Calling future mods as a Change a cooling head and button are total wastes of money..

Silver is standard glow plug and orange turbo.

Read back thru any of the 100 plus pages before wasting your money on useless purchases like a orange head that does nothin for you.

Some believe that the non-tuned version runs stronger across the curve vs the tuned turbo version. I agree and have compared the 2.

If you want to get the most out of engine. Learn how to tune it and recognize glow plug and air leak issues vs chasing down a bad tune. Also, running the car for a minute and then full speed runs then adjusting the carb settings hurts more than you can understand.

Now-if you want to spend money that will get you results-send the engine to a good engine builder like pro twister or powerhouse. I think zixxer has one from both I think. I went with pro twister as a personal choice based on my needs.

Other than that a proper pipe and clutch setting gives you more power than you could imagine.