Free for racers

Every Tenth Matters.

Setup calculator, diagnostic troubleshooter, session logger, and rulebook — all in your pocket. Built for racers who wrench their own cars and chase every tenth.

0.1secondsThe gap between winning and losing
SpringsCalculated
Cross-WeightOptimized

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See Your Setup Before You Sign Up

Click the track conditions below and watch the recommendations change in real-time.

Live Demo

Setup Calculator

1975 Monte Carlo

Track Condition

Springs (lbs/in)

LF

900lbs/in
7751025

RF

900lbs/in
7251000

LR

200lbs/in
150250

RR

200lbs/in
150250

Alignment

Camber LF-2°
Camber RF-2°
Caster LF+3.5°
Caster RF+3.5°

Tire Pressure (psi)

LF

14

RF

14

LR

13

RR

13

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Gear Ratio Calculator

Match your rear gear, transmission, and tire diameter to find the RPM sweet spot for any short track. See exactly where peak torque and peak HP land at every speed.

Transmission

1st: 2.522nd: 1.523rd: 1.00

Drivetrain

Effective ratio: 3.73

Engine Reference RPMs

Analysis

Peak torque at 89 mph — may be too tall for this track. Consider a numerically higher (shorter) rear gear.

Peak HP at 114 mph — you'll never reach peak power on this track. Shorter gear needed.

Peak Torque Speed

89 mph

Peak HP Speed

114 mph

RPM at Speed

MPH1st2nd3rd
101,192719473
151,7881,079710
202,3851,438946
252,9811,7981,183
303,5772,1571,419
354,1732,5171,656
404,7692,8771,893
455,3653,2362,129
505,9613,5962,366
556,5583,9552,602
607,1544,3152,839
657,7504,6743,075
Near peak torqueNear peak HPOver-rev (>6500)

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Corner Weight Calculator

Enter your scale readings to calculate cross-weight percentage, weight distribution, and get jack bolt adjustment recommendations — no account required.

Scale Readings (lbs)

Targets

Results

Total Weight

2800

lbs

Cross Weight

50.0%

RF + LR = 1400 lbs

Left %

50.0%

1400 lbs

Rear %

41.1%

1150 lbs

Diagonal Bias

0.0%

Balanced

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Diagnostic Troubleshooter

Answer three quick questions about your car's behavior and get prioritized setup adjustments ranked from easiest to most involved.

1/3

What is your car doing?

Beyond the Calculator

Your Complete Racing Toolkit

Diagnosis, engine builds, session data, corner weights, gear ratios — everything you need to find your tenths.

Engine Simulator

Pro

355 SBC Build

Peak HP

387

@ 5,800 RPM

Peak TQ

452

@ 4,200 RPM

Power Curve

3,000RPM7,000

Session Logger

Pro
FeatureMar 1, 2026

Springfield Raceway

Tacky conditions

Best Lap

14.832

Finish

P3

Handling Feel

Entry

Tight

Mid

Neutral

Exit

Loose

Rulebook

Searchable class rules with tech inspection checklist

Rim Offset

Backspacing and offset calculator for any wheel

Simple Pricing

Free to Start. Pro When You're Ready.

Everything you need to get faster is free. Upgrade to Pro for advanced tools.

Free

$0/forever
  • Setup Calculator
  • Diagnostic Troubleshooter
  • Gear & Offset Calculators
  • Rulebook & Tech Checklist
  • Single Car Profile
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$9.99/month
  • Everything in Free
  • Engine Build Simulator
  • Engine Comparison Tool
  • Session Logging & Analytics
  • Multi-Car Profiles
  • Priority Support
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Built for the Garage

Tenths was built by racers who got tired of guessing. We wanted real setup data, real diagnostics, and a real log of what works — without needing a professional crew.

Whether you run street stock, modified, late model, or figure 8 — if you wrench your own car and want to find your tenths, this is for you.

Find Your Tenths