Dyno day & tuning

[BadazzSr20]

Hey guys,

So I have a dyno day for me set up for this Saturday. I been tuning my car on the street and its comming along very well. So I set up a dyno day for myself to see how good of a tune I have done. Well I have a question about the dyno. I have been to a lot of dyno runs I have done a few pulls before but I never tuned on it before. I know the basics of the dyno the only question I really have is that how do I know if a rpm is to learn or to rich by looking at the dyno graph?

I have searched by I haven't found any help with this I guess tunners like to keep shit a serect lol. I think I have an idea how it works but I would like to know forsure rather then guessing.

Thank you guys

[ultimateirving]

The afr's should be close to 12.0 if your running 91.. And when you get the dyno printout, it willtell you the afr all throughout the rpm range, Its all about reading the graphs. Also if possible, some dyno tuners can hook up a gauge to one of you boost lines to get a boost graph too.. So you can see all three together.

[Tom N]

The dyno read out should show AFR by rpm. You can't tell just by looking at hp/tq numbers.
Do you have a WB hooked up in the car?

See line at bottom of dyno graph

[BadazzSr20]

The afr's should be close to 12.0 if your running 91.. And when you get the dyno printout, it willtell you the afr all throughout the rpm range, Its all about reading the graphs. Also if possible, some dyno tuners can hook up a gauge to one of you boost lines to get a boost graph too.. So you can see all three together.

Well ill be running 93 and I'm aiming for 400whp so ill be looking more at 11.5 and less.

The dyno read out should show AFR by rpm. You can't tell just by looking at hp/tq numbers.
Do you have a WB hooked up in the car?

See line at bottom of dyno graph
I have a wide band installed in my car yes. But I thought there was a way to see the A/F on the graph itself so I can see like for exsample that I'm running lean on 4200rpms and I can just fix it.

If I have to watch my own wideband to get the reading of a/f then what's the point of a dyno just for numbers?

[Tom N]

Did you look at the dyno graph I posted?

[BadazzSr20]

Did you look at the dyno graph I posted?

Yea how do I get that when I'm at the dyno? Do u have to install something for it to read my air fuel?

[Gar9854]

Why does everyone assume power is made by AFR's? Yes it is crucial to keep an eye on it but power is made through timing.

[BadazzSr20]

Why does everyone assume power is made by AFR's? Yes it is crucial to keep an eye on it but power is made through timing.

Yes I understand that but with a afc the timing is added on its own. So the cleaner ur a/f mix is the the more the timing will be ajusted the more power u make.

[Tom N]

Yea how do I get that when I'm at the dyno? Do u have to install something for it to read my air fuel?


The stick a WB sensor in your tail pipe that's read by the dyno software. The dyno operator will know what to do. If they don't move on.

[Tom N]

Why does everyone assume power is made by AFR's? Yes it is crucial to keep an eye on it but power is made through timing.


It's made thru boost, a/f and timing.
All three are equally important and there's no magical number that is best for every set up even when set ups are very similar.

[Tom N]

Yes I understand that but with a afc the timing is added on its own. So the cleaner ur a/f mix is the the more the timing will be ajusted the more power u make.

Not necessarily. A AFC is a terrible tuning tool in today's market.

Just because you are leaning the a/f out doesn't mean more timing there will make more power and vice versa.

[BadazzSr20]

The stick a WB sensor in your tail pipe that's read by the dyno software. The dyno operator will know what to do. If they don't move on.

Right on i understand now thank you.

[jr_ss]

Yes I understand that but with a afc the timing is added on its own. So the cleaner ur a/f mix is the the more the timing will be ajusted the more power u make.

Wait wut? You're tuning with an SAFC? You've got to be kidding right? Throw that shit in the trash and get real tuning software. You aren't tuning, you're manipulating a signal.

[ultimateirving]

Wait wut? You're tuning with an SAFC? You've got to be kidding right? Throw that shit in the trash and get real tuning software. You aren't tuning, you're manipulating a signal.

You never told us you were using an SAFC!
Please dont blow your engine they are not reliable tuning tools and they dont let you manipulate the timing which is where the danger lies!

[Tom N]

You never told us you were using an SAFC!
Please dont blow your engine they are not reliable tuning tools and they dont change timing which is where the danger lies!



