New Exhaust System

Though I thoroughly enjoyed porting the stock exhaust, I decided to go with a complete upgrade this time. I used the New Era header with a used RB 063 tuned pipe I got for cheap from a fellow racer. The setup looks great:

The exhaust nipple is a Hobbico 1/8th scale part that I dyed orange, and the exhaust coupler is a Kyosho silicone unit.

I was not happy with the fit of the New Era header setup. The adapter (apparently a copy of the Kyosho model for OS engines?) has an opening which is completely circular and doesn't match well with the odd-shaped GS21R exhaust port. The header itself also has a very sharp turn that is not condusive to smooth exhaust flow.

In testing, I was very disappointed, not noticing any difference in performance versus my ported stock system. For the price, I think it'd be better to get the Kyosho "special manifold" set which has the same round port for OS engines, but at least has a smooth-flow header. Perhaps this would allow the benefits of the better pipe to shine through.

I'll try my ported stock header soon and report back with the results.