Magnum Powers 15%-25% OD No-Slip Pulley kit Group purchase

XR7 Dave

Registered User
There has been great response to the MP 25% OD pulley combination that we used on the MPX blower test car but the pulley arrangement on that car is custom with a one-of-a-kind blower pulley, ESM JS pulley, and MP crank pulley. I have talked Charles into drafting up the design for a MP version of this custom setup. The only thing is we have to let him know that we really want this setup by placing orders before he can have production started.

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Hadn't occurred to me initially but for those with an MPI, S-Port, or other ported blower, the 10% JS and 5% 10 Rib blower pulley combo would be an excellent combination with a stock or UD crank pulley. A great way to eliminate belt slip on that combination too.
{Edit}

Details on the pulley setup:

All pulleys will be made from 6061, sand blasted for adhesion, and then hard annodized for long life.

The crank pully will be the same as is currently offered from MP with stock acc. drive ratio and an 8 rib JS pulley drive. The JS pulley will also emply a 10% OD and will have an 8 rib driven side and 10 rib drive side to the blower. The blower pulley will be a 10 rib press-on 5% drive size.

The group buy will allow you the option to buy either all 3 pulleys or just the two uppers if you already have the crank pulley.

Included with the purchase is also both MP high tension springs for the tensioners and Gates belt (or belts depending on which package you get) which are known for having the best grip and longest life for this kind of application. This is a group purchase benefit only!

Here is the link: MP Pulley Group Buy Link.

Minimum 15 orders needed to begin production.

If you have an MPIII or plan on getting the MPX you NEED to get in on this now!
 
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It will be blasted but not hard annodized due to the need for the press fit to the blower shaft.

Cant you do that, get it hard anodized and then reclearence for a pressfit. Teh cost may = the same or even less then using the higher grade aluminum and still get better wear characteristics. I dont see myself needing this but just athought
 
Cant you do that, get it hard anodized and then reclearence for a pressfit. Teh cost may = the same or even less then using the higher grade aluminum and still get better wear characteristics. I dont see myself needing this but just athought

It would be best to have all the pullys anodized to reduce wear. Type II anodize typically builds all surfaces .0004" - so make the ID .0008 larger. If one has trouble fitting to shaft, hone the pully ID with a brake hone in the drill. Thats what I did and it worked well. IMHO 7075-T6 is over kill - 6061-T6 would be fine and much more available.

Mike
 
Charles has informed me that all pulleys will be hard annodized 6061 as the revised post above shows. Thanks for the suggestions.
 
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Ok, either one of these kits come with an 8rib/10rib JS pulley correct. Stock or UD crank pulleys only have a 7 rib belt. I should be OK to run this setup still, correct? I will be using an SCI stock size crank pulley this year. If so I will be placing my order without the crank pulley just to get the 10 rib SC belt.
 
Ok, either one of these kits come with an 8rib/10rib JS pulley correct. Stock or UD crank pulleys only have a 7 rib belt. I should be OK to run this setup still, correct? I will be using an SCI stock size crank pulley this year. If so I will be placing my order without the crank pulley just to get the 10 rib SC belt.

Yes, you can run a narrower belt with no problems. The belt will align towards the back of the pulley leaving one rib at the front exposed.
 
In case no one is paying attention.....;) this group buy only commences when we have 15 people put down deposits. So far Charles has 3.

People, this is the solution to belt slip issues that have plagued SC owners for years. If you want this setup to be an option in the future, some of you will have to pony up and get it now. If you don't really care about eliminating belt slip then there really isn't much point in proving that an M90 can make over 400rwhp because no one will be able to at which point the naysayers will have a self fullfilling prophesy.

For those who haven't been paying attention. BELT SLIP WILL PREVENT YOU FROM MAKING 400RWHP WITH YOUR M90.

Do you want to be able to make 400rwhp? Or do you want that to just to be something of legend so people can say "yep, back in the day someone said they made 400rwhp but I don't really believe it." The choice is yours and history will, to an extent, be decided here.

For those who think "I will wait and see if my belt slips." Don't take for granted that options will exist forever.
 
If you want it polished, you can apply a powder coating to the faces if you want to.

Hard Anodizing is the only way I'll ever buy pullies after what I've seen from those that aren't. It's one thing if it's just a track car or show car. But if you're gonna be driving it places, you want those pullies to last.

Is this for the MPIII and MPX due to fitment issues on the blower pulley, or due to total waste of time on anything else?

Checked the bank... I'm in. (wife can find out later when UPS man arrives)
 
Is this for the MPIII and MPX due to fitment issues on the blower pulley, or due to total waste of time on anything else?

The 3 piece set provides 25% OD which is too much for anything short of an MPIII. However, the pulleys are 100% compatible with all other crank pulleys so if you bought the upper 2 pulley option for say an S-Port or something like that, you would get the best grip possible on the upper 2 pulleys, 15% OD, and the remaining stock or aftermarket pulley would only be the crank pulley which is the slowest moving and largest diameter pulley making it the least likely to slip of all pulleys.
 
Here is the reply I got back from Charles regarding the setup using a stock crank pulley. Just to help get this moving.

Charles,

I am interested in purchasing the 15% OD kit, but have a simple question
before I purchase the set. Will the 8 rib JS pulley work with the stock
size crank pulley with the stock size 7 rib JS belt? I would like to run
this setup for my MP2 to help eliminate the slip using the 10 rib SC belt.

Thanks
Ryan



Ryan,
Yes it will. The MP 10% crank pulley has an extra rib forward of the
standard 7. If you have a stock crank pulley just run a 7 rib belt in
the rear 7 JS groves.

Charles
 
Thanks guys. I placed an order last night for the full set. Note I didn't even see this thread until last night.

What some folks may not realize is that Charles has worked out a very good design for pullies that has a significant reduction in the potential for belt slip. A 15% overdrive set that cuts slip quite a bit is a heck of a deal at this price especially for those considering a future, if not immediate up grade to their blower.
 
A 15% overdrive set that cuts slip quite a bit is a heck of a deal at this price especially for those considering a future, if not immediate up grade to their blower.

Agreed, now is the time. People are not going to beat this price. I placed my order for the 25% OD set the night before the Group Buy was announced so I know it is a GREAT deal, basically getting the belts and springs for free. The key to making big M90 power is before us at a discounted price. Hmmmm, what should I do? :rolleyes:
 
Have one more question, what tensioner pulley is being used for the 10 rib? I use dayco 89016 tensioner pullies.
 
Got my deposit in. Now I guess I'd better start saving up for the power package or MPX so these pulleys arent left sitting in the box forever.

And here I wasnt planning on spending any money on this frigin' car for another 6 months...

Bit by the SC bug again......and you guys are to blame! :D
 
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