Correct A/F Ratio...
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From: Mont Belvieu, Tx.
Originally Posted by Patrick G
My car is SD tuned as well, but I don't like doing long 4th gear pulls on the street. 7000 rpm in 4th gear for me is over 150mph! 2nd or 3rd gear pulls on the street don't load the motor as well as 4th gear pulls. That's why I use the Mustang dyno. 4th gear pulls on the MD take as long as 4th gear pulls on the street, I can make instant, real-time timing and fuel changes with my EFI Live Roadrunner Emulator, and I never have to worry about speeding tickets or accidents. In my experience, there is no change in A/F ratio going from the Mustang Dyno to the street.
Yeah 880+ RWHP 4th gear roll ons on the street is a little nerve racking for my tuner in the passenger seat...
...is that right Eric??I'm glad I live in the boonies so I can stretch the SS legs a little...
Originally Posted by DJ's99SS
Looks like I'll be heading back to the MD at Conley's...I didn't realize the Mustang Dyno's where that close to "real world" street runs...
Yeah 880+ RWHP 4th gear roll ons on the street is a little nerve racking for my tuner in the passenger seat... ...is that right Eric??
I'm glad I live in the boonies so I can stretch the SS legs a little...
Yeah 880+ RWHP 4th gear roll ons on the street is a little nerve racking for my tuner in the passenger seat...
...is that right Eric??I'm glad I live in the boonies so I can stretch the SS legs a little...
880 
Originally Posted by JMBLOWNWS6
HAHAHA Nothing like getting your neck snapped while trying to modify the PE and VE tables 880
880 Thread Starter
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From: Mont Belvieu, Tx.
Originally Posted by bygblok
pretty bad when the tuner guys are going to have to start wearing a HAANS device!!
...I think handing them additional safety equip. like that will probably scare the sh** out of any tuners that dare step foot in your car...I can see the looks on their face right now...lolYeh 880 blowin' through the clutch in Dallas with 115 degree temps in the shop during the pulls. So with the new Textralia DD and A/F where it needs to be, we should be 1xxx with no prob.
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From: Mont Belvieu, Tx.
One more thing I wanted to pick everyone's brains about is if we "lean" on our cars a tad with this summer air and we then get into the cooler part of the season with nice cool, dense air...are we looking at too lean of a condition from the tune we've had with the hot, humid air?
I don't really know how much the AFR can change with good air. I'm thinking maybe from a 11.7 to 12.0? Or is it more dramatic than that...? I know its a general statement but I really don't want to keep having to change the damn tune several times a year depending on air quality...yeh I know can't have your cake and eat it too.
I don't really know how much the AFR can change with good air. I'm thinking maybe from a 11.7 to 12.0? Or is it more dramatic than that...? I know its a general statement but I really don't want to keep having to change the damn tune several times a year depending on air quality...yeh I know can't have your cake and eat it too.
Last edited by DJ's99SS; Aug 30, 2006 at 08:19 PM.
..... The whole tune was done on the street. Only thing the dyno was for was for #'s. You also have to look at the drivers habbits. Dennis is a street racer who likes to take down supras etc up to some high speeds. So as IAT's go up he needs to maintain a lower AFR to compensate for that. Its not a track car that sits for a while after a run. Dennis is bascially hot lapping the car when he goes out. So it needs to be where it is 11.0-11.2. The heads were being cleaned up due to some coopper gaskets that dont seem to be working very well. The machine shop said he should have it around 12.5 and I was like say bye to the motor. I run my boosted car at 11.7 but Im constantly watching my tune and AFR. Anyhow thats where the whole thread came from I figured everyone should know the background of it. Its fun riding in that car. Im use to it already between my car, tiagos, and Dennis'. Not to take anything away from dennis car its a hell of a ride but Im use to it plus Im trying to stare at the wide band and the laptop at the same time. Also trust me dennis's car is insane when it comes to the power onset there is no power curve its a straight line (regardless of RPM) up then it goes flatline to the right. I wont say I know everything so I m open to anyones opinion not trying to prove anyone wrong. Overall the car is where I would like it to be.
Originally Posted by JMBLOWNWS6
With his car being in SD and not a MAF tune I reconmend tuning it on the street. There no better way to do it IMHO. Ive use a dynojet and I have seen AFR's leaner on the street under load than on the dyno on a WOT. As long as you have a wideband installed in the car tune it on the street. Im using HP tuners with the RTT and the output from the wideband into the scanner 
Last edited by ESR; Aug 30, 2006 at 05:26 PM.
I prefer street tuning.As for A/F it depends on each car.Ussually 12.5-1 A/F for NA cars work for me.
As for the fun of street tuning,I like it. Last spring I was doing PurEvl's 800hp/800tq car on 40 degree days.We could only do 5th gear pulls because 4th would spin.Nothing like 80mph to 170mph pulls down the highway
As for the fun of street tuning,I like it. Last spring I was doing PurEvl's 800hp/800tq car on 40 degree days.We could only do 5th gear pulls because 4th would spin.Nothing like 80mph to 170mph pulls down the highway
Im sure you know but the car is an FI car for clarification.
