Thread: A/F ratio and proper tuning ?
11-26-2007, 01:04 AM #1
A/F ratio and proper tuning ?
My main concern for this thread is to get to the bottom of why I'm running lean.(Reason for my exhaust manifold to start melting) It is not really bad but it is melting. I'm currently running 8100 RPM dead on with a stock ecu, a SIII and the 42's. I know that I am not on the limiter, and the 42's should be giving me the proper ammount of fuel for my setup. A few reputable sources have told me not to worry about it and to just keep riding. (Even Stock ski's with low hours have melted manifolds before) I guess what i'm trying to get at is what can be done to dial in the ski to have the proper A/F ratio?
What is the best solution to this or combination to use?
Rude fuel Controller ?
RIVA or Rotax ecu with 50# injectors ?
Rising rate fuel pressure regulator ?
LM 1 A/F gauge ?
11-26-2007, 01:32 AM #2
The only way that you will be able to tell if your problems is from running lean is the LM1 gauge. You would need one to get the Rude fuel controller or the rising rate dialed in correctly. If nothing else you would have the peace of mind knowing exactly what is going on prior to purchasing some of the other items it they are even needed.
11-26-2007, 01:45 PM #3
LM 1 ??'s
How does the LM1 work ?
Is it something that is always connected to the ski ?
Can it be used on more than one ski ?
11-26-2007, 01:50 PM #4
11-26-2007, 01:58 PM #5
Melted Log manifolds
I think every one running an aftermarket intercooler has an exhaust that looks like yours. The damage never seams to get any worse but the long term prognosis for the flex in the J pipe is not good and they are expensive. I use the rad4racing.com exhaust tip and this will never melt. There are other dimensional differences to this tip that eliminate the heat stress on the flexy also.
Even getting your air fuel bang on I think you will still melt a stock manifold tip as you are running higher EGT relevent to the performance gain. A Torque plate helps drop this temp fractionally...there are a few sorts of those around to choose from.
I am interested to hear if turbo users suffer the same situation?
Anyway good luck....at least you are on the track and making more power than stock eh.
11-26-2007, 02:01 PM #6
you have to weld a bung in your J pipe.
its not something you want to leave on the ski all the time due to the moisture rich environment which will reduce the lifespan of the 02 sensor.
11-26-2007, 02:03 PM #7
Forgot to add the pics!
Problem solved....now just that AF to get right.
11-26-2007, 03:07 PM #8
I agree, even with the correct air fuel, the stock tip on the manifold is going to melt. I have looked in the rad one as well as the Friebe1 one. both seem to do about the same. Both illiminating the problem of melting manifolds.
so then, im guessing once you tune the machine and have it where you want it, the LM 1 can be removed and used on another ski and another..., as far as the bung in the j pipe, a bolt to block off the hole and your done ??
11-26-2007, 04:49 PM #9
What about going with a greenhulk waterbox? Anyone have any test results of this waterbox lowering exhaust temps?
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