1/4 mile time and speed - JB4tech.com

Exarmy2010 · **1/4 mile time and speed -** 09-09-2021, 04:55 PM

I have a 440ix with jb4 and mhd, bef and running boost juice for my meth cpi dual bm7 injectors. I changed from the stock ******** to a catted AA ******** and my 1/4 mile time and speed didn't change. I checked the after market ******** and flashed the mhd, am I missing something?

Exarmy2010 · 09-10-2021, 04:15 AM

Just to clarify, my time and speed are the same before and after changing just the dp. Meth, jb4 and mhd bef have been on for awhile. Was expecting a better time and faster speed with an AA dp.

JBoe · 09-11-2021, 01:08 AM

Post logs so people can review and possibly help. A before and after set of logs would be best for explanation.

Exarmy2010 · 09-11-2021, 05:28 AM

First file is from 9/6 with the AA dp, second file from 6/22 is with the stock dp.

JBoe · 09-12-2021, 01:07 PM

There's timing hits in the new setup, that aren't in the old. The decrease in timing is likely what's taking away from the full gain of the DP Mod. You're running boost levels similar to what I'm used to and I had timing issues due to octane at those levels. That could be the underlying issue. Most at these levels are running 100% Meth (VP-M1) or E85.

I also don't like your WGDC vs FF readings. It looks like you have PID set high, but it's likely due to that you don't have the EGW Harness. I state that since all your bias settings are at 50/stock. If you do have the harness, you should trim PID down and use the bias to adjust your boost. That will trim down your range of deviation and allow FF to to work more effectively.

This may be a lot of information and may be more than you'll understand without reading up on the topic. It's also a very quick look at logs that aren't proper for tuning advice. I'm using the short 3rd gear pull area for review. There are several posts telling people how to properly do pulls for tuning. Yet, most still don't follow them. Those directions on proper tuning pulls aren't for your daily drive. That's what the FF does. The tuning pulls allow us to get the JB4 tuned so that FF has a chance to work properly for you in all other conditions. Tuning pulls should always be 2k-Redline in 3rd or 4th gear. The higher gear is preferred if there's room, but 3rd works.

Hope this helps... there's a lot of posts with similar information on them. One under the N54 is very helpful, just know that PWM is WGDC for us. JB4 Duty Bias FF Tuning Info - N54Tech.com - International Turbo Racing Discussion

Exarmy2010 · 09-13-2021, 07:30 PM

I have the ewg connection on my JB4, I dropped my PID down to 10 and did 2, 3rd gear pulls tonight. Hopefully I can fix my timing, so basically stage 1 tune isn't the same as what should be stage 2. I noticed you went stage 2 MHD and map 6, is that better?

Steve @ BMS/Fuel-It! · 09-14-2021, 11:18 AM

DP isn't going to do much...your settings were unchanged so it's not surprising you ran the same time. It's all about boost and timing. Adding mods is about allowing you to increase those and run more aggressive tuning, most mods don't add much power just by installing them, especially a stock DP to a catted after market on DP.

Exarmy2010 · 09-14-2021, 03:11 PM

I changed the bef setting from stock dp to aftermarket dp, shouldn't that have changed the tune? Otherwise what does the option do?

JBoe · 09-14-2021, 09:21 PM

Quote:

Originally Posted by Exarmy2010

I have the ewg connection on my JB4, I dropped my PID down to 10 and did 2, 3rd gear pulls tonight. Hopefully I can fix my timing, so basically stage 1 tune isn't the same as what should be stage 2. I noticed you went stage 2 MHD and map 6, is that better?

This is a really good log showing a strong setup. Timing looks great and adaptation looks great. Good job. You can trim down some of the low end throttle boost reductions by using the duty bias. I'd recommend starting at a setting of 45 for 1500-4k rpm. At 4500rpm I'd try 48. Relog and let's see how that looks. Leave everything else the same. Once you get about 1 psi, or less, under target you'll see those corrections go away. Some may not be felt, but it looks like most should be. Your pull should feel smooth and be as throttle closure free as possible. It's okay for boost to be controlled and slightly under target. We can always put in a little more additive to get your actual boost where you want it. Your trims are fine, but showing signs that fueling is going to become a concern going any higher. Just fyi...

As far as my tuning strategy... I wanted to try something different. I also found that the E30 tune from MHD had a more advanced timing curve. Dialing it in has made the car more powerful than ever before. I'm happy with the combo, but that doesn't mean it would work for you. Remember, I'm on E30, 100% Meth and using an Octane Booster. Some won't go as far as that as it does impact a daily driver routine. I have multiple vehicles, so no issues for me... even though I do daily drive this setup.

JBoe · 09-14-2021, 09:26 PM

Quote:

Originally Posted by Exarmy2010

I changed the bef setting from stock dp to aftermarket dp, shouldn't that have changed the tune? Otherwise what does the option do?

You may get some, but the tuning on that is mostly around controlling the earlier spool of the turbo. Again, it will get you some power... it's just not likely you'll feel it. Showing in drag runs will require you having a consistent pro-like driving method. Most of us will never see the full benefit of such, but it's still good to have the most we can... even if we can't maximize it. I like it as most times I'm not in a stop light situation it's from a roll or 20-30mph situation. It's in those situations that we can take advantage of all it's got. LOL!