Something's not right. Possible meth problems....
Thread Starter
I'm Batman..
Joined: Apr 2014
Posts: 6,143
Likes: 921
From: Lehigh Acres FL
Tech Contributor
Drifting
Joined: Jul 2005
Posts: 1,646
Likes: 188
Just looked at the tune... I doubt it's the issue...
Fuel targets .86 lambda till about 4K then targets .85..
Spark is around 13-14 in high cylinder load (boost region) so timing looks fine...
The maf has lower g/sec values in the upper hz, but your running twin nozzle meth so the tuner pulled out fuel from the maf and based off your recent WB pulls with a single nozzle I think fuel is solid....
Start of injection is around 400 crank degrees... Thats real early but I've seen similiar in other boosted setups.... (I've never had to start it that early, but to each there own)
Peak tq is way high... Looked at DD and it matches... I would make sure this setup is going 100% throttle... Be a quick test
Few other things, but overall the tune looks pretty good IMO..
Fuel targets .86 lambda till about 4K then targets .85..
Spark is around 13-14 in high cylinder load (boost region) so timing looks fine...
The maf has lower g/sec values in the upper hz, but your running twin nozzle meth so the tuner pulled out fuel from the maf and based off your recent WB pulls with a single nozzle I think fuel is solid....
Start of injection is around 400 crank degrees... Thats real early but I've seen similiar in other boosted setups.... (I've never had to start it that early, but to each there own)
Peak tq is way high... Looked at DD and it matches... I would make sure this setup is going 100% throttle... Be a quick test
Few other things, but overall the tune looks pretty good IMO..
Thread Starter
I'm Batman..
Joined: Apr 2014
Posts: 6,143
Likes: 921
From: Lehigh Acres FL
Tech Contributor
Just looked at the tune... I doubt it's the issue...
Fuel targets .86 lambda till about 4K then targets .85..
Spark is around 13-14 in high cylinder load (boost region) so timing looks fine...
The maf has lower g/sec values in the upper hz, but your running twin nozzle meth so the tuner pulled out fuel from the maf and based off your recent WB pulls with a single nozzle I think fuel is solid....
Start of injection is around 400 crank degrees... Thats real early but I've seen similiar in other boosted setups.... (I've never had to start it that early, but to each there own)
Peak tq is way high... Looked at DD and it matches... I would make sure this setup is going 100% throttle... Be a quick test
Few other things, but overall the tune looks pretty good IMO..
Fuel targets .86 lambda till about 4K then targets .85..
Spark is around 13-14 in high cylinder load (boost region) so timing looks fine...
The maf has lower g/sec values in the upper hz, but your running twin nozzle meth so the tuner pulled out fuel from the maf and based off your recent WB pulls with a single nozzle I think fuel is solid....
Start of injection is around 400 crank degrees... Thats real early but I've seen similiar in other boosted setups.... (I've never had to start it that early, but to each there own)
Peak tq is way high... Looked at DD and it matches... I would make sure this setup is going 100% throttle... Be a quick test
Few other things, but overall the tune looks pretty good IMO..
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
Just looked at the tune... I doubt it's the issue...
Fuel targets .86 lambda till about 4K then targets .85..
Spark is around 13-14 in high cylinder load (boost region) so timing looks fine...
The maf has lower g/sec values in the upper hz, but your running twin nozzle meth so the tuner pulled out fuel from the maf and based off your recent WB pulls with a single nozzle I think fuel is solid....
Start of injection is around 400 crank degrees... Thats real early but I've seen similiar in other boosted setups.... (I've never had to start it that early, but to each there own)
Peak tq is way high... Looked at DD and it matches... I would make sure this setup is going 100% throttle... Be a quick test
Few other things, but overall the tune looks pretty good IMO..
Fuel targets .86 lambda till about 4K then targets .85..
Spark is around 13-14 in high cylinder load (boost region) so timing looks fine...
The maf has lower g/sec values in the upper hz, but your running twin nozzle meth so the tuner pulled out fuel from the maf and based off your recent WB pulls with a single nozzle I think fuel is solid....
Start of injection is around 400 crank degrees... Thats real early but I've seen similiar in other boosted setups.... (I've never had to start it that early, but to each there own)
Peak tq is way high... Looked at DD and it matches... I would make sure this setup is going 100% throttle... Be a quick test
Few other things, but overall the tune looks pretty good IMO..
would love to see a log with injector duty cycle, rail pressure, fuel pressure, spark and spark retard, etc.
Last edited by Higgs Boson; Jan 3, 2016 at 08:30 PM.
Drifting
Joined: Jul 2005
Posts: 1,646
Likes: 188
Hook up the 2nd nozzle and record lambda or AFR, that will tell us that.. The ECU is commanding less fuel that a factory c7 at WOT, but I believe the tuner pulled out fuel to compensate for much meth... Hard to tell that by looking, but the WV will tell the tell..
SOI does look early like I mentioned.. I've had good luck on similiar builds shooting for 360 crank degrees, Never tried it in the 400+ range to know, but Higgs could be right on with that!!
I usually setup 93/meth cars for 12-14 degrees of timing personally
I agree with Higgs.... It would seem rail pressure was dropping off considering such high SOI, BUT your really not commanding a lot of fuel from the ECU, rather your getting it from meth... Never run out of meth in that rig...
SOI does look early like I mentioned.. I've had good luck on similiar builds shooting for 360 crank degrees, Never tried it in the 400+ range to know, but Higgs could be right on with that!!
I usually setup 93/meth cars for 12-14 degrees of timing personally
I agree with Higgs.... It would seem rail pressure was dropping off considering such high SOI, BUT your really not commanding a lot of fuel from the ECU, rather your getting it from meth... Never run out of meth in that rig...
