load tuning problem

Dennis Makovskiy

Greenie N00B Member
Hello everyone! This might be a stupid question or maybe I'm not understanding something correctly but I'm having an issue load based tuning with cobb atr. So I'm running a bnr s3 with supporting mods and recently decided to try to load tune it. In the past I had good luck boost tuning and wanted to give load tuning a shot. Anyways all is good as far as the maf cal goes. And gears 2-5 I am able to successfully hit my load targets without any problems. I am also limiting load in 1-3 gears, this is working well except for the first gear. When going wot in first gear It wont hit my load targets its below targets but not too much, it looks like its pulling wdc. The other issue I'm having is it feels like from around 4500rpm and up its like having fuel cut issues, almost feels and sounds like I'm hitting redline the whole time. Also I noticed that in first gear the afr is really rich and I'm not sure if that's part of the problem. All the other gears are working just as they should without any problems. I will attach the datalog from that gear and maybe someone can point me in the right direction. On the base map I had it setup for spring pressure only and I didn't have this problem with first gear at all. If anyone can help or explain what I'm doing wrong I would really appreciate it.
 

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Dennis Makovskiy said:
When going wot in first gear It wont hit my load targets its below targets but not too much, it looks like its pulling wdc. The other issue I'm having is it feels like from around 4500rpm and up its like having fuel cut issues, almost feels and sounds like I'm hitting redline the whole time. Also I noticed that in first gear the afr is really rich and I'm not sure if that's part of the problem.
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Make sure you turn the traction control off when going WOT in the first 3 gears.
I target no more than 1.6 load in 1st because FWD FTW! I see you go well above 2, you will never even put that much torque to the ground.
Load 2 at 4000-ish RPM is about 470-ish Nm or 360-ish lb*ft of torque to the flywheel at 5-6 degrees of timing and a healthy engine, so multiply that through the gearing and try to picture how some street tires on non-prepped surface will withstand 4500+ lbft of torque on not even a half of a square foot of contact patch. Obviously they will not, so target less load there.

Also it matters quite a lot what EBCS you have and what did you put in the LEC tables. Up to a point it's not the torque that breaks tires lose, it's the torque ramp-up. So if the increase of torque is too sudden traction control will work like crazy.
 
I fixed the problem, turns out holding the traction control button when starting the car doesn't actually work. I ended up tapping into the swas plug under the steering column and installing an on/off switch. This way I wont constantly have the annoying light on my dash and when I wan wanna go wot or launch I can just flip the switch. Worked like a charm!
 
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