@xtrentonsmithx_177564 If this the Veloster you have a thread about with some kind of knock why are you even still looking at it ? Go find something that does not have you on the web asking questions.
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If you remove the turbo your mileage will probably worsen, and other issues are not unlikely.
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Although every vehicle sold in this country has a “theoretical” fuel economy rating, the fact remains that this is not set in stone. How you drive and maintain your car will greatly affect the fuel economy. If you keep it maintained, and avoid driving aggressively, you can achieve decent fuel economy, even from a so-so car.
For example, keeping your tires properly inflated and allowing the car to accelerate slowly through all the gears will improve the fuel economy. So will rolling down the windows and turning off the A/C, and turning off the engine if you have to wait for more than two minutes (e.g. if you have to wait for a train to pass).
I have never gotten less than the rated fuel economy out of any car, except when it had engine/mechanical problems, and when ultimately repaired, the fuel economy improved.
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I am always astounded by the number of people who don’t do this. The typical driver seems to keep his/her vehicle in gear, with a foot on the brake pedal, rather than simply putting the vehicle into Park and shutting off the engine. Very wasteful!
If you want a steak for dinner, can you buy an eggplant and pretend it’s a steak? Sure. Will it work? Well, no.
With a traditional automatic transmission where there is loss from the torque converter certainly! I think using the shift lever to keep the transmission in a lower gear for a little bit longer than it normally would while accelerating can help reduce torque converter loss and improve over all economy. But doing this also increases engine inefficiency by having it run faster, so it’s a trade off. I have a car with a large gear ratio difference between 1st and 2nd gear, and I’ve been holding it in 1st during acceleration up to around 2800 RPM instead of the normal 2400 or so when it would normally shift and I think it helps a bit. I also increase the throttle a bit as the engine speed increases, since torque converter loss becomes less and less at higher engine RPM.
With a manual transmission there is no lost efficiency by using full throttle with a naturally aspirated gasoline engine. A gasoline engine doesn’t become less efficient at full throttle as long as the RPM is steady. Keeping it between 1500 and 2500 RPM and flooring it during acceleration should actually improve fuel economy a bit.
You are not really saving much fuel that way . Actually I doubt if you are saving any at all.
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I don’t know how to quote what someone said on this iPhone, but that last part of what you said…I’m not sure that’s correct. Fuel mileage is going to be somewhat inverse to rpm. Hence the high (low numerically) gear ratios cars get saddled with during a fuel crunch. Like 3.08 gears in a half ton truck…which are awful, btw.
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Automatic transmissions have universally had lockup torque convertors for over 25 years. The loss is only from a dead stop. Lockup occurs very quickly. Unlock occurs momentarily between shifts. This is all to reduce losses.
Not true, the more you open the throttle, the more acceleration you command and the more fuel you will use.
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I thought the idea behind 8 speed automatic transmissions was that the shifts would occur at lower RPM while still giving acceptable acceleration in normal driving therefore using less fuel . Have I completly got that wrong .
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+1
And, it is worth noting that Studebaker’s automatic transmission (co-developed with Borg-Warner) had a lockup torque converter going back to 1950!
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Nope! More gears means the engine can be kept at its most efficient point more of the time.
The current 10 speed automatic Mustang is quicker than its 6 speed manual stablemate in 0-60 and 1/4 mile tests AND gets higher MPG ratings! More speeds = more better
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That’s not why the fuel economy tests exist. They determine fuel economy in the same way for all vehicles tested. This allows a buyer to compare different cars to see which one gets better fuel economy.
Allows the buyer to see which ones get better theoretical fuel economy! By that, I mean some seem to do better at the mpg testing than they do in real world driving, for whatever reason. Seems particularly true for some turbo engines and engines with cylinder deactivation in truck, for whatever reason. There must be some part of the test that no one ever really (or rarely) encounters out in the wild, like a steady cruise at 50 mph or…something.
Most cars now have an EPA rating but also on the sticker it says you can expect to get between two numbers for city and highway driving. Our 2019 CRV gets 31mpg regularly on the same mixed loop that the 2007 CRV would get 22mpg. Combination of the CVT and 1.5 Turbo vs the naturally aspirated 2.4 Automatic in the 2007.
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How about hybrids? I heard that they start the test with the hybrid battery charged and end the EPA fuel economy test with the battery discharged. That’s quite unfair!
The city fuel economy for the manual transmission versions of cars seem to be too low compared to the automatic version. I think the test driver is shifting too late and letting the engine rev up too much. However this is probably an accurate test based on how most people drive a manual.
Automatic transmission torque converter lockup in all or most gears has been a more recent thing, more like the last 10 to 20 years. The traditional 4 speed automatics all lock up in the highest gear since the 90s or before but that’s only relevant for highway driving.
When an old 4 speed lets the engine go up to 2250 RPM in 1st gear with the input shaft at 2000 RPM at 15 MPH, and then it shifts in to 2nd with the engine dropping down to 2000 RPM with the input shaft at 1100 RPM it loses a lot! 2000 RPM going in and 1100 going out of the torque converter is a lot of loss!
Heard from where?
Not so much if the output torque is higher then the input.
Thus, torque converter.
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I don’t know that’s the case. Even if it is, folks seem to be getting as good or better than EPA estimates:
Browse On-the-Road Fuel Economy Data
I think you should quote or read all of what I wrote and not pick out a single sentence here and there and then compare apples to oranges to show how it is wrong.
I don’t have a source for the EPA hybrid vehicle unfair MPG test. It’s one of those things that someone who seemed to know what they were talking about said a while back. Perhaps there is some detailed government document somewhere that sets the standard for how the tests are done and possibly allows this loophole to exist?
edit: Also, it doesn’t necessarily mean that every manufacturer is using such a loophole on the test. More real world data should be studied. https://www.fuelly.com/ seems to be a good source. I assume that people who are more aware of fuel economy use that site so it tends to be biased toward people who drive to save gas. For example, the 2010 Prius gets 51 city 47 highway according to the EPA, but on Fuelly people are getting close to 44 MPG for that generation Prius.
I posted an opinion about what Thewonderful90s ( Formaly Invisible Snowman ) posted . I said I don’t think he knows what he is talking about . No name calling - no profanity - so I don’t understand why it was flagged and removed.
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