In addition to Holley EFI tuning, we also do some GM LS tuning. Primarily Gen3 GM LS using HP Tuners. The GM LS platform is the new small block/big block Chevy. They are used and swapped into everything. There are a few things you can do to help the tuning experience.

• If the GM LS ECU doesn't match the engine or has been changed. Let us know. We'll end up figuring it out one way or another, because the tuning data won't add up. It's helpful to know up front.
• Has someone else tuned it before? - There are a ton of variables in a factory GM LS ECU and each tuner has a different method. It's helpful to know if we're starting from the factory settings or someone has been tuning it before.
• Are there any components that don't match the year/make/model of the engine and ECU? - If throttle body, fuel rails, injectors, have been changed, we need to know to accommodate that.

Once again, we'll figure it out...but it can greatly extend the time it takes, which will likely result in additional charges. Whatever vehicle history you can share will result in a better experience!