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When you're going to replace a belt... do it right!

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Old 08-01-2006, 02:31 PM
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AO
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Default When you're going to replace a belt... do it right!

As many of you know, I shredded my super charger belt the morning of our event last weekend (Fresh Water Frenzy - Sharks in Hell).

Luckily DR had provided me a spare belt, and I wasn't far from home. You see, one of the unique features of DR kit is that you retain your stock crank pulley, and the belt that drives the super charger also drives the alternator. In fact you use the alternator's adjustment to tension the belt. But the down side is that if you shred the belt, you have to run on the battery - so there is a limit to your range.

I pulled the rad fans and began to route the belt. Now I was in a bit of a hurry and I had the belly pan on - but didn't want to remove it, so I was hoping I could get the belt on and have enough tension to join the event.

Success! And it only took me 15 minutes! I was one happy camper. Tension seemed good.

But I noticed a lot of belt dust and it seemed like the belt was slipping. I thought it's probably because I didn't have enough tension. I went to fiddle with it last night, and it just didn't seem right. That is untl DR sen me a picture this miorning! D'oh! You can see how I had it routed in red.

Moral: Make sure you know the path, before you install a new belt! :bandhead:
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Old 08-01-2006, 02:36 PM
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Hey Andrew, you almost almost had it right :-).
Old 08-01-2006, 02:37 PM
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Thanks.
How's your new beast?
Old 08-01-2006, 02:42 PM
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Any ideas on why the original belt shredded?
Old 08-01-2006, 02:45 PM
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PorKen
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DR should put a sticker on the front with the belt routing for, uh... people like Andrew.

I'm going to have one made for the liftbars.
Old 08-01-2006, 02:48 PM
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Big Dave
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Andrew...any idea why the SC pulley gets scorching hot? The first thing I wondered was whether such a high temp will shorten the belt's life.
Old 08-01-2006, 02:55 PM
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Originally Posted by Bill Ball
Any ideas on why the original belt shredded?
If you look at teh picture below, I think it was rubbing on the edge of pulley #2. I remember finding a small frey when i got back from SITM, and I simply trimmed it off and didn't think much of it. Now the belt may have been defective, or maybe it got nicked with all the comotion. Not sure. But it seem very close to the edge of that pulley. I'm going to stick one more shim (washer) behind there to bing it out just a bit. Should be fine then.

I'm really surprised it didn't shred with the way I had it routed. You can see how close it gets to the crank!
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Old 08-01-2006, 02:56 PM
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Originally Posted by PorKen
DR should put a sticker on the front with the belt routing for, uh... people like Andrew.

I'm going to have one made for the liftbars.
Why would you want to tell people how to route the belt on the lift bar?
Old 08-01-2006, 02:57 PM
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Originally Posted by Big Dave
Andrew...any idea why the SC pulley gets scorching hot? The first thing I wondered was whether such a high temp will shorten the belt's life.
I'm pretty sure it's because it was slipping = friction = heat!
Old 08-01-2006, 02:59 PM
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Andrew you bonehead
Old 08-01-2006, 03:22 PM
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Originally Posted by heinrich
Andrew you bonehead
Thank you, sir! May I have another!
Old 08-01-2006, 03:24 PM
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LMAO!
Old 08-01-2006, 03:35 PM
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Beast is doing good. I got it last Saturday via Intercity Lines (of course it rained all weekend till yesterday morning). I will be installing the ARM, boost gauge and fuel pressure gauge this weekend. Do you have a good web site on how to tune a SC 928? I need to get used to the 928. My n/a Auto 1988 does 0-60mph in 5.5 secs while the SG takes 5.8 secs but pull a lot stronger than the Auto (maybe my g-tech is kaput? or I need to learn driving a stickshift 928 :-)).

Thanks...
Old 08-01-2006, 03:46 PM
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Get used to the stick before you do too many 0-60 pulls or you'll fry your clutch! The best way to tune it is to record your Air/Fuel Ratio. I have the LC-1 widebade O2 sensor from Motorsport. It has the ability to datalog on to your PC. Then you can see how your AFR is doing. Once you have the tools to do the measuring it's a matter of spending time with it and getting the right fuel delivery. The alternative would be to contact DR and rent his sharktuner for a weekend and burn a custom chip. But I would first spend some time getting to know it. Feel free to post a separate topic. Better yet, you should start reading the Twin Screw thread. It'll take you a couple of hours to read it, but you'll learn a ton! Then post questions there.
Old 08-01-2006, 04:04 PM
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Originally Posted by PorKen
DR should put a sticker on the front with the belt routing for, uh... people like Andrew.

I'm going to have one made for the liftbars.
That was exactly the first thing that came to my mind too. Every car now days has a sticker that shows the serpentine belt routing. DR should add this into the kit. Most of the time, serpentine belts only fit one way, but in this case they work in two different ways.
If there is more than one way to instal something people will do just that.


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