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ssullivan · 08-23-2020, 10:05 PM

Hello fellow TDI owners,

Curious what your practices are with regards to acceleration and shift points, and how it has impacted reliability. I understand that conventional wisdom is to imagine eggshells under the pedal. I believe with a stock diesel things are different, these have peak efficiency per bshp at relatively high load (see link). Just looking at the chart, you would want to get boost to around 7 bar, I assume 60-80% throttle, continue to accelerate to ~10bar, shifting maybe 1800rpm. I have a few concerns with doing this in my car, mainly ruining the bearings (lugging). This is also fairly rapid acceleration so discipline would be required to not dump that acceleration into the brakes.

I used to shift around 3000rpm based on something I read on another forum. Recently switched to 2500rpm. The deeper sound makes me more worried about lugging but I do not actually think it is. I have read some old threads, sounds like many people are shifting below 2000rpm. My question is, how long have you been doing this? What are your acceleration patterns? Have you had any major maintenance issues?

08-23-2020, 10:05 PM	#1 (permalink)
ssullivan EcoModding Lurker Join Date: Jan 2020 Location: Reno, NV Posts: 23 Jetta - '01 Volkswagen Jetta TDI Thanks: 5 Thanked 4 Times in 3 Posts	Shifting VW TDIs below 2000RPM? Hello fellow TDI owners, Curious what your practices are with regards to acceleration and shift points, and how it has impacted reliability. I understand that conventional wisdom is to imagine eggshells under the pedal. I believe with a stock diesel things are different, these have peak efficiency per bshp at relatively high load (see link). Just looking at the chart, you would want to get boost to around 7 bar, I assume 60-80% throttle, continue to accelerate to ~10bar, shifting maybe 1800rpm. I have a few concerns with doing this in my car, mainly ruining the bearings (lugging). This is also fairly rapid acceleration so discipline would be required to not dump that acceleration into the brakes. I used to shift around 3000rpm based on something I read on another forum. Recently switched to 2500rpm. The deeper sound makes me more worried about lugging but I do not actually think it is. I have read some old threads, sounds like many people are shifting below 2000rpm. My question is, how long have you been doing this? What are your acceleration patterns? Have you had any major maintenance issues?