Timing Question

[turpdogg]

I have a 97 GSX with a 1st gen head/throttlebody, 550cc injectors, walboro 255 fuel pump Apexi SAFC, TD05 20G (machined out compressor housing) FMIC etc....etc.... Anyways I finaly got my datalogger from pocketlogger.com and during 3rd gear pulls the most timing I can get in +13 at 6000-7000RPMs. The 02 readings are at 1.00V but if I go any leaner (.98 or below) I only get +10/11 degree's at that same RPM. 2nd gear pulls I can get +14 degree's but thats still at 1.00V. Any suggestions?

WHen I did my first run I was running CRAZY rich, 1.04V and only getting 9 or 10 degrees timing so I have improved. I just keep reading peoples stuff saying they are getting +15/16 degrees. Any suggestions?

 

[kpt4321]

If you use the SAFC to run really rich, you get a higher airflow signal and you will get less timing advance.

 

[turpdogg]

Dude? What are you talking about? I'm not using the AFC to run rich, I'm leaning things out???

 

[nine5raptor]

Originally posted by turpdogg
Any suggestions?

Ignore 02 voltages.
Use higher octane fuel.
Go with the setting that gives you the best timing.

 

[kpt4321]

Originally posted by turpdogg
Dude? What are you talking about? I'm not using the AFC to run rich, I'm leaning things out???

Originally posted by turpdogg
I was running CRAZY rich, 1.04V and only getting 9 or 10 degrees timing

When you first started, you didn't have a lot of advance because the airflow signal was so high, and thus you were also rich.

 

[turpdogg]

The "running rich" statement was before any tuning. I knew I needed to lean things out from the get-go. Just wanted to know why I can only get 13 degrees in a 3rd gear pull. I'm in the U.S. Air Force stationed in England and the gas over here starts at 95 octane and goes to 98. But as you can imagine it cost over $5.00 a gallon over here. I alway laugh at my friends back in the states that whine about paying $1.90 a gallon ha ha ha.

 

[nine5raptor]

Is it rated in RON, MON, or (R+M)/2? This will change how you compare octanes.

 

[Defiant]

Originally posted by turpdogg
I'm in the U.S. Air Force stationed in England and the gas over here starts at 95 octane and goes to 98. But as you can imagine it cost over $5.00 a gallon over here. I alway laugh at my friends back in the states that whine about paying $1.90 a gallon ha ha ha.

Pump price. How much of that is tax?

 

[turpdogg]

Its rated in RON.


Is it rated in RON, MON, or (R+M)/2? This will change how you compare octanes

 

[44pirate]

O2's higher then .98 will give you knock and pull timing on a wot pull.
What are your Hi throttle settings on your SAFC.
They better be at least -20 with that amount of Octane. Just my .02

 

[nine5raptor]

Originally posted by turpdogg
Its rated in RON.

Ok. RON and MON tend to be less than 15 'octanes' apart. So if you compare your 95 RON to our (R+M)/2, worst case is it is equal to about 88 octane here. If you are a little more optimistic, it is around 91 (assuming a gap of ~6 b/w RON and MON for your particular gas).

For the 98, think of it as somewhere b/w 91 and 94.

This is why you have to run richer.

 

[turpdogg]

Originally posted by nine5raptor
Ok. RON and MON tend to be less than 15 'octanes' apart. So if you compare your 95 RON to our (R+M)/2, worst case is it is equal to about 88 octane here. If you are a little more optimistic, it is around 91 (assuming a gap of ~6 b/w RON and MON for your particular gas).

For the 98, think of it as somewhere b/w 91 and 94.

This is why you have to run richer.

Makes sense sine I have been tuning using the 95 instead of the 98 (Optimax) fuel. Guess I'll try some Octane booster then. Like I said, anything below a 1.00 and I get my timing pulled. BTW I'm at -30's at some of the RPMs. The car feels much better now, I can't believe how rich I was running before the datalogger. Now I just need some good fuel.

 

[turpdogg]

Originally posted by turpdogg
Makes sense sine I have been tuning using the 95 instead of the 98 (Optimax) fuel. Guess I'll try some Octane booster then. Like I said, anything below a 1.00 and I get my timing pulled. BTW I'm at -30's at some of the RPMs. The car feels much better now, I can't believe how rich I was running before the datalogger. Now I just need some good fuel.

Also do you know of any links to sites that compare the RON/R+M fuels?

 

[td06hkiko]

You should be Getting 16-17 degs of timming. How much boost are you trying to tune for? Remember once your STFT and LTFT's are set ,you should leave them alone. You should be close to 0 plus or minus 1. Your LO settings on the AFC control those. NOw, Your HI, controls your WOT. When you make 3rd gear pulls you should be at WOT 3000rpm all the way till about 6500. Once you've done this find where your timming gets pulled and where it starts to climb. When it climbs it should be very steady(Smooth acending curve). From 3000 on up you should see something like 10, 10,11,12,13, 13, 14,15,15,16, 17. IF you see the Dip that's where you add fuel, on that rpm. One click at a time on the AFC. At 5000 rpm is where it gets critical. Watch your timing at 5000 rpm you should be well above 13 degs and no less than 12. Hope this helps out.

KIKO

Originally posted by turpdogg
I have a 97 GSX with a 1st gen head/throttlebody, 550cc injectors, walboro 255 fuel pump Apexi SAFC, TD05 20G (machined out compressor housing) FMIC etc....etc.... Anyways I finaly got my datalogger from pocketlogger.com and during 3rd gear pulls the most timing I can get in +13 at 6000-7000RPMs. The 02 readings are at 1.00V but if I go any leaner (.98 or below) I only get +10/11 degree's at that same RPM. 2nd gear pulls I can get +14 degree's but thats still at 1.00V. Any suggestions?

WHen I did my first run I was running CRAZY rich, 1.04V and only getting 9 or 10 degrees timing so I have improved. I just keep reading peoples stuff saying they are getting +15/16 degrees. Any suggestions?

 

[turpdogg]

Originally posted by td06hkiko
You should be Getting 16-17 degs of timming. How much boost are you trying to tune for? Remember once your STFT and LTFT's are set ,you should leave them alone. You should be close to 0 plus or minus 1. Your LO settings on the AFC control those. NOw, Your HI, controls your WOT. When you make 3rd gear pulls you should be at WOT 3000rpm all the way till about 6500. Once you've done this find where your timming gets pulled and where it starts to climb. When it climbs it should be very steady(Smooth acending curve). From 3000 on up you should see something like 10, 10,11,12,13, 13, 14,15,15,16, 17. IF you see the Dip that's where you add fuel, on that rpm. One click at a time on the AFC. At 5000 rpm is where it gets critical. Watch your timing at 5000 rpm you should be well above 13 degs and no less than 12. Hope this helps out.

KIKO

Got it now, I had to reduce my boost to 17PSI. Now I get 16 degrees of timing @6000RPMs. Thanks guys.