Yes they are sintered steel, one common reason for failure is that to remove or install them typically something is pried against the spoke. If it leaves an indents or marks that can provide a starting point for stress fractures. 5M pullies are commonly uses as they have round holes rather than spokes and are not susceptible to fracturing. Gordon on SF made a few utilizing an aftermarket CV which also added a bit of overdrive. our belts have a bit of a unique tooth profile so sourcing something is not the easiest.Can you cnc machine a new billet steel oil pump drive pulley?
Any experience case hardening the teeth profile area for the belt?
Possibly undersized for increasing the oil output?
On the failed part can you tell from the fractured surface what type of material they used for it?
Would love to see the VVT-i happen, that would be awesome!I started building a destroked 7m many years ago. 5m crank and rods, 7m block and head, custom pistons, etc. Would end up about 2.9lt with 85mm bore and 85mm stroke (2jz is 86x86).
Never finished it but probably still have all the bits somewhere.
Not too much been going on with the truck recently. Lots of little jobs. Working on adding A/C at the moment. I've gone to colder plugs again (IQ27) and a bigger water injection nozzle plus more tuning and it is driving so damn well. Really living the new throttle body!
Next big upgrade for the 7m i will be working on when I get time is a vvt-i setup. I've been studying the various Toyota systems and have some ideas on how to adapt them to the old girl but who knows if any of them will work out!