SR20 individual cylinder AFR tuning..

[600supersport]

Just curious if anyone that has actual experience with lambda readings per each cylinder on the SR20 would care to share any info. Ricer math says cylinder #3 could use maybe 3-7% of extra fuel and #2 & #4 a little less, but still extra. Obviously every setup will be different and keeping overall block/head/trans temps under control is important, but EGT sensors are slow to react and reading spark plugs isn't as precisely quantifiable as AFR...maybe you've done a lot of testing with individual cylinder EGTs on the SR and I certainly wouldn't turn down your findings either...just curious

[fatduece]

Mate, you're out of luck. Ain't nobody here can afford such lavish tunes and even if they could, they're too busy trying to achieve credit card fitment.

[600supersport]

I'm sure there's some decently funded teams out there doing it...too bad they don't bother to share with us mere earthlings. Some day I'll bite the bullet on another manifold and the AEM 4-channel setup and contribute something relatively newish here.

[fatduece]

Don't forget to report back!

[Croustibat]

"Ricer math says cylinder #3 could use maybe 3-7% of extra fuel and #2 & #4 a little less, but still extra. "

Why ?

[600supersport]

I don't have personal experience with individual cylinder EGTs (only ran one on #2 personally on my last setup) on the SR and haven't seen a whole bunch of variation in my own spark plugs, but others have observed it running warmer in the middle of the engine with bias toward the warm transmission too, fuel rail pressure drop-off at the rear and I'm just guessing intake manifold design may give a little more air to #3 as well so that's my idea of ricer math in this scenario. I'm just curious if anyone has done some testing with the 4-channel eugo setups yet on this platform.

[ultimateirving]

Do it do it. No cash to spend on car parts right now

[HybridAndy]

If you imaging a log intake manifold

_________
TB ==
|| || || ||
cylinders

You'd expect cylinders closest to the throttle body to get the least air and the cylinders at the end to get the most. Image spraying a water hose into that system, where would most of the water flow out? That's not a completely fair comparison but demonstrates the point. In normal operating conditions, it's a small difference and if your tune is sufficient to keep your "combined cylinder" AFR (IE post turbo O2 sensor) where you need and without detonation, there's no reason to tune individual cylinders.

The only people who would have this needs is if they run in a class where your forced to run certain parts or a restrictor plate and you need to extract the maximum possible from what you have (think a spec series where 2-3hp could make a difference if everyone has the same setup). You'll get much better gains and better return on investment somewhere else (more efficient turbo for your power level, cams, intake manifold ...).

I'd be curious if my hypothesis is correct (water in manifold thing) with some kind of scientific testing but with my experience working on Honda's, when a headgasket or piston failed, it's was usually the next to last or last cylinder from the TB. My assuming was those cylinder were running the leanest and also furthest from the incoming cooled water from the radiator (and a bad tune).

[600supersport]

That all definitely makes sense to me and I'd prioritize the money spent elsewhere to obviously since I haven't done it yet, but as you pointed out with the furthest cylinder results, one thing about seeing the average cylinder lambda being where you want it is that one or two cylinders may be leaner than you want, but the other 2 offset it into the average. It's very easy to account for individual cylinders fuel & timing in the tuning software, but real world lambda data on this platform would shed some more insight as a starting point window on other setups beyond what others have observed with EGTs.

[Kingtal0n]

The only people who would have this needs is if they run in a class where your forced to run certain parts or a restrictor plate and you need to extract the maximum possible from what you have (think a spec series where 2-3hp could make a difference if everyone has the same setup). You'll get much better gains and better return on investment somewhere else (more efficient turbo for your power level, cams, intake manifold ...).


yes!


My assuming was those cylinder were running the leanest and also furthest from the incoming cooled water from the radiator (and a bad tune).

sometimes a motor is setup to deliver coolant to the back of the head first, making it less prone to detonation in #4 even though that cyl may run leaner. In other words, Factors you do not see sometimes contribute or reverse the situation from what you would expect.

