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http://pantera.infopop.cc/eve/...562/m/2241011246/p/8

Look at the last picture. You have to make this bracket.

The throttle cable will then attach to the wheel on the tower.

It will take the place of this long yellow hex rod. I put the rod in the picture to show the orientation of where the cable attaches to on the tower wheel.

There are many variations possible.

The wheel on the tower in my set up is the Mr.Gasket universal pivot. It takes a 1/4"NC hex bolt and there will be two lever arms which it comes with that need to be trimmed down to use inner most mounting holes, i.e., the shortest combination you can make it.

The clearance for the throttle cable is VERY VERY close to the distributor. If you don't put it where my bracket does, you will bind the cable by too tight of a radius turn.

You also need to supplement the throttle springs on the carbs and the cable to insure the throttle wont't bind and will close.

That's why there are two additional Mr.Gasket throttle return springs on my system.

There NEVER was an out of the box throttle kit for this application even from Detomaso. You have to fabricate as best you can.

If you ask 10 different mechanics or engineers you will get 10 different answers. The only thing that won't vary is that the wheel is still and will always be round.

If you are stubborn and want to resist that fact, be my guest, but you will be just spinning your wheels.

My linkage works and stays the way you set it.

The over/under linkage is difficult if you vary in any manner from this design. You will wind up over centering one side of the carbs and you will never be able to sync the carbs at both WOT and idle.

The only way to eliminate that and give you an alternative is to reverse one side of the carbs so that they all face the same way.

If you do that though you will loose a noticeable amount of throttle response right off of idle because the line of sight to the valves is wrong on one side.

It does make the linkage easier to deal with though.

The linkage on the Webers initially is often beyond even a top technitian to deal with unless you have previous experience with it. The Pantera linkage is a little unique. It can be very challenging, specific and even the manifold is designed to handle everything only one way. It is fun for me to make it work though. Others may enjoy it as well? You will need lots of patience with it but once you "get it" it no longer is such a big deal.

A "Weber" 351c set up in another chassis has differences.

It definitely will challenge your understand of geometry. You will now have to match intersecting arcs and lever angle throughout their travel at every point, not just starting and ending points.

It ain't easy pal.

Oh, that silly bracket looks flat in the picture, but it isn't. It needs to be twisted so that the cable is pointing up about 10 degrees or so to clear the reinforcing buttress cast into the manifold. Smiler
Last edited by panteradoug
I think PanteraDoug has some of the best advice here and in previous post.

I would like to post something I am working on. One issue I have with a linear spring is the difficulty in hooking them up...where...they have uniform tension. If they are mostly collapsed on return there is little pressure to hold the throttle plates closed.

This spring pressure in important for Webers. You are essentially using one spring to make sure 4 carbs and 8 throttle plates close and seal. If you don't you will never get your idle down. I know each Weber has it's own spring but it is generally not enough once the mass of linkages are installed.

I am working on trying a recoil spring out of a small engine. I still have the details to work through yet. I think it is going to be more tricky then it seems but I think it has potential of keeping a more uniform spring pressure throughout the movement.






Talk to Comp2. He generally goes on various sabbaticals for weeks at a time but he might already have built what you are looking for?

I forget what you were running for carburetion Chris? A single Holley "variant" I believe right?

Look out for excessive spring pressure on Webers, IR fuel injection and even Holleys. The throttle shafts on original Webers seem like they are made from Silly Putty and twist up very easily.

Put the springs on the linkage down line and not directly of the carb throttle arms.

People are virtually shocked how light the throttle feels on my car. It looks like it is going to be a bear trap but it isn't.
Carbs in general but especially Webers (with 8 throttle plates) need long springs. Long springs have similar pressure at variant throttle positions.

I am not sure what exactly you are looking for but I can speak of how mine has worked.

A lawn mower recoil spring is basically a long spring. I have been extremely happy with the feel. Having said that, with the MG I had a lousy feel to the Lokar throttle linkage. Once I changed to a heavier cable it all felt so much better so a good cable is important too.

Mine is not as elegant as others or even as elegant as it could be but it is extremely functional. Bolting to the actual carbs the way I did had another purpose. This is the Ford 400 engine which is a Cleveland with an extra inch of deck height. The heads were further apart. I used a Hal intake but I cut a center section out and split the intake. The spring plate was just an added stabilized support for the Webers. I probably don't need it but I did it that way because I could.

So a question...Maybe PD can answer this, if you track a car typically don't they require more then one return spring?



quote:
Originally posted by comp2:

So a question...Maybe PD can answer this, if you track a car typically don't they require more then one return spring?



Yes the tech inspectors require two return springs.

On mine, I use the original throttle cable which has a built in spring, each Weber carb has one built in to it, and I have the Moroso unit (which most are familiar with already) attached to the bell crank on the center tower.

That is the dual spring attached to the floating chromed bracket attached to the arm on the universal.
Last edited by panteradoug

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