Do You Want A Lean OR Rich AFR? | Fuel VS Power!

[@Kj16V]

0.75 = 11.0 AFR 0.86 = 12.6 AFR 0.92 = 13.5 AFR 1.0 = 14.7 AFR 1.15 = 16.9 AFR I pause the video and do the maths so you don't have to :D

[@vteclee7100]

Thank you

[@DP-nr1hz]

I'm not going to base my 800 hp k24 engine based on your YT comments section afr conversion.

[@mrpasciak92]

@@DP-nr1hz for engines running gas these conversions are spot on.

[@MercOilbuner]

What about engines running 10% ethanol?

[@Froggetatts]

Alot more entertaining then the dudes accent

[@hambo6713]

This is, by far, the most impressive explanation (and demonstration!) of AFR tuning that I've ever seen. This channel is the cream of the crop.

[@Spiegel420]

Ohhh yeaaaa

[@chrisveeriah1524]

I absolutley agree. Brilliant.

[@shingnosis]

Agree 100%.

[@Georgianson]

Haltech made similar video many years ago...

[@mr.cangieter8758]

You should try their courses.

[@haydent1000]

You can be rich your whole life but you can only be lean once

[@robocop3961]

Hayden Thompson haha good 1 👍🏻

[@FacesintheStone]

Dammit, you nailed it!

[@Josh-jr1dd]

The exact opposite for a diesel engine though lol

[@TURBODON6]

Don't wash out your cylinder walls

[@damienmikkelsen6056]

Hahahaha that’s AWESOME!

[@mattparker5639]

You explain things so in detail very well done video

[@hpa101]

Thanks Matt!

[@maxtorque2277]

The reason AFR has a greater effect on an engine than demonstrated here is due to the interaction with ignition timing (fixed for your test) especially for engines that are spark limited (ie run into detonation or pre-ignition before they reach maximum BMEP) Had you run your test at an engine speed closer to peak cylinder filling (ie peak torque) chances are, if you had an ignition timing also optimised for max BMEP, the engine would have started to detonate at the lean AFR settings. So, by running richer, the extra evaporative cooling and additional heat absorption of the greater fuel mass, would reduce the temperature of the charge during the compression event, and allow you to run with an earlier ignition point, which results in a higher mass fraction burn at a smaller average chamber volume, and as a result greater energy transfer to the piston, as opposed to it just going out the exhaust (which is why EGTs fall with advanced ignition angle despite peak combustion gas temperature being higher (effectively you get a higher dynamic expansion ratio)

Exactly, I proved what you said many times on a dyno.

[@ArturssonEngineering]

Word to that!

[@ivo3396]

You took the words right out of my mouth...lol...

[@lafrad]

This is secondary: You are using fuel and cooling effects to make up for lack of octane.

[@Georgianson]

I had exactly the same thought. For instance the old good turbocharged 4g63 makes the best power at lambda 0.75 whilst it knocks earlier with leaner AFR mixture... However, if you are using high octane fuel that allows you to run optimal ignition timing to get to MBT than a slightly leaner AFR can be used.

[@peterkroeker753]

Well I just got a $5000 education for 5 minutes of attention

[@mjodr]

And that's why HPA is the best.

[@mc1996]

LOL?

[@kathrynck]

Back to school with you! (that was 15 minutes) ;-)

[@i_am_tinny_man_2267]

@@kathrynck to be fair to Peter he did say "5 minutes of attention"

[@kathrynck]

@@i_am_tinny_man_2267 15 is three times 5 though. 300% markup, or 33% payoff per minute, whichever way you want to look at it. If you thought you were buying gas at $2 a gallon, and then it rang up as $6 a gallon... or only gave you 1/3 of a gallon of gas... :P (I am kidding, before anyone gets too excited and loses sleep plotting their argument).

[@XHikotheproX]

That's amazing I had no idea a NA engine would care that little. I like how you displayed torque only because it's what is really being measured for one, and is easier to see a difference all across the entire Rev range with torque rather than Power. The tune that I have for my car which is a NA V6 not dissimilar to the 350z engine has a target of .84 lambda at wot.