Also, acoustic tuning of intake runner length often has much more of an effect 5-10% of air mass ( the manufacturer knows that for a given range VE will be higher than it should be ) than a discrepancy in the design ( i.e. an extra 3% at the rear - you never see an OEM sr20det runner smaller or differently shaped in the rear, despite all the manufacturers testing/development which would show any "problem area")


Once you step up to "greddy style" intake manifolds the loss of traditional long-runner acoustic tuning leads to different designs, i.e. the funnel shape as the plenum approaches #4 with its really short runner design must have been what they found to be most effective (i.e. there would be some kind of testing/development before you buy a part like that, otherwise you should not buy it or trust it )

[600supersport]

If we keep talking about this long enough, someone will chime in with actual experience lol

[LoSt180]

This sounds similar to a problem with the G35/350Z where the first two cylinders got less air due to the shape of the intake manifold and ran rich. Most fixes involved changes to the manifold to balance out and provide better airflow.

Interesting stuff.

[Croustibat]

If we keep talking about this long enough, someone will chime in with actual experience lol

We are on zilvia, the thread is about expensive and highly advanced tuning.

People who do that won't share the info ( first, because they don't post here, second because they don't want to give precious information for free).

[brndck]

I thought Bill Washburn from DentSport ran a setup for individual cylinder tuning. He's into some pretty advanced shit.

[600supersport]

I know most don't bother sharing info like this here, but it's not THAT expensive, not THAT advanced and not the secret key to a professional tune...

[brndck]

there was an article a while ago, where iirc bisimoto tuned a turbo s2000 with aem individual wideband sensors, and they picked up like 40whp just by balancing out each cylinder; leaning out the overly rich ones and richening up the lean one(s). I'd say that's worth the cost right there.

[600supersport]

Cool, I'll have to look that one up, though I doubt most setups will gain that much power if any at all, just better overall calibration since we're making a lot more than stock figures.

[brndck]

this is not the article I was thinking of, but similar. they picked up 17hp/16ftlb on an NA s2000
http://www.superstreetonline.com/how-to/engine/impp-1205-aem-4-channel-wideband-uego-series-2-ems/

[brndck]

this is not the article I was thinking of, but similar. they picked up 17hp/16ftlb on an NA s2000
http://www.superstreetonline.com/how-to/engine/impp-1205-aem-4-channel-wideband-uego-series-2-ems/

[Croustibat]

I know most don't bother sharing info like this here, but it's not THAT expensive, not THAT advanced and not the secret key to a professional tune...

4 wide afr sensors, 4 EGT sensors, harness, an exhaust header custom made for the sensors, ECU capable of commanding injectors separately, software to datalog all that, countless hours for tuning, YES that is way more expensive than an AFR sensor in the elbow and a nistune. I'd say that setup is easily worth 4000$ more.

On a similar budget, you'd either get a perfectly tuned T28 based engine with like 300WHP, or you'd get a twinscroll EFR turbo with a standard custom tune and 450WHP.
Sure, it might be less efficient. But it will have both less lag and more HP, even if a 4 AFR/EGT could net more power from the same setup.

I know which one i'd get.

It is not much more complicated to tune, sure, but it really is way more expensive and longer to do, and unless you NEED these last HPs in a competitive class, it is absolutely useless. My tuner is getting around 700HP out of a ca18det with e85, and he is doing that with a simple nistune, 1 AFR and 1 EGT sensor (he just blew his z32 gearbox and went Z33)


BTW that "S2000 example" is worth crap, the HP gain has nothing to do with balancing each cylinder, it has to do with going from a mail order tune to a custom made tune ...

[600supersport]

Croustibat, this isn't a discussion about why and who should use this lol especially if your tuning setup can't already handle analog inputs (or CAN) for datalogging like this, but I guess it's just another reason to use Nismotronic if nistune can't, but many others can too.

You absolutely do not need EGT probes to go with this. All of the 4 channel hardware is ~$1k plus 4 bungs welded into an existing manifold (if you can't weld) so maybe $300 more and an extra $100 hour on the dyno (not a 20 hours) so an absolute max of $2k because you already have a capable tuning setup. I'd get it done for about $1,300-1,500 max...people spend more on head work and wheels all the time lol.

