Nitro Engine Factory Settings

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kvnnets

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Location
Oakville, Ontario, Canada
I thought this might be a helpful thread for everyone who might have lost a manual or did not receive one when they bought a mill second hand.

Factory Carb Settings

HSN = High Speed Needle
MSN = Mid Speed Needle
LSN = Low Speed Needle (Metering needle)

OS Engines Factory Settings



18TZ series engines
High Speed Needle: 2.5 turns out from fully closed
Metering Needle (low speed): flush with carb or ball link body

18CV series engines
High Speed Needle: 2.5 turns out from fully closed
Metering Needle (low speed): .5 turn in from flush with carb body

21XZ Series engines
High Speed Needle: Approximately 3 turns open from fully closed
Metering Needle: Rotate until slotted head is flush with carb body

21VG Series engines
High Speed Needle: 3 turns out from fully closed
Metering needle (low speed): flush with ball link body

21VZ Series
Depends on the model/version of the engine

21TM Series engines
High Speed Needle: 2-1/2 turns out from close.
Low Speed Needle: 1/2 turn in from flush with carb body.

28XZ engines
High Speed Needle: 3 turns out from fully closed
Low Speed Needle: Rotary: flush with carb body
Slide: flush then 1/2 turn in

30VG engines
High Speed Needle: 2 3/4 turns out from fully closed
Low Speed Needle: flush with ball link body, then 1.5 turns in

Novarossi .21 through Novarossi .28
High Speed Needle: 3.5 turns out from seated
Low Speed Needle: 5 turns out from seated
IDLE: 0.6mm

LRP Z.28 Spec 3
High Speed Needle: 3.75 Turns From Closed
Low Speed Needle: 3.75 Turns From Closed
IDLE: Gap between 0.5mm and 1.0mm open

LRPZR .32 Spec 2
Hi needle 5.50 turns open
Mid/Low needle 5.25 turns open
Idle .05 to 1 mm

Mach 427 (lst2 and muggy)
High Speed Needle: 4 turns out from bottom
Low Speed Needle: 2,5 turns out from bottom
IDLE: .5mm - 1mm

SH .28
High Speed Needle: 3 turns out
Low Speed Needle: 3 turns out
IDLE: 1mm open

Ofna/Hyper .21 engine Factory Settings



  • Set the master needle IN until stops, then turn OUT 4.5 to 5 turns.
  • Setting for the black low end needle is OUT 3.5 turns out from flush.
  • Setting brass head mid range needle, should always be flush to the case

Ofna .28
High Speed Needle: 2 1/2 to 3 out
Low Speed Needle: Out 2


Dynamite Platinum .28 (Mach)
High Speed Needle: 3.5 turns out (counterclockwise) from closed.
Low Speed Needle: 2 turns out (counterclockwise) from closed.
IDLE: 1mm gap

STS .21 and STS .30
High Speed Needle: 3 turns out from the end
Low Speed Needle: 4.5 turns out from the end
Idle: 0.5mm open

Force R36
High Speed Needle: 3.5 turns from seated
IDLE: 1mm

I have also read that the factory settings in the manual for both the Picco .21and .28 are way off.
He is a good starting point that most people have had success with.

Picco .21 and Picco .28
High Speed Needle: 7 1/2 - 7 3/4 turns out from seated
Low Speed Needle: 5 1/2 - 5 3/4 turns out from seated
IDLE: 0.5 mm

Losi 3.4
High Speed Needle (HSN): 2.75 out from closed
Low Speed Needle (LSN): 2.75 out from closed

Force .26
High Speed Needle: 3 - 3.5 out from closed
Low Speed Needle: Flush with ball end
IDLE: Set for 1/16th inch gap

Force .28
High Speed Needle: 3 - 3.5 out from closed
Low Speed Needle: Flush with ball end
IDLE: Set for 1/16th inch gap

Force .32
High Speed Needle: 3-3.5 out from closed
Low Speed Needle: Flush with ball end

Losi 454
High Speed Needle: 2.5 out from closed
Low Speed Needle: 2.5 out from closed

