Hi Troy,
I have been using NMP exhaust on my 160 engines, the truth is that I am tired of changing the hatori 821 o`ring . They last no more than 6 galons of fuel.
Do you have any experience of this combo with the Central Hobbies viton o`ring replacement?
I didn`t buy the hatori header because I saw Marcelo Colombo hatori`s header coming loose almost every 2 flights, any reports upon these combos? Any solution for these problem?
Which combo do you prefere?

I live in Chile , and our experience with the 160 is very poor.

Best regards,
Patricio.

6 gallons seems a bit low...I have run this a bunch and usually change the o-ring about 75-100 flights. The Central Hobby Replacement O-ring is a different size than the hatori. The NMP header is 5/8" and the Hatori is 15mm. So the O-ring size is changed to fit the NMP header. You might have better luck. If you assume about 8 flights per gallon then you should be getting 8-9 gallons per o-ring. If you are not perhaps some better cooling may help.

Troy Newman
Team YS Performance

Thanks,
Patricio.