Again this isn't to discuss who and why, I'm just curious if someone has actual usable input to share.

[HybridAndy]

The other issue is, anyone who's done this testing, probably isn't running the stock intake manifold or using an unmodified head so the values won't have much meaning for your package.

Honestly, this is the kind of tuning someone like Nissan would do when it's invested hundreds of thousands of dollars into a world challenge or touring car program and needs that extra 2-3hp and 1-2 mph on the straight so they can shove it in Honda or Volvo's face. Your probably talking about going from 88% to 89% duty cycle on individual injectors and making very little difference. They would also probably share this information with other factory backed teams running the same engine but wouldn't ever release it publicly.

That said, there are people who are more interested in efficiency than ultimate output and it's possible someone has done this testing. I have a Greddy EGT sensor tapped into one of the head shield bungs on my #2 cylinder but I just like having it to monitor the overall health of the engine (figured it would help if I ever had a failing fuel pump or something to warn me of climbing EGTs before the engine pops). I've worked on a few equal length Subaru manifolds before that have existing provisions for individual EGT sensors but I've never seen someone with them hooked up.

[Kingtal0n]

You have to be joking with these figures.

If I can make 500-600bhp with an $800 OEM longblock on an $140 single wideband sensor safely,

and others are producing 2000+WHP with the same $140 single wideband sensor,

I don't see any demand for such a product/project and infer that anyone using such a complicated mess is either rich and bored or just foolish, disgusting thread is disgusting, flow match a set of high quality injectors and call it a day

[fatduece]

I think the advantage of these tunes are in the added reliability. It's probably the reason why "built and tuned" motors don't last as long as OEM. The power gains are just a bonus.

[600supersport]

I'm glad AEM does "see any demand for such a product". The trick is compensating for the backpressure present pre-turbo or else you'd be able to just route 4 independent O2 sensors into your analog inputs and log that and tune according quite easily. It is nowhere near a necessity to making power and even reliably as I have and still haven't invested in one yet beyond my single O2 and EGT sensors, but I'd say it is the best way to maximize your true lambda since there's 4 combustion chambers, not one. Every mod that everyone does to every car obviously affects someone else's differently, but findings on my engine are something I'll take with a grain of salt...again, not here for the why and who lol but if you guys still wanna theorize, at least it hasn't been beaten to death a million times yet...

[RedtopTech]

Weld an o2 bung to each runner. Wear a leather glove and swap your sensor between runs. This is a cheap and easy way to ensure that your money and hardwork doesnt "go up in smoke" by tuning to the leanest cylinder.

[600supersport]

I'd be interested in the steady state too, but give it a rip and I'll read the shit out of your findings

[Croustibat]

using 4 AFR probes but no EGT is so stupid ... i can't ... even ...

Anyway, i got my ass in an S13 yesterday. Has only 1 AFR/EGT. 9000rpm, 2.2bar boost ... with the boost controller turned off. Can do up to 2.8bar boost. That thing hauls, you have no idea.

Guess what ? He went the "i'd rather get a bigger turbo than a fancy tuning system". He has been drag racing this engine for years now, he has blown turbos, transmissions, but the engine block ? Nope. Still there, no piston, rings, or rod change. Nothing.

So yes, this IS a discussion about when you should spent money and time on an overkill tuning setup, and when it is not worth the trouble, because you may have unlimited funds but most of us have to make a choice.

And frankly, you should not even talk about tuning an engine, let alone individual cylinder tuning, when you have no idea why an EGT probe is needed.

[600supersport]

You're still missing the point, but keep trying

[HybridAndy]

Just to throw a little fuel on the fire, I saw the following article on MotoIQ regarding their MkIV Supra with the following line.

