Worked out great to slow my alternator down a bit! It’s a little bit bigger than expected so I had to use an 800k6 belt with the high mount alternator bracket.
LS 3" OD Billet Overdrive Alternator Pulley 6 Rib 10-10042
Motion Raceworks
10-10042
Motion Raceworks - 10-10042
In Stock - More than 10 available
Ships Today When Ordered Before 2pm CST
$69.99
Racing Use Only, Not Legal for Road Use
Motion Raceworks LS 3" OD Overdrive Alternator Pulley
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
Learn more about alternator pulley sizes and how they affect the performance and longevity of your alternator.
Overall rating: 5.0 / 5 from 123 reviews.
Worked out great to slow my alternator down a bit! It’s a little bit bigger than expected so I had to use an 800k6 belt with the high mount alternator bracket.
Wayne L. 5/5 Verified
Looks great on first 427 LS and Cayman GT4 Gearbox in Lotus Esprit V8!
Michael A. 5/5 Verified
Fitment was great and the shims provided worked for what I needed!
Joseph M. 5/5 Verified
Great product
Kevin N. 5/5 Verified
Awesome experience yall the best !
Pablo R. 5/5 Verified
It arrived from UPS with the box damaged and the package bent with one of the shims bent in half. Other than the shipping everything else fit great.
Ryan S. 3/5 Verified
This billet aluminum pulley is a show piece! On top of that, my alternator will never spin faster than 18,000 rpm. Installation was fairly straight forward but will require a long T-50 3/8” socket drive to hold the shaft and some sort of pass-through 24mm socket. I used a Milwaukee 24mm 1/2” drive socket with four flat sides to loosen the alternator pulley nut. Make sure you use the shims to get the alignment spot on and torque the nut to at least 55 lb-ft!
Nathan D. 5/5 Verified
Works as it should and looks good.
Gary M. 5/5 Verified
Worked perfect. Used one of the included shims to get it set perfect and that was all that was needed. Killed two alternators at 6k and up and this has been flawless since. Idle charging was not affected at all. 10/10
Josh S. 5/5 Verified
Looks great and fit perfectly!
Steve M. 5/5 Verified
Love the brand green Hell yea brother
Austin G. 5/5 Verified
Super impressed with how fast i received my order. Item was packaged great and exactly as expected. Will definitely do business again !
Dennis S. 5/5 Verified
Great quality product looks great works perfectly
William P. 5/5 Verified
It’s a proven part that definitely makes the alternator last a long time. Great product at a great price! Thank you! Jason
Jason L. 5/5 Verified
Makes the appearance of the alternator look good.
Barry L. 5/5 Verified
Another great motion product, got my alternator rpm to a safe max!
Mike V. 5/5 Verified
Super easy install I did have to measure it to make sure I didn’t need the provided spacers. With this pulley, a 10% UD crank pulley, upgraded wiring and a 145A “truck” alternator, I am able to maintain over 13V through a 1/4 mile pass without worry that I’m slowing killing my alternator running 7000+ RPM’s. I have no issue with voltage drop driving around town with my AC on, lights on, electric power steering and electric fans on, with my trans cooler fans on. Electric water pump. Meth injection pump. All going at the same time!
John G. 5/5 Verified
Just what I needed! Thanks Doug and company!
Justin H. 5/5 Verified
Great product performed flowless at high rpm.
Jamie H. 5/5 Verified
Fits like a glove. Still finishing up my motor so haven't put it to work yet but is great quality. Will definitely buy again for my next build.
Jl H. 5/5 Verified
This is what I needed made a big difference.
Homer M. 5/5 Verified
New pulley slowed my factory 145 amp LS alternator down perfect. Went from a 2.25" to this 3", alternator still charges perfect at idle and after letting it sing!
Kyle M. 5/5 Verified
Awesome product. Fixed my over spinning issues that I’ve been fighting for months.
Timothy B. 5/5 Verified
Very easy to install! Hit it with an impact, old pulley comes off new one slides on! Don’t forget to measure backspacing of stock pulley before you remove. Super quality part!!
Preston S. 5/5 Verified
Great parts Just what I needed
Sam T. 5/5 Verified
Awesome product.
Kris A. 5/5 Verified
Excellent quality as always. Super easy to install, zip the nut off with an impact and the pulley comes right off. Did a Katech belt tensioner at the same time and just went to Napa to get a new belt.
Josh P. 5/5 Verified
Real good product, I’m shifting at 7500 and keeps charging never drops voltage. Idle is at 14.3 never drops even with a system
Hugo L. 5/5 Verified
It seems to be performing as advertised, really easy install and it looks great see it for your self https://youtu.be/jdq7ZC11phM
Gabriel T. 4/5 Verified
Seem to be the same but on the higher rpm i noticed no volt dip.
Charles T. 5/5 Verified
I messaged Dalton about my charging issue. I had another “KRC 3.5” from Amazon. It wasn’t charging at idle. He explained that 3.5 is too big for stock size crank pulley. He recommended the 3” pulley. Boom my car charges at idle! Took 5 minutes to change out. Awesome part and awesome guy!!!
Sean M. 5/5 Verified
Awesome fitment, went right on. Fast shipping with a surprise in the box. You guys are the best. Can't wait to afford a cleetus wheel and quick release for it too. Thank you again.
Erich H. 5/5 Verified
Works as it should was able to install without getting a larger belt .
Jeff B. 5/5 Verified
I purchased this pulley to slow the alternator down. On a pass the voltage would drop after 5200 rpm . After I stalling the pulley the voltage maintains as it should. Nicey made product !
Brian G. 5/5 Verified
Fits great. Looks great. Works great. I was going through alternators then found this pulley solved the problem.
Steve F. 5/5 Verified
Perfectly made and slows my alternator down at high rpms
Nicholas P. 5/5 Verified
Kept blowing up alternators spinning the motor over 7k. Powermaster recommended their oversized pulley to fix the issue, but nobody had one in stock. Then I found this BEAUTIFUL piece which solved my problem. Also didn’t affect charging at idle at all (although my motor idles around 1k), the alternator still puts out 14.2 volts on average. Best purchase I’ve made in a long time, thanks again!
Michael B. 5/5 Verified
I ordered this for my 2017 camaro ss and it fits fine so it works on LT too just need to buy a nut for it
John M. 5/5 Verified
For truck accessories ensure you have the larger idler pulley or the belt could contact the alternator mounting bolt. Nice part that helped slow down the alternator.
Nicholas B. 5/5 Verified
Awesome products as always, highly recommend!
Matt O. 5/5 Verified
