEI in exactly the same relationship to the cam as it was in the original motor, those numbers on the cap won't be correct.
I have a ‘77-79 403 HEI distributor on my engine, originally installed in around 1982.
Back then I put in a Moroso HEI advance curve kit as its center bar and weights gave 24 degrees mechanical advance, which was the same as the original points distributor and allowed me to set the initial to the same as the points at 10 degrees.
The only thing I didn’t like was the vacuum advance canister is 24 degrees, which is a bit much. I made an adjustable stop and set it to 10 degrees.
Jump forward 20+ years and I wanted more initial advance to smooth out the idle on a new camshaft. After a LOT of research and trial, I ended back with the original HEI center bar and weights as they gave 18 degrees mechanical advance so I could set the initial to 18 degrees. This has worked extremely well over the past many years.
Last edited by Fun71; October 14th, 2023 at 04:56 PM.
Good eye but there should be one. 1103324 should have a vacuum advance, so it's likely just missing. This is not a CCC distributor. FYI, the 7G27 date code is July 27, 1977. It didn't come from a 1979 motor.
Joe, thanks for the info. I was wondering about the oil pump shaft. I have a 1” spacer I can use to raise the air breather. I found the Pertronix magnet ring had delaminated causing a skip/miss in the engine. Pertronix tech told me they tend to delaminate after 5-7 years. I’d like a permanent solution and thought GM HEI would be a good option but they weren’t used in ‘72. So in order to get the correct mechanical and vacuum advance is there one you would recommend? I usually mark the rotor with the housing and the housing to the engine block so it goes back in exactly where I removed it.
I have a ‘77-79 403 HEI distributor on my engine, originally installed in around 1982.
Back then I put in a Moroso HEI advance curve kit as its center bar and weights gave 24 degrees mechanical advance, which was the same as the original points distributor and allowed me to set the initial to the same as the points at 10 degrees.
The only thing I didn’t like was the vacuum advance canister is 24 degrees, which is a bit much. I made an adjustable stop and set it to 10 degrees.
Jump forward 20+ years and I wanted more initial advance to smooth out the idle on a new camshaft. After a LOT of research and trial, I ended back with the original HEI center bar and weights as they gave 18 degrees mechanical advance so I could set the initial to 18 degrees. This has worked extremely well over the past many years.
I have a detailed list at home in my files of all the part numbers of the center bars and weights for GM distributors. It lists the part number and how much advance each one gives. If I remember I’ll dig it out and share it.
You prompted me to search for the distributor info, and I found a spreadsheet I was using to document the timing changes. Luckily I added the stamping numbers from the weights and center bar.
GM HEI Distributor 1103324
Weights stamped 139
Center bar stamped 446
Matt69Olds, If you have info on ‘72 Olds 350 distributor I would like to know what the original center bar and weights are. I’m only getting about 12 degrees of advance with initial set at 18 for a total of 30 degrees.
There are significant differences between points distributor parts and HEI parts.
From what I remember, the points distributor doesn't have numbers stamped on the weights.
The points distributors do not have a removable center bar - it is welded to the main shaft.
The points distributor mechanical advance is limited by a pin and bushing, whereas the HEI distributor uses the contours of the center bar and weights for the limiter (no pin and bushing).
Make sure your weights can move easily and the nylon bushings are intact.
Right now I’m running the stock distributor with a Pertronix kit. And your right, there are no numbers on the weights and the center bar is welded to the shaft.
There is also some good information on the Team Chevelle forum. Gotta be careful using info on a Chevy group, the distributors turn opposite directions. From what I understand the parts will interchange, they just have to ge installed upside down.
October 14th, 2023, 02:00 PM
