question about pe

[200gmc]

am been trying to tune my car maf, ve, and wot. i went ahead and changed stoich to 14.13 since the pumps e10, ok so i want to change my pe values but should i multiply by 14.13 or 14.69.

[mowton]

PE is PE reardless of Stoich.

Remember, to tune PE (WOT) you set the PE EQ to a value across the board (say 12.8) and with a wideband (only way to do it right) change your MAF and/or VE (whatever fueling mode you are tuning) values to match your commanded AFR (12.8) similar as you would do in stoich.

Once done, you can push your PE value around without having to retune.

Hope this helps

Ed M

[200gmc]

PE is PE reardless of Stoich.

Remember, to tune PE (WOT) you set the PE EQ to a value across the board (say 12.8) and with a wideband (only way to do it right) change your MAF and/or VE (whatever fueling mode you are tuning) values to match your commanded AFR (12.8) similar as you would do in stoich.

Once done, you can push your PE value around without having to retune.

Hope this helps

Ed M

well right now am tuning in close loop,but since i have stoich at 14.13 my values for pe would be 1.10, is that correct, or my values would come off 14.69 that it would be 1.14.

[mowton]

well right now am tuning in close loop,but since i have stoich at 14.13 my values for pe would be 1.10, is that correct, or my values would come off 14.69 that it would be 1.14.

Yes to the first assumption. If you are running E10 gas, then stoich will be around 14.2/14.13 (Lambda 1.0) as you stated. To this setting the PE EQ to 1.11/1.10 will put you very close to the 12.8 (lambda .90) desired AFR from my previous post.

Ed M

[ALB]

This whole think is still pretty confusing. I don't think you want to run e10 at 12.8 for na since would think best power for e10 is to be found at 12.3 .?

[mowton]

This whole think is still pretty confusing. I don't think you want to run e10 at 12.8 for na since would think best power for e10 is to be found at 12.3 .?

My 12.8 was just an example. I also stated above that getting the tuning accomplished with one value would allow you to modify the PE value as needed.

The question, I thought was more based on how to derive the PE based on Stoich, then what would generate the most power. Does that clear up your confusion?

Ed M

[BBA]

Yes to the first assumption. If you are running E10 gas, then stoich will be around 14.2/14.13 (Lambda 1.0) as you stated. To this setting the PE EQ to 1.11/1.10 will put you very close to the 12.8 (lambda .90) desired AFR from my previous post.

Ed M

Why would you want to do that?
Realize you NEED to run richer if you run E10. What you are proposing with the 1.11 PE ratio is running too lean.

Think in terms of LAMBDA, not AFR!

Lambda of .85, where the most power is made, is PE ratio of 1.175, for an E10 AFR of around 12.0, which is definitely better than running with 1.1 PE (Besides, why even have PE at all if you are going that lean?).

[mowton]

I think I missed the objective of this question and over simplified without thinking it through.....sorry

The simple answer is yes but I forgot about the E10 factor realtive to PE and picking the 12.8 in the example. Force of habit....

I agree with BBA and it's easier to work in lambda...just starting to change over . Most Widebands will output 14.7 at Lambda 1 unless re-configured as well.


Sorry again

Ed M