[@fredjones554]

Best afr demonstration ever! A comsummate professional. Hats off.

[@SouthernCrossMotors]

This video is an awesome find. I ran my ISF on a Dyno today and asked to show the AFR. The Lambda dipped to as low as 0.79 or so and I could see the dip in the horsepower curve in relation to the Lambda curve. My engine did make less power when below about 0.88. Will have to do some investigation as to why but thank you again for this video.

[@opexo]

if you could make the same 3 runs with temp. probes in the exhaust and show their data on the screen would be very helpful

[@realvanman1]

I'm impressed with how little difference such a wide variance in AF ratio made. As in virtually no difference! I would not have expected that. It would have been interesting to see a plot of EGT during each of those runs as well...

[@RandomlnternetGuy]

Agreed!

[@sleepr3263]

It surely rund into another limiter. My car has like 15 HP difference 0.95 to 0.85

[@caribbeangtr8077]

Such an important topic with massive impact on power and longevity of your expensive engine.

[@ronbown3836]

Maybe on the next demonstration you can demonstrate for the best lambda reading on methanol and see how wide of a tuning window there is with very little change in torque.

[@thhonyytone3478]

Awesome to share your tune on this part of a ECU...mostly on Dyno!!!!Thanks bro!!

[@getahanddown]

Damn Andre you're making 300+Nm at 2k! Am going to wire in an aftermarket ECU soon and will 100% sub to the courses

[@mateuszb.4011]

Explanation was 10/10 but I sometimes I had to rewind the video because I couldn't understand what you were talking about 😂. Apart from your accent the video deserves milion views 👌

[@hpa101]

Use the captions there Mateusz, it's what we do ourselves for tricky accents ;) Thanks for the compliment too, glad you enjoyed the video - Taz.

[@Toys4Life]

I love this type of video. I must say I though there would be more of a difference between the lambda's tested. Thank you for posting!!

[@shhhdontshout]

Why this channel still not 100k subs yet? Should be more than a mil already.

[@jdsimons6115]

Great demonstration. thing i take away from this basically is the AFR needs to be "correct" for the application. more lean or more rich within that spectrum makes little difference but outside of that either direction results in power loss etc.

[@Boost5.0stang]

Great video. I would love to take the course to learn how to tune but money is alway on a budget. These videos are much appreciated and love to see more.

[@turtlemotonation]

This channel is an amazing tool for beginners! Thank you!

[@shivnandankhatri137]

I really appreciate your lessons and especially engine tuning contents.

[@rixautomotive910]

Fantastic job on this video! When needed I will be sure to share with customers for validation ...absolutely no reason to push afr’s as it makes little to no difference in power.

[@SayWhaaaaaaaaaaaaaaaaaaaaaaat]

Next time also include EGT curious to see that too

[@Tysonrojas6969]

Been here since the start thanks for good info man 👍

[@rogerking7258]

In my experience A/F ratio is actually more important on light throttle where small variations can make a big difference to driveability. You have successfully busted the myth about A/F ratio being crucial for max power though, neatly demonstrating the BS you hear where the operator says he went up one jet size or increased the fuelling by 2% and suddenly found another ten horsepower. Have you ever tried this with a 2-valve engine? When I was involved in the business I generally found that it was necessary to run these very slightly richer, which I always put down to the less efficient combustion chamber; another effect of 2-valve combustion chambers being that exhaust valves were far harder to decoke due to the resultant much higher exhaust gas temperatures flowing over them (not because of the richer A/F ration which would have the opposite effect, but because of the less efficient combustion causing less of the heat to be turned into kinetic energy). Biggest danger to engines in my experience is not A/F ratio, but when the mapping guy has pointlessly pushed the ignition advance to the very limit and then the car gets a tank full of fuel that is very slightly lower octane than the test fuel. That didn't happen in the days of distributors simply because the timing was wobbling all over the place anyway and to think you could increase advance by half a degree meant you were laughably deluded. Am I giving away my age?

[@Alchemist37]

the clean shaven vs bearded switch threw me there for a second :) great video.

