Our 2 into 1 merge collectors are machined and hand fit to perfection. From there they are purge tig welded and blended for optimal flow. This smooth transition maintains exhaust velocity, improving volume to efficiency. Available in a variety of merge sizes. This 1 7/8” primary 2 into 1 merge collector comes with the inlets expanded to accept a 1 7/8” primary tube. If you would like to add collector tabs to your custom collector, let us know in the order comments at checkout.