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Tri-Carbs/Manifold arrived today

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Brosky

Brosky

Great Pumpkin
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Next Weds. will be the installation and tweaking day.

Complete start to finish project will go on my website. I ordered these with a new design solid linkage (see 2nd picture), rather than the flex couplers, to take away as much possible sloppiness as possible. I think that it's going to work out fine. /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
Nice! /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Let me see, I have two cars and two additional spare carbs. Yes, I like it!! /bcforum/images/%%GRAEMLIN_URL%%/yesnod.gif

Terry
 
Paul.
That is way too cool. And of course, you're going to get much better gas mileage, wink, wink, nudge, nudge! Does this mean Dale has to now follow suit or are you just trying to stay ahead?
Dave
 
Hey Dad,

Can I have your old set? Crypty needs a set of
twins for the spare parts box in his trunk!

Those are beauties for sure. I'm betting they
are some of Jeff's masterpieces?

Hey, fly David down from Canada- he'll teach you
how to REALLY tune those triples.

d
 
Sweet, Paul.
You should consider using Ratco's cable linkage. Trust me, there is gonna be a lot of slop in the modified original linkage.
 
How is the length compensation of the throttle shafts made between the carbs?
If there is no compensation then the butterflies will wear on their sides...
 
There is a bit of guesswork when setting up this particular tri-carb arrangement. First, two of the carbs are built with extra-long shafts that when set up on the triple manifold, they approximate each other closely. Now, the manifold is a three-part apparatus that is connected to each other with rubber hoses. Hence, you have a certain amount of flexibility here, however unwanted. Meaning, the manifolds are bolted to the head with a certain amount of latitude of fit. And then the carbs are bolted up and linked with either the spring attachments or this tube attachment. The tube attachment would offer zero play or flexibility in the shaft alignment, which might be a good thing. I would suggest putting everything together loosely and then try to "get a feel" for the carb alignment, hoping that the shafts are as close to a straight line as possible, then snug everything down, including the manifolds. It's somewhat of a crapshoot. But I am not sure that unusual wear will occur if set up properly. I've been running mine for 3 years and have no issues.
 
If you're interested in getting rid of slop in the throttle linkage, check out the cable actuated linkage supplied by RATCO. Getting rid of the stock linkage did wonders to my throttle response. BTW, the shafts almost touched between the aft mounted carb and the middle carb on my set up once installed.
 
Hi Paul:

I have this setup on my car. It works very well, although makes synchronizing & tuning the three carbs a bit more work. I find using the "synchrometer" velocity meter rather than the "bouncing pea" thing for balancing the carbs much easier. Not sure what you plan to use for air filters, but I have 3 K&N circular intakes with chrome holders. Looks pretty neat. Let me know if you come accross anything in the installation I can help with.

Rob.
 
Very nice Paul.
The Strombergs would have been my first choice but at the time, I could not find the intake manifolds. I ended up with a set of Dellorto's for my GT6. Having a mark 1 makes life quite difficult. your setup looks awsome.
 
Oh boy, it's going to be hard to keep up with the Brosky's.
 
Woo Hoo! Another Tri-carb 6 joins the fun. /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
Bill, Shawn, Dale & All:

Thanks for the encouragement and compliments. I just got home after another 12 hour day traveling and it was nice to see the responses to my original post.

Here are my thoughts. I (we) have discussed the Ratco linkage in previous threads and I have no doubts that it is a fine quality product. After deciding to go ahead with this project, I spoke to Jeff Palya, the owner and chief rebuilder at PalTech MicroPolishing, LLC (https://www.paltech1.com/)at great length about the potential binding issues that occur, or that can occur with this type of setup.

Jeff felt that the original flex linkage was a major contributor to that issue, so he had a solid linkage designed and I asked him to install it on mine. He also runs this on his own car as a test bed for his work. The second factor that enters in to the equation is the condition of my existing throttle linkage and bushings, which are all new and tight as a drum.

Jeff felt that under the circumstances described, the new solid linkage between the carbs and new throttle bushings in the car, that the Ratco linkage would not be necessary. I did purchase a completely refurbished and powder coated bellcrank/linkage assembly (the one that bolts under the carbs) from Jeff that has all new parts in it, so that will eliminate any sloppy play in the throttle shaft to carb(s) mechanical action.

If, for some unforeseen issue, I have binding problem, I can always add the Ratco setup later. My current twin carb setup is working perfectly and I get a full open throttle upon depressing the pedal to the floor, so I'm not too worried at this point.

Now for the tweaking and technical issues of the installation. Below are the settings as they exist on the carbs, which are now bolted to a piece of plywood to keep everything aligned. There are also instructions on what to do from there, once the carbs are bolted to the head and the actual alignment and tweaking begins.

Remove the assembly from the wood.

Install the assembly to the cylinder head. The intakes will now be aligned.

Check that the carb to carb linkage is aligned. I have the solid couplers loose, tighten once aligned.

I have the idle screws backed out so that the throttle valves are at zero angle. So once you tighten the couplers the carbs will be mechanically synchronized together.

Operate the linkage and make sure that you get a full range of motion from idle to full throttle where the throttle shaft levers all touch the stops at the same time. Adjust if needed.

If the throttle linkage binds or does not return freely then the carb throttle shafts are not aligned and are binding. If you have this situation loosen one carb from the intake manifold and align until all moves freely. Continue until all are aligned.

Connect choke cables, fuel & vacuum lines etc.

Be carefull when pushing the rubber fuel inlet hoses onto the carb inlets. I have seen very small bits of rubber hose get shaved off and make there way into the float valves and cause the valves to hang open.

Install a new fuel filter.

Fill the carb dampers with SU or ZS damper oil .

Set the idle & fast idle to suit your engine.

I have the fuel metering needles set at 1-1/2 turns CCW from full rich. This is about 1/2 of the adjustment range and a little on the rich side. A good starting point for fine tuning the mixture.

Once the engine is warm you can synchronize the carbs, use the brass trim screws to fine adjust.

Show time, Wednesday 9:00AM, Her Majesty's Service, Swansea, MA.
 
Hey Paul:

Man, best wishes for next Wednesday.

You should bring your digital camera with
an empty card. Set the camera to take a video clip.

Take a video of the engine revving with the carbs
installed. Post it on utube or some place.

That would be awesome to see and hear. I have never
seen nor heard another TR6 engine running.

d
 
Dale,

The digital camera is going for sure. I hadn't given much thought to video. Maybe when Kodanja and Harry and I all get together in CT this summer we'll do it then.

That's a bit too long to wait, now that I think of it. Let me work on that.
 
Hey Dale, this video compilation clip doesn't show the engine (its the one in my sig photo), but you can hear the exhaust until the wind noise drowns it out on the on camera mic. It has a couple good 1st and 2nd gear pulls. I hope to get some better audio this summer.

 
For those watching, please note that Shawn does red-line the engine, not once but twice. That car was born to be driven!

I've gotta get me a video of mine doing that same thing soon!!

When I do, I'll ask for instructions on how to post it.
 
Shannon,

This a better shot of the new couplers:
 
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