The motor I am tuning now idles at around 950 in gear and 1500 out of gear. The cam is huge. About 80 KPA at 950, 55 KPA at 1500. The X-Tau appears to cause a huge hunt for idle speed when on. Is it ok to just zero out all the X-Tau valued below say 1200 RPM Do I need a 1200 cell and a 1250 cell to make the transition fast from zero X-Tau to normal X-Tau. Right now it is reasonable on normal TPSdot only. Do I back some of that off to say half when I turn on X-Tau. This thing get about 5 MPG so...experimenting is a little pricy.
AW
X-Tau and a very big cam
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Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
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whittlebeast
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X-Tau and a very big cam
Sea-Doo 785 running MAF, V3 & Extra
www.v8efi.com Nearly self tuning Holley carburator replacement kit. Coming soon.
www.v8efi.com Nearly self tuning Holley carburator replacement kit. Coming soon.
Andy,
You can' t set tau =0 because the code divides by tau - it will force itau to 1 no matter what you set. 1 is the lowest value. It may be we need a special test to turn tau off if the tau at the rpm, map you are at is set to 0, but I don't know how things will react if you move back and forth between a tau = 0 and tau = 1 situation. If tau = 1 doesn't help, then we may have to experiment - after I solve the flash burn/ wheel decode problem.
As far as reducing tpdot AE when X-tau is on - I suspect a mix of the two will be optimal - that's what lance found. We just don't have anywhere near the data base to say this definitively.
You can' t set tau =0 because the code divides by tau - it will force itau to 1 no matter what you set. 1 is the lowest value. It may be we need a special test to turn tau off if the tau at the rpm, map you are at is set to 0, but I don't know how things will react if you move back and forth between a tau = 0 and tau = 1 situation. If tau = 1 doesn't help, then we may have to experiment - after I solve the flash burn/ wheel decode problem.
As far as reducing tpdot AE when X-tau is on - I suspect a mix of the two will be optimal - that's what lance found. We just don't have anywhere near the data base to say this definitively.
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whittlebeast
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All I know is when I turn on X-Tau the X-Tau gauge hunts back and forth and so does the idle. The table is I think default and the X is set to like 30 Have not realy tried other things as I was fighting a different issue at the time and ....
AW
AW
Sea-Doo 785 running MAF, V3 & Extra
www.v8efi.com Nearly self tuning Holley carburator replacement kit. Coming soon.
www.v8efi.com Nearly self tuning Holley carburator replacement kit. Coming soon.
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whittlebeast
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Is it 1 or .01 that is the lowest that Tau can be set to? The numbers in the table go from about .33 to .01 as I remember.
AW
AW
Sea-Doo 785 running MAF, V3 & Extra
www.v8efi.com Nearly self tuning Holley carburator replacement kit. Coming soon.
www.v8efi.com Nearly self tuning Holley carburator replacement kit. Coming soon.
Andy, I'm sorry I'm used to looking at the code where tau is in secx100 so 1 is .01in MT. Use .01 as the lowest value of tau; you can and should also lower X. I would lower it to 5 or 10 % and lower the taus near idle to .01. If this is still causing problems then I don't think X-tau is going to help in the idle region. If you are basically happy with the tpsdot AE except for maybe 1 or 2 places thaen see if X-tau helps there. If so, then we can try a code mod that will allow a 0 tau to kill any fueling enrichment in the idle region but leave things as they are in the region where it helps..