[xboxgod]

Got my car back after 4 months in the shop. It's been a couple thousand miles so I slapped the JBD back on and went to the 1/8 mile track last Thursday. First run straight off the highway...


Now the rest of the runs were horrible (Mostly 8.9-9.1's). The problem is this:
Driving the car to the track at 60-70 mph allows the car to warm up, yet prevents heat soak. If I park the car for more than 5 minutes and then go run...Limp Mode. If I turn the JBD down to 80% (highest I can go to prevent limp mode), I get 81 mph trap speeds instead of 83. So I have to leave the car running through the lanes if I want to have the JBD above 80%, which I believe is causing heat soak and making it run bad. Thoughts?

*Note: My best run at the 1/4 mile track last year was straight off the highway after a 45 minute drive at 70 mph.


I then took the car to the dyno on Saturday. Here are the results from my October trip (stock) and my trip Saturday (JBD 100%). Sorry for the cutoff at the bottom. It says 270whp (JBD) and 235whp (Stock).


Now the problem here is that joe_planet had the Ecotune on his 335d and went to the same dyno. He put down 290rwhp and 450rwtq, 20ish more whp and 20ish more wtq. He ran at the same drag strip as me and never got better than an 8.8 sec time slip. So I don't know if the dyno is actually messed up or if the JBD just works when it wants to.

They guy at the shop looked up the humidity and temps from the October dyno and they were almost the same (2 degrees different). Plus, the machine corrects for that too anyway. Thoughts here? I am considering the Ecotune or Evolve tunes, but not sure if I will see any better results until I get the down pipe, intercooler, and meth. Thoughts here?

[Puerto Rican 335d]

I beleive the ECu has to adapt itself in time with the new programming thats my two cents or the JB might of gone bad , in that case call Terry Im sure he can get a fix . Also either you get Ecotune,evolve, JB or RENNtech it will be better than STOCK!!

[joe_planet]

Hang on a sec there! What I was trying to say is that I never got a time UNDER 8.8!
Most of my runs were in the 9.0 range. This is comparable to your JBD. The 8.8 run was a very early run in the night, so I think that corresponds to you getting a best run at the beginning and then getting some heat soak. I do remember when I ran my car at the track it was really hot, 90 degrees at least and relatively humid. I think the dyno is most likely correct. My car is gone though.. so I there's nothing else we can find out...

[TDIwyse]

The loading of your DPF can have an impact. As it loads more there's more pressure building and the EGT's go up for a given amount of fueling. The car (at least mine does) defuels to protect itself at high enough EGT's. Unless you are measuring the EGT's and DPF pressure drop (I can do this with the Bavarian Technic tool) you really don't know if its an apples to apples comparison. That's why I wouldn't trust ~10-15hp differences from one day to the next really showing much if any factual difference, unless you also had the DPF/EGT data from all cases to compare those variables.

I've seen ~20'ish hp and several tenths sec on the dragrstrip difference caused by the DPF and EGT impact. Also, after two fairly closely spaced runs on the dragstrip with the DPF in place I was seeing A LOT of passive regeneration going on which really raises EGT's and engine coolant temps...

[Hoooper]

definitely idling your car the whole time can cause heat soak and worse times. When I went I turned the car off and popped the hood, I had pretty consistent 8.3x 1/8th miles. I made sure to head back to the car a little bit early so that I could start it and let it run for a minute before the track. It probably ran for between 1 and 2 minutes before the pass and I did not get any limp mode. This is while running JBD 100%, I do definitely get limp modes if I dont let it run long enough

[xboxgod]

Originally Posted by Hoooper

definitely idling your car the whole time can cause heat soak and worse times. When I went I turned the car off and popped the hood, I had pretty consistent 8.3x 1/8th miles. I made sure to head back to the car a little bit early so that I could start it and let it run for a minute before the track. It probably ran for between 1 and 2 minutes before the pass and I did not get any limp mode. This is while running JBD 100%, I do definitely get limp modes if I dont let it run long enough

So did you start and stop the engine in the staging lanes and then leave it running once you got close?

[Hoooper]

Originally Posted by xboxgod

So did you start and stop the engine in the staging lanes and then leave it running once you got close?

the staging lanes at my track arent constantly moving, you park in a group up to around 15 cars long and the group doesnt move until the front cars start heading up to the line. I didnt start and stop while the line was moving but the engine was probably off for 30 minutes or so and then running for up to about 2 minutes before the run