2013 Boss 302 Whipple 2.9L Surging at moderate part throttle

[Lady L]

Hello everyone. Need some help/advise on this vehicle. Supercharger has been installed this past winter and have been tuned remotely (email tune from a big name tuner) and was also locally tuned. Email tune used a standard 2014 GT strategy while Local Dyno used the Boss strategy with Track Key enabled. Both tunes rans good idle, part throttle and WOT pulls clean all the way to rev limit @ 7500rpm. Making about 630whp/520torque @ 7200rpm. The only issue I have and have been trying to work it out myself this whole summer is when I stab the pedal at part throttle. The car will surge. To get rid of the surge is either I floor the pedal or back off and roll with the throttle. Both tuners told me that it is due to the bypass valve fluttering when it is near to closing which I believed that they are right. But what bugs me though is that both of the tuners said that it is normal for a PD blower to have that surge and that I have to change the way how I drive the vehicle. That takes away the fun of driving this car... So I decided to purchase HPT tuning interface so that I will check it myself plus I can also learn how all this tuning thing about my car. So for 4 months of browsing through the web of gathering ideas and applying it to my tune, I only made a miniscule progress of toning down this surge issue. Maybe I'm not doing it right or maybe the tuners were both right that I just need to learn to live with it Below is the vehicles info:

Vehicle info:
2013 Boss 302
Whipple 2.9L Gen4 w/ 3.75 pulley
stock throttle body
Injector supplied by whipple - 2014 GT500 injectors 52#
NGK 6510 Spark plug 0.028 gap
cat delete
Email tune - 2014 Mustang GT Strategy
Dyno tune - Revised Boss Strategy w/ Track Key enabled (lopey idle, launch control and aggressive engine braking are all functional with only a slight change)

Any help or advise is greatly appreciated. I'm all ears.


21-09-27 13-35-39.hplBoss Track Key_CatDel_Surging Issue.hpt

[SultanHassanMasTuning]

would need a datalog

log wheel torque error as well

personally i would be using a boost strategy

[Lady L]

would need a datalog

log wheel torque error as well

personally i would be using a boost strategy

Sultan, data log is attached at the very end of my first post together with the Boss strategy. If you can't open it, please let me know. Anyways, try this one again.

[SultanHassanMasTuning]

saw the log

shouldnt have that much error even at idle

something is off

[Lady L]

saw the log

shouldnt have that much error even at idle

something is off

I think the error at idle that you were seeing was because this log was taken when the Lopey Idle was active (track key enabled). This surging issue is present in both regular and track key enabled in Boss strategy. The same issue with the email tune using the GT strategy.

[Thatwhite5.0]

Do you have any logs with the non track key? The log is too messy because of the ghost cam. There's a messy blend between all mp.
I see issues in the torque and inverse tables. They're all exactly the same and aren't calculated right. Load is being miscaclculated and the car is running in optimal stability while accelerating. Torque eerrors are every where. Lower loads of the torque table values seem too high.
I see issues with spark advance too. Spark is all over the place even when torque errors aren't present.

[Lady L]

Do you have any logs with the non track key? The log is too messy because of the ghost cam. There's a messy blend between all mp.
I see issues in the torque and inverse tables. They're all exactly the same and aren't calculated right. Load is being miscaclculated and the car is running in optimal stability while accelerating. Torque eerrors are every where. Lower loads of the torque table values seem too high.
I see issues with spark advance too. Spark is all over the place even when torque errors aren't present.

Thatwhite .... Thanks for checking it out. Yes, I saw what you mean by torque and inverse torque values that were all the same. I was a bit confused when i saw that to coming from a person who haven't seen how a tune should look like. Stock Boss strategy do have differences in their torque tables. I tried to come up with my own torque table using the stock strategy and the % difference per table. I flashed it to the vehicle and as far as I remember, it didn't made a big difference. Maybe because there are some more PID's that needs to be recalculated on top of the revised torque/inverse tables. I just need some guidance on where to start with. I will do a log tomorrow using the normal key. I was planning to do that this weekend but weather wasn't cooperating. There is also a difference in the Load axis values for spark between BKT and MBT. It looks like they for got to renormalize those values on the MBT or they do it for a reason? See attached below.