Actually they do change timing. Problem is they change it in a way you don't have complete control of. A AFC alters the air flow signal to the Ecu which in turn alters what fuel and timing cell the Ecu uses. It's a terrible way to tune.

[BadazzSr20]

The stick a WB sensor in your tail pipe that's read by the dyno software. The dyno operator will know what to do. If they don't move on.

I think u guys are 100% right about the safc if I had a sr or a ka then yea it might blow. But that's not the case here I seen with my own eyes and on just about every supra forum there is that there all
Making 750whp with a Ecu and a afc running as a daily so I will do what I have been doing to the pass few years.

I'm not going to reply or answer to any other negative remarks. I understand and I do agree with you all and the safc. But I'm not here to debate about the afc and how everyone hates them I get lets move thanks.

P.S
So far I have been DD 500whp with this set up. But thanks for your concern ill be fine I'm sure.

[Tom N]

Lots of ways to do things half assed. And the motor you have whether it be a SR, KA, 4g63, 2jz doesn't matter at all. Your car will never run as good as it could using a AFC as your tuning device. But to each their own.

[jr_ss]

I think u guys are 100% right about the safc if I had a sr or a ka then yea it might blow. But that's not the case here I seen with my own eyes and on just about every supra forum there is that there all
Making 750whp with a Ecu and a afc running as a daily so I will do what I have been doing to the pass few years.

I'm not going to reply or answer to any other negative remarks. I understand and I do agree with you all and the safc. But I'm not here to debate about the afc and how everyone hates them I get lets move thanks.

P.S
So far I have been DD 500whp with this set up. But thanks for your concern ill be fine I'm sure.

The only reason you're getting "away" with it is because you're using a 2j. Even then it is not an optimized way to control your engine. If I had that much invested in a motor/setup, I sure as hell wouldn't be using the cheapest "tuning" option available.

Like Tom said, to each their own... Goodluck.

[BadazzSr20]

Like I said I'm not here to have a battle about safc this is my last response about this. I been useing a standalone in the pass 10cars I have owned. People on here that know will tell u that I don't "cheap" on anything. I will too have to go standalone once I hit my 750whp goal. This is what I do I push shit to the limit I don't care if it blows up ill buy another and another and another I'm not asking anyone on here for money to buy my
Motors I buy them my self.

So if I want to blow my motor or anyone else on this forum for that matter that wants to blow there motor it should matter to any of u what people do with there stuff. Worrie about ur own cars and not others. If I wanted advice about " should I use a safc or a standalone I would have opened a Thread asking this question.

I told u all more then once that I agree that the safc are a peace if shit and if I had any other motor in my car it would have a standalone like the last 10 did. Again I thank you for your concer but ill be fine.

Thank you for everyone that helped me with my questions and I got it from here. If the time ever comes that I need advice about safc or standalone ill make sure I hit u guys up.

I know this might sound rude when ur reading it and I'm sorry for my rudeness but the truth is I didn't ask your advice about my safc and a standalone. I asked u all to move on and u still have to put ur 2cent in witch is fine but again for the 4th time cause maybe u all did hear me the last 3 times. Ill be fine and if not ill just drop a new one in thanks again guys for all the help.

[Croustibat]

blah blah blah i know it all and you all suck.

You still have an easy alternative between SAFC and standalone, it is called nistune. No rewiring or anything, just a socket to add in the ECU, and you get complete control. Not as good as a standalone, yet a billion times better than an SAFC. And it does not cost much more than an SAFC + a dyno run.

Although i have a hard time believing you can tune anything considering you believe timing is adjusted by magic when using an SAFC and never went to a dyno.

That being said, your dyno session is useless as you did not do a base dyno first. Dynos have to be used relatively, not absolutely. You dont do a dyno run if you want to use it properly, you do a base run, then multiple tuning runs with various braking force, then a final run and compare to your base run.

Dynos reproduce nearly the same result on multiple similar passes, but getting up to 12% difference from reality on a well calibrated dyno is not unusual. That difference does not matter when going relative, at it will just be the same offset on every graph. Not doing one means you are just going there for show.

If you just go want some power on a sheet, you will get exactly that. I call that the pleasing factor, aka "the customer just wants a big number on his sheet so i will please him by altering calibration and giving him a free 10 to 30% increase in horsepower".

[Croustibat]

It's made thru boost, a/f and timing.
All three are equally important and there's no magical number that is best for every set up even when set ups are very similar.

