Tuning Tools

Gear Ratio Calculator

Estimate vehicle speed from tire diameter, transmission gear ratio, axle ratio, and RPM. Use this as a planning tool for tire and gear changes before requesting calibration updates.

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Common transmission gears: 4L60E overdrive 0.70, 4L80E overdrive 0.75, 6L80 sixth 0.67, 8L90 eighth 0.65.

Estimated Speed

0.0 MPH
Formula: MPH = RPM x tire diameter / transmission gear / axle ratio / 336. Tire and gear changes often require speedometer and shift schedule updates.

J.R. Jones Racing LLC Tune Files & Cam Kits

Use these tools to confirm your engine, drivetrain, tire size, gear ratio, or RPO codes before ordering. Once you know what you have, J.R. Jones Racing LLC can help match your vehicle to the correct tune file, camshaft tune, DOD/AFM delete tune, MDS delete tune, or cam kit.

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Connected to the catalog

Carry drivetrain changes into the tune order

Add the measured tire size and final drive ratio in the builder so the information stays attached to the matched tune.

Build Your Tune

Select the vehicle and camshaft, choose the tune type, then add only the modifications supported by that path.

Tuning device required: You must have an HP Tuners MPVI2, MPVI3, or MPVI4 supported for your vehicle. J.R. Jones Racing LLC does not currently support RTD or TDN devices. RTD/TDN support is planned for the future. Check device requirements. Need an interface? You can add an HP Tuners MPVI4 to your tune at the bottom of this builder if you would like to purchase one through J.R. Jones Racing LLC. Vehicle credits are sold separately.
Build Your Tune Package
Verified Vehicle Match
Choose Your Path Choose Your Tune Type

Full Custom and Base support listed modifications. Downloadable .HPT files cover only an exact supported cam or delete calibration with no modification add-ons. FIRSTTUNE20 is not valid on downloadable or pre-written .HPT files.

Modifications & Options
HP Tuners Credits are sold separately at HPTuners.com.
Your Tune Match
Choose year, make, model, engine, and cam selection.
Price Breakdown
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HP Tuners MPVI4 vehicle interface

Need an HP Tuners interface?

Purchase an MPVI4 below to include it in the same order as your tune. Vehicle credits are sold separately.

View MPVI4 Details
Final Build Summary
Vehicle
Not selected
Engine
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Transmission / Drivetrain
Not provided / Not provided
Cam
Not selected
Tune Type
Not selected
Modifications
None Selected
Blowers
LSA: No; Hellcat: No
Total
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