SU Carburetor Synchronizing Kit on eBay

[AUSMHLY]

"SU Carburetor sync synchronizing kit."
Thoughts?

This is on Ebay. FYI $98

"This kit makes it a snap to synchronize your carbs without removing air cleaners or ducting. Simply remove the damper caps and install the collars, insert and zero the gages and adjust the airflow with the air adjustment screw so that both (all 4?) carbs read the same.. Instructions will be provided."

https://www.ebay.com/itm/SU-Carbure...179851?hash=item46aee8720b:g:SxgAAOSwSCZbQatk

 

[red57]

Re: SU Carburetor sync synchronizing kit

That's interesting. They are dial indicators with a treaded collar to fit the damper threads. So they measure the height of the pistons inside.

I'm not sure that would automatically correlate to the actual air flow into the engine - eg, if you had different spring pressures from age or whatever, your pistons might ride at different heights when the actual air flow is the same, conversely if you set the pistons at the same height, the airflow may not be the same. OTOH, they may be spot on.

I guess I'm skeptical and would like to hear some real-world experiences/results - would be good to compare the result of these with manometer or unisyn type measurements.

Anyone tried them?

Dave

 

[vette]

Re: SU Carburetor sync synchronizing kit

If the pistons are riding at equal heights then the air flow in each carb is the same, unless the pistons were shaped differently. But I think this tool is a rediculus waist of time. The small wires found in the traditional SU tuning kit do exactly the same thing and are very effective just by observing the position of the wires relative to one another.

 

[Roger]

Re: SU Carburetor sync synchronizing kit

Interesting that they use a Zenith-Stromberg to illustrate SU! Same principle, of course.

 

[tahoe healey]

Re: SU Carburetor sync synchronizing kit

The advantage to the wire type is that you can raise the pistons the 1/32 more accurately than pushing up on that hard to reach pin. Plus it is dirt cheap as far as Healey tools go.

 

[HealeyRick]

Re: SU Carburetor sync synchronizing kit

But I think this tool is a rediculus waist of time. The small wires found in the traditional SU tuning kit do exactly the same thing and are very effective just by observing the position of the wires relative to one another.

I was thinking the same thing. It might be minutely more accurate than the two wires, but I can't see it making a hugely noticeable difference in tuning.

 

[AUSMHLY]

Re: SU Carburetor sync synchronizing kit

When I saw the ad, I wondered how they worked. I asked the seller if he/she would send me the instructions. Here's the reply.

This video contains the instructions that I send with every SU balancing kit purchase:
https://www.youtube.com/watch?v=3ih5h1J-AN4
These instructions are on a Silver Cloud with HD8's

 

[AUSMHLY]

Re: SU Carburetor sync synchronizing kit

The advantage to the wire type is that you can raise the pistons the 1/32 more accurately than pushing up on that hard to reach pin. Plus it is dirt cheap as far as Healey tools go.

I use both the Uni-syn Synchronizer and wire guides from the SU Tool kit.

One advantage the wire guides provide is you can visually tell if the interconnecting shaft clamp pins are in the same position between the throttle shaft lever slots on both carbs...after you tighten down the clamp nuts. When you first move the control rod to increase the RMP you'll see if the wires go up the same amount.

 

[steveg]

Re: SU Carburetor sync synchronizing kit

I use both the Uni-syn Synchronizer and wire guides from the SU Tool kit.

One advantage the wire guides provide is you can visually tell if the interconnecting shaft clamp pins are in the same position between the throttle shaft lever slots on both carbs...after you tighten down the clamp nuts. When you first move the control rod to increase the RMP you'll see if the wires go up the same amount.

Also the wire guides allow you to sync the carbs with the air cleaners in place. Seems to me the wire guides give you a better analog view (than the dial indicators) if one of the carbs is lagging. You might have the same vacuum at a steady rpm but one carb might lag getting there. Springs or damper oil would need to be looked at in that case.

The wire guides can be free in that you can make your own from coat hanger wire. The kit is $98 and does it really offer a better job tuning?

 

[John Turney]

Re: SU Carburetor sync synchronizing kit

I agree Steve, Rick, vette. A waste of $$.

 

[bob hughes]

You can also use 2 pencils - of equal length of course, works just the same.



Bob

 

[pdplot]

I have a UniSyn. It sits in the toolbox.
I use a stethoscope. Works just as well.
Never had any carburetor trouble in 22 years.

 

[OWD724]

I find the video slightly confusing. As an HD8 is meant to have the butterfly totally closed at idle, with the air being channeled from in front of the butterfly to behind via a small port, which is controlled by the large volume screw. This effectively is the same as the butterfly being slightly open. Thus you do not normally have an idle screw adjustment screw unlike for example an H6 which has a screw to slightly hold open the butterfly. He appears to adjust a volume screw 2 1/2 turns then later talks about idle screw. My description is exactly as it is done on most HD8’s that I know including E types.

 

[Michael Oritt]

You can also use 2 pencils - of equal length of course, works just the same.



Bob

You must allow for periodic sharpening, right?

 

[Dandare]

You must allow for periodic sharpening, right?

Good point.

Danny

 

[bob hughes]

Good point.

Danny

Groan

You are a sharp one down under !



Bob

 

[John Turney]

Watch out, or Basil will have to erase those comments.