2005 GTO TT won't rev past 5000rpms under load.

[jray1]

As the title says I am having a hard time getting the car to run past 5000rpms. It builds up to around 10psi of boost and then it's like I threw an anchor out. Still has fuel as best I can tell by the afr reading. Did notice about 0.5 knock showing up. Running twin 68/70's and using the cxracing intercooler and piping. Running speed density. I am wondering if it's the heat here in north Alabama right now that's causing some of the issue. Still new to tuning so still trying to learn all I can. Also not easy to start back up when hot. Any ideas? Tried some different plugs today BR7's gapped to .025. ran worse at idle and same up top not going past 5k.

[5FDP]

If you don't post your tune and logs file, we can't really help you.

A full list of mods would be helpful as well.

[jray1]

If you don't post your tune and logs file, we can't really help you.

A full list of mods would be helpful as well.

Sorry got a little trigger happy. 🤣 LS2 forged bottom -10cc pistons. Twin 68/70 turbos, twin 450L's in tank fuel pumps one is on a Hobbs switch coming on at about 4psi boost. Dekka 80 injectors on a return system sitting on 58psi fuel pressure with a 1:1 boost reference pressure regulator.

[jray1]

I will have to upload a more current log but it was doing the same thing in this one. Also made a few tweaks in the tune file I will upload the latest this afternoon.

[Lakegoat]

Your VE tables (both) are wayyy off. Look at the 3D model. PE should have Delay 0. EQ Ratio-- gas and boost 1.27 across. TQ Mgt--ETC Limits 100 all except the first row which will be zero. FUEL--flow rate is wrong, look up the flow rate for 58npsi or 400kpa. Offset vs Volts vs VAC is wrong. If that is the correct table for those injectors, the 0 column number will be the same across in each row for a boost referenced system.
Here is a screenshot of my Primary VE table. Yours needs to be smoothed a little.

[jray1]

Your VE tables (both) are wayyy off. Look at the 3D model. PE should have Delay 0. EQ Ratio-- gas and boost 1.27 across. TQ Mgt--ETC Limits 100 all except the first row which will be zero. FUEL--flow rate is wrong, look up the flow rate for 58npsi or 400kpa. Offset vs Volts vs VAC is wrong. If that is the correct table for those injectors, the 0 column number will be the same across in each row for a boost referenced system.
Here is a screenshot of my Primary VE table. Yours needs to be smoothed a little.

Some of this I am not sure what you are talking about. Some of the data in my tune is from one of my GTO buddies that is running the same set up as far as turbos and injectors. I don't remember changing anything in the offset vs volts vs VAC so I will need to dive into that a little more. Lost on what you are talking about with the flow rate at 58npsi? Can you elaborate a little more please? I knew my ve tables would need work but I need to be able to drive and start dialing them in. I smoothed them out a bunch in the current tune but still need a ton of work. There again I need to be a little more drivable before I am sure about the changes I make. I will upload the current tune and a log from yesterday this afternoon. Thank you for the help!

[Lakegoat]

You said your fuel pressure was 58#. The Dekka website shows numbers for 43psi or 300kpa. Your ifr chart shows 38 across for a 76# injector. At 58 psi, your injectors should flow about 87# which would be 43.5# instead of 38 in the chart. (double stoich) . (I don't know if that is the correct# for those injectors--just a guess) Your short pulse adder, minimum pulse and offset has to be correct in order for you to tune your engine correctly. What MAP sensor do you have that has a Linear of 250?
This is your Primary VE in 3D. Needs to be a lot smoother. The big peaks come from copying the whole graph and pasting it. That will show allof the lean spikes when you get off the gas. At least push them down manually with the cursor before hitting smooth.
Your PE EQ numbers should be what you are shooting for in wot Lambda. 14.6 divided by 1.27 is 11.5 afr or .787 Lambda. If the numbers in the chart are wrong, your EQ Error graph is going to be wrong that you use to adjust your VE table.

