Powerdyne pulley sizes, part #'s, + 1 question

[John_D.]

I've seen numerous posts on powerdyne pulleys over the past two years. The things people have tried, to minimize slippage. Questions about pulley sizes.

Now that I've bought a powerdyne kit, I've been prowling around a little. And now I have some information on the pulley sizes. And a question...

First, the pulley sizes:
6lb 3.12" PD-D10045-312
9lb 2.93" PD-D10045-293
12lb 2.70" PD-D10045-270
They are $69 each, from superchargersonline.com, and they also happen to be 6 rib pulleys.

And that leads me to my question... Since these pulleys are already ribbed, they should work as well as the ones people had machined with ribs, yes? Or is there something different about the machined ribs?

[ November 07, 2003: Message edited by: John_D. ]</p>

[Tyler]

i would say the ones that were done at the shop would work better than the ribbed.

because the ribbs on the ribbed on are running parallel with the belt.

the ones done personally are running perpendicular.. like gripping edges for the belt

[John_D.]

I'm seeing what looks like three different pulley mods.

SSMS has the grooves running from side to side, spaced 1" apart, and is holding 5-6psi.

Greenglow has 13 grooves running completely around the pulley. 1/16" in the center. 6 on each side of it, that are either 1/32" or 1/64". He is holding an average of 8psi.

Mighty Thor has a hybrid, with 5 grooves running completely around the pulley. They are 1/16" each. And he has four grooves running from side to side. I didn't see what psi he gets with it though.

Guys - chime in here, and tell me if I understand your pulley grooves correctly, and Mighty Thor - what psi are you holding on yours?

Also, Greenglow, do your grooves look like ribs on a regular ribbed pulley? Or are they sharper, or what?

[98GREENGLOW]

Not sure I understand your question but I will say this... I HONESTLY dont think it matters if you buy them already ribbed or have it done. The bottom line is that it was desighned to run off a smooth pully. Any thing you have that will make the pully grab the belt will do it, weather it's my desighn or Thors or whatever. PERSONALY I would go with the one from ASP, I have heard nonthing but good news about them on www.superchargers online.com. At first I was only getting like 6 psi with my grooved pully but after a week or so it just kept going up and up till I was getting 9 psi.

[John_D.]

<blockquote>quote:</font><hr>Originally posted by 98GREENGLOW:
Not sure I understand your question...<hr></blockquote>

Basically, I want to know if the standard ribbed pully will grip as well as the custom machined ones.

I suspect the standard ribbed pulleys have rounder edges, and larger grooves. Both of these will mean less contact area. Compared to a machined pulley which may have more contact area and non-rounded edges (for better grip).

Then Tyler added to it, by saying the grooves don't even go around the pulley, that they only go side to side.

I know the ribbed one is different than the flat one... And I know your machined one has worked well. But I don't want to assume a ribbed one works as well as yours. And I want to know what to ask for, if I have one machined.

Because of all the experimentation that's already been done, I'm happy to use a design that's proven, rather than go experiment some more.

[Mighty Thor]

Greenglow is right, I would go ASP pulley. There reputation is great. My next pulley would come from them. Let them know your situation and let them do the grooves. Or Greenglow's mechanic.

The ribs part won't work because it's V grooved and that would mean less surface grip. Besides, you would need the 8 ribbed pulley than the standard to make it work.

[ssms5411]

I'll let you know about my experience with the ribbed pulley from powerdyne. I ordered a 9lb 6 rib pulley(which is 2.90 or around there) from powerdyne about 8 months ago and tried it for about a week. My results were, I had to tighten it really tight to get 6lbs of boost and it ended up shreding my belt into pieces after a week. Also when it shreded my belt,pieces of the belt wrapped around my power steering pump and tore the seal. I might try to grind the grooves down to make it smoother but I in the process of getting my engine rebuilt and I still have to see what the pulley from ASP will do after my rebuild.

[ November 08, 2003: Message edited by: ssms5411 ]</p>

[John_D.]

Thanks for all the feedback everybody!!

I don't have the kit yet, but am getting excited about it anyway... :D

So, if I contact ASP, I just tell them to put some grooves in it, and they'll know what to do??

I did research many posts on the powerdyne tech forum too, but didn't see specifically what to ask for...


Mighty Thor - tell me the psi you're holding with your pulley... (unless it's privileged information) [img]smile.gif[/img]

[98GREENGLOW]

Yea I see what your saying now. Mine go around the pully the same way a ribed one would. only differance is there not as deep and I have 13 vrs the 8 I would opt fot if I purchased a grooved pully. I have none that go side to side on the pully. GRT THE DAYCO BELT!!!!! YOu will pick up atleast a pound of doost from just this simple mod. It is by far superior to the gates belt. The dayco can be sprayed one time with dressing and stays that way. It seems like it almost gets sticky on it's own. The gates belt will just get hot and expand. Im only seeing 7 psi with the gates belt (still no retightening though) The dayco belt gave me atleast 71/2 at a minimum. Usualy more like 8 or 9.

[1998mibird]

John_D posted pulley sizes and part numbers on Nov. 7 03.

[John_D.]

I'm not so sure those sizes are correct for our application now...

I don't know what the correct sizes are though.

Those are ribbed pulleys for a different setup. Probably mostly depends on the diameter of our crank pulley.