Originally Posted by Slowhawk
I prefer street tuning.As for A/F it depends on each car.Ussually 12.5-1 A/F for NA cars work for me.
As for the fun of street tuning,I like it. Last spring I was doing PurEvl's 800hp/800tq car on 40 degree days.We could only do 5th gear pulls because 4th would spin.Nothing like 80mph to 170mph pulls down the highway
As for the fun of street tuning,I like it. Last spring I was doing PurEvl's 800hp/800tq car on 40 degree days.We could only do 5th gear pulls because 4th would spin.Nothing like 80mph to 170mph pulls down the highway
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Originally Posted by ESR
Im sure you know but the car is an FI car for clarification.
Sorry, 11.5-1 for FI. Ussually timing and A/F dictates together for FI.You can run 12.5-1 with lower timing or a richer 11.5-1 with more timing.I like more timing since it seams to have more of an affect than A/F.
People that say they gain a ton when leaning out the A/F are more than likely not running enough timing
Originally Posted by Slowhawk
Sorry, 11.5-1 for FI. Ussually timing and A/F dictates together for FI.You can run 12.5-1 with lower timing or a richer 11.5-1 with more timing.I like more timing since it seams to have more of an affect than A/F.
People that say they gain a ton when leaning out the A/F are more than likely not running enough timing
People that say they gain a ton when leaning out the A/F are more than likely not running enough timing
I agree. People ask me how much timing I run, im like about 25.
ON FI? OMG!
Yeah, no problem. Just keep it rich. Timing = power....rich = safe.
Originally Posted by Patrick G
Jarrod, I need to show you some of my dyno sheets. We've done a lot of tuning recently on a local Mustang dyno and have had great success by giving the motor around 12.8:1 from 2000-4000 rpm, then richening it up to 12.5:1 at peak torque (4500-5400 area) than gradually leaning it out to 13.0-13.2:1 A/F ratio. We've done the same with timing. A little more in the 3500-4500 range, less in the 4500-5400 range, then more toward peak power. For us, it's all about running the most cylinder pressure we can on pump gas and living. More tuning is in order as I want my car to live for those long 1 mile blasts during the upcoming Texas Mile in October. For this kind of tuning, the Mustang dyno is sooooo much better than the Dynojet. WOT pulls take about 8 seconds on the DJ and around 19 seconds on the Mustang. The MD replicates the street a lot better than the DJ.
One final note: The wide band O2 sensor reads much more accurately when placed in a bung just past the header collector. When shoved up the tailpipe, I've seen them read more than a point leaner than they really are. As a result, people that are tuning for 12.5:1 A/F ratio at the tailpipe are actually giving the motor 11.5:1 when read at the header collector. Something to think about.
One final note: The wide band O2 sensor reads much more accurately when placed in a bung just past the header collector. When shoved up the tailpipe, I've seen them read more than a point leaner than they really are. As a result, people that are tuning for 12.5:1 A/F ratio at the tailpipe are actually giving the motor 11.5:1 when read at the header collector. Something to think about.
What do you recommend with the AFR and Timing after Peak HP to help keep the HP from falling off to fast?
Bob
Originally Posted by J-Rod
One thing I also see no one doing is to make their tune fatter at TQ peak, and to roll the A/F leaner as they roll towards HP peak. As an example on an N/A motor going from 12.2 - 12.5 at peak Tq to say 13.5 at peak Hp. You motor needs fuel at peak Tq, but it doesn't need the same ammount of fuel at Peak HP.
All my tunes do this, In fact, those are pretty close to the exact #'s I shoot for
Originally Posted by SlickVert
Patrick great info!
What do you recommend with the AFR and Timing after Peak HP to help keep the HP from falling off to fast?
Bob
What do you recommend with the AFR and Timing after Peak HP to help keep the HP from falling off to fast?
Bob
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
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2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
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Originally Posted by ESR
The whole tune was done on the street. Only thing the dyno was for was for #'s. You also have to look at the drivers habbits. Dennis is a street racer who likes to take down supras etc up to some high speeds. So as IAT's go up he needs to maintain a lower AFR to compensate for that. Its not a track car that sits for a while after a run. Dennis is bascially hot lapping the car when he goes out. So it needs to be where it is 11.0-11.2. The heads were being cleaned up due to some coopper gaskets that dont seem to be working very well. The machine shop said he should have it around 12.5 and I was like say bye to the motor. I run my boosted car at 11.7 but Im constantly watching my tune and AFR. Anyhow thats where the whole thread came from I figured everyone should know the background of it. Its fun riding in that car. Im use to it already between my car, tiagos, and Dennis'. Not to take anything away from dennis car its a hell of a ride but Im use to it plus Im trying to stare at the wide band and the laptop at the same time. Also trust me dennis's car is insane when it comes to the power onset there is no power curve its a straight line (regardless of RPM) up then it goes flatline to the right. I wont say I know everything so I m open to anyones opinion not trying to prove anyone wrong. Overall the car is where I would like it to be.