[jray1]

You said your fuel pressure was 58#. The Dekka website shows numbers for 43psi or 300kpa. Your ifr chart shows 38 across for a 76# injector. At 58 psi, your injectors should flow about 87# which would be 43.5# instead of 38 in the chart. (double stoich) . (I don't know if that is the correct# for those injectors--just a guess) Your short pulse adder, minimum pulse and offset has to be correct in order for you to tune your engine correctly. What MAP sensor do you have that has a Linear of 250?
This is your Primary VE in 3D. Needs to be a lot smoother. The big peaks come from copying the whole graph and pasting it. That will show allof the lean spikes when you get off the gas. At least push them down manually with the cursor before hitting smooth.
Your PE EQ numbers should be what you are shooting for in wot Lambda. 14.6 divided by 1.27 is 11.5 afr or .787 Lambda. If the numbers in the chart are wrong, your EQ Error graph is going to be wrong that you use to adjust your VE table.

Yes the 38 across on flow rate got me down to where I was not so crazy rich at idle. Using the tick Corvette 2.5bar map sensor.

[Lakegoat]

That's not how you lean out the idle. The data numbers for the injectors must be as the mfg lists them. Then tune the ve table.
That map sensor linear is 250, Linear B is 83.33, Offset is 10.00. Those numbers need to be correct.

[jray1]

I will correct that in the tune tomorrow. Thank you for the info. I have all the injector data except the flow rate at 58 psi I will search that in the morning before work.

[jray1]

Dropped the fuel pressure down to 43psi and put the flow rate to 40. Majorly smoothed out the ve tables and yes my boost histogram was set up wrong, thank you for pointing that out. Got a run in just now. Got a few more RPMs and more boost. Will upload the log when I get the laptop back on wifi.

[jray1]

Updated tune now in car, hot start is even better!

[jray1]

Log file after tune work.

[Lakegoat]

Good! Here is the OFFSET vs Volts vs VAC under fuel that I mentioned above. Here is what it is supposed to look like---if those are the numbers from the injector mfg. The 0 row numbers are used all the way across the chart because you have a boost referenced regulator. Yes, your ve table will change.

[Lakegoat]

I can tell you that your engine likes 58 psi fuel pressure. You will pick up HP with the higher pressure. I did the same thing---tries 43 and then 58 and it gained a bunch with 58.

[Lakegoat]

Please fix your Power Enrichment---EQ Ratio (Gas) and EQ Ratio vs MAP. This makes your eq error and boost eq error graphs look way out of whack. Hard to tune ve without correct numbers.
You were at 9.48# of boost at one point in the log.

[jray1]

So if I go back up to 58psi fuel pressure then the injector flow rate would go to 46? Am I doing the math right there? What are you thinking the EQ ratio should be under MAP ? The 1.27 all the way across from 105-255? I also put in the deka 80lb injector data for the offset vs volts vs VAC . I will look to see if my data matches what you attached.

[jray1]

Good! Here is the OFFSET vs Volts vs VAC under fuel that I mentioned above. Here is what it is supposed to look like---if those are the numbers from the injector mfg. The 0 row numbers are used all the way across the chart because you have a boost referenced regulator. Yes, your ve table will change.

Here is the data in mine copied from the Deka 80 spreadsheet.

[eXo3901]

Here is the data in mine copied from the Deka 80 spreadsheet.

You posted "12309 - Injector Offset vs. Battery Voltage vs. MAP". Your offset is selected as "Vacuum" so you need to use data that corresponds with "12310 - Injector Offset vs. Battery Voltage vs. KPA VAC", which was the table Lakegoat posted above.

Also, If you are doubling your stoich value and halving your injector flow rate you also need to halve your IVT terms. "12560 - IVT Weighting Coefficient, AFR Term".

[jray1]

Sorry got in a hurry, trying to get kids to bed and do to many things at once. Grabbed the wrong tab.😂