Hot Rods Early 273 LA multi carb intake question.

Hey guys,

I was just wondering if there is such a thing as a triple carb manifold for early LA motors.

I'm trying to find a stock 4 bbl manifold for my 273 formula S motor I'm building for my future roadster.

I was thinking since it's proving difficult to find a stock 4bbl anyway I might try and find something extremely hard/ impossible to find (maybe doesn't even exist),

I know that there is A 6pack set up but I'm finding its only for 340-360 engines.

I know that 4bbl carb would probably perform better but I like the look of twin/triple carbs. Sooo anyway just wondering if they exist.

I will appreciate any help you can give me.

Thanks

 

Only multi carb I saw listed in a probably late 70's vintage catalog. Also some single 4's listed, hi and lo rise, early and late 273.

 

The big block chevy guys have been known to put big port intakes on small port heads and they seem to run ok. Maybe you could do the same thing? as far as I know the only difference between the 273 and 340 intakes is the size of the ports.

 

The later 318 -360 pieces will work but the bolt hole angles are different and would need to be re-machined to match your 273.

- EM

 

I remember when the 273 engine was available in the "Formula S" version and it was mostly all stickers and stripes and not much in the way of performance. Unless you have a real good reason I would try and find a 340 or 360 for the project. More parts are available and a 340 can be a serious runner.

 

Dunno about later, but the Commando 273/235hp in my '64 Valiant weren't no sticker queen. Dual point, solids, AFB, along with a 4sp, all factory. Not bad for 1964 standards. Zippy little knat it was.

 

I drove one of those when it was brand new at the dealership in Las Cruces New Mexico, I thought it ran darn good!!

 

When I was a teenager, I thought my neighbor's 67 GT with the 273 4bbl and 4 speed ran good...until I put a 396 in my pickup

 

C'mon Jim, you're talkin' apples & watermelons here....

A few years later, I acquired one of them 396ers myself, I do know of what you speak.

 

Commando 273 also had an interesting single plane manifold from the factory.
http://i727.photobucket.com/albums/ww275/66fs/273intakes001.jpg
Looks to provide better hood clearance than some.
http://i727.photobucket.com/albums/ww275/66fs/273intakes006.jpg

Discussion of use with port sizes on larger engines here -
http://www.forabodiesonly.com/mopar/showthread.php?t=140213

 

That single plane is the type that was on my neighbor's Dart...cute little thing.

 

I have a early 273 motor with later heads on it running a Edelbrock 4 BBL intake, seems to run without any issues.

 

The real difference with the early 273 and the later 273 and 318 is in the intake area. the early 273 had 5/16" bolts the later had 3/8" bolts. There is also a different manifold angle so the manifolds will not directly interchange. The later 273 and the LA 318, 340, and the 360 all use the 3/8" bolts and the same manifold angles, although the port size in the 340 and 360 are larger.

 

Formula S came out of the factory with solid lifters, factory 4bbl and high compression heads, so all the work is done already and . In Australia the price difference is very different between 273 and 360. We had a lot of 318 and 273 but few 340 360. I don't really want a race car though, I just want something that does donuts in front of government buildings the extra carbs are more for the aesthetics rather than performance.

 

I was exploring that option. I don't know that I want too much engineering though. My question was more for a bolt on part. But thank you definitely something to consider.

 

Thanks mate. Very good read. I was thinking about something like that duel 4 and putting an adaptor onto it. But I thought that was little lame. You never know maybe I'll dig up a super rare triple 94 manifold haha

 

Thanks mate. Very good read. I was thinking about something like that duel 4 and putting an adaptor onto it. But I thought that was little lame. You never know maybe I'll dig up a super rare triple 94 manifold haha

 

When reworking my 273, the machine shop guy said, that I could run 340 heads on my 273 but, I would have to cut a relief for the larger valves at the top edge of the cylinders. Never took the time to look into it and didn't want to spend the extra money for a set of 340 heads (that's if I could find them).

 

@llonning is right on the money, if you have the factory 4bbl intake it may be your best bet! What year 273 is it?

 

Its a long shot but maybe you can find something new @ exiter auto Dmarv here in the HAMB as I recall owns it. They are selling all the offy repop stuff and maybe they are making the early LA stuff that you require.

Here is his website if a search doesn't work for you pick up the phone and do it the 20th century way.

www.exeterautosupply.com

 

It's a '65

 

Thanks mate I might send them an email.

 

Thanks it looks like they might have something I can use

 

They will probably not have a problem shipping to you, if they don't want to ship to you, they can ship to me and i'll ship to you.

 

...there is always a container headed South....

 

What about 318 heads and matching manifold? I think they are making aftermarket heads for the 318 in Aus and they are not expensive. Saw this in some magazine but don't remember the details.

 

Haha you're probably right but the heads I have are factory high comp heads with o/s valves. I think it's cooler to have a OEM hi-Po setup.

 

What a deal! Haha