Thread Starter
I'm Batman..
Joined: Apr 2014
Posts: 6,143
Likes: 921
From: Lehigh Acres FL
Tech Contributor
Hook up the 2nd nozzle and record lambda or AFR, that will tell us that.. The ECU is commanding less fuel that a factory c7 at WOT, but I believe the tuner pulled out fuel to compensate for much meth... Hard to tell that by looking, but the WV will tell the tell..
SOI does look early like I mentioned.. I've had good luck on similiar builds shooting for 360 crank degrees, Never tried it in the 400+ range to know, but Higgs could be right on with that!!
I usually setup 93/meth cars for 12-14 degrees of timing personally
I agree with Higgs.... It would seem rail pressure was dropping off considering such high SOI, BUT your really not commanding a lot of fuel from the ECU, rather your getting it from meth... Never run out of meth in that rig...
SOI does look early like I mentioned.. I've had good luck on similiar builds shooting for 360 crank degrees, Never tried it in the 400+ range to know, but Higgs could be right on with that!!
I usually setup 93/meth cars for 12-14 degrees of timing personally
I agree with Higgs.... It would seem rail pressure was dropping off considering such high SOI, BUT your really not commanding a lot of fuel from the ECU, rather your getting it from meth... Never run out of meth in that rig...
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
I am willing to bet it was either set up blind off another tune (copy/paste) or it was tuned off meth first and then reset the MAF curve while spraying.
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
Do you still have the HPT and cable? I can email you a config or two to log with while you make some runs.
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Thread Starter
I'm Batman..
Joined: Apr 2014
Posts: 6,143
Likes: 921
From: Lehigh Acres FL
Tech Contributor
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
Dazed Confused & Verklemp
Joined: May 2008
Posts: 1,400
Likes: 110
From: Naples, FL & Clear Lake, IA
Looks like you pulled the tune after I got all the information. Glad it's working.
Dazed Confused & Verklemp
Joined: May 2008
Posts: 1,400
Likes: 110
From: Naples, FL & Clear Lake, IA
i think it's too lean, too much timing, and start of injection is too early. he is blowing fuel out of an open exhaust valve, spraying through the spark and the ECM is pulling timing down towards TDC to try to prevent it and is probably even lighting after TDC.... it's leaning out because it's out of injector. the tune is commanded lean to try and preserve injector but it's not working.
would love to see a log with injector duty cycle, rail pressure, fuel pressure, spark and spark retard, etc.
would love to see a log with injector duty cycle, rail pressure, fuel pressure, spark and spark retard, etc.
How many items can be logged simultaneously with HP Tuners Pro?
Hoping that Ant can get his Innovate plugged in to analog port on my HP Tuner Pro. Eventually want to set up an Innovate on my Vette once I get a bigger urge to add headers, tune + E-85.
Thread Starter
I'm Batman..
Joined: Apr 2014
Posts: 6,143
Likes: 921
From: Lehigh Acres FL
Tech Contributor
Ok.. This may be the update everyone is waiting on.. lol
I've been working with Higgs in the background on this to try and figure things out and we may have it close to being the way it should be. HUGE THANKS TO HIGGS for taking time to look at this for me! I got home today, and put my second meth nozzle back on and also swapped out my new plug wires. Took the car out and did a run and Lambda came in around .89-.90 at WOT. Still toooo lean. Meth was at level 6 mind you, which is where I am tuned at. Higgs had me put the meth at level 8 and redo another pull. I did that, and now the Lambda is between .80-.84, which is right where it should be. AND, the car is not making that weird sound anymore!
I've done a handful of pulls so far and the sound has not returned yet. It would see as though the sound I was hearing may have been the ECM retarding things due to the lean condition. I am going to take the car out tomorrow night after work and put it through some paces to really test it out and if all looks good then there are a few changes I will need to get with my tuner on, but overall it should be fixed!
I've been working with Higgs in the background on this to try and figure things out and we may have it close to being the way it should be. HUGE THANKS TO HIGGS for taking time to look at this for me! I got home today, and put my second meth nozzle back on and also swapped out my new plug wires. Took the car out and did a run and Lambda came in around .89-.90 at WOT. Still toooo lean. Meth was at level 6 mind you, which is where I am tuned at. Higgs had me put the meth at level 8 and redo another pull. I did that, and now the Lambda is between .80-.84, which is right where it should be. AND, the car is not making that weird sound anymore!
I've done a handful of pulls so far and the sound has not returned yet. It would see as though the sound I was hearing may have been the ECM retarding things due to the lean condition. I am going to take the car out tomorrow night after work and put it through some paces to really test it out and if all looks good then there are a few changes I will need to get with my tuner on, but overall it should be fixed!
Last edited by FYREANT; Jan 4, 2016 at 10:48 PM.
Melting Slicks
Joined: Dec 1999
Posts: 2,049
Likes: 702
From: Tulsa, Ok
I know you're close to maxing out the stock fuel system but one 15gph nozzle should do the trick. I think the AFR needs to be tweaked a bit. You don't want to be dependent on meth to that degree.
If it were me, I'd bump the initial pressure a bit, be sure the turn on is at 3psi and set the gain back to around 6 AND go back to one 15 gph nozzle. Then get a retune around those parameters. Now you have your own wideband and can watch over things closely.
One 15 gph will spray 5.33 fluid oz in a 10 second pass.
If it were me, I'd bump the initial pressure a bit, be sure the turn on is at 3psi and set the gain back to around 6 AND go back to one 15 gph nozzle. Then get a retune around those parameters. Now you have your own wideband and can watch over things closely.
One 15 gph will spray 5.33 fluid oz in a 10 second pass.
Last edited by imxz28; Jan 5, 2016 at 12:45 PM.