mcbrew

Okay... I'm all about fuel economy. My xD is going to be ready to pick up tomorrow or Friday. I understand that lowering the car can yield better fuel economy at highway speeds. However, I do not want a car that bottoms out on bumps or has a harsh ride. I drove a Golf TDI for six years that had about 2" less ground clearance than a stock xD and would not want to go any lower.

I don't really care about the look. I don't feel one way or the other. The only reason I would get the lowered springs is for fuel economy and/or if the handling is improved without making it too bumpy.

So... my questions are:

1) Are people noticing an improvement in fuel economy with TRD springs?
2) How much do the TRD springs really lower the car? Scion says 1-1½ inches. What's the true ground clearance after installing TRD springs?

Thanks in advance for any opinions!

mcbrew

I tried to post this twice in the "suspension & handling" forum, but it keeps posting here. Is a moderator moving it? I would think a question about springs would go in the "suspension" section.

mcbrew

Well, according to the specs, the xD has 6.5" of ground clearance and my Golf had 5.1" of ground clearance. So, if I go with the TRD springs, I should have about the same ground clearance as my Golf (assuming the 1-1½" drop is correct). For the sake of fuel economy... and it's only $250... I think I'm going to go for it.

At today's gas prices ($1.70), a 2 MPG improvement would pay off in less than 100,000 miles, or four years at the rate I drive. If (okay, WHEN) gas goes back up, it'll pay off even sooner. Oh, and apparently my car will look better, too.

jsingh

i don't think that their would be a huge increase in mgp...and it won't be noticable.

mcbrew

Some people on the forum have reported a 2 MPG increase. MPG in the 30s is -low- for me... I'd love to be able to get it above 40 if possible. 1 or 2 MPG could make the difference.

its_ikon

you will not see an increase in fuel economy with lowering the car. you are not a race car, so trying to get better aero on a square car doesn't really work.

ChelsDS

You will not get mpg higher than maybe 38, even 38 is iffy. I consistently get 30mpg in my area and I am on NF210s but I don't drive like a granny. If you were looking for a car that got around 40mpg you should've gotten a Fit or something similar.

When I dropped my car I didn't see that big of a difference in mpg honestly. Though it has gone down slightly, maybe 1-2mpg, because I am on 18s now instead of the 16s.

TRDs don't drop that low honestly, but it is noticeable just barely though.


Oh if a mod was moving it, there would be a line under the first post about it being moved from <blank> subforum to <blank> submforum by <mod name>.

TRDxD

no real point in postin because eveyrone basically said it, but ill chip in my "no" as well ive lowerd mine and can say that theres no difference in mpg. its all about how you drive, and tire pressure. regular maintenance and weight also play a role. if youre carrying big loads all the time obviously there'll be a bit of a drop. just stick to driving speed limit, and not revving the sh** out of it.

its_ikon

on a side note, where did you read about getting better mileage from lowering the car? please post any and all links to this claim

TRDxD

most spring companies actually claim that lowering your car gives you better fuel efficiency due to less drag which it gives by lowering your center of gravity. its just a tactic to get you to further consider buying THEIR springs instead of others who dont make the same claim.

Technitarded

if you want a noticeable amount you'll have to go with a steeper drop. TRD springs will not change it enough, but even so with the steepest possible drop you'll only get maybe 1 mpg extra out of it if that. bang for buck, your better off getting your ECU reconfigured for economy but i'm fairly certain that that would void your warranty.

personally i always drive 6-10+ miles over the speed limit, i do not take my time accelerating and i still get acceptable fuel economy. i'm not trying to be a dick either, i just get bored driving 45 mph all the time and taking like 15 seconds to go from 0-30 like everyone else around where i live.

TRDxD

i have a lower drop, im on DF's, and theres no way that even on coilovers youd get as much as a full mpg more from just lowering. there's too much that holds us back (even a full tank hinders our liittle cars).

in all honesty, your speed isnt as important as your acceleration, but my point was dont drive like youre trying to get somewhere in 10 seconds..lol at higher speeds, for longer distances, you get better mileage (hence the fact that highway mpg is greater....). just as long as you sustain that speed for longer periods of time and dont have to constantly slow it down and pick it back up..

mcbrew

I hope to prove you wrong. I have gotten better MPG than the EPA numbers on every car I have owned. Using the new EPA numbers, my Golf was rated at 35/44. I NEVER got below 46 MPG unless I was towing a trailer. I usually got 50+ with regular diesel fuel. My best was 55 MPG (903 miles on one tank).

