ORIGINAL: bruce88123
ORIGINAL: Gringo Flyer
ORIGINAL: bruce88123
What does all of this talk about Jetts have to do with getting more power out of a ST 90?
Bruce, do you have any productive discussion to add or just criticism for everybody elses responses.
I asked a question
"What does all of this talk about Jetts have to do with getting more power out of a ST 90?"
What does that have to do with criticism? Oops, another question. Am I criticizing again?
Question here is answered easily. It is in direct response to the "how to".
In fact this answer can be expanded to nearly all 2-C glow model engines.
The exhaust system of a modern 2c engine is where the greatest performance gain (or loss) is realized. Switching to a tuned exhaust system can increase actual HP by 10-20% with this engine. The tuned system must be matched to the aircraft/engine/application/prop and can be optimized with everything considered. It also represents a "bolt on" solution with no other changes to the engine. Additionally, the nature of the tuned system provides a proper balance of backpressure for the engine - this is essentail to proper fuel delivery.
Tweeking the engine, messing with port timing, changing head shims, increasing fuel nitro, even swapping the carb can gain some performance, but often at the expense of reliability if not done properly and with due consideration of the intended use. And in most cases, the gain here is limited compaired to the gain that can be realized from a tuned exhaust system.
Bob