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"Lightweight" Water pump and alternator pulleys:

http://www.unorthodoxracing.com/pulleys ... 48&model=0

Nope didnt even know they existed... A budy of mine who is a machineist is making me a complete set of lightweight/underdrivin pully set alt,water,ps i could have a copy set made

I've never had good luck with lightweight pulleys. If the diameter is the same/oe belt size, I'd buy them. They look good...

Could be nice, anything rotating saves big... Especially internally, but I imagine that belt drive tops even wheels for benefit.

$178 for a water pump pulley? our stock wp pulley's are pretty light as it is I can't see any significant weight loss going to an aluminum unit (maybe like an oz)...I put their crankshaft underdrive pulley on and didn't care for it, I think a light weight flywheel is a better value then the pulleys which is what I'm rocking now.

I've been contemplating a power steering delete, single belt setup. You would just need to modify the water pump pulley, alternator tensioner and trim the timing belt cover a bit...

Wow 2002 member. Welcome back. I agree, where's the gain.

Something I've had in my head (where something important should be, like my girlfriend's birthday) is the idea of clutching pulley(s). If the drive pulley clutched loose under high centrifugal force, it would free up a lot of HP. It would have to be calibrated to re-engage before the car blew up from having the water pump not pumping.

Rick,
I'm close to what you mentioned already... I have a de-powered(seals gutted, not looped) steering rack, an underdrive pulley, and a Fidanza flywheel already. If all goes to plan, I will be building a G4 bottom end as my next project... Talk about a light rotating assembly.

Jesse,
That sounds dangerous, but if you could make it work safely and effectively, I'd be very interested to check it out! I have some ideas that I want to run by you, next time we chat!

fowljesse wrote:Something I've had in my head (where something important should be, like my girlfriend's birthday) is the idea of clutching pulley(s). If the drive pulley clutched loose under high centrifugal force, it would free up a lot of HP. It would have to be calibrated to re-engage before the car blew up from having the water pump not pumping.

why not just go electric at that point then?
http://www.king6fab.com/pumpblockoff.html

I was going to when I was still really gung-ho. Maybe, once I start working on it again, I will! I would love to have motorcycle-revs, just for fun.

Well I know for the B6/BP guys there are a couple complete kits out there that have a reduced in size crank pulley (or under drive pulley) then a little larger alt and water pump pulley to compensate for the reduced crank pulley. There are the light weight pulleys and underdrive pulley, they are not the same.