I need the vacuum advance for a 1976 Camaro 250/I6 3-Speed Manual. O'Reilly and AutoZone both list for automatic transmissions. Classic Industries shows the DV1836 and says nothing about the transmission. AutoZone says the DV1836 is for automatic. Why?

 

I did not look into the number but you would want a vacuum advance on any street car that used a normal RPM range. I do not think GM made a car without Vacuum advance since WW2. Maybe since both manual and automatics in 76 where 3 speeds they are not calling them out differently? Even my 1972 2 speed had a vacuum advance. You are safe using a Vacuum advance from a manual car to an automatic car. I have two small block Distibutors in my garage as backs/spares I have no idea if they came off a manual or an automatic. If I really wanted to tweak the time curve the vacuum advance is adjustable. You use a 3/32 hex key in the vacuum port to make adjustments.

Your car should have both vacuum and mechanical advances. An engine idles better with little to no advance. If you add a load or increase RPMs the engine needs spark advance, it will add power. Your vacuum advance will give you more power under load and your mechanical advance works off RPMS.

The only cars I know of that do not really need a Vacuum advance is pure race cars with ridicules stall speed converters. Or guys that dump the clutch at 4000 RPMs on a manual. The circle track car I built had no vacuum or mechanical advance at all. It was locked down and I set it between 34 and 36 edges depending on the heat/humidity on any given race night.

 

There were a few in the 1960's high performance applications that had Delco Remy manual advance dual point distributers.
Not that the OP's six banger would have even had one.

 

I'm not sure how but you both misread my question.

I need the vacuum advance for a 1976 Camaro 250/I6 3-Speed Manual. O'Reilly and AutoZone both list for automatic transmissions. Classic Industries shows the DV1836 and says nothing about the transmission. AutoZone says the DV1836 is for automatic. Why?

Gorn, all vacuum advances are not adjustable. Only the aftermarket adjustable ones.

Thanks in advance.

 

I didn't misread anything, I simply replied to Gorn's statement.
As for the auto vs manual it makes no sense they should be the same.
The motor doesn't care if you have a manual or auto trans.
All it does is advance the spark from the start position to the run position.

 

I agree. Which brings up the question “All say for automatic, why?”
I'm going to try one for automatic. My distributor is not listed (1110666 5K27) as well. It’s a 6 cylinder so it desperately needs advance. However, I’m not racing it. So, I think it will be fine. If it were a big block I probably wouldn’t have noticed. I was just curious if anyone knew why they are all marketed as “Automatic”. I guess nobody knows.