Motion raceworks has always had top quality parts that I have grown to trust. I will use them over and over again.
Motion Raceworks LS 3.5" OD Overdrive Alternator Pulley
Motion Raceworks
10-10043
Motion Raceworks - 10-10043
In Stock - More than 10 available
Ships Today When Ordered Before 2pm CST
$79.99
$67.99
You Save -18% ($-12.00)
Racing Use Only, Not Legal for Road Use
Motion Raceworks LS 3.5" OD Overdrive Alternator Pulley
*Note Pictures may reflect 3" pulley size*
Factory alternators can be very dependable and easy to find, which is why most of the aftermarket industry builds front drive bracketry kits around these pieces.
Designed to be used with LS style 6 rib LS Factory style alternators. Simply remove your factory alternator pulley with a puller and press on this alternator pulley.
Note: This is compatible with LS1, LS2, LS3, LS6, LS7, LS9 alternators. Others may be compatible as well.
Machined from 6061 Aluminum
Made in the USA!
Shims included to adjust pulley for inconsistencies in casting, spacing of factory and aftermarket brackets.
Comes with:
.019 Shim
.039 Shim
Please see the below chart for crank pulley size versus alternator pulley speed

Overall rating: 4.9 / 5 from 37 reviews.
Motion raceworks has always had top quality parts that I have grown to trust. I will use them over and over again.
Bill D. 5/5 Verified
Perfect
Maher E. 5/5 Verified
Good looking and quality part at a affordable price
Corey K. 5/5 Verified
Nice piece. Easy install
Duke L. 5/5 Verified
Pulley was exactly what I needed for the rpm I turn this motor.
Michael R. 5/5 Verified
Exactly what I needed to keep the alternator from over spinning.
Bryan T. 5/5 Verified
Quick shipping. Perfect quality. Perfect fit and finish. Saving my alternator from over spinning
Jake T. 5/5 Verified
Very nice piece. Works great and even with the 3.5", the alternator still charges great at an idle.
Jason B. 5/5 Verified
Just what the doctor ordered for my blow C5 with 6.8 LS3
Sam T. 5/5 Verified
Installed on a 105 Amp alternator fit perfectly great looking pulley thanks
Steve M. 5/5 Verified
The pulley will be going on my new turbo build. With the increased rpm of 8700. This will pro long the life of the alternator. Thank you Motion Race works, for your help and money saving tips with this product.
Thomas B. 5/5 Verified
Perfect fit with spacers to make adjustments. Will definitely keep the rpm down to improve service life of alternator.
George B. 5/5 Verified
Best experience I've had with a company lately. Fast shipping, good packing and emails letting know my orders detail. The pulley was as described and very good quality, works great. Thank you
David A. 5/5 Verified
Awesome pulley! To be honest my setup doesn’t need it but it cleans up the engine bay very well. If you have a truck motor I had to go up three sizes from the oem belt.
Michael L. 5/5 Verified
Belt hits water pump fitting. Bigger diameter means different path. So happens to be I'ma welder so no big deal. Easy bolt on. Quality product. Not on back order. Couldn't be happier.
Alex D. 5/5 Verified
After having one alternator die from over revving decided to order this pulley. Car has better voltage everywhere now and the quality is best in the buisness and even looks great! Would definitely recommend it to anyone
Gino F. 5/5 Verified
Fit my new power master 200 amp adjustable voltage alternator perfectly. Perhaps I misjudged the size as I do have low voltage at idle. The chart showed I would be tickling that 18krpm if I went with only the 3 inch pulley. Very nice piece, super easy to install.
Marc B. 5/5 Verified
Looks bad ass and I'm sure it'll perform the same.. made in the USA for the Win
Jose C. 5/5 Verified
Shipping was quick and part as always is top quality.
Ryan S. 5/5 Verified
Awesome service
James Walter M. 5/5 Verified
Solved my issues works great
Parker A. 5/5 Verified
Did what it was supposed to do - most excellent
James B. 4/5 Verified
Thanks guys great item and fast shipping to Australia
Luke B. 5/5 Verified
Quality craftsmanship, fit and finish as always from Motion Raceworks!!
Steven M. 5/5 Verified
The entire process was excellent. The key to a successful business and return customers is communication. The updates and prompt shipping were on point. Will continue to be a customer.
Steven R. 5/5 Verified
A+++
Mario R. 5/5 Verified
Parts look great!
John E. 5/5 Verified
Fixed my low voltage issue at wide open throttle
Stephen N. 5/5 Verified
It doesn't quite fit the regular LS style alternator shaft correctly. Had to ream it out a little for proper fitment, had like a burr on the edge of the machining be best description. The shims supplied would be great if my order came with both as pictured. Overall its an overpriced piece of machined aluminum in the shape of a pulley, but motion is not for poor folks.
Jason U. 3/5 Verified
Comparing Motorsports companies offering of the same part, same quality, substantially less expensive from MOTIONWORKS!
Dan T. 5/5 Verified
Good product
Robert C. 5/5 Verified
High quality product, and extremely fast shipping. Less than 1 week from USA to New Zealand
Daniel K. 5/5 Verified
💪
Josh W. 5/5 Verified
Excellent. As for information for next buyer, I asked and got the answer that the the I.D. of that pulley are 0.660". False it are at 0.670" +- 0.001" which are std. LS. Other than that false info, great service, awesome quality finish, fast shipping and fit like a glove on LS7 alternator with a custom 0.110" thickness shim.
Sebastien I. 5/5 Verified
Pulley looks great fits great and works great
Clint B. 5/5 Verified
Great made product super light looks killer under the hood
Brent H. 5/5 Verified
I was fighting a power problem. When I would go down the track I noticed everytime I hit about 7200rpm my alternator looked like the 4 the of July! Talking to Power Master, they said because I ran the truck pulley (7"?) it was to high of rpm on the alternator. They said get a larger pulley. It was hard to find, but now I know! Thanks guys for solving problems.
Ron A. 5/5 Verified