The car ran great for several years until multiple fifth-gear passes one day caused cylinder #1 to eventually melt down at the piston. The culprit was determined to be not insufficient methanol reaching cylinder #1, due to the sudden bend of the factory lower intake runner. Therefore, the ignition timing was too high in that cylinder, given the available octane. The rest of the cylinders, which were getting methanol, were perfect, but they also had a much straighter shot through the factory intake runners into the intake valves.

http://www.motoiq.com/MagazineArticles/ID/4159/Project-Toyota-Supra-Mark-IV-Part-14--Precision-Turbos-GEN2-PT6870-CEA-turbo.aspx

Just thought it was interesting.

[brndck]

Just to throw a little fuel on the fire, I saw the following article on MotoIQ regarding their MkIV Supra with the following line.



http://www.motoiq.com/MagazineArticles/ID/4159/Project-Toyota-Supra-Mark-IV-Part-14--Precision-Turbos-GEN2-PT6870-CEA-turbo.aspx

Just thought it was interesting.

determined to be NOT insufficient.....

so it WAS getting sufficient methanol? or it was NOT getting sufficient methanol?

[RalliartRsX]

EDIT to the end

[derass]

Just curious, how could that have been detected? What sort of (individual cylinder) AFR or EGT behavior would have indicated the problem?

I just checked my Haltech software and indeed there are individual cylinder trims for both fuel and ignition. So that failure could have likely been prevented by compensating for the intake manifold flow characteristics with those corrections.

However, it begs the question: at what point does decreasing the output of a single cylinder cause enough of an imbalance of forces at the crankshaft that a new problem is created?

[600supersport]

Maintaining proper combustion chamber pressures & temperatures is paramount. Being leaner doesn't always mean that you have a higher power output, but having the correct amount of fuel for the oxygen content along with the right timing advance will give the highest power output.

[Arrowking]

I don't understand why this is being shot down. If anything it just adds to the knowledge base of the forum.

I, for one, am very interested in individual cylinder tuning (I'm a nerd like that) and would like to see it on a SR20 setup if only to see the data.

[Croustibat]

I don't understand why this is being shot down.
[...]


While it sounds cool, there are just better ways to spend your money. Unless you compete in a class that does not let you spend your money better, a 2000$+ turbo upgrade will always net more power than individual cylinder tuning.

You will never get that kind of information on zilvia, because... well, first, this is zilvia we are talking about. People here care about how low their 300$ coilovers can go and how their counterfeit bodykits and wheels look like.

Second, again, this is advanced stuff. The kind you don't give for free, but use as a consulting selling point.

@derass > individual EGT would have shown the supra problem. I don't know about AFR, since it was more of a heat problem due to not enough meth to cool, and i don't know how AFR sensors react to meth.

Individual tuning allows for the "perfect timing and AFR" on each cylinder. The problem is to keep this going after each fuel tank. I don't want to remap every time i fill it up, or when it gets hot, so i just add some fuel and remove some timing; this way the engine has safety margin.

This is exactly the same thing tuners do with mail order tunes vs dyno made tunes.

[600supersport]

Stellar additions every time crousti posts, much appreciated insight lol. Imagine if this was a one to two post thread where I wrote the original paragraph, maybe no one replies, but if they did it was with actual experience and insight then other people read and move on. You say poor Toby...I say poor us.

[Arrowking]

While it sounds cool, there are just better ways to spend your money. Unless you compete in a class that does not let you spend your money better, a 2000$+ turbo upgrade will always net more power than individual cylinder tuning.

You will never get that kind of information on zilvia, because... well, first, this is zilvia we are talking about. People here care about how low their 300$ coilovers can go and how their counterfeit bodykits and wheels look like.

Second, again, this is advanced stuff. The kind you don't give for free, but use as a consulting selling point.

@derass > individual EGT would have shown the supra problem. I don't know about AFR, since it was more of a heat problem due to not enough meth to cool, and i don't know how AFR sensors react to meth.

Individual tuning allows for the "perfect timing and AFR" on each cylinder. The problem is to keep this going after each fuel tank. I don't want to remap every time i fill it up, or when it gets hot, so i just add some fuel and remove some timing; this way the engine has safety margin.

