What is the difference in between single and duel carbs? does it give better horsepower and or performance? also can the engine be stock im putting it on an l6 dodge.
On a 6 cyl car you will have more even cylinder distribution with a dual intake with progressive linkage in most cases over a stock intake.Most aftermarket intakes will have a better runner design than stock also.But it does require getting the carbs in sync you can't just bolt em' up and go.
You sure wouldn't want a progressive linkage! Both carbs must move together. It would help a stock engine some at higher RPM, not much at cruise.
In my honest opinion, on a I6, it's mainly just for looks. I mean it could help the performance a little bit but you won't be blowing any doors off. I plan on installing a dual intake on my truck once the motor is dialed in, but I am doing it for the looks and I don't expect it to have more power, just a little more pep.
Wrong. It's the best single improvement you can make on an early inline six. The 1955 HRM article concerning hopping up a 261 proved it on paper. It will do little or nothing from 0-40 mph, but from 40 on up, it makes a noticable difference.
Must be why all the 6 bangers at race tracks from the begining of time have had more than one carb,,,,, for looks
More carbs = more performance especially if you also have more cam, more exhaust, more compression etc. Back in the day it was cheaper to buy a manifold and a second carb, reusing your old carb, than to buy a bigger carb. Once they invented the 4 barrel carb it became the best choice. But dual carbs still look good and perform well if set up correctly.
If and when your single carb becomes a restriction - that means that the amount of air being demanded from the engine can not p*** thru the carburetor - then 2 carbs will eliminate that restriction and result in an increase. An increase only until the next restriction or limitation shows up !!! That could be just slightly beyond the prior restriction or several hundred Rpms later.
In the early 1950's, "California Bill" (Fisher) did extensive Dyno-testing on Chevy sixes. On a baseline of 74 HP stock, he showed an average of 12 HP gain from 2000-4000 RPM, with only a change to a dual carb set-up. That's nearly 15%! Furthermore, Dyno-testing by Frank McGurk, published in May 1953 HRM, showed a similar increase; from a maximum of 64 road HP @ 3000 RPM (stock), to a maximum of 78 HP @ 4000 RPM with only a change to dual carbs. An increase was seen across the range. Better fuel distribution plays a big part, as was mentioned earlier. In addition, many aftermarket manifolds are baffled for greater velocity. More carburetion is just a part of the equation.
Yeah, but those motors had other modifications done to them. I am talking about bolting dual carbs to an otherwise stock I6 with no other modifications.
And that 15% is out the window once it gets to the tires. I am not saying it won't do anything for the I6, but unless the motor is highly modified, it will make a little difference.
Read again. The HRM tests by McGurk were "Road Horsepower" (rear wheel) done on a Clayton ch***is Dyno.
Strait 6's are awesome and we great motor's flathead or otherwise and won alot of race's in several venue's nascar, drag race, etc. etc. hudson's were great. Over all I think I am with 31 Vicky on this like most enthusiast's of our hobby it most likley wont be the last iteration but you gotta start some whee and find what you like/ what works. I say go for it build till your satisfied then drive the door's off it maybe even scare a few v-8 guy's
Each inch of Vacuum restriction you have at WOT and Max Power RPM costs you about 3.3% in power. Without knowing how much of a restriction you have at Max Power you can't say what an airflow increase would do. The other side is distribution, 2 or 3 small carbs on an inline 6 have the potential for better fuel mixture distribution. Properly installed dual carbs on an inline 6 should help power and economy. Now if they duel, that's another matter
Read between the lines of the quotations............."extensive dyno testing"! How many enthusiasts here can afford "extensive dyno testing"? How much percentage increase would one acquire with "extensive dyno testing" with the stock carburetor??? On a otherwise stock engine, if a knowledgeable enthusiast does their homework on carburetor selection and tuning, MAYBE he/she MIGHT pickup 8~10 percent. Taking that a step further, an enthusiast that really understands carburetors MIGHT pickup 10-12 percent. Now to the other side of the coin: just bolt on two carbs that you happen to have under the workbench, and you just might LOSE 20 percent. Read 31Vicki's response about restrictions. Today, MOST add multiple carbs on an inline 6 for looks. Now if one increases the maximum RPM of the engine, or the volumetric efficiency of the engine; dual carbs can be very beneficial. Jon.
Again....wrong. More than one test on early Chevy sixes proved that bolting dual carburetors on an OTHERWISE STOCK ENGINE still resulted in enough of an improvement to make it worthwhile, and I also proved it to myself more than once. Obviously, they have to be two matched and tuned carbs; you can't expect much from bolting on two "anything" carbs that you took off of two different engines, with different main jets, metering rods, etc.
Handing a pair of carburetors dueling pistols is just asking for trouble anyway.....or is that where two guys walk ten paces in opposite directions and then turn and throw carburetors at each other?
One other consideration is the efficiency of the original carburetor. The OP stated he was interested in placing these on a Dodge engine. Lots of Dodge/Plymouth engines in the late 1940's/early 1950's used Carter BBR-1 carburetors. The Carter BBR-1 was horribly inefficient, which Plymouth found out in 1947 when a strike forced them to use a real carburetor (the Carter W-1). The BBR-1 was on the bottom of Carter's carburetor lines. Jon.
Leave us not forget that Chrysler themselves put two carburetors on larger trucks with straight six engines. It is better. If you are a goof, you can make it worse. But the OP here is not a goof.
How about the Hudson Twin H power or the 53/54 vette or the Chryslers? I had two Stromberg 97s on a Nicson dual intake on a bored 270 jimmy & clark headers. I could not keep the carbs from icing up so added a copper tube from the headers to a plate under the carbs .
The Jalopy Journal
