G
Guest
·I have included a photo of the stock velocity stacks compared to the Factory Pro billet 60mm (45.3 mm ID) units. I have finally finished the molds for the latest custom velocity stacks and will be laying up parts today. I will include photos when they are out of the mold. It is a one piece unit with three stacks that fit into the stock rubber stacks once they are trimmed. This design allows adjusting the stack length longer or shorter, but not individually like the last units did. The center (#2) stack is slightly taller than the outside ones and the left side stack (#1) is slightly smaller diameter.
This design is based on the last few testing sessions - MAYBE they will be even better. Only one way to tell... TEST 'EM.
Notice the curve in the stock rubber stacks and the large taper and bell-mouth. The stock stack tends to have flow issues in the bend. The velocity (manometer tested) in this area is really screwy (a technical term). It also pulses a bit whan tested at higher depressions - this could be the source of the tuning issues at low rpm/low throttle position. Then again, I could be wrong.
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This design is based on the last few testing sessions - MAYBE they will be even better. Only one way to tell... TEST 'EM.
Notice the curve in the stock rubber stacks and the large taper and bell-mouth. The stock stack tends to have flow issues in the bend. The velocity (manometer tested) in this area is really screwy (a technical term). It also pulses a bit whan tested at higher depressions - this could be the source of the tuning issues at low rpm/low throttle position. Then again, I could be wrong.
