Carb tips continued...

61porsche

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Most everyone has heard of the factory synchronization tool and how it works. I built my own ghetto version to prove I could and you can too.

I gathered up the supplies:

1. suitable base comprised of a spare fence picket cut at 42".

2. 5/16" clear tubing from the depot. It came in a 10' roll for $2.29.

3.Electrical cable staples ( so the tubing wouldn't be pinched)

4. An eye hook at the top of the board for convienient hanging next to the car at eye level in the shed.

5. A yard stick $1.99 from the depot also. Great for the graduations to clearly see what's happening.

6. 2-cycle oil- a pint. The type you use for chainsaws, etc. It's dark red, and heavy. An old wall paper syringe to help get it in the tube. It takes a while to settle

7. Two plastic bowls. Cheap type, in the grocery store. Glad brand IIRC,
48 oz, 1420ml, or 6 cup size. But measure your carb or air cleaner opening and check before buying.( I saved the reciept so the wife wouldn't get the idea that they were for the kitchen)

Trim the bowl bottom an 1/8" less than the diameter so it's snug. In the top make a 1/2" hole in the middle ( no need to take the stud out) and a smaller hole and x cut for the tube to stick in.

Warm up your engine. Put the bowls on ( Might need to use some tape to make sure everything is tight.) Start up.

Watch the fluid in the tubes and the yard stick and be patient to let it settle.

The rest, well you can adjust from there.

Less than $10 bucks US.
 

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I made one of these also, my problem with them is that when you turn the motor on if you have a serious carb imbalance it sucks the fluid out of one side pretty quickly so you have to pay attention to the manometer right away and kill the engine if it starts to pull the fluid into the carb. Otherwise they are great for fine tuning. I also use twin vacuum gauges which can show valve train health.
 
Notice the amount of fluid, length of hose, smaller diameter hose, etc. The fluid is also extremely heavy. I also sized the suction hole based on the weber cups.

I thought it might too; didn't happen.

I was surprised. I've tuned a lot by ear, real manometer ( I have a Porsche one with hardwood and mercury for my solexs), tube, stethescope, etc.

But if you're careful, it can help your car run better.
 
I have long tubes but I think the diameter is too wide which makes the fluid move too quickly. I have since cut the tubes up for use with brake bleeding and other projects so maybe I will try manometer 2.0 sometime. Pic of cool Porsche manometer?

Notice the amount of fluid, length of hose, smaller diameter hose, etc. The fluid is also extremely heavy. I also sized the suction hole based on the weber cups.

I thought it might too; didn't happen.

I was surprised. I've tuned a lot by ear, real manometer ( I have a Porsche one with hardwood and mercury for my solexs), tube, stethescope, etc.

But if you're careful, it can help your car run better.
 
Steve, I'm with you on the out of balance engine sucking the indicator oil too quickly. Really what needs to happen is there should be a restriction in the hose, not just plug it in full diameter. In my case I also use a small (4") vise grip to pinch the hose when starting, then ease it off gradually. If the fluid starts to run away, pinch down on the hose immediately. It's a hassle when the oil runs to one carb, because it introduces all kinds of bubbles that can weird out the reading.

I've used the BMW factory tool, which is very sensitive and only works at idle; I've had and used several Uni-Syn's but sold them all when I got onto this synch method. The tubing method is so simple, quick, inexpensive (big in my book) that it blows all the others into the weeds.

You do have to cut the WalMart bowls carefully to fit the carbs so they don't leak. I made my own fiberglass bowls which worked adequately; I also inherited one molded rubber "real" carb synch bowl which I am holding on to.
 
I just take a piece of fuel line, put one end near my ear and the other end near the carb intake, and listen to the hiss. When the volume of the hiss is the same they are balanced.

I have done this on tripple-SU carbed cars and then rechecked the balance with a Uni-syn. Works great!
 
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