Losi 427
High Speed Needle: 2.5 out from closed
Low Speed Needle: 2.5 out from closed

Losi 350
High Speed Needle: 3 out from closed (counter clockwise)
Low Speed Needle: 4 out from closed (counter clockwise)


HPI Nitro Engine Factory Settings



Nitro Star S-25
High Speed Needle (HSN): 4 1/2 Turns From Closed
Low Speed Needle (LSN): 3 Turns From Closed
Idle: About 2mm

F4.6
High Speed Needle: Flush with groove
Low Speed Needle: Flush with case
IDLE: 1 mm

K4.6
High Speed Needle: Flush with groove
Low Speed Needle: Flush with case
IDLE: 1 mm

K5.9
High Speed Needle: Flush with groove
Low Speed Needle: Flush with case
Idle: 1 mm

HPI also recommends not to adjust the mid range needle.


AXIAL Factory Settings



axial-factory-carb-settings.png

32RR-1
High Speed Needle: Flush with carb
Low Speed Needle: Flush with carb

28RR-1
High Speed Needle: Flush with carb
Low Speed Needle: Flush with carb

28 Spec-2
High Speed Needle: Flush with carb
Low Speed Needle: Flush with carb


Traxxas TRX Factory Settings

- For The Traxxas lovers out there :p

TRX 2.5 & TRX 3.3
High Speed Needle: 4 turns out
Low Speed Needle: Flush with valve or 1.5-1.75 turns out
Idle: 0.70-1mm open.

I know there are engines that I missed so feel free to add factory nitro carb settings at will.



Nitro Carb Explained:

rc-nitro-engine-carb.jpg
And if it has a mid speed needle it would be on the opposite side of the lsn, and the side of the aluminum housing... it's typically bad practice to adjust the MSN.
 
quick one whay about the nitro star s 25
 
Losi 3.4
HSN 2.75 out from closed
LSN 2.75 out from closed

Losi 454
HSN 2.5 out from closed
LSN 2.5 out from closed

Force .32
HSN 3-3.5 out from closed
LSN Flush with ball end

There is a discrepancy on the Losi 454 settings, as the manual give the settings I posted above, but from the factory they come at 3.5-4 turns out. I can't remember what mine was when I got it. Also, the manual show a picture of a different carb on the engine, than what most people have with the engine.
 
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axial .28/.32 high is on the line and low is flush and mid is flush
 
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Does anyone know the factory settings for my 4.1 big bore savage?

I have just been given a hpi savage 4.1, and it runs a bit slow, it cant wheelie, and its very hot, can anyone suggest a simple solution to my problems?

I am new to nitro so please make it simple.

Many thanks

Eddie
 
Just tried those settings. It ran like a bag of spanners, so tweeked it a little and it runs a bit better.

Blue smoke at full throttle and some blue smoke at set off.

Still wont pull a wheelie tho!

Am I right to assume that it should wheelie? or would I need a bigger engine?
 
i have the 4.1 engine and it wheelies but not all the time" depends on what tires I'm running and what surface I'm running on",the 4.1 is actually a pretty good engine in my opinion....

P.S.. GREAT THREAD KEVIN!!!! REPS SENT
 
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my 4.1 was running incredibly hot, and I couldnt get it to run cooler, so my mate (he has a thunder tiger mta4) suggested trying the settings on his carb, 2.25 turns out on the main jet, this has transformed my truck performance and its now running MUCH cooler. Still wont get those front wheels up tho!!
 
I have sorted the problem...... The carb was set so it could only acheive 1/4 throttle!! don't know why I didnt notice! maybe I need to get my eyes checked!!

Anyways.... its very fast now and with a bit more tuning the front wheels are getting off the ground.
 
Aloha all,

can someone confirm that the LRP z.28r spec3 factory settings for LSN and HSN are both 3.75 from closed? I just sealed my engine last night and before removing both needles I checked my needle settings and I got for LSN 1.75 and HSN was just under 5 turns from closed. I'm not sure which to go by.

Thanks
ulua
 
if you richen the high speed needle doyle keep turning it until you see a line on the hsn body that is base tune
 
what about a axial .28rr
 

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