Ideal Afr For 400Kw+

[trbo 6]

Would it be the fact the the Air fuel gauge is reading lambda 1 at 14.7:1 still and hasn't been calibrated to show lamda 1 as 9.7? So the reading in my case of 11.5:1 is actually 0.78 lambda which is actually 7.56:1.

[rednose]

  On 03/02/2013 at 8:54 PM, trbo 6 said:

Would it be the fact the the Air fuel gauge is reading lambda 1 at 14.7:1 still and hasn't been calibrated to show lamda 1 as 9.7? So the reading in my case of 11.5:1 is actually 0.78 lambda which is actually 7.56:1.

Still on the rich side, which means it should be running cooler.

Just ask Spiro to show you as it would be logged with your power run.

[ratter]

  On 03/02/2013 at 10:55 AM, djqc said:

I have an in cabin oil temp gauge, using the f6 cluster. It has defienitly raised in temp since the tune was done. 430kw on a stock motor is really leaning on it, isn't it? Is 12.8 too lean in my application?

the extra power is probably the main factor in what is elevating your oil temp, plus combined with extra heat through the intercooler etc etc

  On 03/02/2013 at 11:18 AM, IH8TOADS said:

Without sounding like a rude dick....you really need to be talking to who ever did the work.

Obviously they think its safe, so have a chat with them and I'm sure they will give you some confidence.

Other option is to do a high speed run on a private road with a portable AFR meter / data logger after the car has been running for a bit....see what it actually is and present the information to your workshop for their analysis.

Exactly, talking to your tuner should have been your first priority if you had a concern about their work

  On 03/02/2013 at 11:21 AM, xr6t_ute said:

Mick would you tune a 430rwk falcon turbo on 98 octane with 12.8 air fuel ratio on a standard engine??

I normally tune richer than this, but this is not to say my way is correct and I have voiced my concerns to several people in the past about pushing 400 rwkw on standard engines

  On 03/02/2013 at 8:54 PM, trbo 6 said:

Would it be the fact the the Air fuel gauge is reading lambda 1 at 14.7:1 still and hasn't been calibrated to show lamda 1 as 9.7? So the reading in my case of 11.5:1 is actually 0.78 lambda which is actually 7.56:1.

when talking lambda, no calibration is required, stoich is stoich, no matter what fuel is used

[trbo 6]

I understand that stoich is stoich, however e85 has a stoichiometric value of approximately 9.7:1 and pump fuel is 14.7:1, so if a gauge is setup to read stoich at 14.7 as 1 lambda then 0.8 lambda is 11.76, however if the gauge was setup to read 1 lambda as 9.7 for e85 then 0.8 lambda would be 7.76. I know there are a few gauges that you can change the stoich value to account for e85. I'm now assuming that the tuners would not adjust the gauge and leave the stoich value at 14.7:1, so the OP's reading of 12.8:1 would be 0.87 lamda which is 8.439:1.

[ratter]

no adjustments required if talking lambda

[rednose]

  On 03/02/2013 at 11:36 PM, trbo 6 said:

I understand that stoich is stoich, however e85 has a stoichiometric value of approximately 9.7:1 and pump fuel is 14.7:1, so if a gauge is setup to read stoich at 14.7 as 1 lambda then 0.8 lambda is 11.76, however if the gauge was setup to read 1 lambda as 9.7 for e85 then 0.8 lambda would be 7.76. I know there are a few gauges that you can change the stoich value to account for e85. I'm now assuming that the tuners would not adjust the gauge and leave the stoich value at 14.7:1, so the OP's reading of 12.8:1 would be 0.87 lamda which is 8.439:1.

You should be able to figure out how the gauge is setup on idle. Mine shows 14.7 - 14.9 on idle.

[trbo 6]

  On 03/02/2013 at 11:45 PM, ratter said:

no adjustments required if talking lambda

Yep, get it now. I just got worried when I saw 11.5:1 on dyno sheet as I was thinking this should be about 8:1. If I had the print out in lambda there would be no confuson.

Thanks.

Edited 04/02/13 12:00 AM by trbo 6

[ratter]

no worries mate, lambda is easy as fuel type does not affect it