Load Value Difference.PNG

[r2r]

Just went through this on a 2019 Dodge Challenger 6.4L + Whipple 2.9 and cam timing was primarily the issue causing the surging at light load (would jump from high vacuum to nearly atmosphere like a light switch. Also had to remap low voltage area for the throttle demand. It was a PITA. This being a Ford, surely this will be different but the cam timing is where I'd start

[Lady L]

Just went through this on a 2019 Dodge Challenger 6.4L + Whipple 2.9 and cam timing was primarily the issue causing the surging at light load (would jump from high vacuum to nearly atmosphere like a light switch. Also had to remap low voltage area for the throttle demand. It was a PITA. This being a Ford, surely this will be different but the cam timing is where I'd start

Yes, If you had looked at the log, almost every time it happens, the inferred vacuum value of the PID will drop close or lower than 3.5 psi. This value is also pretty close to the actual reading of my Aeroforce Boost/vacuum gauge values. I did remap my Torque Driver Demand and it help smooth out a little bit.

I know, I'm already loosing hair on these which I don't have to begin with

[r2r]

@Lady L

Haha ok that's good. IMO Dodge NA forced induction has been more challenging of all of the domestic brands. All nuances I guess.

[Lady L]

Update:

Today I did a couple changes/test on the tune. Below are the results.

1. Did throttle body tuning using the method I read around this forum. Used Throttle angle error and applied it to Predicted Throttle Angle, then did the Effective Area using the HPT calculator. I did like 3 runs while doing adjustments every time. Results shown in the log and by feel were minimal if there were any. Same amount of surging still present.

2. Used a Driver Demand from one of the post here with a lesser torque values and smoother slope going up top max torque value. Vehicles pulls smoother during part and WOT. Surging is the same when stabbing the pedal at part throttle.

3. With the help from Murphie (forum member), adjusted Speed Density>Quadratic Term as per instruction. No significant positive result I can feel and as shown in the log.

4. Smoothen out the original Driver Demand table. No go.

5. Found some article regarding Pedal Pos WOT Start value to give a lower value for boosted application. Changed value from 400 to 200. And then ..... walaaaahhhhhh.... 99% of surging gone. That 1% maybe due to the vehicle now drives soo aggressively. At a tap of my foot, it just shoots out. The Boss 302 from stock drives aggressively to begin with when using the Track key. This one now is like 5X more without surging (almost). I just said ...wwwoooowwwww!!!!

I don't know if this is the right fix but if somebody can chime in on why adjusting this PID took almost all of the surging? Is there any ramifications for doing it this way? Will I blow up my engine (no knock recorded during part/WOT throttle. I checked the IPC Torque Wheel Error and saw some huge numbers up to 1700. My Wheel TRQ Error Max was set to 225,000 by the tuner. With those error values that huge, will it hurt something on the vehicle or it will just trigger a fail safe and run to Limp Mode?

Lastly, Big Thanks to everybody for pitching in and especially to ThatWhite and Murphie for reaching out!!!!

[Thatwhite5.0]

The IPC torque error pid is a counter, not actual torque errors. Once those errors reach 225k, your car will go into limp mode and would just need to be restarted. I won't have my laptop until Tuesday to review the file and log to help clear out the errors.
Lowering wot start gives the pedal a light switch, on/off, feel. Will cause drivability issues going wot when driving normal. Usually highway speeds pulling up a hill or just needing to accelerate, car will go in to OP, torque errors and a very aggressive jerk. It's more than a surge.

[Lady L]

The IPC torque error pid is a counter, not actual torque errors. Once those errors reach 225k, your car will go into limp mode and would just need to be restarted. I won't have my laptop until Tuesday to review the file and log to help clear out the errors.
Lowering wot start gives the pedal a light switch, on/off, feel. Will cause drivability issues going wot when driving normal. Usually highway speeds pulling up a hill or just needing to accelerate, car will go in to OP, torque errors and a very aggressive jerk. It's more than a surge.

Ohh... I didn't know that IPC Torque Error PID are just counters. I thought they were calculated torque errors as what the units are showing when making a histogram. Learned something new everyday. May it be a counter or actual errors, is it an accumulated count per event then resets when that certain event ends e.g. , throttle change from accel to decel? Or is it the total accumulated count from key ON until key OFF during the whole drive time? Although it's too early to say for I haven't spent a lot of seat time yet on this revised tune but I like the way how it drives right now. From driving normal to going WOT is still the same as before. Aggressive take off when gunning the throttle (not WOT) with none to slight surge. The only negative difference were the IPC Torque Error values which are double the amount of what I used to have when the car was still surging. Maybe the numbers were small before because when the car surges, I just let off the throttle and then just roll with it. But now when I do the same moderate acceleration, even with the presence of IPC errors, I was still holding on the throttle because there is no surge. This could result to higher error numbers. Just my wild guess.

I like the way how the car behaves right now and I know that a lot of people here who's got a real deep knowledge tuning this cars would not agree that it's not the correct way. It is just a band aid. I myself believed that there should be a proper way of tuning out this surge and will keep on searching for that. I'm all open to everybody's opinion.