My car was set @ 11.1 to 11.3 after we were all said and done. It ran fine and was a monster on the road. Im going to a 3 bar tune with a turbo kit and have alot to learn still. Im more of a grease monkey that just started to learn tuning. Nothing like building your car start to finish and tuning it also 
Last edited by JMBLOWNWS6; Sep 10, 2006 at 05:35 AM.
Originally Posted by Steel Chicken
I agree. People ask me how much timing I run, im like about 25.
ON FI? OMG!
Yeah, no problem. Just keep it rich. Timing = power....rich = safe.
ON FI? OMG!
Yeah, no problem. Just keep it rich. Timing = power....rich = safe.
Last edited by JMBLOWNWS6; Sep 10, 2006 at 05:35 AM.
.... Trust me no offense taken. Im very open minded to other peoples opinions. Ill never say I know it all. Taking other peoples idea into consideration can only make you better. I only wanted give some background to Dennis' car.
Originally Posted by JMBLOWNWS6
This is the problem I have with my air to water setup on my car. The IAT's(Yes it is relocated to the correct place) get to hot and the AFR begins to suffer(Hotlapping) This the reason I told him its important. Im not knocking your tuning skills at all. Ive seen what you have done and these SD tunes arent for rookies. My car was set @ 11.1 to 11.3 after we were all said and done. It ran fine and was a monster on the road. Im going to a 3 bar tune with a turbo kit and have alot to learn still. Im more of a grease monkey that just started to learn tuning. Nothing like building your car start to finish and tuning it also
My car was set @ 11.1 to 11.3 after we were all said and done. It ran fine and was a monster on the road. Im going to a 3 bar tune with a turbo kit and have alot to learn still. Im more of a grease monkey that just started to learn tuning. Nothing like building your car start to finish and tuning it also 
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From: uae -dubai
I offen tune cars her with Microtech ECU ,so you can check this :
6.0 - Rich burnlimit
9.0 - Black smoke/lowpower
11.5 - Approximate rich best torque at wide open throttle
12.2 - Safe best power at wide open throttle
13.3 - Aproximate lean best torque
14.7 - Stoichimetric AFR best for idel and cruse
15.5 - lean cruis
16.5 - Usual best economy
18.0 - Carburated lean bern limit
22+ - Lean lean lean warning
saoud
6.0 - Rich burnlimit
9.0 - Black smoke/lowpower
11.5 - Approximate rich best torque at wide open throttle
12.2 - Safe best power at wide open throttle
13.3 - Aproximate lean best torque
14.7 - Stoichimetric AFR best for idel and cruse
15.5 - lean cruis
16.5 - Usual best economy
18.0 - Carburated lean bern limit
22+ - Lean lean lean warning
saoud Thread Starter
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From: Mont Belvieu, Tx.
I'm guessing this is an approximate for N/A not FI set ups. So anywhere in the 10's at WOT is too rich I assume with a loss in power??
Originally Posted by Y2K
I offen tune cars her with Microtech ECU ,so you can check this :
6.0 - Rich burnlimit
9.0 - Black smoke/lowpower
11.5 - Approximate rich best torque at wide open throttle
12.2 - Safe best power at wide open throttle
13.3 - Aproximate lean best torque
14.7 - Stoichimetric AFR best for idel and cruse
15.5 - lean cruis
16.5 - Usual best economy
18.0 - Carburated lean bern limit
22+ - Lean lean lean warning
saoud
6.0 - Rich burnlimit
9.0 - Black smoke/lowpower
11.5 - Approximate rich best torque at wide open throttle
12.2 - Safe best power at wide open throttle
13.3 - Aproximate lean best torque
14.7 - Stoichimetric AFR best for idel and cruse
15.5 - lean cruis
16.5 - Usual best economy
18.0 - Carburated lean bern limit
22+ - Lean lean lean warning
saoud
So anywhere in the 10's at WOT is too rich I assume with a loss in power??
I too have had the best payoff with a little more spark and fuel at the torque peak, and a little less fuel with a little more spark at peak HP.
On my FI setup, I am running a 12.0 AFR at peak torque, and 12.2 at peak HP. This is at relatively low boost (7.5# after the FMIC and throttle) since my 383 outgrew the Vortech V-2 S-trim before it was strapped on.
I am experimenting with hi-vacuum, lo-load cruise AFR's of 15.75-16.00 right now to try to squeeze the most mileage out of her. The MPG has gone up from a very safe tune mpg of 13 to a present 18mpg. The plugs look great.
LS1TECH.COM is my favorite FI and technical forum.
Jim
Teching In
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Check out Innovate's website on tuning tips. On our Mustang dyno we do almost all of our tuning by our LM-1. We go for 12.8:1 (it is hooked into the dyno, so we can see it on power pulls over the RPM range). We have talked a lot with Hans over at Innovate and he is very active in their forums as far as answering tuning questions. Going off of their recomendations, there should be no difference between a N/A motor and a boosted motor, be it turbo or blower. Once we get our AFRs set, we move onto timing. The reason most of the boosted motors run richer is to put less heat into the heads. If everyone was reverse cooled, power and torque would be easier, and using pump gas. Being able to run the head cooler is like added compression (and torque) for free.