Performance In-Frame Tuning

536 Soscol Ave. Napa, CA 94559 (707) 253-0748

Monday - Friday: 8:00 am - 5:30 pm

Routine Maintenance

"An ounce of prevention is worth a pound of cure". Come to AJ's Auto Repair for ASE certified technicians providing bumper-to-bumper repair services, for vintage and modern cars, foreign an domestic. »

Dyno Tuning

If you are wanting to tune or just dial in your own vehicle our Dyno Rental is just what you need. It runs $150 per hour, and the shop _must_ operate the vehicle while you tune.

We use a variety of software for tuning. I.e: EFI Live, Sniper, Crome, BRE, and Tuner Pro. We can provide your vehicle with an after market stand alone (AEM, Haltec) or we can utilize a piggyback system (Utec, AEM FI/C) with your existing ECU. We also have deep experience tuning with MegaSuirt.

We can also adjust shift points and firmness on many electronically controlled automatic transmissions (New GM & Ford), to improve shifting.

dyno tuning performance cars in napa

Ready, Set...

Before a baseline or tuning session, ensure the following, to make most of your tuning session:
Make sure that the tires are in proper working condition, the dyno can be hard on tires as repeated dyno pulls are needed.

Check all the coolants in the car and if there is a leak and there is a over heat issue, be sure to take care of it before the session.

Inspect that the oil is at a good level before the session and that the filters (air & fuel) are in good shape.

It is a good idea to inspect the spark plug wires and if needed replace them for a new set.

Please be conscious of the fact that an old clutch could fail in a baseline/tuning session. If the clutch fails, session will be over.

Make sure there are no check engine lights or codes present before the tune.

On turbo systems, if we/you are tuning a turbo system, make sure all pipes are properly secured so they do not blow off during the tuning session.

If you are coming in for a tuning session whether we shop tune or customer tune here are some things to consider:

Please bring your own tools if you are self tuning your vehicle, the shop is not responsible for supplying tools.

Make sure you bring a correct set of extra plugs to change before the tuning session.

If you are changing from pump gas to race gas during the session, make sure that you tell the dyno operator ahead of time.

If your vehicle spills excessive fluids on the shop floor, you may be charged a clean up fee.

If any damage occurs to the dyno, the shop, shop's equipment, or any person caused by your vehicle it is your responsibility.

Lastly the dyno operator will always be driving the vehicle and operating the dyno controls.


In a smaller community like Napa, positive reputation is life!

Parts Now

Same day parts delivery!

With us you don't have to wait for parts to be shipped. We have local suppliers who deliver same or next day.