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useless carb balance tool

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H

Hoghead

Jedi Trainee
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I bought a STE snail type SU carb balance tool and unless I am missing something it is useless on a big Healey as when the device is stuck in the carb throat, the scale is impossible to see being under the fender

80.00 well wasted, or is there some extension solution using a moulded hose?
 
I started with a unisyn and removed the small flow meter that came on it and added a hose and a much larger and remote flowmeter. The secret to these flow meters is keeping them vertical which is hard to do with the unisyn as produced but easy with a hose and a remote meter. I hang the meter from the bonnet and then I'm free to move the unisyn base back and forth from carb to carb as much as I need without disturbing the vertical orientation of the meter (I run triples)
IMG_0457.jpg
IMG_0458.jpg

I don't know what a unisyn costs these days but a flow meter like the one shown is around $20-30.
Dave
 
Sorry about your $80 but you can feel good knowing that you've saved me and a few others $80.
I use the "SU tuning tool", stuck in the damper tube for balancing my carbs, the carbs are after all flow measuring devices. I made the tools out of a couple of writing pen barrels with some bent wire glued in the ends. Seems to work well enough, costs nothing and saves me skinning my knuckles getting the air filter on the rear carb off.

AJ
 
mgtf328 said:
Sorry about your $80 but you can feel good knowing that you've saved me and a few others $80.
I use the "SU tuning tool", stuck in the damper tube for balancing my carbs, the carbs are after all flow measuring devices. I made the tools out of a couple of writing pen barrels with some bent wire glued in the ends. Seems to work well enough, costs nothing and saves me skinning my knuckles getting the air filter on the rear carb off.
AJ
Click to expand...

Yup

My friend had a go setting mine up after my rebuild with a couple of pencils down the damper tubes and a some pencil marks - me - I use a piece of rubber tubing and my ear.

:cheers:

Bob
 
Yes, but you have to take the rear filter off to do that and getting it back on is a nightmare. If anyone knows an easy way to do it I'd be greatful!
I could never tell the difference doing it by ear anyway just as I can't get the knack of using the lifting pin to check the mixture. I always end up raising it too high and almost stalling the thing.

AJ
 
Hoghead,

The snail balancer is actually brilliant in my opinion and money well spent. In particular if you have not had years of experience balancing multiple SU carbs. I have a BJ7 and the tool is incredibly accurate albeit as you say, awkward to use unless.... I used a mirror on an expandable rod (most of us have one) for a while and was able to read the gauge. Then I went to an auto parts store and got a top radiator hose with a 90 degree elbow which fitted snug into the snail, with this I can easily read the gauge between the two SU's.

I have been tuning my car for over 20 years and tools have ranged from a piece of garden hose and coat hanger wires in the dash pots tops, to a Gunston colour tune and a unisyn with the tube and orange bead. While my carbs are fairly well synchronised and tuned (I thought for fifteen years), a friend gave me a snail flowmeter when he sold his car and I gave it a try just for fun. Amazingly, I found the STE snail to be the best of all the tools and I would now give everything else up if I had to choose just one tool. If I tune with all the other gadgets and get them as best I can (including by ear), I then put the snail in the inlet and even the very minor gauge differences can be seen. I can tune to get the exact same readings easily and my carbs have never been happier. Even one eighth of a turn on the screw will change the reading by a very visible amount.

The only tools I use now (for around 5 years) and I believe the most effective for me are the STE snail and the rod/wires which go in the dashpot (they come in the blue plastic sleeve tool kit).

I'm sure many will not agree and at the end of the day it is all individual choice, I just wanted to give a plug for the poor old snail.

Cheers
Tony
 
I am assuming that the tool in question is similar to Moss 375-324 and here https://www.amazon.com/Carburetor-Synchrometer-Weber-Dellorto-Mukuni/dp/B00SLH03R4

For the past 46 years, I have been using a very old Sun exhaust gas analyzer to set the mixture and a Unisyn gauge to set the balance. The tube pivots on the Unisyn tool to keep it vertical if one desires, so I don’t understand the need for the separate hose as red57 described. I don’t understand the need for the tube to be vertical either since all that is being measured is a relative vacuum.

