jefx

I pulled the TT .21 out of the MGT and replaced it with a Mach .26 before ever running it. Recently I took the unused TT .21 and dropped it into my Tmaxx (because it was just laying there) and broke it in. What kind of temps do you guys see from the TT .21 on an average day of bashing? Also, how sensitive are the needles for you guys?

It seems to like to run around 270 in the 10 lb Tmaxx, so I couldn't imagine how hot it would get in a 14 lb MGT. The needles also seem very generous. From my experience with other engines, a 1/8 turn can make a big difference in performance, but a 1/8 turn in a different engine has about the same affect as over 1/4 turn in my TT .21. Is that normal? Are the needles really just not very sensitive in this engine?

Oh, I'm running Eliminator 30% (16% oil) and an MC-9 plug.

ICrashThings

Whoa!!!

Im running at 230 degrees and thats a 1/8 turn above rich. I use 20% bluethunder and OS #8 plug.

Dont know why you are getting such a high number in such a light truck...?

jefx

I know it. I sealed the backplate and carb base before ever breaking it in, and it runs consistantly, so I don't suspect an air leak. This is the first time I've broken in an engine with the heat cycle method as opposed to the idle on a box method. I printed the heat cycle method instructions directly from RB's web site and followed them as closely as I could. The engine runs fine, it's just hot.

Also is it just me, or do the needles seem less sensitive compared to other engines?

fourwheeler

The needles are not sensitive on mine either. I wonder if it was an attempt by TT to make tuning easier. BTW mine likes temps of about 240-250.

jefx

Cool, thanks.

blackrain

needles arent sensitive on mine either i run 30% odonnel with a o.s. 8 plug temps around 230 degrees and it holds its setting. might be your fuel when i ran 30 % sidewinder with the same plug my engine ran a lot hotter. the odonnel ran cooler with better performance.