Actually yes there are.

Boost : What your turbo can safely do, or the max it can do if you dont care about its lifespan (even if it has poor efficiency, more is always better)

AFR : 12:1 [email protected]

timing : whatever is required to reach 95% combustion at 15°ATDC (and no det. You cant achieve that with regular gas, e85/race gas/methanol allows it). This depends on vacuum/boost and turbo efficiency of course. more air mass = faster burning. More boost requires LESS timing, which is the reason a lot of people make holes in their pistons when just adding boost and not remapping- they just det their engines to death.


This is how you achieve max power. However, for turbo reliability and ease of use, timing and boost are played with to get faster spool and limit torque in some areas, lowering efficiency. I am not going to give values here as this is what some people do for a living. That and it took me years to sort the truth from all the internet garbage you can find on most boards from people who dont know crap but are eager to show they do know something. Like you.


Finally AFR is leaned for better fuel consumption and emissions when not on WOT. But thats it. These are your magic numbers.

[Tom N]

Actually yes there are.

Boost : What your turbo can safely do, or the max it can do if you dont care about its lifespan (even if it has poor efficiency, more is always better)

AFR : 12:1 [email protected]

timing : whatever is required to reach 95% combustion at 15°ATDC (and no det. You cant achieve that with regular gas, e85/race gas/methanol allows it). This depends on vacuum/boost and turbo efficiency of course. more air mass = faster burning. More boost requires LESS timing, which is the reason a lot of people make holes in their pistons when just adding boost and not remapping- they just det their engines to death.


This is how you achieve max power. However, for turbo reliability and ease of use, timing and boost are played with to get faster spool and limit torque in some areas, lowering efficiency. I am not going to give values here as this is what some people do for a living. That and it took me years to sort the truth from all the internet garbage you can find on most boards from people who dont know crap but are eager to show they do know something. Like you.


Finally AFR is leaned for better fuel consumption and emissions when not on WOT. But thats it. These are your magic numbers.

Your right I don't know how to tune a car. LOL
I could type out a long winded reply of my accomplishments and the fact people come to me for dsm link tuning in this area but I won't. I know exactly how boost, a/f and timing go together. Tuning on race gas is easy. Tuning on pump gas not as easy. If you think all cars require the same a/f your wrong but I don't believe you think this. There is no set a/f and timing number that fits all set ups is what i'm saying. Quoting desired end results in the tune is not the same as one magical number that fits all, to plug into your cells on your tune. I didn't say there isn't a formula to tune by I said there isn't a magical number. You sure as hell aren't tuning most set ups to 12.1 here in florida on our pump gas if you want optimal results. No need to put words in my mouth I didn't say or turn them into something they aren't saying. Don't pretend to know someone. I have been doing this a long time.
Unlike you I'm not questioning your ability to tune a car as a I don't know you. You should try the same. I don't claim to be Dave Buschur or Tim Switcher but I have tuned my share of cars to limits past what most are able to achieve.

[Croustibat]

You didnt claim you were tuning cars, how could i question your ability about that ? Stop being paranoid dude.

I dont live in florida so that may be it. From a performance point of view i always map to 12 AFR, and so do other tuners i know. Because it works. When i need to go richer than that, it usually means the engine has some kind of problem, so i stand by this magic AFR number. Whatever boost/fuel is used, i always go 2 points richer than [email protected] for best power. No point in dumping more fuel in, the only reason det or temp go away when adding more fuel is because it changes combustion time. I did not do the maths, but a bit of googling will show someone who did. His conclusions were that you get the same result by changing timing. So i tried, and it proved to be true. I suggest you try too, you will see ;)

I agree timing is a different story ... and being where i live, i work with e85 fuel. 104 octane pump gas with huge cooling capacity FTW :D No probs on saying that makes things a lot easier, although it still brings its share of problems.

[jr_ss]

What Tom is saying is that not every car likes 12:1. Most 2jz's are tuned much richer than that. His personal car is running closer to 11:1 because that's what it liked. Not every car is the same and it sure as hell doesn't have anything to do with Florida.

[Tom N]

My DSM's on pump has would need to run A/F's in the 10's.

[Croustibat]

What Tom is saying is that not every car likes 12:1. Most 2jz's are tuned much richer than that. His personal car is running closer to 11:1 because that's what it liked. Not every car is the same and it sure as hell doesn't have anything to do with Florida.

