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Lean or Rich!?

Old 08-24-2008, 06:29 PM
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JonKBMW
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Default Lean or Rich!?

Having trouble dialing the car in. Its an HPI RS4 3 EVO+.

If I cruise around it runs good. However, if I floor the throttle it bogs and it doesn't stall it just doesn't go anywhere. I have seen smoke coming off the cooling head, which to me sounds like its lean, but I am not positive, as smoke could come off the head at 220 or 250F, so its hard to say with all the oil and fuel that gets on it. What are the symptoms of lean WOT and rich WOT? I think this is rich, as I would think lean would haul ass and sputter, this kind of sputters and doesn't really want to go anywhere... though I don't see it pouring smoke out either. It puts a good amount of smoke out at lower engine speeds though.
Old 08-24-2008, 06:45 PM
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tonykalil
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Default RE: Lean or Rich!?

Smoke coming off the cooling head would tell me that the plug is loose, or one of the head bolts is loose. This would cause a loss of power, and a tendency not not remain in tune at different rpms. I could be completely wrong, but I have never had smoke come from the head unless it was leaking. I hope this helps,
Anthony
Old 08-24-2008, 06:54 PM
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JonKBMW
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Default RE: Lean or Rich!?

My exhaust header fell off a couple times and I got fuel/oil all over the car. Its likely that burning off once it gets hot. I don't believe the plug is loose or the head is loose.
Old 08-25-2008, 02:56 AM
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Default RE: Lean or Rich!?

If the whole engine is covered in fuel oil, then yes, that's why it's smoking... Lean off the high speed needle a bit and run around some more. Don't let temps get over 280F.
Old 08-25-2008, 04:27 AM
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Default RE: Lean or Rich!?

If fuel is allover the head then smoke is normal and you should not worry. Have you finished break in? If it doesn't stall when at full throtle but just don't acceleratelike you say I believe it is too rich. I guess that the engine is running with factory settings right? Preset is rich in order to have a proper break in process. Break in and then readjust the needles according to your needs.
Old 08-25-2008, 10:02 AM
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oneofakindtrini
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Default RE: Lean or Rich!?

if your car is running at temps of 240F and over you are damaging your engine internals.. a useful tool for you to have would be a temp gun which would help you with tuning..
Old 08-25-2008, 11:57 AM
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Default RE: Lean or Rich!?

No way man, permanent damage won't occur until 290+ is sustained for more than a few minutes. 240 is barely warmed up!! But it does sound like he may have an air leak, those are high temps for a rich engine spitting fuel, unless maybe the low speed is too lean. []
Old 08-25-2008, 12:04 PM
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Default RE: Lean or Rich!?

id say an air leak aswell..

and as above 240 is just about warmed up, they can reach 290 but i do also belive it depends on clutch set-up, and fuel that is being used.
Tom
Old 08-25-2008, 06:25 PM
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Default RE: Lean or Rich!?

what kind of pipe are you running on the car? because i have the same car and i have a problem similar to yours because i keep blowing the gasket between the header and engine which sounds like whats happening to you because of all of the fuel over car. i would check to see if this may be the problem that your having
Old 08-25-2008, 06:34 PM
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JonKBMW
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Default RE: Lean or Rich!?

It had blown that gasket because the bolts backed out. I now have socket cap bolts holding the header on with lock nuts as well.
Old 08-25-2008, 08:30 PM
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hpiigt2
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Default RE: Lean or Rich!?

Yeah i keep having trouble with my gasket i just blew another one today which is probly close to the tenth or more ive blown. the problem with the hpi gaskets is that they are just thin paper and that running rich makes the gasket blow so ive been trying to find a solution to fix my problem
Old 08-25-2008, 08:45 PM
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JonKBMW
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Default RE: Lean or Rich!?

The only real important shape to the gasket is the port for the head. Ever consider punching some out of thin copper sheet?
Old 08-25-2008, 09:19 PM
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Default RE: Lean or Rich!?

that would make sense it would be stronger.. would that be able to stand the heat and would it be worth it..
Old 08-25-2008, 10:02 PM
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Default RE: Lean or Rich!?

could definitely withstand the heat
Old 08-26-2008, 08:33 AM
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Default RE: Lean or Rich!?


ORIGINAL: Foxy

No way man, permanent damage won't occur until 290+ is sustained for more than a few minutes. 240 is barely warmed up!! But it does sound like he may have an air leak, those are high temps for a rich engine spitting fuel, unless maybe the low speed is too lean. []
foxy i dont mean anything bad, but rs4 3 evo the T3.0 is supposed to run at around 220f.. so how can 240 be warmin up.. lol. and another thing can a engine even run at 290f. the will be like nearly no fuel in engine. so is it possible to even start the car with so little fuel in the engine..
Old 08-29-2008, 07:44 PM
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Default RE: Lean or Rich!?


ORIGINAL: hpiigt2

Yeah i keep having trouble with my gasket i just blew another one today which is probly close to the tenth or more ive blown. the problem with the hpi gaskets is that they are just thin paper and that running rich makes the gasket blow so ive been trying to find a solution to fix my problem
I blew the header gasket out of mine the first run after break in. I found that a Hi Temp silicone works great to seal things up. I used on my leaking backplate as well. If you apply it right you should have leak free running for quite some time. The silicone can be puchaseed at most stores or auto stores.
Old 08-30-2008, 02:50 AM
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Default RE: Lean or Rich!?


ORIGINAL: trini4life


ORIGINAL: Foxy

No way man, permanent damage won't occur until 290+ is sustained for more than a few minutes. 240 is barely warmed up!! But it does sound like he may have an air leak, those are high temps for a rich engine spitting fuel, unless maybe the low speed is too lean. []
foxy i dont mean anything bad, but rs4 3 evo the T3.0 is supposed to run at around 220f.. so how can 240 be warmin up.. lol. and another thing can a engine even run at 290f. the will be like nearly no fuel in engine. so is it possible to even start the car with so little fuel in the engine..
220 is barely warmed up. You have to get these engines over 200 just to get the piston and sleeve expanding properly. Believe me, after qualifying hard, you may see temps over 280. I've had em over 300, of course the engines still work. Over 300 is not good but up to 290 is fine, as long as it isn't sustained for too long. I'd say 260 is your optimal average temp.

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