new or rebuild sixpack?

[jordan]

Hi Guys.  I never got my carbs rebuilt.  I decided to race motorcycles instead so all my spare money goes to that for now.  Chryco is right though, I do have a mechanical set up, with the sliding metal linkage.  I have springs, but do not know exactly what they are.  My plan was to get the carbs rebuilt since they are in horrible shape, and then use my Proform jet plates from my vacuum carbs so I have a good starting point.  But now I am not so sure that will work looking at the carbs and the way they bowl is off to the left side.  Sorry I dont have the experience you are looking for.  I am hoping to retire in four years and plan on re-doing a bunch of things on the car,including the carbs to make it more responsive and controllable when the secondaries open up since I like road racing so much.  The vacuum carbs are more of an open/closed system with little control when you need to feather in fuel coming out of a corner. 

[moparx5]

 chryo this is the rod set up on mine, sounds like yours is pretty similar
just putting the feelers out there on this matter to see what options other guys are running as linkage
was gonna work with mu machinist friend and see if swivel rod ends and a machined pick up arm would be smoother. that ring pick up link made from the rod just makes me question longevity
also stop by my engine builder who is in his 70s tweeking carbs for years thinks im to rich in center carb causing some of the drivability off a stop and go down a couple jets
hopefully i will find some time to try that

appreciate all the feedback from all

[RUNCHARGER]

You're in luck, that is the correct linkage Holley made for that setup. Do you have a return spring to bring the secondary carbs back or are they just relying on the throttle blade springs to come back?

[moparx5]

there is no spring to return secondary's

[RUNCHARGER]

I would add one, easy to add pulling on that front carb. I wished I was near you, I'd go through those and set them up right for you. These setups are very impressive when setup right.

[jordan]

Can one of you experts on these carbs explain to me how they feel when driving?  Since there is no vacuum to depend on, and the linkage controls the outboard carb throttle plates, then it should be able to be held at any open throttle position and they work seamlessly?  I wont have to floor it to open the outboard secondaries then back off the throttle to control exit speed coming out of a corner?  Basically I am asking if they sort of operate like one carb instead of using the center carb and then opening the outboard by using full throttle.  I really want something that can have a smooth transition onto the throttle as I apply throttle coming out of a corner.  Flooring it to gain control of the outboards is not smooth driving.  I see how the vacuum secondaries work for drag racing, when full throttle is the only option, but road racing take much more finesse of the throttle setting to control traction and chassis balance. 

[RUNCHARGER]

That is how they work and why they are superior to the vacuum setup. It's not all or nothing when they are working correctly.

[jordan]

I have Proform jet plates in my stock vacuum carbs that are set up pretty good.  Can I swap them to the mechanical carbs and expect similar jetting requirements and drive ability?  I know there is much more to setting up carbs, but at least the main jet sizes on all three shouldn't change unless the carbs flow fuel or air differently, right?

[Jim AAR]

I have been running the mechanical outboards on my AAR since the 80`s.

You have the correct linkage for these but you need to change the locks on the secondary rod, the front one should be just short (2mm max) of the rod coming from the center carb (this ensures that the outboards are closed on deceleration so you don`t need another spring to close the out boards.

For the 2nd lock on the rod, you can set it up anywhere depending on when you want the outboards to kick in (I have mine set up to open at about 3000 rpm for city and highway drivability). I can cruise at 60 MPH running only on the center carb otherwise gas mileage is very bad, you can ease into it at that point but it still gives a pretty big kick, plus the sooner you have the outboards opening the more foot pressure you need and it can get tiring holding it like that for long periods.

Also, if you are going to use the original air cleaner base, you will have to modify your fuel lines to drop right at the flare nut otherwise it will hit the bottom of the air cleaner base.

The throttle return spring you are using looks too stiff, i am using the Original Return Spring with the Original Bracket, you can get them at Roseville. It makes the throttle foot pressure required way better and then you will be able to feather it (it`s still going to be stiff) once you get the 2nd lock set up where you want it to start opening.

I am running the Original Jetting on all, works great at 800 ft above sea level here in Manitoba, might be able to tweak it but I`m not racing it so it`s fine for me.

I've never had the vacuum outboards on it (couldn't get them in the 80`s and i bought my AAR in 79 without them)

These carbs work awesome and there is very little set-up or adjusting to get to run great, Idle, Air/Fuel on the Center carb and some choke and fast idle settings, easy peasy.

I just redid all my lines and linkage, here`s some pics.

[moparx5]

thanks Jim that's some good knowledge , makes sense on that forward stop for secondary's and i'll e mail jon at rosevilles  and have him send me that spring ,   

[Chryco Psycho]

I have run into a number of the vacuum 6 packs with the vacuum pots removed & linkages created to force the end carbs open , the problem is there is no accelerator pump on the outboard vacuum carbs so all you get is a big bog when you force them open .... Not cool !