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MG MGB GT V8 Factory Originals Technical - Mallory Distributor - no vacuum pot

I bought my 215 Buick engined MGB as an unfinished project and am mystified by the lack of provision for any vacuum advance in the Mallory distributor. I've no experience of Mallory distributors and I feel that this distributor is not going to work that well for a daily driver as ignition advance will be limited to mechanical only. The sticky i/d label that should on the body of the distributor is lost and there are no ser. numbers on the Mallory trigger module either.

Could this be a distributor for a race or circle track engine only only?
Thanks, Anthony.
Anthony Morgan


The distributor is meant for high performance applications where vacum advance is not important. ( read: your foot is burried in the throtle). It will work fine on a street machine if the curve is adjusted. Gas mileage will suffer. I run one because the Weber sidedraft has no vacum provision. Works well.


About the distributor mentioned above, I didn't mention the fact that it certainly looks like a Mallory Unilite distributor- except for the l. brown cap. I guess it could be used in a marine application too perhaps but what engine would it have been spec'd for in that case then I wonder?

Thanks Pete, what c/r is your engine please?
Regards, Anthony

Sure, Mallory makes a Unilite w/o vacuum advance; I used one on a Chevy 350. And yes, it got bad gas mileage.


Joe Ullman

Thanks for the heads up on the gas mileage with this distributor. I guess I'll be using a stock distributor when I put the engine back in the car- I'm still at college i.e. a limited gas budget.....

I think you can add a vacuum can to most Mallory diss's that don't have one ... see the site and either call or email the proprietor Sam. He seems to know one heck of a lot about Mallorys. I'd keep the Unilite setup if you can; it's pretty darn reliable. In any case, gas mileage with vac advance improves a little but it's nothing to write home about, unless gas prices go way back up.

It needs a slot and a couple of threaded holes in the housing. I'd guess these might have to be added. I special ordered a vacuum dual point years ago and had to wait so long they finally built it using a unilite body. I later added a unilite module (saving about $100 for the assembly as I recall) and still have it. It's pretty tuneable but I've gone to a crank trigger so it's still on a spare engine. You'd also need the vacuum pot and the movable breaker plate which shouldn't be any big deal. The slot could be cut using a drill and a die grinder. I'd say it's worth the trouble.
Jim Blackwood

Thanks Jim, I bought an old Buick distributor on e-Bay yesterday and when it arrives, I'll probably tackle the conversion, using the Mallory parts. I need a vacuum pot on the distributor anyway to get through my emmissions check when I register the car after completing the conversion.

This thread was discussed between 31/12/2001 and 02/01/2002

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