Balancing Throttle Bodies

[spookypt]

Hi all, chasing some advice on balancing throttle bodies. I have that annoying problem with unbalanced bodies where I get the POP POP's out of teh RHS bank (Left pipe) when the car is in cruise mode. Open TB's no probs and idle no probs just cruising is the annoying POP POP. I need a guide or tool that will help me get the TB's perfect.
Often its te linkages but mine are new.. I have tinkerd with this to overcome the problem and all I managed to do was transfer the pop from the LHS bank (RHS exhaust) to the opposing side! Close but not close enough!

I need one of those vacuum gauge type arrangements... Any ideas?????

The GT40 guys (Tim and Paul) have also had this drama with multiple TB's and overcame it with better quality linkages and a a good set up tech!

SpookyPT

[Cameron Parsons]

Ah Mr. Spook... Welcome to my world of fun!!

I had some issues way back and solved them by seeing the guys at Hi Torque in Labrador, Ashley did a very nice job.. They have a rolling dyno and tuned her up nicely. More HP and no pop's. They were also uber careful with tinkering to make sure they didn't damage any of the shiny bits.

I would recommend a visit. Details to you by private email.

Cameron

[Gav]

Spooky,
I use what is called a monometer for measuring very low levels of pressure or vacuum with work.
You can buy a digital one that will be accurate to within .01 of a pascal for about $300 from System Control in Brisbane or Farnell.
However if you don't need to know the measurement but are just interested in ensuring that the vacuum is equal across all 8 trumpets you can make a slack tube monometer from a peice of wood and clear plastic hose.
You will need to fix the hose in a U shape about a meter down then up and fill the U shape portion about half full with water.
By waving the open end of the hose in the mouth of each trumpet, the vacuum will raise or lower the water level in each side if the slack tube. You could note where each is with a texta mark or set them all to one mark.
3/8 tube would work fine.
Give me a ring if need be, 0407 110641

Gav

[bobcowan]

You need a special tool called a synchrometer. Inglese sells them for $65 US. I think I got mine from Mike Forte, but I don't remember what I paid for it. Here's a picture of one, with a cheap price: ACC-C10-7125 - DELUXE CARBURETOR SYNCHROMETER TOOL They can only be used with an air horn.

You could make a manometer like Gav said. But you have to be very carefull about how you use it. If you just wave the hose end around the throat, you'll get a variety of readings. Not very accurate. Maybe if you taped it the inside of one of the horns, and then move the horn around. Then you'de get repeatable result.

[COBRAMAN 484]

TWM has a Synchronizer part# STE-BK for adjusting throttle bodies. They also have one for weber carbs part# STE-SK. They are both $80 American. I have TWM 50 mm throttle bodies on a 484 fe and have been using the STE-BK for about nine years now. they are very easy to use and worth every penny.

COBRAMAN 484

[mr0077]

How about a Uni-Syn?
UNI-SYN CARB SYNC TOOL