Instead of spending $50-$100+ on a "carb sync" tool, you can build your own manometer fairly cheaply. I used vacuum resistors to prevent any accidental intake of the measuring fluid into the throttle bodies. What follows is my version of a cheap manometer:
First you will need:
12 x Wood screws-found in garage
12 x Cable clamps-$2 for 18
4 x 3/16" ID tubing (mine are all 6' in length)$0.25 per foot
4 x 3/16" Vacuum resistors (Dormin 47311)-$2.49ea
2 x Eye hooks-found in garage
1 x 3/16" 4-way "T" connector-$1.99 (Dormin 47361)
1 x Piece of wood (mine is roughly 23" x 3")-found in garage
1 x Tape measure or level-found in garage
1 x Rope/String-found in garage
1 x Sharpie-found in kitchen
1 x Screwdriver-found in garage
1 x Lube oil (I used 3-1 oil)..not pictured..for fittings & tubing-found in garage
1 x Container of light-weight oil for measuring fluid-found in garage
Step 1
Apply a drop or two of oil to the barb on the 4-way and insert into one of your tubes. You should have to twist and push to get it on, if it slides on easily you probably wont get a good seal. I did the to in the middle first and then the outside ones last and had no problems with interference.
Step 2
Mounted the 4-way to the piece of wood (manometer from now on) using cable clamps around the two middle barbs.
Then I proceeded to stabalize each piece of tubing to the manometer again using cable clamps.
I used one clamp for the middle two tubes since they are straight. For the two outside ones I used a clamp to bend the tube back onto the manometer and another to run it parallel to the middle ones.
Step 3
Next I marked out 18 equidistant lines along the manometer as reference marks for syncing. I then lubed and insert the vacuum resistors into two of the tubes.
When doing this step if you used vacuum resistors instead of regular male-male fittings make sure that the metal insert is inside the tubing as you don't want to take the chance of it being sucked into your TB.
Step 4
Finish securing the tubing to the manometer at the top with another cable clamp.
Since my manometer is MDF I turned it over and mounted the 2 x eye hooks on the backside because I don't think they would be secure on the end of the manometer. I then tied one end of the string to each eye hook.
You should now have something like this
Step 5
Measure from the 4-way to 1/3 of your reference marks and multiply this by 4, mine was the 6th mark which is exactly 1 foot from the bottom of the 4-way. On one of your tubes without a resistor-measure from the open end and make a mark (mine is 4' from the open end). Drop the marked tube into your container of (unused) light-weight oil. *Note: some people used colored water which is fine...I just don't want to take the chance of some of it getting sucked into the engine* Suck on the other open tube until your oil reaches the mark on the tube, you will probably still have to plug the other hoses, it is okay to get a little extra but shoot for the mark. Remove marked tube from container and allow the oil to settle down and into the other tubes. While you are waiting insert the final two resistors into the open tubes.
Step 6
After all of the air bubbles have evacuated the oil it should be at the same level in all four tubes. You are now ready to sync your throttle bodies.
Total cost was $19.95+tax, would be less than half if you used regular fitting insted of resistors and auto grade 4 way but I was already saving 60%-80% of the cost of purchasing a manufactured one I can afford to err on the side of caution and spend a few extra bucks to insure no possibility of foreign fluids in my fuel injection system.
First you will need:
12 x Wood screws-found in garage
12 x Cable clamps-$2 for 18
4 x 3/16" ID tubing (mine are all 6' in length)$0.25 per foot
4 x 3/16" Vacuum resistors (Dormin 47311)-$2.49ea
2 x Eye hooks-found in garage
1 x 3/16" 4-way "T" connector-$1.99 (Dormin 47361)
1 x Piece of wood (mine is roughly 23" x 3")-found in garage
1 x Tape measure or level-found in garage
1 x Rope/String-found in garage
1 x Sharpie-found in kitchen
1 x Screwdriver-found in garage
1 x Lube oil (I used 3-1 oil)..not pictured..for fittings & tubing-found in garage
1 x Container of light-weight oil for measuring fluid-found in garage
Step 1
Apply a drop or two of oil to the barb on the 4-way and insert into one of your tubes. You should have to twist and push to get it on, if it slides on easily you probably wont get a good seal. I did the to in the middle first and then the outside ones last and had no problems with interference.
Step 2
Mounted the 4-way to the piece of wood (manometer from now on) using cable clamps around the two middle barbs.
Then I proceeded to stabalize each piece of tubing to the manometer again using cable clamps.
I used one clamp for the middle two tubes since they are straight. For the two outside ones I used a clamp to bend the tube back onto the manometer and another to run it parallel to the middle ones.
Step 3
Next I marked out 18 equidistant lines along the manometer as reference marks for syncing. I then lubed and insert the vacuum resistors into two of the tubes.
When doing this step if you used vacuum resistors instead of regular male-male fittings make sure that the metal insert is inside the tubing as you don't want to take the chance of it being sucked into your TB.
Step 4
Finish securing the tubing to the manometer at the top with another cable clamp.
Since my manometer is MDF I turned it over and mounted the 2 x eye hooks on the backside because I don't think they would be secure on the end of the manometer. I then tied one end of the string to each eye hook.
You should now have something like this
Step 5
Measure from the 4-way to 1/3 of your reference marks and multiply this by 4, mine was the 6th mark which is exactly 1 foot from the bottom of the 4-way. On one of your tubes without a resistor-measure from the open end and make a mark (mine is 4' from the open end). Drop the marked tube into your container of (unused) light-weight oil. *Note: some people used colored water which is fine...I just don't want to take the chance of some of it getting sucked into the engine* Suck on the other open tube until your oil reaches the mark on the tube, you will probably still have to plug the other hoses, it is okay to get a little extra but shoot for the mark. Remove marked tube from container and allow the oil to settle down and into the other tubes. While you are waiting insert the final two resistors into the open tubes.
Step 6
After all of the air bubbles have evacuated the oil it should be at the same level in all four tubes. You are now ready to sync your throttle bodies.
Total cost was $19.95+tax, would be less than half if you used regular fitting insted of resistors and auto grade 4 way but I was already saving 60%-80% of the cost of purchasing a manufactured one I can afford to err on the side of caution and spend a few extra bucks to insure no possibility of foreign fluids in my fuel injection system.
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