Originally Posted by Lonestar

Hurray!!! My N21R outputs the expected low and top-end performance, now it's shimmed at 0.7mm (for 25%). It's still a bit lower than I'd really wish on torque, but top rpm is in the upper quintile I'd say (086HS pipe). Initially I tried to make it work with a #6 Nova, but I just couldn't get it right, it would still overheat, then I went to Odo77 and suddenly it woke up and started being consistent. No flameouts, despite a slightly rich LSN to protect temps.

Now if I could only go past 8:30 runtime I'd feel even better ( I don't think the LSN can add more than say half a minute). If I have time I'll try to put the 9901+41030 back on it to see if runtime picks up.

Thanks all for the help - Sunday is raceday, nothing feels better than beating $450 mills with a $150 one, I'll let you know how it goes

Paul

Originally Posted by cordarrow

They work...but they're super hard. I've chipped more than one Hudy on tight head screws...it was a tuning tool, after all.

Can't beat a good fitting Crapsman for head screws...find one with the perfect blade thickness...then remove the girth for a perfect fit in your heads counter bore...

Originally Posted by cordarrow

They work...but they're super hard. I've chipped more than one Hudy on tight head screws...it was a tuning tool, after all.

Can't beat a good fitting Crapsman for head screws...find one with the perfect blade thickness...then remove the girth for a perfect fit in your heads counter bore...

Originally Posted by rotarynut

Monty, have a question, are the head screws on the FMS 3.5mm 0.6 x 18mm long? I want to put on some allen head screws, I'm not too fond of flat heads,know what I mean! I already replaced the ones on the back plate.
the FMS is running good, just under 1 gal thru it now, thanks man.

Originally Posted by houston

the crank is still a sport crank

9901ss/41005 would be better in the buggy if you are going to use the 9901ss pipe . the 086hs pipe is awesome but does not promote great runtime , great power , a lil violent powerband and crazy top , works awesome on the n21r limited

Originally Posted by Lonestar

Fair enough, still a sport mill after all

I unfortunately don't have 41005... and i'm not planning to buy more bits to make this baby work I have a 41052 in my boxes though but I think that might promote top-end a bit too much (And a pallet of 41021 and 41030). I run an mbx-6, so not everything fits without physically touching the body/tank/sideskirts...

Are the 9901ss's internals different from the 9901's?

Thanks for all the info - I'll dedicate you my victory sunday

Paul

Originally Posted by houston

Pipes aren't necessarily different internally but they do perform different .

Originally Posted by houston

41052?
9901ss/41005 pipeset works on almost all novamills

Originally Posted by houston

your carburetor is just out of balance and you should try to run the 41021 header on the truggy with that engine . everything else seems ok , odonnell 97t plug

Originally Posted by Tricky

Thanks for the help! I ended up changing the plug (97t) and richening up the bottom end quite a bit and it ran fine..no more flat mid range. I'll swap the 41005 with a 41021 that I have on by buggy. So the 9901/41005 will be a good combo in a buggy?

Thanks again!

Originally Posted by Lonestar

really??? same geometry, working differently? Materials vibrate differently to acoustic waves, maybe?

thickness of the wall on an exhaust plays a large part of the way it works yes, the new pipe is probably a touch less volume but it definitely runs better handsdown

41052 isn't a nova ref, sorry - it's a JP Racing (not Jammin Product) rebadgeing of an original nova pipe whose ref I can't find - here's a pic:



tried that style of header before and for some reason it just never felt right , just felt wrong

I bought it last year like a week before nova released the 41030 as I didn't want to melt a second tank with the "stock" 41021

41005 - the one with both 90deg angles??? that header works killer on the buggy with the 9901ss

thanks for all the help

Paul

Originally Posted by houston

why do you feel that you need to disassemble the engine thats my first question , tonys screwz is the screw company that offers replacements i believe . i am pretty sure they are 3.5mm but for some reason i am thinking they 3.75mm

i have had a hudy driver for the heads and have torqued and untorqued 1,000's and 1,000's of those flat head screws with no issues

Originally Posted by rotarynut

Monty, it's just a personal thing against flat heads, I'm an auto tech and disassembly and reassembly is in my blood I'm doing it mostly for inspection purposes. my calipers measured the screws at
3.4 and change so 3.5 has to be it. yeap I just checked @ tony's screws
3.5mm , the kit to do the complete engine is $5.