Triple Carb VS direct mount weber

62Cometman

Well-known member
I wanted to ask you guys what you thought would be a better HP producer and triple single carb setup with a offy intake or doing with a direct mount weber, i know the weber would be easier to install and much easier to tune, but i wonder the true performance capabilities of the offy conversion. What do you guys think?
 
With any single center mounted carb, you are going to have fuel distribution related issues.
Also you didn't mention whether you were going with a 32/36 or a 38/38 as your weber of choice.
-ron
 
If I was going to use multiple carbs, I would mill the top of the log for two progressive 2 barrels; one spaced roughly over cylinder two, and the other spaced roughly over cylinder 5.
 
I don't see any helpful literature (flow bench, 1/4 mi time comparisons, etc) on the tri-power (may B some ol mag article?).
There should B lots of info on the Weber(s).
You'd have to do some math, I guess to compare (CFMs comparison) to figure the differences.
Still, every installation might B different (a P'nP, here, none there, different ignitions, etc).
May B post this in the forum for related Qs:

viewforum.php?f=22

Let's C what the more informed have to say...
(y)
 
The money you spend on this deal, you would be better to purchase the CI head or the head Matt has on vintageinlines.com
 
Howdy Cman and all:

For pure HP a triple mounted direct linkage carb system is hard to beat. Of course that is assuming that the rest of the engine is built and tuned to maximize. There are many other factors to consider in this brain game. That's my two cents, for what it is worth.

I saw a 3x1 Falcon at the drag strip outside of Fargo, ND back in the sixties. I don't know what else had been done to the 170, but I do know that the owner had set the linkage to have all three carbs open together. Just from the smell I thought it was running rich off the line, but it hauled. First tri system I had ever seen on a six.

Adios, David
 
I'm planning triple glass bowl 1904 carbs on my 250, but I'm going to make direct mount mods to the log.

The Offy setup seals to the log with o-rings for the front and rear carbs.

Basically going to mill a couple of flats, and build up mounts that will take stock coolant pass thru carb mounts, so I can use stock pivot and and arms, stock linkage to center carb, and progressive linkage to the outers, like the Offy linkage.

Performance wise, I can't say, but I know I don't like the O-ring seals with the Offy adapters.
 
There is a real advantage in the three ports close to intake runners on the tri-power type setups to even fuel distribution. Especially with bigger carbs, the center vs end cyl's get a different fuel mix, I'd like to see an analysis of A/F ratios on different cylinders with big center-mount vs tri-carbs.

As CZLN6 illustrated, the OFFY specific linkage is what I would call infinitely variable. Designed ingeniously with simple rods and slip stops, the Offy linkage can be adjusted from fully synchronous, to variable progressive with two simple adjustments with a screwdriver. Depending on adjustment the progressive linkage can open outer carb throttle plates gradually from just above idle, be set to snap to WOT at a pre-determined position on the center (main) or can open some throttle position in between .

On the '61/250 with a tri-port Offy adaptor I've experimented with many multiple and single carb setups both synchronous and progressive. With a large 2bbl center carb, the outers can open progressively later into throttle position close to WOT with good results. With the classic small outer carbs and slightly bigger (CFM) main/center the outer progressives' can open at any position best for drivability.. I can literally drive the 250 to the speedway with normal tri-power progressive setup and simply re-position two sliders on rods with screwdriver to transform to synchronous operation for the day ...

I also bult a Hi-Rise plenum for a big 2Bbl (500 CFM 4412) to sit on the Tri-Port adaptor. It was infinitely easier to tune , ran great from idle to WOT but wasn't any faster ..









have fun
 
CoupeBoy":20x82bfu said:
About a month ago I bought (3) YF clones off ebay, stored for when I find time for my next project.
I will likely use them on a 250, I've got one sitting on the shop floor.

I was also looking at these the other day wondering if they would work.
maXpeedingrods 44 IDF Carb Carburetor With Air Horn for VW Bug Beetle Fiat Porsche for $100 each it could be a fun time.
6137kCh1VhL._SL1000_.jpg

I'd like to see three of the 44IDF's atop three 2X1 adaptors, on top of an Offy tri-Power manifold , that would look cool ...

haev fun
 
I like the '1 per'.
Try Keihns or Mucuni as in the ford6 thread.

http://www.v-performance.com/products/air_fuel.html
http://www.triumphspitfire.com/carbchoices.html.

http://www.altiss.com/ThrottleBodies.html

http://www.turbosport.co.uk/showthread.php?t=103402

http://www.danstengineering.co.uk/

ttps://www.youtube.com/watch?v=rWM5-xZ1q0M

https://www.youtube.com/watch?v=JIeh3Bf_8sQ

ttps://www.youtube.com/watch?v=YyTHu3NkQIE

https://www.youtube.com/watch?v=1-EVAnY7WKQ


CUT OFF LOG or INTAKE

Sawed off Log

OpelGT+3point3
viewtopic.php?f=1&t=74153&p=570045&hilit=Cutting+off+the+log#p570045

Chopped Log and Intake

viewtopic.php?f=22&t=77786&p=599485#p599485


BTW: the Carter YH side drafts were onda 'vett.
 
Thanks, for all the replies, I was just trying to get a feel for the best way to make the little 170 feel like she was giving it her all, i was also looking for a "easy" install hence the 2 nearly bolt on setups, maybe someday ill finally get around to installing a 200 slap on a aluminum head and really see what the 6 can do but until then i wanted to have a little extra fun without breaking the bank.
 
My tri power does pretty good, I'm happy with it, I'd definitely recommend it. I found my tri power head on here, it was in rough shape, so I got it cheap. Put up a post in the wanted section and see what happens.
 
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