I am not sure how important the goal of perfectly balanced carburetors is on a big Healey since the 6-port intake manifold is not internally divided and the accuracy of the origin hose-in-your-ear method was adequate when the cars were manufactured.

For that matter, how perfect do they need balanced on any British car running SUs?

For the rear air cleaner, I have a 1/2" open end wrench which I have cut down to a length that assists in access to the bolts.
 
This is the tool I find impossible to use. I can see that it would be great, but on a big Healey, it is buried under the fender and impossible to read.
Off to see if I can find a rad hose extension and/or mirror on a stick


375-324_1.jpg
 
I use a Uni-Syn and tilt the vertical tube back a bit so it fits under the shroud. We're not measuring absolute flow, just getting both/3 carbs to flow the same at a given throttle setting, so whatever error there is will be the same on all carbs.

Balancing at idle is not sufficient, either; you have to check them at some off-idle speed as well.
 
Hoghead,

The tool you provided in the picture is the one I use.

I agree with Ron in that "perfect" tune and balance may not be necessary or have a huge effect, however it is nice to know it can be done, and I love the challenge.

To get over the air filter removal issue, I use the rounded RAMFLO filters (not original I know but better than original in terms of functionality) which have a wire clip which is easy to remove the mesh and foam and leave the base plate/dish in place. Taking my air filters off to tune takes 30 seconds and is as quick to re-install.

Cheers
Tony
 
I agree with Tony, this is the best flowmeter I know of for balancing the carbs. I have HS6's on my BJ8, and don't have a problem....get creative with a mirror, or elbows...they sell them to work with this meter. It quantifies the flow too, which is handy for measuring flow through the radiator to compare fan performance.
 
i wonder if some shop-vac fittings would be the right size to make this work better. Lowes has a variety i think.
 
If you set the lift on the butterflies using a 1.5 thou feeler gauge and then make sure both throttles open together, you don't need a flowmeter. These cars set to the book fairley easily unless they've got hot cams when tickover will be uneven.
 
Set it by ear and it runs great.
80.00 well wasted for me, although some have more patience and/or flexibility than I to make this tool work
 
I was unable to get the "snail" to work with my horizontal carbs & DMD manifold. After reading the Des Hammill book, I ordered the Gunson CarBalancer on eBay.
It has a clip to hold the scale vertically; the stopper is adjustable for airflow:
screenshot.994.jpg
screenshot.996.jpg
screenshot.995.jpg
 
You will love it - same result as my home made set up I referred to above which was also inspired by Des Hammill's book. Makes it so much easier to get them even - both idle and off idle
 
Behold, the simple manometer!

Invented__on purpose__by Otton von Guerick in the 17th Century to prove his experiments with vacuum.

PROOF, that one needn't rush out to buy the latest 21st Century tools to work on an old Healey!

With a some variation in where I pick up the vacuum pulse signals, it's the method I use to balance the Weber throttles too. It is also how I set up and calibrated countless numbers of gas-fired industrial burners and other types of pressure and flow instrumentation devices when I worked as a systems integration tech in Lafayette, Louisiana during the 80s-90s.

ct3.jpg


ct2.jpg


Though these are weighted to represent Mercury (MMHg) they are in fact stainless steel rods; they can't spill OR get blown across the control room when hit with too much pressure__true story; beware of "stuck" pressure regulators...). Nor can liquid Mercury (or water) get sucked into a running engine!
 
Randy - If one were interested in adapting SUs for manometer use, would the holes for the connection stubs be outboard of the butterfly, inboard or riding on top as the rear carb vacuum pickup is?

Addendum: video below answers question - it has to be on the engine side of the butterfly.

Some folks make manometers out of bottles:
 
Last edited:
steveg said:
Randy - If one were interested in adapting SUs for manometer use, would the holes for the connection stubs be outboard of the butterfly, inboard or riding on top as the rear carb vacuum pickup is?

Addendum: video below answers question - it has to be on the engine side of the butterfly.

Some folks make manometers out of bottles:
https://youtu.be/7D_f05_a74Y
Click to expand...
+1 :cheers:
 
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