Wow, the piston was completely out from the sleeve, as long as the piston n sleeve have no scratches is good to be pinch

Oh I just have the piston sitting ontop of the sleeve so I can get a good shot of it, it will go a little above the line in the piston

Damn what fuel do you run? Thing looks filthy. Not necessarily bad but nasty

Looks fine for a repinch. Send it to Rayaracing and ask for the firm/international pinch, it lasts the longest, it'll be just like a new engine.
But remember to replace both front and rear bearing, if you want it to last.

I'm running Punch 30% fuel, most people use that fuel at our track, thanks for the help guys, I'll get it all cleaned up.

Jato man where do you race?
Cory drachenburg has one of rayaracings tools for repinching in edmonton rcdepot.ca

Yeah I race in Edmonton with Cory, dang god racer too.. I've just got it pinched last night so all seems perfect now. I didn't know Cory did pinches. Thanks.

That pinch should do the trick for a while. Probably was a better option than buying a whole new piston/sleeve which isn't cheap. It might also be a good idea to replace the conrod next time it needs a pinch assuming the crankpin is still in good shape. As cheap as you can get some of these Nova engines now it doesn't really pay to stick a ton of money in replacement parts into them imho.

I'll be racing with you guys Saturday look for an orange and white kyosho buggy with no stickers and nova motor and say hello.
Yeah Cory is quick he made the 40+ a main at either the nitro challenge or silver state

Switched from 20% to 30%
 

Ok guys,
What are the stock carb setting for the Rex 21 and p5xlt?

While I know the saying if it isn't broke don't mess with it. I messed with it. Both engines were running just fine when I accidentally grabbed a gallon of 20%. No flame outs, decent power, not real snappy but ok. Well after the gallon ran dry I went back to 30%.
Now they are both acting boggy down low, but good mid and high. I've considered both lean bogged, and rich but in the process I think have gotten too far off on my needle settings.

The high speed needle is 3.5 turns and the low speed needle is 5 turns they are for the p5xlt and it might work for the rex 21

Thanks...Those numbers got the rex back to a tunable state. I have not gotten a chance to get the p5 going.

set the p5 flush on high speed and flush on low speed. Pretty much what I do on any Nova engine when tune gets out of whack.

Your welcome

9901/41021
 

Guys, need an honest opinion, i have had this combo on 4btt/4bttwc/keep off4/paloma/keep off7, felt like the powerband is so restrictive n unproductive,just for fuel economy i would say. Much better with 2096/41021/41033.to wake it up I'll run 9886 or efra 2058.