iv been told that you shouldent put anything bigger than a .18 in a 1/10 scale, but im not sure how realiable the source is, or even who it was, someone on here though. oh man i love the 2 speed. when that engine winds up and shifts into secon it sounds awesome. for some reason on cold days like 20 f or lower the transmition dosent like to shift untill you have ran it for a few minuts. the engine revvs real high until it shifts but then it starts to shift fine. but when it is warmer out i have no problem.

I will what the shaft size for the .21... that the important... Imagine the tork of .21 in 1/10 damn!

lol that should put out alot more power. but remember too loo at how much hp the engine puts out. i saw a .15 that puts out 1.2 hp because it has aggresive porting. mine only has .85!

What speed can you reach?with the 2 speed?

How can we tune our engine to sques more power from them... i guest i've see a forum for that.

well i havent checked it for sure but i can beat my friends four wheeler and it gos about 55-60.

the only way to get any more power by tuning it leaning the high speed needle. but you dont want to go too lean. you are new to this right? how many tanks have you put through your engine? and did you break it in properly?

No am not i know that we can lean high needle but not to much to smoke the engin.

I have head that you can modified some part in the engin .15cx to make it more powerfull. Somewhere on the web

ok maby you can get a airfilter that will allow more air to get in. i think they call them low profile but im not sure. another thing to try is to either take the disk in the muffler out or just drill bigger holes in it. and i would recomend using 20% nitro 16%oil. if your not already.

Already

already what? you got the airfilter and the muffler thing?

oh your already running 20/16?

Yes... 20/16

ok well i just made more holes and a few of the exisiting holes it the disc that is inside the muffler bigger. so im off to run it a little i will tell you how it works in a little while

wow..........man this thing is 10 times better. ok what i did wa drilled about 16 1/64 holes in the disk and some of the holes that were already there i made bigger. man this care must be pushing 65 now. it shifts into second in about 1 second. and it powers to to speed in 4-6 seconds.

i think i might either tak it out or drill bigger holes in it. and it is not really any louder

WOW!!! and if you try without the disc??? Try it

Some of us are eagerly awaiting your results!
(and I am heading out to the garage to start dismantling the muffler!) LOL

ok ill try it in a while but i got the buggy real dirty.[>:] lol so i hade to clean the air filter becaus it was all mud. i really mean all mud. the whole front was litterally caked with like 1/8 inch of mud and it stoped running.

Please!!1 TRY IT!!!

lol, darn i have to wait till my air filter drys. but the disk is out and as soon as it drys im going out to try it.

nooooooooooo. i have to hurry because it is starting to snow!!!!!!!

Put your air filter in the microwave

ok it is dry enough im off!!!!!!!!!!!!!!!!!!

ok i blew my engine[:@]