Although I don't disagree with your points (I never did) I have found that my experience has found the opposite of what the engineering theories have stated..

Lean burn engines were popular in the 80's, running at about 15:1 on normally aspirated cars at part throttle driving, understand most were either rudamentary fuel systems, early EFI or carbs, but they mostly used closed loop feedback, and most did have a high rate of failure at a fairly low mileage...

Again, I won't say that those AFR's will produce less power, or they don't produce the most power, but they do involve the most risk to the engine, it puts you on a threshold of detonation where, in the real world, you would produce knock counts often enough to constantly retard timing and force the AFR's to go richer in a reactive method, not proactive.. What that ultimately means is by tuning more conservatively, you will produce more power more consistently.. The one point about the 12:5-13:1 AFR that is generally true is to produce the most power, you need to get as close to a complete combustion as possible to produce expanding gasses on the downstroke, the small amount of extra fuel left continues to burn on the downstroke producing more expanding gases and more power than a stoich mixture..

Tuning is Proactive, Knock detection and control is Reactive.. a reactive approach will generally yield less power simply because it has to protect from knock in the only way it knows how..


Tuning is about a balance.. Honestly both points are correct, but the theory doesn't always match the practice simply because real world conditions require you to involve safety and longevity..

 

Oh and Fwiw, I think I found the closed loop target table... I have to test the theory soon..

 

I do think you misunderstood the original authors point though.. Which is, that his more conservative tune produced more power, because the knock control and octane number had less activity to react against than the more aggressive tune.

 

Hooray...Please keep us posted. If I can get my car to cruise @ 15.2:1 w/o knock, then the gas mileage gain could be substantial.

 

subscribed for the read...on timing etc.

WADAD

 

I guess your reading comprehension skills are not that great, eh?

I'm not paying him to email me. I'm paying him for a base flash that I'm sure he has done hundreds of times for my set of mods. I'm paying him for what he has found out that works for my mods. For a tune that WILL gain some power for me. Albeit not as much power as a custom tune.

I'll say it again - he is the only tuner that I know of that will email a base flash instead of requiring you to send your ecu in.

Some of us don't want the downtime with our cars. PERIOD.

 

Again, how long have you been tuning a a daily driven, not in a vacumn tube 4G63T?

I'm not challenging you or starting a pissing contest, I am just curious.

 

With ECU flash out I dont see how people can pay for a base flash, custom tune of course, base flash no point. Stock map is very rich and conservative on fuel and timing. It is so rich that if you set boost at 20-21psi with no taper it will still show rich on a wideband without adjustment (self tested various times). You can also add a few degrees of timing in boost portion and it will still be conservative and you can guarantee yourself +20hp also. It wont be optimal of course because it is not a custom tune(recommended), but I guarantee it will feel much better than stock just like people claim on the base flash and you can do it yourself for free or for just the cost of the tactrix cable to support ecuflash.. I hate the fact that someone can take advantage of freeware for some bs like a base flash which does not incorporate any skill. Custom tuning flash by all means is worthy of payment since the tuner is actually putting their skills to use.

 

Why do you want to make this about me? This is NOT about me. This is about a different tuning school of thought that a certain automotive engineer by the name of Klaus Almendinger adheres to.

If you have a problem with what he says, then go to the Innovate forums and tell him that he is full of crap and that what he says does NOT apply to high boost turbo applications like the 4g63. Go ahead and do that. Since you obviously know more than he does, go ahead and debate him. Please provide us with a link so we can watch from the sideline. I have my ready.

 

All I am saying is tune your car and see what works before going by gospel. Just because it's written by somebody else doesn't mean it will work on your car that you drive around all day.

Do you understand what kind of timing and boost you would have to use to run 12.5 - 13.1 AFR on 91-93 pump gas every day, in all different weather conditions with no problems? Have you personally sat on a dyno and tuned for these AFRS? I have.

I'm not arguring that it could very well make the best power at all, he is correct. Everything being constant all the time, knock yourself out.

 

Actually I am tuning my own car and I am following what Klaus is saying. This is my latest:

https://www.evolutionm.net/forums/sh...&postcount=186

taken from this 13 page thread that I created.

https://www.evolutionm.net/forums/sh...1&page=1&pp=15

And once I can find a Defi D EGT gauge, I am going to lean to 12:1. Thne I am going to create a listening device to listen for knock and take the car to the dyno and work my way to 12.5:1.

And for the millionth time, I am running 93.xx octane. I will try my best not to put that 91 crap in my car ever again. After I started mixing my own gas and getting 93 octane all the blown out spraks that I was logging as spikes in my AFR went away. The AFR is smooth, the car idles better and fells better. It is only $12 per tank more. No big deal at all.

 

Good. I commented in the thread.

 

Why would you wanna run 12:1 though when cars run just fine in the 11afr's. I mean lets say the max hp you gain by running 12.1 vs 11.7 afr is 2hp, then you say is 2hp worth the larger margin of safety. All I can say is good luck in your trials.

 

The Vishnu off the shelf maps run at 12.5:1 AFR in 3rd gear WOT. People are downloading them and using them all the time. There is a guy in Honduras who uses the V330+ and he is kicking the *** of M3 Dinan and E55 AMG drag racing. He has had zero problems. Chronohunter uses the off the shelf maps on the road course while using 91 octane gas and he has had zero problems.

It can be done. It is just a different way of tuning. It is based around timing retard and boost reduction and hitting the 12.5:1 AFR. As long as your EGTs are in chekc and you are not knocking, then what is the harm in running effeciently?

 

That's interesting, all the Vishnu cars I have logged or retuned don't run 12.5:1. Are we talking at the onset of boost or through the whole 3rd gear?

I also don't see anything majorly different in boost or timing retard compared to others.

Just curious, where is your wideband probe located?

EDIT: I just tried to find all the "Tales from the dyno" postings Shiv has posted in the past but all the dyno sheets with AFRS have been moved or deleted. I know most of those did not show 12.5AFRs. Unfortunatly they are all gone now.