[@jaydenritchie1992]

depends on its fuel type, spark ignition if you lean on it, it will make power but run the risk of detonation (localized above the speed of sound events across the piston crown)

[@wiltse0]

It would be pretty cool to see the EGT and intake temps overlayed as well.

[@charliewolf7500]

Very well done tutorial. Excellent and relevant. I wonder if a lean burning 1.05 to 1.10 ratio, cooled with water injection (x6 individual port water injectors delivering water only) would yield any significant change in power or fuel efficiency? Thank you very much for sharing.

[@tiagobelo4965]

Absolute madman is giving us a class from inside a racecar, too bad regular classes aren't like this

[@stuckinmygarage6220]

The data do not lie. Good stuff. Thank you!

[@hpa101]

You're welcome!

[@gothicpagan.666]

That's some great dyno soft ware he has there. I always try to give the engine the absolute bare minimum fuel and ignition advance that it requires for maximum out put. If you are mapping in each gear timming advance will be a greater value and fuel needs to be leaner in first gear than it does in say eighth gear. One reason is to stretch out fuel consumption as far as possible the other is, it allows the engine to respond much cleaner at lower rpm. One interesting aspect would be to use an multi gas analyser and look at the H.C. reading, it's very telling

[@TanmayPanchal46]

Amazing stuff man. The demonstration is amazingly easy to understand, though not quite intuitive.

[@mugenrios2k]

Lamda+ignition timing( with lots of resolution) + knock sensor with lots of resulution+ EGTs again with lots of resolution and good response time on a load based dyno... MAN I MISS TUNING CARS

[@SinfidelityMusic]

I really enjoyed this. Thank u for the tips.

[@rickfinsta2951]

There is a NACA paper detailing this from a long, long time ago. Look up Technical Report 189 from the mid 1920s.

[@rustybeatty6567]

Multi-port fuel injection engines do a two stage process first stage is a 15.0:1 AFR second stage will add just enough fuel to give you a final AFR of 13.5:1 all the first stage does is to clean the intake valve or valves of carbon deposits through the intake port of the head then rest of fuel comes from the direct fuel injection part of the process.

[@az_3kgt714]

Trying to learn as much as I can. Gotta build that desperately needs a tune. Fueling up top seems to be good about 12.5-11.5:1 afr But down low on rpm and load the afrs are way too lean. Between 19:1 down to 15: at around 3-5k rpms. And most shops w ont touch it because its such an odd build.

[@joebrown9621]

Andre your the boss.. got to lift my hat to you 😎.. excellent content mann..

[@marcbelec6403]

whats ideal for boosted applications, can i target 0.8 lambda and call it safe as i dont rly have access to a proper dyno other than virtual dyno wich can be quite finicky

[@AlexM-tx2vr]

HPA, This is such a great video. I am probably the only one that is interested but it would be great to see a similar test on how efficiency (power/lamba) changes at partial throttle. I really want to know how lean I can run when I have high vacuum.

[@Aseutester]

Seconded!

[@rafilopes264]

Great dmonstration! Could you tell us which fuel quality was used to? Especiali was any Ethanol mixt in? Like at E10 gasoline❓

[@rickylah69]

i have a turbo car, my dyno run actually show the AFR start around 14.7:1 then full throttle to redline RPM, it starts to drop to around AFR 12.2:1. should i request a tune to have the AFR all the way flat when full throttle til redline?

[@khai4646]

Hi. I have a question. Rich afr can lead to knocking or not?

[@davidbrowne1588]

Hi this was very good to see, brilliant thanks, Dave

[@sergiogranato5562]

Absolutely great !!! Woud you consider next time aquiring EGT as well ? Then we could know how low Lambda has to go to provide sufficient cooling to the combustion chamber and how it compromises output.

