If all you can get is 30% then just remove the .004" (0.1mm) shim from the engine, and use the set-up Joe posted. Always run the 8mm carb insert.

I'd rather see you leave the stock shimming and just bump up to 40% nitro. So if you race at lower elevations tracks all you would do is use 30% no head adjustments back and forth, only nitro percent adjustment.

JS engines are awesome engines for run time and power. I did 1 pit stop in 20 minute main great engines ED.

the 2041 is what i used in that motor. i got 11 min and great power with EB 30% fuel. here is the link to the pipe.

http://www.amainhobbies.com/product_...ine-Tuned-Pipe

Got a little sale going right now with the Race Prep's! I guess people have forgot that I carry the JS/EB line because the sales have slowed so here is a reminder

As always free shipping on every order large or small!
http://twisted-rc.com/shop/specials.php

I'll be making an order with you soon.

Thank You Ed Bridges and Joe Alessi. Can't wait to place an order my self!

motor is running great! got the box stock motor running with a 97t plug and cold fusion 30% nitro and tried both a 086 pipe and an OS 2050. got a little bit of a problem tho motor runs great all throughout the quals/main but on the longer runs, about 6-8min in, (when the motor really gets good and up to temp) the bottom end really starts to bog down. its got a deep bog for about half a second then it clears out and screams. doesnt seem too lean on top as its temping right around 220-225 and i didnt have a hole lot of time to mess with the bottom end needles. right now the LSN is about 2 o'clock angle flush with the housing not quite sure how many turns it is. i know its not the clutch shoes because they are practically new (and yes they were "broke in")
think it could be clutch springs (they are new too and they are 1.0) are is more than likely a tunning issue
any help is always appreciated

richen the hsn 2 hours, you're close. then set the lsn if needed. remember as the tank empties the tune leans out a bit, when you pit the temp is already up a bit for the second tank, then the third and fourth. then you hit the magic bog temp. had a buddy's stock (which i ended up buying) do it and we messed with the lsn all morning, as soon as we fattened the top a hair it ran flawless.

+1 when the bottom bogs like that its the top being too lean. fatten up 1 hr at a time till it stops, then start leaning on the bottom.

Thanks gys. I appreciate it mucho!!!

guys you are awesome! went back out today motor absolutely ripped. fattened the top about an hour and a little and leaned the bottom 1 hr and man is she screaming now. not even anywhere near broke in yet, got 10min 12sec on a tank in buggy temped at 212 and wicked fast goin down the back straight.

Glad you got the tune worked out, something's wrong in your sig though.

lol yeah i know just havent gotten around to changin it

Gotta say, Thank you Ed for making a great engine. Finely got my new losi truggy out this past weekend. All i can say is wow!! I stayed conservitive with the tune.
Setup:
Byrons 30%, Dyn .86, p5 plug, 8mm carbs insert.

Tyler

my motors where running awsesome at the sweep challenge yesterday. ended up not getting to race truggy though due to a servo failure and i dnf'd in the buggy main due to a clutch bell breaking