Yes, correct. Everybody wants smooth operation but beating their competitors and making the EPA happy wins the war!
I fully and completely disagree with you. First, my experience with engineers is that they are lazy. They donāt change anything they donāt have to and they do NOT listen to anyone outside the engineering department.
Second, they tune for performance, not economy. They only include things for economy that do not compromise performance. The reason is when someone takes a vehicle out for a test drive, they do not feel the fuel economy, they do feel the performance though.
Extensive testing by BMW found that shifting early and using more throttle maximizes fuel economy, but it makes a vehicle feel very sluggish.
When I drive a manual transmission, I shift early and use plenty of throttle and it works. My 2002 Saturn was rated 29/40. I got about 40 on road trips, but I averaged 37.85 mpg on a 50/50 mix of city/highway (I kept a spreadsheet). My 97 Nissan PU rated 20/25, I got about 24 on road trips (drove too fast), but got 25.5 when I worked it the big city and did mostly city driving.
A lot of the increase in city mileage was from timing red lights so I didnāt stop very often. That yielded an almost steady speed of around 40 mph which is really good for milege.
So have you met and spoken with any of these engineers that tune the powertrains for a major manufacturer? I have. I used to work for one of those manufacturers.
Yes, they want performance, everyone does, but when their boss (who is IN the engineering department, BTW) says our competitor gets 27 mpg composite on the the EPA schedule and WE get 26ā¦ the team gets to work to get that extra mpg and more because that shows in their annual raise just like it shows in their bossā annual raise.
Having worked in and with development groups that tune suspensions, engineers in these groups never want to STOP changing things. They will adjust damper and bushing tuning until the last minute of the production deadlines to get the car or truck as good as they possibly can. With electronic shocks, youāll hear the argument that it is ājust calibrationā so work may continue almost to start of production.
Of COURSE it does. Every carmaker knows this. The wider the throttle is open, the lower the pumping losses. That is why engines drop cylinders to improve economy. The tradeoff is performance for economy. BMW tends more to performance, Kia may trend more to economy.
Driving a manual, you have that control. Driving an automatic, the calibration engineers have that control.
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I think if that were true, thereād be no aftermarket tuners. Or āsport modeā for some of the newer transmissions.
Thereās a bit of a caveat there. IIRC the EPA estimates are done with things in their default mode (you start the car and go without adjusting drive modes/settings, etc.). Which is why things like auto start stop are on by default every time you start the car. As far as transmission programing/logic goes. If the car were to start in a āperformanceā or sport mode. Then itās possible that the short-shifting people are noticing wouldnāt happen, but the on-paper fuel economy would be slightly negatively affected. So in that respect they are giving the best they can give you within the confines they have to work within. On a side note my F-150 defaults to the ānormalā drive mode. But it also has Eco, Sport, Snow/Wet, and Tow/Haul settings for the transmission. Maybe they were able to meet the CAFE numbers without having to resort to having Eco mode as the default.
If the competitor that gets 27 mpg has only half the sales, and the engineering department tweeks their vehicle to get 27 mpg and one of the editors of a car magazine or internet influencer notices the drop in performance, sales will drop and you. can bet that the performance will be tuned back in, regardless of the gas mileage. SALES is the king here. Engineering will never override the sale department.
Yes, I have met the guy that was in charge of Fordās Modular engine system. He had a Billion dollar budget from Ford. He was a tweeker, but I never saw another engineer from Ford that dedicated. The other manufacturers we supplied cylinder heads to would send sales reps or purchasing reps to do what the engineers should have been doing.
BTW, that guy from Ford would show up in coveralls looking like a local farmer, go over to the repair area and get with my welder and they would pull a couple of heads off the line and start reshaping ports and combustion chambers and then off he would go with the modded heads for testing. You would never know to look at him that Ford trusted him with a Billion dollar budget.