Hi i have 2 questions,easy ones just would like others advise
12-07-2008, 04:54 PM
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Hi i have 2 questions,easy ones just would like others advise
I have a T-MAXX 2.5 and live in NY.Well i thought about taking her out and run a tank,but it's like 17 degrees here.1 Q should i run it a bit leaner? 2nd it's a 3.3 chasis with a 2.5 engine.Now the 2.5 runs great,the lhs guy said why bother putting a 33 in it if the 2.5 works fine? Do you agree? I tell ya it does make sense why change the engine to a 33 when it's fine.I know it will have a lot more torque with a 3.3 but it's still pretty quik.
12-07-2008, 05:39 PM
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RE: Hi i have 2 questions,easy ones just would like others advise
Exactly why fix something that isnt borken? Engines especially as they are qwfully expensive and after you take it out you wont wanna put it back in...
As for the cold, 17 degrees is like unbelievably cold, down here in Houston we might get into the thirties a few times the entire year, and thats at night!
I've always leaned out my engine when its cold (cold her being like 45-60 from 80-90), just because it seems like the logical thing to do...cold weather means your engine is gonna have to be leaner to generate the heat lost to the weather...(I've heard to richen your engine due to the higher density of the air in colder weather, but this never worked for me, my engine just never got hot enough)
Since you are in a bit of a different circumstance though (17 is really really cold) I've heard of using some foil to wrap the bottom to top of the engine head in (but dont cover the top), this holds in heat and lets you engine operate at a safe temperature, it may require a little tuning though
As for the cold, 17 degrees is like unbelievably cold, down here in Houston we might get into the thirties a few times the entire year, and thats at night!
I've always leaned out my engine when its cold (cold her being like 45-60 from 80-90), just because it seems like the logical thing to do...cold weather means your engine is gonna have to be leaner to generate the heat lost to the weather...(I've heard to richen your engine due to the higher density of the air in colder weather, but this never worked for me, my engine just never got hot enough)
Since you are in a bit of a different circumstance though (17 is really really cold) I've heard of using some foil to wrap the bottom to top of the engine head in (but dont cover the top), this holds in heat and lets you engine operate at a safe temperature, it may require a little tuning though
12-07-2008, 06:37 PM
#3
RE: Hi i have 2 questions,easy ones just would like others advise
You richen for colder weather, I honestly wont bother to explain why,but here a great explanation... Also, if you really have money to blow, then go ahead. But if you were smart about it, you'd go for a better engine such as an O.S./RB/Sirio/Picco. No point in "upgrading" to a 3.3 for a tiny increase in performance with similar tuning problems from your classic TRX carbs.
Temperature. Hot weather requires a leaner mixture setting; cold weather requires a richer setting. Most people assume the opposite because they treat the mixture needle like a thermostat. It is wrong to assume that colder weather requires a leaner setting to keep heat in the engine and vice versa. Cold air is denser than hot air. The denser, colder air packs more oxygen into the engine, so going from hot weather to cold needs a commensurate increase of fuel to balance ratio of fuel-burning oxygen and the fuel itself. The opposite is true in hotter weather. Going from cold to hot weather requires a leaner mixture setting.
Tom.
Temperature. Hot weather requires a leaner mixture setting; cold weather requires a richer setting. Most people assume the opposite because they treat the mixture needle like a thermostat. It is wrong to assume that colder weather requires a leaner setting to keep heat in the engine and vice versa. Cold air is denser than hot air. The denser, colder air packs more oxygen into the engine, so going from hot weather to cold needs a commensurate increase of fuel to balance ratio of fuel-burning oxygen and the fuel itself. The opposite is true in hotter weather. Going from cold to hot weather requires a leaner mixture setting.
Tom.
12-07-2008, 07:28 PM
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RE: Hi i have 2 questions,easy ones just would like others advise
ORIGINAL: rcnitrohead
You richen for colder weather, I honestly wont bother to explain why,but here a great explanation... Also, if you really have money to blow, then go ahead. But if you were smart about it, you'd go for a better engine such as an O.S./RB/Sirio/Picco. No point in "upgrading" to a 3.3 for a tiny increase in performance with similar tuning problems from your classic TRX carbs.
Temperature. Hot weather requires a leaner mixture setting; cold weather requires a richer setting. Most people assume the opposite because they treat the mixture needle like a thermostat. It is wrong to assume that colder weather requires a leaner setting to keep heat in the engine and vice versa. Cold air is denser than hot air. The denser, colder air packs more oxygen into the engine, so going from hot weather to cold needs a commensurate increase of fuel to balance ratio of fuel-burning oxygen and the fuel itself. The opposite is true in hotter weather. Going from cold to hot weather requires a leaner mixture setting.
Tom.
You richen for colder weather, I honestly wont bother to explain why,but here a great explanation... Also, if you really have money to blow, then go ahead. But if you were smart about it, you'd go for a better engine such as an O.S./RB/Sirio/Picco. No point in "upgrading" to a 3.3 for a tiny increase in performance with similar tuning problems from your classic TRX carbs.
Temperature. Hot weather requires a leaner mixture setting; cold weather requires a richer setting. Most people assume the opposite because they treat the mixture needle like a thermostat. It is wrong to assume that colder weather requires a leaner setting to keep heat in the engine and vice versa. Cold air is denser than hot air. The denser, colder air packs more oxygen into the engine, so going from hot weather to cold needs a commensurate increase of fuel to balance ratio of fuel-burning oxygen and the fuel itself. The opposite is true in hotter weather. Going from cold to hot weather requires a leaner mixture setting.
Tom.
like said above, you need to richen ur engine, if u lean it ur in trouble
12-07-2008, 07:44 PM
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RE: Hi i have 2 questions,easy ones just would like others advise
So i figure turn all the way in clock wise (top end needle) then back out about 4 counter clock wise.See cause i have it set at 2 and a 1/4 backed out.
12-07-2008, 07:46 PM
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RE: Hi i have 2 questions,easy ones just would like others advise
Above is correct.. Cold air is more dense, more oxygen density than hot air, more air requires more fuel.. In the summer it is common for people to think that they need to richen the mixture when it is really humid because the air "feels more dense".. Humid air is actually less dense O2 wise, and will require you to lean your mixture a bit..
12-07-2008, 08:01 PM
#7
RE: Hi i have 2 questions,easy ones just would like others advise
I don't "see" why you should turn all the way in[sm=confused.gif] or re-tune to factory settings. If your engine was running fine in warmer temps, set both needles counter-clockwise by a quarter to half turn and tune from there. When I fired up my STS .30, the last time I used it was in 70 degree temps, I attempted to use it next in 40 degree temps. As a precautionary measure before starting, I richened both needles as mentioned above, and that was a fine baseline but I ended up leaning it back out a tiny bit anyway.
BTW- Your truck is lovely, but maybe not lovely enough to be posting a pic of it in every post?
Tom.
BTW- Your truck is lovely, but maybe not lovely enough to be posting a pic of it in every post?
Tom.
12-07-2008, 08:13 PM
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RE: Hi i have 2 questions,easy ones just would like others advise
The reason i turn all the way in before backing out is so i know exactly where i'm set.I do apologize if you don't like the picture of my MAXX[&o]
12-09-2008, 03:13 PM
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RE: Hi i have 2 questions,easy ones just would like others advise
How do you do this on a revo 3.3 going from cold to hot weather requires a leaner mixture setting
and going from hot weather to cold needs a commensurate increase of fuel to balance ratio of fuel-burning oxygen and the fuel itself
and going from hot weather to cold needs a commensurate increase of fuel to balance ratio of fuel-burning oxygen and the fuel itself