[@LightningFast240]

around .92 from the o2 sensor your lookin in the high 1500s+ guesstimating from what ive seen in my logs

[@WorkinClassCanadian]

Thanks for doing this. I'm finally getting into tuning

[@Anthony-vr3um]

For boost I use 11.3-11.5 for n/a 12.5-12.8

[@PurpleHeartVR]

Tha'ts not a good comparison.. If a car is factory turbo, you don't need to junk it with fuel... If you game a 2L turbo from a cobalt ss, tuners who know the engine well always target 12.5-12.8 afr on stock turbo and stock engine and will make 330+ hp.. 380tq.. Then with a bigger turbo they will target low 12's .. It's a dI engine so no need to run rich... Even port factory turbo I would target low 12's... Now if it's N/A and high comp factory and you toss a turbo on top, then I would start to tap into the 11's at higher rpm's to keep it cool.

[@Anthony-vr3um]

@@PurpleHeartVR That's a no from me. The general concensus for a force induction vehicle is in the 11s and n/a mid to high 12s. Your 12.5-12.8 SPECIFICALLY on a cobalt is NOT a good comparison to anything. I own and tune a DI turbo car... also, there are a lot of direct injection cars out now and majority runs in the 11s with or added FI

[@scootbmx01]

@@Anthony-vr3um di's are much for efficient thats why they can be run leaner. It's not uncommon to see a modded, boosted di engine in the mid to high 12's on pump fuel and even e85.

[@ashteregg2133]

what would happen if you incteased timing by 2 degree when reducing lamda? from 0.9 to 0.85

[@Scootermagoo]

Timing creates whats known as negative work in the chamber, if you advance the timing to far the combustion process starts to soon and actually pushes the piston backwards. So adding more timing to a optimized system can work if the octane of the fuel is high enough to work with it but it's getting into negative results, making the piston change directions before the connecting rod has gone over center. Adding and subtracting fuel causes the ignition pulse to change where it happens, leaner is shorter sharper and faster, richer is like we modern people slower and a bit wasteful and takes longer to get to the point then this sentence. *yes I went there* So your engine and it's chamber design plug layout/placement etc etc etc.. is the basics, adding to much timing screws up the system so only use as much as you need or destroyed bearing uppers and melted pistons can and will be in your future. If you paid attention to the video this had nothing to do with spark timing and was giving basics on how afr works with your engine, asking for spark advance kinda missed the point of this. But since you asked this is your answer, it depends how close the timing is, how much is irrelevant to tuning except as a number and a place on a table and if it makes more power or not, not enough and combustion happens to late after the rod rotates around center and to much makes it happen before the rod is over center both lose power ones inefficient and one breaks parts. The total amount kinda depends.

[@scootbmx01]

@@Scootermagoo you mean you don't want the combustion happening as the piston is coming up? Haha

[@Scootermagoo]

@@scootbmx01 Well if you want your piston to actually stop fully before top dead center sure make it 75 degrees and see what happens. Most modern engines need 15-25 degrees of timing , you for example might need a 350 degrees of timing and a long roasting time, some of us are better off stewed at low temps, and others are good with a quick sear on a hot cylinder head. But as for timing mines off and I need to reset my watch. That should teach you to rewind your betters...

[@scootbmx01]

@@Scootermagoo you missed the joke.

[@Scootermagoo]

@@scootbmx01 So did you >;)

[@mattjonesturbo1]

Shaved off ten years bro, had me confused at first.

[@horacecunningham7832]

Didnt kno it was him at first

[@HentaiCheaters]

He prerecorded the 2nd part 10 years ago

[@jaileea2008]

Lol me too😂

[@danielcheng5070]

That's an amazing video! I am doing motorcycle tuning and found it very useful

[@leukefilmpjes9681]

Can u tell why -100 kpa is open throttle? Like more underpresure in manifold means wider open throttle right?

[@pswmetalmonkey]

The most under subscribed channel on KZbin..

[@GR8WHITEC5]

If my bike is tuned at 4,000 feet ASL, and I go down to 2,000 feet ASL, I understand it is "leaning out." So, if my AFR at 4,000 is say, 13.3, how would going down 2,000 feet effect my fuel? Is there a method of calculation per 1,000 feet? Such as, "As elevation goes up, fuel is adjusted by X% for every 1,000 feet change in elevation." So, to refine my tune at 2,000 asl, would I ADD or REMOVE fuel, and what % per 1,000 feet? I hope this makes sense. Is fuel compensated per 100 feet or 1,000 feet?

