I am very happy with the converter Ultimate Converter Concepts reworked for me. I had a converter that was setup for a NA 430 and recently switched to a Gen 3 hemi with supercharger. The converter was way off with the supercharged hemi and UCC reworked it. I picked up 6 mph in the 1/8 mile. Ultimate Converter was very easy to work with and the converter is performing great, showing 7% slippage in the 1/4.