This is exactly the same thing tuners do with mail order tunes vs dyno made tunes.

Sure there are better ways to spend your money but OP didn't ask about the best dollar for horsepower modifications.

I very much agree that on this forum it's more about credit card fitment (no matter how much I'm not a fan of it), but it'd be nice to have some actual interesting knowledge on here.

It may be advanced but once again, why not? Usually this definitely is a service you pay for but if someone wants to chime in with some tidbits of information that's not a bad thing.

[RalliartRsX]

One thing to keep in mind when dealing with EGT and why, in my eyes, they are a supplement to AFR tuning and NOT a requirement as Crousti is seemingly harping on.

1) Rich and lean burn conditions can both produce stratospheric temps. Lean conditions are obvious why. however, Rich conditions lead to continued burn AFTER the exhaust valves are open due to the mixture being fuel rich......So unless you know the actual A/F ratio this is occurring at, you are essentially tuning blind if just basing running conditions solely off the EGT readings.
2) With modern day knock sensors, using the EGT to tune timing is seemingly archaic and one dimensional. Knock sensors are much more accurate in enabling the tuner to take it right up to the edge and account for a safety factor
3) Proper EGT's are dynamic from engine to engine (this is also within the same engine family).

And the best part about Crousti's posts?? He is complaining about Zilvia not having knowledge........ all the while adding nothing, zip, zilch to the discussion.........and accomplishing the same thing he is bitching about lol! Ohhhhh the irony :D

[KAT-PWR]

Sure there are better ways to spend your money but OP didn't ask about the best dollar for horsepower modifications.

I very much agree that on this forum it's more about credit card fitment (no matter how much I'm not a fan of it), but it'd be nice to have some actual interesting knowledge on here.

It may be advanced but once again, why not? Usually this definitely is a service you pay for but if someone wants to chime in with some tidbits of information that's not a bad thing.

If you don't find quality information on this site you have not looked. There are plenty of threads that contain good information.

[Arrowking]

If you don't find quality information on this site you have not looked. There are plenty of threads that contain good information.

I didn't say that there wasn't any quality information just that it seems to be more about wheel fitment and cosmetics. This is just comparing topic for topic and what seems to be valued. Of course, there is great information here on all sorts of topics (wheel fitment, engine output, engine reliability, etc.).

[Croustibat]

Sure there are better ways to spend your money but OP didn't ask about the best dollar for horsepower modifications.

I very much agree that on this forum it's more about credit card fitment (no matter how much I'm not a fan of it), but it'd be nice to have some actual interesting knowledge on here.

It may be advanced but once again, why not? Usually this definitely is a service you pay for but if someone wants to chime in with some tidbits of information that's not a bad thing.

OP asked for specific information, for free, on a forum dedicated to credit card fitment. Wrong place to ask, and this is just my opinion, no one knowing will tell because specific knowledge has a price.

Have you ever seen a tuner - that still is in business - telling the details of what made his business attractive ? The kind of details it took months / years to get right ?
I never have, and this is the same reason the OP won't get any info about that here.

One thing to keep in mind when dealing with EGT and why, in my eyes, they are a supplement to AFR tuning and NOT a requirement as Crousti is seemingly harping on.

1) Rich and lean burn conditions can both produce stratospheric temps. Lean conditions are obvious why. however, Rich conditions lead to continued burn AFTER the exhaust valves are open due to the mixture being fuel rich......So unless you know the actual A/F ratio this is occurring at, you are essentially tuning blind if just basing running conditions solely off the EGT readings.
2) With modern day knock sensors, using the EGT to tune timing is seemingly archaic and one dimensional. Knock sensors are much more accurate in enabling the tuner to take it right up to the edge and account for a safety factor
3) Proper EGT's are dynamic from engine to engine (this is also within the same engine family).

And the best part about Crousti's posts?? He is complaining about Zilvia not having knowledge........ all the while adding nothing, zip, zilch to the discussion.........and accomplishing the same thing he is bitching about lol! Ohhhhh the irony :D

I said AFR and EGT were mandatory, not that you could do without AFR if you get an EGT sensor, so while i agree on your 1) point, it kind of falls flat.

