Which one? There are 5 x distinct HT 350M carbs. Unless you get the right one for your car you might as well fit the HQ carby.

My point was all of the HK through to HQ carbs (until ADR27 compliant engines appeared about 8/73) are the same, only difference being the vacuum source between auto and manual applications.

As a bit of background, we got a US numbered carb supplied to us for GTS327 as it was a 1967 spec carb which was pre-emissions. 1968 spec carbs in the USA went to pollution spec so GMH got their own unique numbers starting around the introduction of the Canadian 327 engine. 702 was 1960's, with 703 being the Californian spec pollution carb up until 1967, then all 702 became pollution spec. When the 1970 model year started the carbs went to 704.

So whilst a late HK through to HG were 7029281, 2, 3 and 4 for respectively 308 manual, 308 auto, 350 manual and 350 auto, the HQ initially were 7041281, 2, 3 and 4. Identical carbs, the 4 instead of 2 meaning 1970's and the 1 instead of the 9 as they were first numbered in 1971 instead of 1969. Back to the point, the only difference between the 350 manual carbs for HQ and HT is the numbers. If you are chasing Concours correctness, the wrong HT carb is no better than a HQ carb as the only difference is the numbers. Of the 5 x different HT carbs, they are all stamped either differently or missing codes or different date codes. So a carby off a late HT GTS350M is wrong in a Concours sense for all of the HT's prior to it and vice versa, and you'll pay in excess of $10k for one as well, so you are best getting the right one, or use a far cheaper wrong one, like use a US 7029213 which you'll pickup for near nothing. Also be careful, someone was stamping blank carb bodies a few years back and you don't want to go paying big bucks for a fake.

Further background, at any given time the same spec/tune carb was used for everything from 240hp 327 to 300hp 350. So the 250hp L73 (GTS327 engine) used the same carb as the 275hp L30 (fuelie headed 327) to the 295/300hp 350 (L48 aka HT-HG GTS350 manual). They just got slightly different numbers depending upon the brand usage (8 in for example 7029283 for GMH in the 60's and earlier 70's), the 702/703/704 variation and the 4th digit for the year of introduction of the carb. There is also some variations in the final digit over and above manual V auto, to do with variations along the way.

Edited by user Wednesday, 21 June 2023 11:29:16 AM(UTC)  | Reason: Not specified

$10-$15k. Just need the right buyer.

Finding a HT-HG GTS350 carby will be your challenge.

It’s a waste getting the wrong one though. Like putting a Dandenong engine in a Pagewood car.

I have since found a HT350 auto carb but it has a 73 date code so im guessing its a service replacement carb. Any thoughts

I would still check the jetting on the carb you end up with. Correct jetting for HT 350 M is main metering rods 45B , main jets 71 and secondary metering rods AN. Thanks Mark.

I seriously doubt its a service carby. GMH got heaps of the engines and carbs prior to the end of HG to send over in the CKD packs for South African SS so any spares were most likely procured then. It is also possible it's a boat carby. GMH were supplying complete 350 engines in the early 70's to Ski Craft, these were later engines but used the HK-HG engine numbers, it is possible the carby is off one of those. From memory all of the boat 308 engines supplied into the later 70's also had auto late HQ / early HJ carbs on them.

Well done. I think there was only 2 x date codes in that format applicable to HT, the 3rd one is HG.

Which date code?

Someone with a HG GTS350 manual will want that, which is where it originally came from.

7028212 is off a 1968 US or Canadian 327/250hp, 327/275hp or 350/295hp automatic car. It is the same spec as the carby that was fitted to 1968 GMH assembled Pontiac or Chevrolet but those had Rochester not Carter Quadrajets.