[@jesusherrerourtiaga4844]

Aprendo bastante con este canal,muchas gracias por crear contenido de tanta calidad.

[@googlesucks3520]

What an awesome demonstration thanks

[@hpa101]

Thanks mate! Hope it helps you out 😎 - Taz.

[@mattvanberkel7847]

Would be nice to see EGTs on all the runs 😁

[@oistein74]

Yes! Another point is with richer lambda you'll be able to run it for extended time and get same results. With leaner lambda it'll get so hot you'll loose power after a short time racing.

[@fabio77809]

thanks for the explanation and the video

[@TET2005]

Very clear and concise explanation! Subscribed! Looks like this NA car is not going to benefit from the dyno tune... probably the fuel consumption can be optimized by running leaner....

[@boosthit811]

Excellent demonstration.

[@hpa101]

Cheers mate, even I got caught up in this one =D - Taz.

[@chrisveeriah1524]

That was awsum guys, I really appreciate and thank you, best video lesson ever.

[@alvesthegreat]

How about very old diesels... I have an old one and all i can do is stiffen the waste gate spring... really dont feel that much boost but i dont know what else to do

[@randomsomeone1617]

I wish you would have also talked about the egt's as well. That is a key part of the puzzle, no?

[@jimbrown563]

The short answer is No. But. EGTs are affected more by Ignition and Cam timing events, especially ignition advance. Not having enough ignition timing will definitely run up the EGTs. EGTs can be more useful when you are running on the ragged edge of detonation, especially under boosted conditions. At some critical point, conditions in the combustion chamber, especially Exhaust Valve Head Temps, are going to cause the engine to go into run-away detonation........ The engine starts Detonating, then the knock sensors start pulling ignition advance, which makes the EGTs go even higher, meaning that the exhaust valves are now glowing cherry red, and you might be headed towards having a bad day. This is specifically why you must be very careful with pulling Ignition Advance under Boost, this can start making things very hot, very fast. As a side note........ When running an engine with Water Injection, you may find that the Water Injection makes the EGTs GO UP !!! But don't worry, the temps inside the combustion chamber are actually LOWER than before !!! The Water Injection also actively suppresses Detonation, much more effectively than Extra Fuel, and, water cleans out Carbon, extra Fuel CAUSES extra carbon deposits, which can cause hot spots, which promote Detonation. And, you can run stupid quantities of Water before starting to see a power loss. ( Running 50% Water to Fuel, (by weight), (under full load), is not unheard of ). A 50-50 mix of Water and Alcohol is even better, (instead of straight Water). Unfortunately, this last part only reinforces the fact that EGTs are of limited usefulness, unless you're doing research on a Dyno under controlled conditions. Per-Cylinder EGT probes can point out air flow, or fuel flow, discrepancies between cylinders, but that's not something that you can easily analyze by glancing at a gauge cluster while driving. An EGT gauge "could" warn you before your Turbo melts into a puddle. .

[@Nebbia_affaraccimiei]

Random Someone buy the course and I’m sure they talk about everything.

[@jimbrown563]

@@dogmoo Yeah, Water Injection is great stuff, with some really interesting, and unexpected, side effects, all good. rbracing-rsr.com/waterinjection.html#waterbtn1 has some of the best info on Water Injection that I've found, you may want to check it out, they are very serious racers, with a great sense of humor. .

[@marcstlaurent3719]

Excellent demonstration but I though max power was near 12.50 natural aspirated not stoichiometric of 1 lambda

[@rumrunrjones8546]

Great information. Well Done

[@gregoryshelton1358]

What is a safe afr at WOT?

[@lylegoodluck]

How does O2 sensor in pipe and tail pipe sniffer differ in tune?

