Originally Posted by
TheStig
Bout to pull the trigger. Working on a college building addition and our break room is right next to the machine shop. The machinist just also happens to endurance race! So he is very car knowledgeable. Said he'll do it for cheap 😁
Seen a few posts where guys have had this done.... anything to look out for? Think I'm gonna just go easy on it and only go down to 68mm
Anyone know a tuner in the Kansas City area?
Thanks
68mm might be OK.
OEM pulley is 74mm.
OEM bearing is 55mm.
depth of grooves is 2.5mm.
wall thickness is therefore.
68mm - 2 x 2.5 mm - 55mm / 2 = 4mm wall thickness less any under cut of which there is at least one.
When going to 65mm the nominal wall is 2.5 mm thick less u/cut. Not good as these fail with expensive damage being done. The C32 pulley has a 2mm deep u/cut, I am not sure about the SRT 6 one.
I would not modify the OEM pulley, it is better to buy a good aftermarket pulley made from steel. Good pulleys have a smaller diameter bearing inside them and use a spacer. Do not buy an aluminum one.