Underdrive pulley set - Perth-WRX.com

Rossco · #1 28-03-2009, 05:12 PM

After having the air bleed nipple on my alloy radiators side tank fracture during last weeks hills run and bodging it to last me through last week, I finally got around to pulling the rad to fix it (1/4 bsp brass barbed fitting tapped in now...all good!).

I figured I'd fit the underdrive pulley set I've had laying around collecting dust for 6 months.

Install went ahead pretty pain free, nice to see whoever made our alternators had some fore thought by providing a means to lock the alternator's rotor to break the pulley nut free.

Crank bolt was a piece of cake with a 24" breaker bar, engine locked by 5th gear.

The belts I bought were spot on (thank god!).

Total time for rad repair / pulley fitment 2.5 hours.....piss easy.

Worst part was bleeding the cooling system again......over an hour!

Car seems to pull a bit better down low off boost, steering has a little more weight to it (what I wanted).

Pretty happy with the whole job.

I suppose it's like removing 2 kg from the flywheel, everything seem a little crisper when driving.

Fun way to spend a saturday arvo!

mattmy99 · #2 28-03-2009, 05:18 PM

Nice work

and they look pretty too.
Unfortunately, i replaced my pulleys with light weight GFB items at the same time as fitting my VF34, and fmic, so it was hard fo me to tell where the improvements were coming from. In saying that, I didn't notice any lag what so ever when i installed my fmic... possibly counteracted by the underdrive pulleys?

Good to hear you're happy with them.

Hurtenstein · #3 28-03-2009, 05:22 PM

Alternators are a bosch unit.

I was messing around with my alternator the other week and found the factory pulley to be really light anyway... Got a rough idea how much lighter the aftermarket one is?

Rossco · #4 28-03-2009, 05:40 PM

The Alternator pulley is smaller than the factory one, you fit it along with the smaller underdrive crank pulley....the alloy one would be lucky to weigh 20 grams!

The idea is that by running a smaller pulley on the alternator you are actually 'gearing' it up so the alt runs at the same speed as before (stops it under charging).

The crank pulley is a full 2.2kg lighter than the oem one, smaller so the A/c and p/s run a little slower (and lower 'geared').

Also gave me the chance to undo all the excess red paint the previous owner decided to use to paint everything he coud unbolt and paint.

Rossco · #5 28-03-2009, 05:45 PM

Quote:

Originally Posted by mattmy99

Nice work

possibly counteracted by the underdrive pulleys?

Probably, mine doesn't seem so lifeless off boost now.

reflexwrx · #6 28-03-2009, 09:10 PM

I always wondered if the pulley kit made a difference. I'm gonna wack a set on now and hope it's worth the dosh. I do like the pretty colours, A little extra bling in the engine bay never hurt anyone.

Rossco · #7 29-03-2009, 05:23 AM

My sti's original pulley was on it's way out anyway (outer ring debonding from the rubber isolator) so it was time to do it.

reflexwrx · #8 29-03-2009, 12:43 PM

There was a guy from the forum that was going to sell me his pulley kit but i have deleted the msg by accident. Now i don't know who it was and i can't respond to the msg. Hopefully he will see this thread and send me a PM again.

nachjoe · #9 29-03-2009, 12:51 PM

What brand pully kit was it mate?

reflexwrx · #10 29-03-2009, 02:37 PM

GFB Pulley Kit dude. I just deleted my inbox because it was full. DANG!!