Balancing Act

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Rudy van Daalen Wetters
Posts: 1206
Joined: Thu Jan 22, 2004 5:53 pm

Balancing Act

Post by Rudy van Daalen Wetters » Sun May 08, 2005 9:58 pm

It was a GTE kind of day, so I decided to try to balance the carbs on my car. I managed to get them all nice and even at idle and the car ran smooth. At 2000 RPM however, the readings are off significantly and I get some backfiring in the exhaust now. Is my next step to loosen the clamp on the trailing throttle shaft and try adjusting the setting there? Timing is correct and compression is even. Any words of wisdom from someone who has done this before?

Thanks,

Rudy van Daalen Wetters
1963 GTE s/n 4001
1966 330 GT s/n 8705

daffy
Posts: 116
Joined: Thu May 13, 2004 12:42 pm
Location: Norway
Contact:

Weber tuning

Post by daffy » Mon May 09, 2005 3:10 pm

Since the Weber`s are pretty alike you can download how to tune them from:
www.superformance.co.uk/

Good luck

Dag
330 GT 2+2 Serie II VIN 8495, 1966
Fiat DINO Coupe 246, 1971
Fiat Ritmo Abarth 1988
ISO Milano Diva 1959
Audi Urquattro 1984
Jeep Grand Cherokee SRT8, 2006

grahamdelooze
Posts: 58
Joined: Mon Nov 01, 2004 4:21 pm
Location: England

Post by grahamdelooze » Mon May 09, 2005 5:25 pm

its possible to have everything looking good at idle but still be in a mess.first you have to sincronize both chokes in each carb under fast idle.best to disconnect the links of the two carbs your not playing with so you can load up the carb you are.this is done with the throtle stops backed off and slackening the brass clamp on the sincro gears.next with all three linkages disconected bring up the throttle stop screws to an idle with all six chokes balanced.now connect the linkage for carb three adjusting without bringing the chokes off their stops.do same with carbs one and two but balance between carbs with a fair pull on the throtle cable so you can compensate for slop in the linkages.dont over compensate or carbs will be off the stops and will spoil idle.all six chokes should now be balanced at idle and under load on the linkages.did mine with a period balancing instument bought off ebay.now you set the idle mixture.
330 GT 6159

Rudy van Daalen Wetters
Posts: 1206
Joined: Thu Jan 22, 2004 5:53 pm

Post by Rudy van Daalen Wetters » Tue May 17, 2005 9:38 pm

Thanks for the advice guys. It sure took time and patience, but all worth while. The carbs are all pulling even at idle and at 3000 RPM. Since my wife's patience was limited with keeping the RPMs up, I rigged a prop rod up between the driver seat and the accelerator pedal which worked well. It is important that the linkages are adjusted evenly with not even the slightest hint of play, yet without effecting the idle position. This takes time! Also, make sure that the linkages are exactly parallel to the side of the carburetor. One of mine was off slightly which affects the arc of the pull on the throttle spindle. You will have less travel through the arc if the linkage is askew, resulting in less throttle opening during higher speed operation. My carb flow meter (synchrometer) is made by STE in Germany. I highly recommend this unit as it is outstanding and well made.


Rudy van Daalen Wetters
1963 GTE s/n 4001
1966 330 GT s/n 8705

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