And i am saying every engine does. I dont care if you got 2jz tuned like that, or DSMs that supposedly need that. That is just not true. Truth is a lot of tuner learned by themselves without really thinking about what they are doing. There is nothing wrong with that, but then it is better to understand what you are doing, and not just trusting what other people could say.

Now you should know that enthusiasts make penis contest with horsepower on single dyno runs. But did you know tuners make penis contest with the amount of timing they can set ? And boy did they found out running richer allowed more timing. They dont need to understand what it does, as they were always told more timing = more power. So the equation is more fuel = more timing = more power. Except ... well except running richer than 12:1 change combustion time and acts the same as retarding timing. But this is something tuners dont want to know.

So what is better ? Run suboptimal 10:1 or 11:1 so that your tuner can brag about the 2-3° more timing he could run on your engine ? Or running an optimal 12:1 with 2° less timing, but the same HP and less fuel consumption ?

The only reason to go richer is to protect the engine should a fuel component start to fail, and less fuel is sent. Because when that happens when running 11:1, you will still be in the 12:1 range. Running the optimal 12:1 though ... it means you are going into 13:1 / 14:1 territory at WOT and thats not good at all.

But performance wise, except bragging about how high the timing is set, there is no reason to run more than 12:1.

[Tom N]

Well I can say with absolute certainty that I've never in 20 years of doing this ever heard of tuners brag about the amount if timing they run? i myself dont care a whole lot about dyno numbers. im more of a track numbers person. In the DSM world most that tune know that to make power on pump gas you need to run minimal timing. I ran around single digit timing numbers on my 650hp GT35r set up. It sure as hell wasnt at 12:1 though. Tuners who do it for a living don't typically talk about the timing numbers at all. Timing is a big key in tying the higher boost levels and pump gas a/f together.
I my self have done lots of testing and running higher boost with more fuel and less timing always made more power. 12:1 on pump gas always required turning the boost down while running even less timing to keep detonation away which in turn made less power.
I will gladly pay the dyno time and supply the car for you to try making more power at 12:1 on pump gas. I can tell you it's already been tried though.

[Croustibat]

Thank you, but no thanks. The only pump gas i tune for is e85. Besides i live on the other side of the Atlantic, so you could not do that anyway ;)

[Tom N]

Thank you, but no thanks. The only pump gas i tune for is e85. Besides i live on the other side of the Atlantic, so you could not do that anyway ;)

I love E85 but its not available where I live. E85 tunes I do tend to tune around 12:1though.
But I was talking about regular 93 pump gas. Either way there is still no magical AFR that is the perfect number for all set ups.

Edit. Didn't notice you were in France. Feeling dumb offering for you to come by for some dyno sessions.
Offer is open though if you're ever in Florida. That's a friendly offer not a being a online asshole offer.

[Kingtal0n]

I love E85 but its not available where I live. E85 tunes I do tend to tune around 12:1though.
But I was talking about regular 93 pump gas. Either way there is still no magical AFR that is the perfect number for all set ups.

Edit. Didn't notice you were in France. Feeling dumb offering for you to come by for some dyno sessions.
Offer is open though if you're ever in Florida. That's a friendly offer not a being a online asshole offer.

where do you go? Theres a shop nearby that keeps a clean wideband and has a consistent roller. Its around 441 (state road 7) / I-595


The map based, factory turbo vehicles, have it made when it comes to SAFC tunes, even on pump gas. This because the difference in timing from 7psi->18psi is slight, and thats where you wind up when you double the injector size and pull map voltage to compensate.

[Tom N]

where do you go? Theres a shop nearby that keeps a clean wideband and has a consistent roller. Its around 441 (state road 7) / I-595


The map based, factory turbo vehicles, have it made when it comes to SAFC tunes, even on pump gas. This because the difference in timing from 7psi->18psi is slight, and thats where you wind up when you double the injector size and pull map voltage to compensate.

I'm in the Sarasota area. I have a few dynos I go to.
Depends if I need a awd dyno or not.

[Kingtal0n]

I'm in the Sarasota area. I have a few dynos I go to.
Depends if I need a awd dyno or not.

oh wow. I just picked up a 95 240sx from there. Its 3 hours away at 70mph