John_D Power Wrap
Thanks for the great
innovation John. You made life with the
Powerdyne Supercharger much better when you came up with your improved belt
routing.
The Johh_D Power Wrap is the number one most
important mod you can do to your RKSport/Powerdyne setup. It increases the amount of ‘belt wrap’ on
the blower drive pulley and in turn reduces slippage. It requires a little clearancing of the oil filter extension
elbow. This can be done with power
tools such as a Dremel or even quite easily with a Rasp file. The metal is very soft. If you do not clearance the elbow your belt
will wear out prematurely.
If you are using a 3.12” 6lbs pulley you
can most likely still use the 105” serpentine belt that came with the RKSport
Powerdyne kit. There is enough room in
the tensioner bracket to take up the slack.
NOTE: While using the stock
metal tensioner pulley in place of the RKSport plastic tensioner pulley the
metal pulley was rubbing on the heater hose inlet. I simply put a washer between the tensioner bracket and the main
tensioner pulley-bushing bolt. With
that washer in place I can use the stock RKSport serpentine belt and use the
full ‘pull’ of the tensioner bracket.
If you are using a smaller 2.9”, 2.8” or
2.7” (9lbs pulley) you may want to switch to a shorter belt…such as a 103 or
103 3/4” belt. I have a Gatorback belt chart right HERE. You can use the part numbers at the parts
store to cross reference a Dayco belt if you prefer that brand. The 103”
Gatorback is #4061030 and the 103 ¾ is #4061037.
Most Powerdyne users seem to recommend
either gatorback or dayco belts.
Below
is a link to John’s website where he details the ‘Power Wrap.’
http://community.webshots.com/album/71419072LqmYdc
Um, last I checked the pic showing the clearancing of the oil filter extension was not on that site. I am posting it below…. just in case.
Again, Thanks John.
|
Clearancing the oil filter
extension |
In the above pic you can see wear John has ground down the oil filter neck. You can also see the A4 tranny fluid lines. You may need to secure those traynny lines out of the way with ZIP ties or something as the new belt routing will be running right across that area and may rub on those lines.
Better
wrap
The standard kit layout uses a loop between the a/c and crank pulley. They are
4" apart, around a 2.8x pulley, so it's less than 180 degree wrap. The a/c
and idler are 1.5 inches apart, giving better than a 180 degree wrap. The catch
- you have to clearance the bottom of the oil filter extension... A little
scary. I think the belt will need to be about 2" shorter.
In this above pic you can see the
new belt routing. If you still don’t
understand it you will once you get the old belt routing off and do a pre fit
with the new routing. In the upper
right hand corner of the pic is the water pump pulley. After the belt goes around the power
steering unit wrap it around the water pump pulley then down to the crank
pulley then ACROSS to the AC pulley.
Leave a loop in the belt as shown then around the ribbed idler pulley
then under the new tensioner pulley and over the alternator pulley. From there it is a straight shot down to the
Power steering pulley.
John has
since performed an LS1 swap. He is
still around our favorite V6 Fbody forum, though. Don’t forget to thank him.
If you want some interesting reading do searches on the Powerdyne
slippage. The older “Pre John_D Power
Wrap” posts are quite a bit different than the ones you see now. He made a big difference in the performance
of the L36 Fbody Powerdyne.
Here is a taste of history: originaly posted by John on 12-02-03
I've been studying and trying to re-engineer the belt layout on my powerdyne for 3 days now...
I finally stumbled onto a simple solution that provides a little more wrap, while using all the standard kit brackets, pulleys, and tensioner. I had been looking at repositioning brackets, redesigning the tensioner, all kinds of stuff.
This solution required only one little additional modification -- clearancing the bottom of the oil filter extension. And it eliminates the need to remove the plastic piece and the bolt nipple near the crankshaft pulley.
It brings the belt back around to within 1.5" of itself, instead of the 4" spread between the a/c and crank pullies.
Here are a couple of
webshot photos showing what I did. (there's some text that goes with each one
too.) 
http://community.webshots.com/photo/71419072/102791452cjOnEy
http://community.webshots.com/photo/71419072/102792088cUdKlq