I have a lightened aluminium fly on my ST170 it weighs 5.5kg the standard one is 11kg. I understand the benefits etc etc and the results have been great, i can hit 60 in under 7 seconds. I have just fitted my latest addition which are underdrive pulleys. The standard Water pump and Crank pully weight a combined 1.8kg, my alloy replacments combined weight is 600grams. Will this effectively give the same results as losing another kilo of the fly? The pulleys release a garenteed 5bhp due to underdriving the accessories but its the extra acceleration in low gears im interested in
I am yet to drive the car as it is going through a full restoration so will not be tearing up the streets for a couple of months yet