Should I dump the 3 carb set up?

[kspageddie]

I have been doing some thinking ( I know, it can be dangerous ). I currently have a 3 one barrel set up using Autolite 1100 carbs. I am thinking about using just a single 2 barrel. The main reason for this would be for the ease of tuning. I am not much of a carb guy. All my experience is in 5.0 Mustangs and I am finding that the 3 carb set up is a bear to get tuned.

The 3 hole set up was done by the previous owner and I don't believe that he really had the thing running well. And to be honest the only reason I would stay with the 3 carb set up is for looks, it does really look cool. But is it the best thing for performance?

So, should I jump ship on the 3 carbs and go to a 2 barrel? If I did I would just make some aluminum block of plates for the end carbs ( I really do not want to change the head ). What do you guys think? If it were your motor what would you do?

 

[Anonymous]

Personally i would investigate a little more on the set-up.A few alterations would probally help you a lot

A--First disconnect (or remove and plug intake with expandable freeze plugs) the outboard carbs completely and get it running perfect on just the center carb. Then address the outboard carbs.
B--change to a true progressive linkage--simply make the outboard carb linkage arms shorter than the center carb. This can be done fairly easy Change your center arm to a longer one and then drill several holes in the outboard arms for adjustment ease. Stack them on top of each other clamp them and drill both at the same time. The outboard carbs need to remain closed completely till you hit kick in position(generally around 1/2 throttle) and all 3 become WOT at the same time, accomplished by the leverage factor of unequal arm length..
C--remove the chokes on the outboard carbs completely or at least wire them open
D-- use the outboard carbs as nothing more than a secondary set-up. Properly set-up acceleration can be very rewarding. If you are still setup as your picture shows you are not taking advantage of the rewards but suffering from the complications.


I run 3 carbs on a homemade set up and i can tell when i am starting to bump the outboards by the increased spring pressure on the pedal. My set-up is much more complicated then yours. The biggest trick to tuning is making sure the outboards are behaveing identically --mostly that they are closeing completely and starting to open at exactly the same time. When i start to bring them into use and have them opening their accelerator pumps while the center carb is about 5/8 open the pull is amazeing. Once they are correct use double nuts everywhere so they can't readjust theirselves. The idle air adjust on the outboard carbs are of very little consequence as the only time they are in operation the accelerator pumps are squirting anyways and since the whole engine is sucking from a common intake log I just picked a likely number of turns, set both to that and forgot about them There is a small amount of air/fuel going by even a fully closed butterfly so don't lean them out completely and when you hook them up your idle speed will likely increase a good bit. Don't give up before the miracle happens. Most of my adjustments were made with the engine off, looking down the carb throats.
Good Luck Dan

 

[MustangSix]

Looks can be important, but driveability is nice, too. Why not have both since you have the three carb setup already?

Swap the center carb for a 2bbl. Block off the outer carbs. Retain the linkage. Looks good, runs good, easier to tune.

 

[wallaka]

Kind of ricey though, don't you think?

 

[MustangSix]

Kind of ricey though, don't you think?

Only if you replace the fuel lines with neon lights.... Hey, you'll have to block the old carb openings with something!

 

[saltwaterfalcon1960]

That`s what I would do.Block off outer carbs with thin metal plate and run on center carb.No one will ever know and you will still have the cool look.

 

[kspageddie]

Thanks for the advise. I am going to try one more time to get the carbs to work. If not I just may add a two barrel carb and block off the other ones. The more I think about it, I like that idea. No one would know but you guys and you would not rat me out would you?

 

[Anonymous]

Thanks for the advise. I am going to try one more time to get the carbs to work. If not I just may add a two barrel carb and block off the other ones. The more I think about it, I like that idea. No one would know but you guys and you would not rat me out would you?

I actually have that set-up but with the 1bbl's hooked up.

 

[kspageddie]

Thanks for the advise. I am going to try one more time to get the carbs to work. If not I just may add a two barrel carb and block off the other ones. The more I think about it, I like that idea. No one would know but you guys and you would not rat me out would you?

I actually have that set-up but with the 1bbl's hooked up.

What carb are you using for the center?

 

[Anonymous]

I use an autolite 108
http://i31.photobucket.com/albums/c362/ ... C-030F.jpg
Like i said this is a pretty complicated set-up. I drove for a couple hundred miles with the webers off and got everything else working really well before i put them on and tweaked them in. My only problem is getting the occasional bit of trash in the center carb that clogs up the jet causing really poor performance. The 108 is an excellant carb for a 200, throttle response is crisp and was good for 5,000rpm with no problem. A smaller carb is really good for low end pull I wouldn't want anything larger with a multi carb set-up- as a matter of fact i would try a smaller 2bbl if i could find one(autolite 102) at the right price.
With the 3 carbs though 4,000-6,500 rpm is phenominal. And if you want to smoke the tires it'll make short life of them. Once you get those 1 bbl's kicked in with the tires broke loose nobody believes it's a six.

 

[kspageddie]

danwagon: I am not familiar with the Autolite 108. Is that a size of the Autolite 2100 2 barrel?


It is warm in Columbus today so I am going to work on the carbs when I get home. I need to get the linkage on the center carb figured out. The center carb does not close all the way. Hopefully, I can get it all worked out. I will update everyone tonite.

 

[t-west]

IIRC, 1.08 is one of the venturi sizes of the Autolite, the one that is often recommended for our motors.

 

[addo]

You don't see a lot of XK-E owners giving up on their tri-carb sets. I reckon it just needs some thought, some tinkering and fine tuning. Hang in there; the diagnostic skills will stand you in good stead through the time of ownership.

Cheers, Adam.

 

[Javabean]

I'd vote for sticking with it.....still nothing more impressive than a solid tuned tri carb. You're already over half way there having it setup and all the carbs. Now it's just a matter of will and patience. You gotta figure swapping to a 2V setup is going to cost you something. No offense meant here, I don't know your abilities. But as a thought, it might be worth finding a speed shop or good mechanic and invest those funds in some assistance.

Jay

 

[JackFish]

I wish I had two more carbs on mine to tinker with!
Does anyone know if you can run a tri-carb setup with a cable throttle that comes across the top of the engine? Seems like the only way to do it is with the mechanical linkage?

 

[kspageddie]

Thanks for the feedback. I am going to stick with the 3 carbs. I messed with it last nite and I feel that I am closing in on it...

Thanks for all your input. Everyone is right, I have gone to far to give up now...

 

[CobraSix]

Once you get the 3x1 set up running, it can be fun. Trick is the initial set up.

Performance wise...

http://www.kastang.net/ozversusoffy.html

Slade