[@hpa101]

The tail pipe O2 sensor might not be as accurate as oxygen can work its way back up the exhaust to the sensor (they are not that far away from the exit). That can't happen with it further up. Pre and post CAT is also a consideration. For general interest you can also have your sensors too facr the other way and have the readings skewed by exhaust back pressure. I'll link you to a members webinar lesson that touches on all these topic and more - Taz. www.hpacademy.com/previous-webinars/121-wideband-lambda-sensors-essential-knowledge/

[@roninmantis7584]

Nice explanation. Interesting when many tuners target an AFR of 13.0 or about 0.88 lamda, they are actual not achieving peak power. Which is closer to 0.92 lamda or 13.5 AFR. I realize in their mind this is a safety factor as fuel and conditions do differ. This is merely an observation. Curious if this is consistent across all gasoline engines.

[@carloscastillom.866]

Me gusto el video. lo mejor es usar el AFR que te la misma grafica pero usando el menos combustible posible.

[@tunedom6488]

what is besr afr for diesel to tune? for power and safety??

[@CreeperOnYourHouse]

How much does the graph change if you change the timing while changing AFR to take advantage of the rich conditions?

[@Spark972]

Reading the EGT at the same time would have demonstrate this easily. Also, sometimes you don't make more power but the oil get too hot very fast.

[@kalbi777]

Shouldn't timing be adjusted when afr is chsnged?

[@jaredlandetta5136]

Why would you set your Lambda target at .9 instead of 1.0. How does that change the performance or make it better?

[@hpa101]

Making it richer not only provides more fuel but also more cooling. Note though just as you can run too lean, you can also run too rich. There are points in the map where you would run richer and also leaner than 1.0 depending on load and RPM conditions (WOT is going to be very different to 0% throttle and low load for example) - Taz.

[@romanroman7327]

6:23 Hmm.. What about right ignition table comfortable for each flame speed, beacouse speed of burn changing for 30% in afr range?! This experiment is half or truth. We need table flame speed for each afr vs rpm vs air temerature, from this table we got ignition table for flame speed vs rpm

[@JohanGustavson]

Absolutly spot on video! Awesome!

[@dissidentjv5887]

Hello, this is very interesting but I'm French and I don't understand the all video, can just tell me for you what is the best lambda value for each regime 2000, 2500, 3000 etc ...

[@edward2a]

How about the EGT across the AFR range?

[@SkootaO]

awesome video. just a few questions: what does "eare" and "muicks" mean?

[@hpa101]

I'll never tell! But the captions will 😉 - Taz.

[@mdood9299]

How do you sit at a static engine rpm at WOT? I'm confused.

[@hpa101]

That is a feature our dyno allows, but you can also simulate it with left foot braking while road tuning. You also need a bit of common sense with that technique too ;) - Taz.

[@mdood9299]

@@hpa101 Thanks for the explanation Taz. I'm curious now, what's the limitations of that dyno for that mode of operation? Can you do this same method with a car laying down 1,000+ hp?

[@hpa101]

Yes, but you don't steady state tune high into the rev range so it's not really an issue, but even if you did you'd more likely overheat or damage your engine before a quality dyno. If for any reason you were working your dyno a little too hard there are sensors that will shut it down forcing you to let it cool off for a bit to save from any damage. As for steady state tuning, you only do it to a certain point and then you start doing sweeping runs higher and higher into the rev range so you're not running that car at high load and high RPM constantly for long periods of time while tuning - Taz.

[@mandoo414]

hey so basically if i get hp tuners that comes with the adapter (sorry can’t remember the word lol) I can access the air/gas data? I bought performance injectors and coils, (comes with copy and paste data so i’m guessing in good to go after it’s pasted into the tuner? lmk guys

[@hpa101]

If they support your vehicle you can purchase credits and use their interface tool (adapter) and software, yes. It won't just work on any vehicle - Taz. www.hptuners.com.au/vehicles/ www.hpacademy.com/technical-articles/reflash-tuning-solutions/

[@ras20V11]

Hello. Is it really for turbo engines, with boost of 2.5 bar? As I know, 0.86 afr, moves to high EGT…

[@drtalon1668]

Bitchin! Very rare to have theory and practice shown together in under 20 minutes. Excellent video, helped reinforce some of my own experiences and why I love tuning in lambda :)

[@texdevildog9174]

Awesome work. Can you show holding the AFR constant and changing timing?