My fiancee has a 2000 Civic that is rated at 24/32 and I never get below 44 MPG. I have gotten as much as 39 MPG, but I haven't tried any serious hypermiling... plus it's an automatic.

It also has a lot to do with my commute. I have a ScanGauge, and it clearly shows that the average mileage increases with distance to a certain point. For instance, at 1 mile from my house, I was averaging about 25 MPG in the Golf. At 5 miles I was at 40 MPG. At 20 miles the average was up to 50 MPG. So, if you have a short commute, your mileage will suffer because the warm-up period is a significant amount of your drive. It wasn't too hard for me to get to work at 60+ MPG. Driving fast on the highway would kill that, though... and I have to drive up to PA almost every weekend, and that would bring my average way down. In town I could keep it up near 50 MPG unless there was a lot of stop and go.

Lowering a car reduces drag under the vehicle by reducing the amount of air that passes under. This is a fact. The only thing I am wondering about is how much of a difference it will make.

A 1-2 MPG increase is fantastic! +2 MPG would make it worthwhile.

I'll try. The search function on this forum is terrible.

Unfortunately, most cars (Scion included) don't have the tech following that VW TDIs have. If there is a question, someone will test it in a wind tunnel, inspect parts under an electron microscope, or send various fluids off to labs for testing. I'm not exaggerating... that's the way TDI people are. Around here it's mostly, "well, the manual says _____." It's just going to take some getting used to on my part.

its_ikon

sure, lowering a RACE specific car will reduce the amount of air that travels under it, but this is an economy car and if you are looking for fuel economy than you are not worried about going fast. since speed is not an issue, current speed limits in the united states will not yield an increase by lowering a square economy car 1". you are right about enthusiasts though, they truly care about doing the right thing to a car.

TRDxD

as i stated, its not much of a difference and i have calculated it based off my own driving. if this is true, no matter how you drive, your MPG shuold increase (even if its only slightly.) but there is just no way to get to 1mpg by simply lowering your car. but just because you lower your car and it decreases the drag coefficient, doesn't mean you can gain an easy 1mpg out of it, otherwise im sure cars would be engineered lower, to be more efficient for our "fuel conservation needs"

i have gotten 41 mpg driving so thats no myth...it was on highway, and if youre going to comment saying you dont believe me then by all means do it. i dont care lol.

i agree with you on the fact that distance can increase fuel efficiency, and this is also due in part to the fact that once your engine gets warmed up, then its actually up to its full potential. driving a mile isn't exactly enough to get your engine fully warmed up and operating smoothly, and if it is, then it just barely scrapes by, but then you turn the car off and youre back to square one lol.

mcbrew

Here's one reference to better MPGs from lowering:
Quote is by DeathMachine in this thread: https://www.scionlife.com/forums/viewtopic.php?t=235439
Also in that thread was some info about the Ford Flex. Apparently there was a 0.015 drag coefficient reduction by lowering the car by about an inch.

I don't understand why people are so quick to knock down an idea. If you don't know, just say you don't know... or nothing at all. Armchair science isn't very helpful.

TRDxD

dont know if youre refering to me, but i did state that i have DF"s and have noticed no such increase in mpg. if i can see proof of it then id like to see what it is that im doing wrong so i can increase my mpg. im not trying to knock it down without proof, im just trying to reason out WHY lowering my car didnt provide much results

ChelsDS

Unless you can support your MPG with actual numbers from tank ups, then I won't believe anyone till I see the numbers. Yes there are a few people who are higher than normal with their MPG amounts, but there is a LOT of fluctuations between owners on the numbers.

It could the gas in your area, it could be the amount of traffic, how you drive it (hypermiling ftl), rate of acceleration, etc. I know its definitely the stop'n'go traffic in my area that kills my mpg and also how I accelerate most of the time.

TRDxD

agreed. on top of the fact that, since our engines are all built to "such high standards" (not..) there is the possibility now that each engine is adjusted in less than equal standards. timing can be off, valve lash, machined surfaces can be different, etc. these also affect fuel consumption..

Technitarded

hence the determining factor of "if that much"

speed has nothing to do with mpg, its all rpms if you sustain 30 mph in 1st gear you will get terrible mileage, if you sustain 30 mph in second gear (some 3rd gears can take it as well) it will be much much better mpg. there you go, speed has nothing to do with mpg. high rpms = dumping more fuel into engine its that simple. and dont always knock aero, there is an artist that made a semi-truck concept that increased fuel economy by 63% without touching the engine.