Diffrence between lsn and hsn
06-04-2006 | 08:29 PM
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From: , MD
Diffrence between lsn and hsn
Hello,
Whats the diffrence between the hsn and lsn on my x? On my hpi rs4 i only had 1 needle... But know y do i need 2? what does the lsn do and what does the hsn do? which one should i tune first? How should i tun it? Lol... give me every detail please!!!!!!!!!!
Whats the diffrence between the hsn and lsn on my x? On my hpi rs4 i only had 1 needle... But know y do i need 2? what does the lsn do and what does the hsn do? which one should i tune first? How should i tun it? Lol... give me every detail please!!!!!!!!!!
06-04-2006 | 08:43 PM
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From: Camarillo,
CA
RE: Diffrence between lsn and hsn
The HSN controls fuel mixture at any speed above idle, while the LSN controls fuel at idle speed. You should get the HSN tuned first, before ever touching the LSN. After the LSN is set after break in, you will hardly ever need to touch it, but you will need to tune the HSN during the first run of the day, or anytime when the weather changes significantly.
06-05-2006 | 10:56 AM
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RE: Diffrence between lsn and hsn
The HSN affects fuel delivery into the engine at all rpms....it's the main path for fuel to get into the carb. With that said, in addition, the HSN is used to tune the high speed engine rpm fuel delivery...even though it regulates all fuel coming into the engine, just the way it is. The LSN affects the engine's low speed/ lower mid speed rpm fuel delivery. Adjust the HSN first and then the LSN and finally the idle speed. Simple stuff.
06-05-2006 | 02:34 PM
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From: Macon,
GA
RE: Diffrence between lsn and hsn
ORIGINAL: bumperdragger
The HSN affects fuel delivery into the engine at all rpms....it's the main path for fuel to get into the carb. With that said, in addition, the HSN is used to tune the high speed engine rpm fuel delivery...even though it regulates all fuel coming into the engine, just the way it is. The LSN affects the engine's low speed/ lower mid speed rpm fuel delivery. Adjust the HSN first and then the LSN and finally the idle speed. Simple stuff.
The HSN affects fuel delivery into the engine at all rpms....it's the main path for fuel to get into the carb. With that said, in addition, the HSN is used to tune the high speed engine rpm fuel delivery...even though it regulates all fuel coming into the engine, just the way it is. The LSN affects the engine's low speed/ lower mid speed rpm fuel delivery. Adjust the HSN first and then the LSN and finally the idle speed. Simple stuff.
Good explanation!
Some carburetors all so have a mid range needle as well. Most do not mess with it unless you are a expert tuner.