[@hpa101]

Hey there Gary! It might pop up in a free lesson at some stage, but just in case note that content is on tap 24/7 via our course material ;) - Taz.

[@marcelocuadrado6955]

Very good test!!!

[@GTO2800]

Is it true that a leaner ratio doesnt make more power but increases throttle response?

[@TheMeanBean322]

Never heard of this but I'd like to know the answer as well

[@JasperSkallow]

that’s right. just grab the cheapest but not garbage carburettor motorcycle and become its master, up and down the highway with each change

[@PurpleHeartVR]

No, the faster you get that air into the combustion chamber, the better throttle response... And well, other things.

[@nismofreak33]

in my experience no. if you are lean and your acceleration enrichment is lean the engine will die for half a second with relatively decent throttle changes.

[@kusomuchogusto5742]

Does overlap effect the a/r value on the wide band sensor?

[@vincentrobinette1507]

Best to miss rich. that ensures that you're oxidizing fuel, not parts!(specifically, the exhaust valves and seats) especially in high-performance race engines.

[@dedekfik9804]

so. 0.95 is the best lambda for power? 13 afr?how lambda for the healthier engine balance power?

[@terjehansen0101]

There is a spectrum somewhere in between approx. 13.0 -15.0 that can be very bad due to high cylinder temperatures and potential knocking. This becomes apparent at high engine load (lots of throttle). There is a diagram somewhere about EGT (Exhaust Gas Temp.) and Cyl. Temp. So for max power i'd go for 12 - 12.5 and for economy around 15.5. Some expert drag racers have lots oil cooling, air/water cooling and cooler spark plugs to mitigate the temp. problem and can get closer to the "danger zone" and get max power.

[@TheSilviu8x]

Gee, you saved me countless sleepless nights!! I was getting mad, by not being able to tune my bike, after getting a 700 💶 street legal full exhaust! The damn thing fries the Powercomander solution... Now, I'll just focus on the pumping side of things! I'll buy you a truck of 🍻🍻, if i could..

[@krusher74]

in old skool terms .95 to 1 is only 14 to 14.7 to one fuel air ratio, that pretty hard to target accurately with a carb/s, its not that wide a range when you don't have a computer the control it

[@朱建宇-e7k]

Will the situation of turbocharge engine be the same as NA engine?

[@yoyyoy4789]

during idle better 14.7 or 1 lambda?

[@RB26N]

perfect , amazing work.

[@hpa101]

Thank you! Cheers!

[@jstdrv]

So on a street car, with 0.95, you can save fuel and still have full power. On a forced induction or high comp engine i agree 0.86 to 0.90 is probably safer!

[@hpa101]

Beauty too is that difference parts of the map can have different targets where applicable. Cruise vs wide open throttle for example. This is something that a lot of people can't wrap their head around when it's stated that a performance tune can give you more power AND more economy vs a stock tune in many cases 😎 - Taz.

[@jstdrv]

@@hpa101 i did this on my old TVR chimaera that i turbocharged. I had a ms3 ECU in it and did logging on the road and set wot with full boost to about 12,5 afr and cruise to about 13,5. The rover 4.6 didn't feel happy at 14.7 🙂

[@intergrale4x4]

Great Video and info !! Does a turbo charged engine behave the same ??

[@Mitutumuch]

So, technically, I can do this on the street? I could change it from a basetune to a leaner tune trial and error based on 0-60 time?

[@Mitutumuch]

or the 0-40 times

[@1hates2love5]

This may be a dumb question but how come you measure torque at a continuous 2000 rpm to find out max torque with afr as a variant and with power you didn’t keep rpm constant but redlined it??

[@timm.6391]

Around 2k is an area of higher load on most cars and torque typically comes in lower rpm than HP. It's a good way to way to get a AFR roughed in before you start hammering the car and having a boom situation.

[@chrisssinstockholm]

I have read in a book from aprox. 1940-1950 thax max power is produced @ 0,86

[@hpa101]

That book is incorrect. This lesson shows why 😉