Cannon Intake Manifold rod end possible solution

[Zedyone_kenobi]

I have long hated my Cannon manifold that came with my triple weber kit. The three drilled holes for the rod ends do not line up, so I only used two for my set up. I ran like this for a while, see below

well now I have noticed that the precision driveshaft I bought at Mcmastercarr has started to show more slop than it use to. I am applying a load in the worst possible position as I have it mounted now. I really need that third rod end in the middle to react the loads from the return spring and throttle cable. I have given this much thought. The simplest solution would be to just bend the rod end the few thousands of an inch and then install it. Keep this up until I have no binding. But this could be tricky.

today I was about to place an order for a new linkage kit from pierce manifolds that has a 3/8" steel shaft versus the 5/16" shaft that is currently on the car. This added beef would resis deflection even more.

Or, I could try this. I could drill out the middle hole oversize. then install the middle rod end loose in that hole. Adjust the front and rear rod end so that it is level. This would keep the middle rod end just hanging lose in a hole. then I could apply some JB weld to the hole and in a sense it would fix it in the perfect place.

I grow tired of my sticky throttle cable. If I put a super strong spring, the pedal effort gets rediculous, and the shaft flexes far too much. I need to finda way to get that 3rd rod end.

how I wish the supplied shaft that came with my kit that worked with the SU linkage would have not been bent.

[John Coffey]

I would fill the center mounting hole with JB Weld high temp (part number 8265-S) and then drill and tap in the correct location.

[Mike W]

Zedy,

Welcome back!! It's been a while for you but I suspect that new one has been keeping you busy.

In any case I'm surprised that you are having the binding problems that you are. I have pretty much the exact same setup as you and I have had no issues with binding at all. I do not use the middle rod end for the same reason as you - mine did not line up either. I purchased the hardest stainless steel rod I could find from McMaster as well and it has held up with no apparent bending. I do use 2 very light return springs but my pedal response is more than acceptable and not too tight at all. My throttle cable is also in the same position as yours.

Are you sure that the binding is actually being caused by the linkage? One of the things that I found with my webers is that if the nuts which hold the throttle actuators in place are too tight, it will bind at the carb itself. What I ended up doing was loosening them just a bit and then bending over the lock tab on the nuts so they were firmly held in place but not overly tight. This definitely helped. I also found that with use, the linkage throttle arms would "creep" on the rod preventing a full return to idle. No matter how much I tightened them they would always creep with time and use. What i did to solve this was to apply some red loctite to the rod where the throttle arm attaches essentially gluing it to the rod. No more creep and I always return to idle now. I used to always have to "kick" my fuel pedal a bit as I was coming to a stop in order to get it to return properly and now I don't even have to do that.

In any case hope all is well with you and the family and that some of my hints above may help you solve your issue.

Mike.

[Zedyone_kenobi]

Thanks mike

I thought the cable was to blame at first, but I have it set up that at idle the throttle cable is a tiny bit of slack in it, so the return spring only has to overcome the linkage and not the cable. I would love to run a very light return spring. So blipping the throttle would feel more natural. I need an entire day to mess with this.

Speaking of the cable, it feels like it has a LOT of friction in it. I suspect that where the pedal attaches to the cable and pulls through the firewall are not properly lined up giving me more friction than I should have. I will look into that. I will also double check my screws and make sure they are not too tight. You are right, that smooth rod does allow the arms to move a bit Mike.

You would think soembody would make a threaded one by now. Guess I could take a stab at that. But the locktite is a great idea, and I think you mentioned that to me over a beer or two, or three. good times.

Interesting note. I looked at the universal linkage kits for triple DCOE's on Authentic Weber Carbs, Manifolds, Conversion Kits, Accessories and More!. Their kits only come with 2 rod ends. Apparently the quality control at CANNON really sucks. I am going to tackle the linkage all over again sometime in the next week. The weather is perfect for Z's and a few car shows are coming our way. I want to be ready.

[zKars]

Well, couple of options for you.

1. Weld up that out of line hole and re-drill it in the right spot. Yes it means taking the manifold off and having at least the welding done. But its the "right" way. You could also JB and drill/tap the hole back in the right spot too. I just don't like the permanance of the JB'ing the rod end into the hole. Makes taking the linkage apart a real bugger.

2. Or how about this. Get a long 1" x 0.5" aluminum bar to go across the three manifold holes and mount the three rod ends in this new bar. This has two advantages. First it allows you remove the entire linkage for alignment and service anytime you want VERY EASILY, and you get to place the rod ends where you want to best support it based on where you have your carb arms and throttle cable attachment point etc. I have this arrangement and like it very much. I especially like the ability to have the entire linkage on the bench when aligning the three arms to each other and to the bar.

In fact I have a little connector/sync linkage between the front two carbs and only run two rod ends and two carb arms/push rods from a much shorter (and hence stiffer) 3/8 bar. I wish I had a picture handy.

Maybe a comprimise would be to drill the existing hole large enough to accept a threaded bushing, so you glue in the bushing after its centered, but leave the rod end free to thread into the bushing. Could just grind off the sides of 5/16 18 nut to make the bushing.

Many options, more will be suggested I'm sure

[Zedyone_kenobi]

The bar idea is a really, really interesting one! I like the modular nature of it. I would probably take it to a machine shop to get it done exactly how I wanted it. But I will look into that. It opens up so many options for where I can mount things and where I can place return linkages and all.

I smell a project...

[Mike W]

Zedy,

The throttle cable at the gas pedal where it goes through the firewall can absolutely be a source of friction and subsequent binding. I also had this issue when I first installed the lokar cable. Not sure how yours is attached to the pedal but i had to loosen the fitting on my pedal to make sure, especially at full throttle, that the cable was not binding through the firewall. I simply tightened it up one the alignment was correct. I would suggest checking this before anything else as it is an easy, albeit awkward, adjustment.

Mike.

[tlorber]

Stephen,

I don't have triples, so I don't have to deal with this problem, but I understand it-you should definitely have support at the point where the cable is pulling. I'm not sure by how much the hole is misaligned, but if it is only slightly off, you could enlarge the center hole with a die grinder toward the direction that it needs to go-when you have it centered correctly, increase the hole diameter with a larger drill bit, and then tap and use a helicoil so that you can use the same sized heim joint (rod end). You could probably accomplish that without removing the manifold from the car.

[LeonV]

I share a similar disdain to the Cannon manifold. In fact, I was just doing some research today on better manifolds that I can replace it with.

The previous owner of the 45s I got recently had a very interesting modification done to the manifold. He sent it off to a machinist, who welded in new heim joint towers that were in much better alignment when compared to Cannon's effort. However, the owner still reported some throttle return issues, albeit more minor ones. I have a feeling it had to do with throttle arm alignment/creep, but I have yet to check as I need to build the engine first.

[troubledz]

Wow, That is one pretty engine you have there! May I ask where did you get that fuel rail? Could you please let me know where you bought it from or is it custom?

I would really like one of those.

Thanks, Dean

[Zedyone_kenobi]

behold the awesomeness of the kaminari manifold!

behold the arse reaming price off 699!!!

Leon, want to go half-sies

Edited February 28, 2013 by Zedyone_kenobi

[Zedyone_kenobi]

Thanks for the complement on the fuel rail!

it was homemade

i started out with a piece of generic aluminum fuel rail.

drilled and tapped for AN fittings and the fuel pressure gage

brackets were bent on a vice, sanded and painted and drilled from metal scrap