GM Alternator, 5/8 Inch Wide Alternator Belt Pulley, Plain
GM Alternator, 5/8 Inch Wide Alternator Belt Pulley, Plain
Speedway Motors

|

#91016250

GM Alternator, 5/8 Inch Wide Alternator Belt Pulley, Plain

  • Adapts GM alternator to original 5/8" belt
  • Compatible on all Powermaster alternators, generators and most GM alternators
  • Bolt hole length is .71"
See More

Finish:

Plain

AluminumChrome

$21.99

/each

In Stock


Quantity

Need Help? Call to Order

Add to a list

Share

Select an engine to verify Fitment

Select Engine

Product Summary

2.89" Overall Diameter, V-Belt Belt Type, Steel

  • Adapts GM alternator to original 5/8" belt
  • Compatible on all Powermaster alternators, generators and most GM alternators
  • Bolt hole length is .71"
  • Zinc-plated for rust and corrosion prevention
  • Premium steel construction
See more details

Key Specs

MFG. Part #91016250
BrandSpeedway Motors
See more specs

Need To Know

Need help?

855.313.9176
View the Help Center

Quick and Easy Returns

Return Policy

Speedway Motors 91016250 Details

So you've converted your Flathead-powered rod over to 12 volts and bolted a GM alternator in place. Now it's time to install the belt, but your engine pulley is 5/8" and the alternator is 1/2"!

Don’t worry, Speedway has you covered. This alternator pulley allows the use of a 5/8" wide Flathead-style belt on GM externally regulated, SI and one-wire alternators.

Speedway Motors 91016250 Specifications

KEY SPECS
MFG. Part #91016250
BrandSpeedway Motors
GENERAL
Overall Diameter2.89"
Belt TypeV-Belt
Overall Thickness1.28"
Hole Diameter.67"
Belt Width.68"
Material TypeSteel
Inside Diameter1.38"
Groove Count1
Inside Length.52"
FinishZinc Plated
Sold in QuantityEach
NotesBolt hole length is .71" Pulley will work on all Powermaster alternators/generators as well as most GM alternators.

Ratings & Reviews

4.9

93 Reviews

Overall Assessment

Customers highly recommend the product for its quality, practicality, and usability in a range of applications, particularly noting its role in alternator conversions. It fits many vehicles perfectly and operates excellently, providing valuable support in the transition from 6 volts to 12 volts systems, fitting classic and vintage models such as Chevy 3100, Hudson, Ford 8N, WWII Jeep, Ford Flathead, and Willys Jeep. Users are delighted with its top-notch machining and compatibility with 5/8" belts, better aligning with old-style engine systems. The pulley can handle wider v-belts, enhancing its practicality, and customers appreciate its solid construction.

Write A Review

4.9

93 reviews

5

87

4

6

3

0

2

0

1

0

Filter by Ratings

Great experiene

5.0

3 months ago

Stmay166

Hilton Head, SC

Verified

Needed to have the alternator pulley extended a bit. This pulley was idea to pick up the 1/4" to align the fan belt.

Would Recommend

Exactly as ordered and as needed at good price.

5.0

5 months ago

Bruckman Engineering Inc

Albuquerque New Mexico

Verified

Great fit, excellent finish and good material

Would Recommend

I would recommend works great I didn't have any modificatio

5.0

10 months ago

Rando

Baxter Springs

Verified

I used it on a 239 flathead 1947 truck

Would Recommend

Worked great

5.0

a year ago

Norm

Edmonton, AB

Verified

Installed on alternator mounted to ford flathead.

Would Recommend

Flathead alternator pulley

5.0

2 years ago

Al

Pa

Verified

Fit well and lined up

Would Recommend

Yes

5.0

2 years ago

Dave

Bieber

Verified

It actually fit

Would Recommend

Perfect fit for an oddball application

5.0

2 years ago

thedynoguy

Webster NY

We used this pulley on a 12v Delco alternator conversion in a 1956 Willys. The spacing is perfect, so now we can use the OEM style 5/8" V belt.

Would Recommend

Perfect fit.

5.0

2 years ago

Michael

Taylor, WI

Verified

I used this pulley on a gm 10si alternator for my bobcat 600 charging system upgrade. Fit was perfect. Would buy again.

Would Recommend

Chevy 216

5.0

2 years ago

Robert

Costa Mesa, Ca

A must when upgrading Chevy inline 216 generator for high amp alternator. 216 engine has 5/8" pullies on harmonic balancer and water pump. This speedway alternator 5/8" pulley fits Powermaster 37293 and 47293

Would Recommend

Worked perfectly!!

5.0

2 years ago

Mike

National City, CA

Verified

1951 Chevy Styleline Deluxe going from 6 volt to 12volt. New alternator came with 3/8" pulley from another company. Order the 5/8" pulley from Speedway Motors, pulled the 3/8 off and installed the 5/8" in 2 minutes and it worked perfectly!!

Would Recommend

Load More Reviews

Showing 10 of 93 reviews

Questions & Answers

2 Questions • 5 Answers

does this require a special nut? I am having trouble having enough space to get the alternators original nut on.

by TimPit

• 10 years ago

2 answers

View Answers

What is the O.D. of this pulley

by Tom

• 15 years ago

3 answers

View Answers

2 of 2 questions shown

Fitment

  • 221 Ford Flathead V8

  • Ford Flathead V8 17 Stud 221 18

  • Ford Flathead V8 21 Stud 221 40

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 255 Ford Flathead V8

  • 337 Ford Flathead V8

  • 239 Ford Flathead V8

  • 221 Ford Flathead V8

  • 239 Ford Flathead V8

  • 239 Ford Flathead V8

  • 239 Ford Flathead V8

Customer Impersonation Script