Thanks

Here goes. I've always been a OS guy since i've started racing nitro, however, i have admired the RB C6 also. So i had the opportunity to buy a C6 USA and a 192/2045 pipe combo for next to nothing but needed rebuilt and i'm off to the races. Bought a new p/s/r and ceramic bearings and sent it straight to Uriah for a mod job. Engine broke in well and ran like a top during break in and the 1st 2 races. Then performance started to wain and tune consistancy was non existant. This engine will run stellar for 5 min then abrupty change and go from mildly rich on the bottom to very lean and racey. After shutting it down after a run it sizzles inside like bacon frying. The best i can tell the head is supposed to use a .2mm (.008") and a .1mm
(.004"). I tried the 2045 pipe with the stock rb carb 1st, then put my fms carb and a 9853/41005 and lastly put a fresh speed carb and tried the 9886/41021 combo. I use OS plugs only and have tried a P3, P4, P5 and a P6. I know the potential of this engine as i have seen Murnan modded B9's run before and this is supposed to be slightly stronger on the bottom. If anybody that knows positively what the shimming should be with the rody head button this engine has i would greatly appreciate it. My next move is a conventional head button and for Gods sake i guess some lucky 7. Chris Peralta gave me the ballpark carb settings for this engine a while ago but mine won't come close to functioning with those settings.
Thanks, Rob.

Try using a o,donnell or RB Glow plug. RB,s don,t run good with os glow plugs. Shimming is one .2 shim and 2 .1 shims.

Thanks, i knew the shimming was off. Which rb plug do you recommend? I'm not a fan of od plugs, i find them way too hot but my experience with them is nil.

i run a #100 o donnell plug is a meduim heat plug just dont run the bottom or top needle too rich because they wont last .

they give you a great idle though and starts the engine up quick also
i have a rb s5 by the way on my truggy.


oh nevermind i think the c6 uses tubro plugs.

Hey, its Paul sent you a pm

RB #6 turbo plug

Id run an rb #6 or #7 depending on how hot it is

if you continue to have trouble send me a pm. i had some trouble with mine when i got it

Thanks Tix. Is the #6 cooler than the #7? Do you know for sure the shimming is 1 .2mm and 2 .1mm's? Which i guess a pair of .2mm shims will do the same job.

#6 is cooler than a #7

You can run an odonnell 97 plug, they work well with rbs, rb 6or7 is a good choice also, stay with stock shimming, it sounds like your having carb leaks, try to pick up the newer style rb carb, with the idle adjusting screw on top, the rb buggy 9, or a shark, the older style has the idle screws on the bottom side. Go back with the rb 2045/192 pipe, others tend to run hotter, and less fuel efficient. I have had rbs modded, had better performance and longevity with non-modded rbs.

The lower the number, the hotter the plug, 6 is hotter than a 7.

ok yah The #6 is hotter than #7.

i run a total of .3 of shims

the OD97 plugs work very well in this motor but if RB plugs are available run them
if its over 80 degrees out run a #7. i always run #7's but a #6 will be easier to tune

Mine sizzles inside with .3 shims. Just tried that today. I must have an airleak.