Menu

Shop

Garage

Cart

Account

Product Summary

3.75" Inside Diameter, 4.25" Outside Diameter

  • The easiest and most accurate way to seat your rings in the cylinder bore for piston ring end gap measurements
  • One tool covers 4.000" thru 4.230" cylinder bores thanks to different diameters machined into each side of the tool
  • Made from 6061-T6 anodized aluminum for great looks and long service life
  • Designed to fit within installed cylinder head studs, saving you the time of having to remove your studs to use the tool
  • Hollow ring design allows confirmation piston ring is square in the cylinder bore, unlike using a piston to push a ring into place for measuring
See more details

Key Specs

MFG. Part #91089415
BrandSpeedway Motors
Inside Diameter3.75"
Outside Diameter4.25"
See more specs

Need To Know

Quick and Easy Returns

Return Policy

Speedway Motors 91089415 Details

  • Squares your piston rings in the cylinder bore for file fit measurements
  • Fast and easy way to ensure your rings are square in the bore before measuring
  • More precise and easier to use than using a piston to square your rings in the bore
  • Dual sided tool made from 6061-T6 anodized aluminum for long service life
  • Suitable for bore diameters from 4.000” to 4.230” depending on side of tool used
  • Piston ring tool can be used with cylinder head studs installed

Proper Ring Gap Is Critical to Engine Performance; Our Ring Squaring Tool Makes the Job Easy

Building an engine, no matter if it is a low-buck cruiser or a high-end race engine, ensuring your piston ring gap is measured and adjusted for the performance expectations of that engine is vital. Piston ring end gap must be measured in the cylinder bore of the engine the rings are being installed into. It has been common in the past for many an engine builder to simply grab a piston and use it to push the piston ring down into the bore. While this may have worked, there is little to guarantee that the piston ring is truly square in the bore for a precise piston ring end gap measurement. Like any job, using the proper tool to get the job done will save time and provide more accurate results. This is why a piston ring squaring tool should be a part of your engine building tools collection.

Our piston ring squaring tool is made from durable 6061-T6 aluminum and is anodized for good looks and lasting protection. We designed our piston ring tool to work with a cylinder bore of 4.000” diameter up to 4.230” diameter by providing two different bore sizes in one tool. Simply flip the tool over to use applicable fitment for your engine block. For smaller bore engines, such as the popular LS, we offer a piston ring tool sized to work with 3.736” to 3.810” cylinder bores. The piston ring squaring tool provides the user the ability to seat the piston ring tool quickly and easily to the block surface to position the piston ring in the cylinder’s bore. The open center of the piston ring tool allows the user to reach into the bore and pull the piston ring up against the piston ring squaring tool, confirming that the ring is indeed square in the bore for measuring with a feeler gauge.

The outer diameter of the piston ring squaring tool allows for use on blocks with head studs in place/installed as well, saving you further time of having to remove your studs to check and set piston ring end gap. Note that this piston ring tool is only designed for squaring your piston rings in the cylinder bore and is not a piston ring compressor. We offer piston ring compressors in six different size ranges to safely compress your piston rings and aid in installing your piston and rod assemblies.

Speedway Motors 91089415 Specifications

KEY SPECS
MFG. Part #91089415
BrandSpeedway Motors
Inside Diameter3.75"
Outside Diameter4.25"
GENERAL
Sold in QuantityEach

Ratings & Reviews

4.9

24 Reviews

Overall Assessment

Customers universally applaud this ring squaring tool for its top-notch quality, ease of use, and time-saving benefits. Crafted from machined aluminium, it's hailed for providing precision in squaring rings in the bore, thereby enhancing ring end gap checking. This tool covers a wide range of bore sizes and is essential for serious engine builders due to its ability to set up every ring gap at the same height and square to the deck surface. Customers wish they'd purchased it sooner, acknowledging its superior usability and practicality over similar competitor products. The tool is also noted for being lightweight, durably built, cost-effective, and for improving accuracy in file fitting rings, making it a highly recommended purchase.

4.9

24 reviews

5

22

4

2

3

0

2

0

1

0

Filter by Ratings

Works perfectly

5.0

2 years ago

DoubleJ

MO

Verified

Works perfectly to square rings in the bore

Would Recommend

Worked great

5.0

4 years ago

Big Krugs

Valley, Ne

Verified

Good quality craftsmanship

Would Recommend

great little tool

5.0

5 years ago

Nick

Kansas

Verified

I wish you had one for a small bore cylinder 3.875 to 4.0 at the same price.

Would Recommend

Works well

5.0

5 years ago

BM

IL

Verified

Beats using a piston

Would Recommend

I would buy this again

5.0

6 years ago

Tb

Mi

Verified

Worked great

Would Recommend

Yes

4.0

6 years ago

Fishman

Vancouver Island

Verified

Great product

yes

5.0

6 years ago

jim the runner

right here

Verified

good

Would Recommend

Very happy with this :)

5.0

6 years ago

Tormod

Norway

Verified

should have bought it years ago. it does exactly what it should. makes gapping a breeze.

Would Recommend

Worked Great!

5.0

6 years ago

Steve

Oak Grove, MN

Verified

This thing is a huge time saver. It worked awesome to square up the rings in my Chevy 383. The time it saved me definitely made it worth the price. It appears in the picture to be made out of plastic but it is actually made out of machined aluminum. Would definitely recommend.

Would Recommend

Nice tool. Well made.

5.0

6 years ago

STOFFER

Willard, MO

Verified

Nice tool.

Would Recommend

Load More Reviews

Showing 10 of 24 reviews

Customer Impersonation Script