Point 2) is true only with low octane fuel. Knock sensor is useless when tuning with high octane fuel like e85, because you don't get knock. You can go past the best ignition timing and put huge stress on the rods and pistons and still have a 0 knock count, while even non alcohol based high octane pump fuel will get knock way before getting the best timing. I don't tune on pump gas except e85.

point 3) well, yes, agree. Can't really see your point there.

I am not complaining at all about zilvia not having knowledge, but stating the obvious since some the OP and some others don't get it.

There is ONE thread with actual info that makes car go faster in this whole forum, and it is the suspension thread. Even then, it is turning sour too.
Also, if you want to slam your missile drift car, compare fake wheels, fitment of body kit copies, or ask about any kind of useless junk and counterfeit item you can get for an S/R chassis or laugh at the guys who do that, zilvia is the right place to go.

If anyone want serious data about anything else, zilvia is the wrong place.

[Kingtal0n]

Plenty of 600bhp small blocks ran in 1967 just fine without computer controls

You read the plugs, tune for vacuum, use common sense. A/F gauges and EGT sensors are just icing on the cake if you know what you are doing.

[RalliartRsX]

Crousti

1) Fair
2) Correct. My synopsis is on non E85 fuel
3) ....
4) The irony behind your complaint against Zilvia is perplexing.......... Just take the time and get off your soap box and post legitimate info is a good recommendation.........or go "lay some pipe (get laid)" and stop being so frumpy ;)

[Arrowking]

OP asked for specific information, for free, on a forum dedicated to credit card fitment. Wrong place to ask, and this is just my opinion, no one knowing will tell because specific knowledge has a price.

Have you ever seen a tuner - that still is in business - telling the details of what made his business attractive ? The kind of details it took months / years to get right ?
I never have, and this is the same reason the OP won't get any info about that here.


I see your point but it's not like asking on here is totally useless. On other forums and comment sections, there have been numerous times where an actual powertrain engineer responds with great info that is perhaps even better than what you would get from a tuner.

Also if you were to go to another forum like Nissan Road Racing you'd probably get better responses but I'm sure some of those posters post over here. It's not like you can only be apart of one forum.

But I do see your point, I just think it at least is worth posting.

[Frank_Jaeger]

Have you ever seen a tuner - that still is in business - telling the details of what made his business attractive ? The kind of details it took months / years to get right ?
I never have, and this is the same reason the OP won't get any info about that here.
This is the internet, people share things here. Sometimes incidentally valuable things.

Maybe we should go back to TBI because it works and people used to do it without any issues.

Anyway I've always been interested in per cylinder lambda readings but mostly for safety / diagnostics. I don't see why individual cylinder tuning would be prohibitively complicated compared to average tuning. A little more work for sure, but in principle it's the same concept, just with higher resolution and one more step in the process.

With the state of modern embedded hardware there's absolutely no reason a standalone shouldn't be able to swiftly handle these "advanced" features. If tuners charge a premium beyond the scope of the work / extra time it's not because it's somehow harder to do, but because it's a setup in less demand and 'exotic.'

[600supersport]

The best part of this discussion is that crousti actually has nothing better to do with his time.

[claaasssiiiccc21]

Hate to bump an old thread but this has the potential to have some good information. Croustibat is dead on the money. EGT is vital to each cylinder. Has anyone on here ran a high HP (800+) SR20VE-T with Mazworx IM happened to check EGT per cylinder? Seems like a must for any high HP 4 cylinder looking to extract more power and add some safety.

[600supersport]

People have been logging individual cylinder EGTs forever, but it doesn't tell the whole story. Lambda and EGT are both vital, but the lambda is more important and this thread isn't about discussing theory of individual lambda or egt, but just seeing if someone that has actually used the AEM system for example would care to share their actual experience even though every setup will vary.


SR20VET • RS5R30A • S14

[unndat]

If we keep talking about this long enough, someone will chime in with actual experience lol http://goo.gl/jexrVP