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Old 11-18-2021, 10:29 PM   #8 (permalink)
Blue Angel
EcoModding Apprentice
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Join Date: Feb 2013
Location: Ottawa, ON, Canada
Posts: 190

Previous Car - '12 Chevrolet Cruze Eco MT
Team Chevy
90 day: 44.29 mpg (US)

535d XDrive - '16 BMW 535d M-Sport
Thanks: 17
Thanked 59 Times in 38 Posts
I believe modern turbodiesels have artificially sluggish response purely for emissions reasons. They only add fuel at a rate slow enough for the turbocharger to completely keep up, since running even slightly rich results in huge increases in particulates and soot.

This was evident when I drove truck for a lumber yard in my younger years. The old '90 (I think) International 466 flatbed 5-ton was a joy to drive, and the throttle response was very good - it was like the tach was simply attached to the throttle pedal with a cable. You could put that engine anywhere you wanted with speed and precision, making it an absolute pleasure to rev-match. (For those not aware, you only use the clutch to get it moving in the lowest gear, and it's all clutchless shifting from there on out).

A newer International 466 they leased, a '96 I think, had an electronically controlled fuel delivery system and felt completely disconnected compared to the older truck. It took me a long time to adjust to driving it, and even though it had air conditioning (and an advertisedpower increase) I still preferred driving the old '90.

Having said all that, the engine in my 335d is quite responsive. It's sitting in front of an automatic transmission, so it's pretty much blasphemy to speak about throttle response... if it was a manual, OK.

EDIT: Forgot to mention that the older trucks would spew black smoke on every shift as the turbo caught up to the fuel being dumped into the engine by the mechanically actuated fuel pump. The newer electronic engines had no such black smoke between shifts, but they seemed to take FOREVER to spool back up and make power.
2016 BMW 535d
4100lb XDrive Eco-Yacht

Last edited by Blue Angel; 11-18-2021 at 10:39 PM..
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