Frequently Asked Questions


I have X blower on Y car, what pulley do i need?

This sums up the majority of the emails we receive. We usually cannot assist in this manner without knowing a few things first.

1. How many grooves does your current pulley have?
2. Is it a press fit, keyed, or modular pulley type?
3. What is your supercharger shaft diameter?
           0.64" or 0.78" is typical.
4. What is the offset measurement of your pulley?     See diagram below.

Just because you have an M90 for example doesn't mean that all the pulleys on M90 blowers are the same and are interchangeable. For instance an MP45 Blower on one vehicle usually has a different pulley offset measurement than the same MP45 Blower on another vehicle.

A supercharger pulley without the proper offset measurement would not line up correctly with the other engine pulleys, and would eat up belts, or throw them off the pulleys completely.

We need to know the above information before we can assist you properly. If you email us or call us we will ask you those above questions, if you don't know the answers we wont be able to assist you much further in most situations.

How do I determine my offset?

The offset measurement determines the pulleys relationship to other pulleys, or how far out the pulley will stick out in relationship to other pulleys. Not enough or to much offset measurement will result in the belt slipping off the pulley.

This is accomplished easiest by placing the pulley with the long boss down on a flat table and measuring up to the middle of the first groove you come up to with a set of calipers, in inches preferably. ;)

I have read that i should scuff my press fit pulley in order to install it. Is this true?

No! Do not scuff the pulley anywhere before install, especially where you press it onto the supercharger shaft.

How do I determine how much boost a certain pulley will supply me?

A good rule of thumb is that every 1/10" decrease in pulley diameter will produce approximately 1psi. Some of these numbers we have in the details of the specific pulley in question where customers have emailed/called us and given us their unique boost numbers with certain size pulleys. These numbers are very relative to the application in question and your numbers may very well be different.

Pulleys are not measured by psi numbers. Please do not call us and ask us for an X pound pulley, please ask for the diameter of the pulley in inches. Please keep in mind if you email us about wanting a 9psi pulley or a 11psi pulley etc that we wont be able to help you much, you need to tell us the diameter of your current pulley in order for optimal help.

Where can I find the puller/installer tool instructions?

The instructions are in PDF format and can be downloaded/opened below.

M112 Puller/Installer Tool Instructions

M62 Puller/Installer Tool Instructions

M90 Puller/Installer Tool Instructions

Do you rent puller/installer tools?

No we do not.

Can I return my pulley?

We will accept returns only if the pulley has not been installed, there will be a 25% restocking fee. Be sure to line your pulley up and make sure it will work correctly before installing your pulley in order to avoid a refused return.

How do I determine my pulley size (diameter)?

How much will it cost to ship my parts to my country?

If you want to know what it will cost to ship certain parts to your location or what the cost of (x + y + z) parts total cost will be please simply add them to the shopping cart, and proceed to check out, before finishing the checkout procedure it will give you shipping totals for different varieties of shipping.

How do you usually ship?

We are located in the United States. We typically ship UPS, however United States Postal Service is provided as an option for international customers due to the lower rates.

Keep in mind that the U.S.P.S. tracking service is horrible at best and we can not guarantee that you will receive your package in a timely manner, although UPS is more expensive its tracking systems and service is far superior. International customers please keep this in mind when deciding which service you would like to use.

If you choose to ship something via U.S.P.S First Class International Mail you will not be receiving a tracking number, nor is there a way to guarantee its actual delivery. You will be relying entirely on the United States Postal Service, you get what you pay for, however this method can be cost effective with cheap light weight parts, and you have 2-6 weeks to kill. You will not be refunded for parts sent via First Class Mail that are lost by the United States Postal Service, use at your own risk.

What is estimated delivery time to my country? (Not USA)

International orders going via USPS express typically take anywhere from 5-10 days. UPS International can take 1-5.

Can you write a lower value on the customs paperwork for international orders?

We can not do this for insurance/fraud purposes.

How much would my order cost in my countries currency?

You can convert any currency here.

What type of payment do you accept?

We accept all major credit cards and Paypal payments via the website.
We also can accept wire transfers if you have no other payment methods available to you.

Will I be charged tax on my order?

We will only charge you tax if we are shipping to Washington Stage, however if you are an international customer your own countries customs will probably charge you a VAT tax. Typically customs fees will cheaper if your items are shipped via usps, and more expensive with UPS.

Will UPS ship to a Post Office Box (PO Box)?


My pulley wont fit over my supercharger snout, what can i do?

Some but not all superchargers may have to be modified in order to suit a pulley smaller than 2.7" in diameter. This is because the supercharger snout may be to large to accommodate anything smaller than 2.7".