revangel

So, I got sick and tired of the f*ked up looking scratches on my stock rims, heck I can't park right so I decided to pick these rims up:

http://[IMG]http://www.mccl.com.tw/s....jpg[/IMG]

I have Yokohama EVS100 Z Rated 215/50/17 tires which look really cool IMO.

Now, my gas consumption has suffered. I used to be able to pull around 340miles before my gas light turns on. Now, I'm under 300miles. WTF?!

I have NAVI, and I used it a couple of times since and the system is putting my car WAY OFF the marker.

Worse---I believe I have lost power. Acceleration is *very* slow and is not the way it used to. Shifting to higher gears (between 3/4 to 4/5) noticeable latency as well.

I recently (about a month and a half ago) had the major Schedule D (or E) done. So I'm really stumped.

Let me know what you guys think.

thanks,
--re

2001 Acura CL TypeS (Silver)

mclarenf3387

Unless they are light-weight rims, performance will suffer. Rims are heavier and harder to get rolling, hence loss of performance. Although, it shouldn't be like you turned off the power.

juniorbean

iTrader: (5)

How heavy is that rim/tire setup compared to stock? The odds are it weighs more which will make you lose some power.

Zippee

Sounds like something is dragging, have you looked to see if there is tire rub due to wrong offset?

If it was tire size, power would go up with mileage going down or vice versa depending on if they were too big or too small..

juniorbean

iTrader: (5)

That could be the other thing... what's the offset on the rims you bought??

Tire size seems right as that's the stock tire size if I remember correctly... so either they're really heavy or something's wrong with them....

Nashua_Night_Hawk

how about a another busted IMRC!

jimcol711

if the overall diameter of your new rims and tires is even the SLIGHTEST bit different, over the course of a tank of gas, it can have an impact on your mileage. here is a theoretic example:

your stock tires are 800 RPM (revolutions per mile)

your new tires are 780 RPM (15-20 revs per mile is not an uncommon discrepancy among tires from different brands that are called out as the SAME SIZE)

so now your car is going a mile in 780 revs but your odometer and speedometer dont understand this so they still anticipate and calculate for 800 RPM. so now for every mile that your ODOMETER says you go, you are actually going 1.026 miles.

over the course of 300 miles, that is actually an extra 7.8 miles that your car traveled but that your odometer does not register at all.

this also occurs the opposite way if your new tires have a SMALLER diameter and cause the # of RPM to do UP. your cars mileage will rack up too fast....on a serious note, this also causes your warranty to be over sooner than it should because over the course of 50,000 miles that descrepancy i mentioned above would cause a 1,300 mile descrepancy in your odometer!!! meaning that when your odometer hits 50,000 miles, you actually only have 48,700 miles, but you are shit out of luck. this doesnt take into account that over time and tire wear, the tires shrink ever so slightly as the tread wears down so in reality, this may be closer to 1,500 miles or 1,750 miles that come off your warranty that you get screwed out of.


bottom line is that matching RPM when buying tires is VERY important to keep the car performing the same way, getting the same gas mileage, having an accurate speedo, and having an accurate ODO.

just remember:

JUST BECAUSE 2 TIRES ARE THE SAME SIZE ON PAPER DOES NOT MEAN THEY TRUELY ARE THE SAME EXACT SIZE.

pimpscls

i think something may be rubbing, b/c 17 inch rims should not mess up performance? Also maybe your not used to the hotter weather during this time, our cl's suffer in hotter weather?

Pure Adrenaline

iTrader: (2)

So many people think wheels are just a simple bolt-on/bolt-off thing. They don't know that crucial factory development was behind the reason for choosing the size of the stock wheel.

That's why if you're going to get wheels and tires, you have to do just as much research as if you were doing any other mods. It's not just 5 lugs off and back on.

I'm willing to bet that the wheels are much heavier than the stock wheels, and the overall diameter is a bit off. That would account for the inaccurate reading on the navigation system. Get it recalibrated then recalibrate the navi system.

rondog

iTrader: (1)

340 miles! I'm lucky to break 200 miles a tank.

Nashua_Night_Hawk

first let us find some facts. What is the weight of the wheel? tires? what are the specs? offset, rim size, Revolution per Miles... etc...

Pure Adrenaline

iTrader: (2)

Hey, Nashua, any update on the SR headers?

Nashua_Night_Hawk

I know the following... the new 6-speed version is being prototyped. If the testing shows less than certain percentage of problems per 100 units... we will release the headers for shippments.

In a nut shell what we are doing is 100% full design-test-production cycle. Everything is redesigned from scratch.


This may explain the long silent time.


Nashua

GINge!

Not to mention the effect steering and suspension heavier rims have. Do you find cornering harder?

dfreder371

Rondog: If you are getting only 200 miles per tank, something is seriously wrong. That, or you live in New Delhi. Better get that checked out. You should be around 300, assuming you have a 17 gallon tank.

And revangle, 340 vs. 300 is almost a 12% drop (11.76%). Something is clearly not correct here. Low tire inflation could do this. Check your inflation with at least three different gauges.

pimpscls

^^ Umm i get about 120-200 miles to a tank with 91 octane, but lets just say i dont drive slow

revangel

Wow! This is why I am a proud CL owner. You guys rock! Thanks for the response everyone, I will do my best to address each issue.

Here's a background for you, my 'stock' tires were getting worn and I needed to get them replaced. I replaced them with the Yokohamas with stock rims and all appears to running 'normal.' I 'swapped' out the rims with the one I bought and that's how I got to this point.

Judging from what most of you have responded it appears to be the rim itself may have 'weight' or 'offset' issues. Can this be fixed? Can a local tire pro adjust it?

Answering one of the questions, yes, 'cornering' almost feels like I'm 'sliding' (somewhat). In addition, I have noticed that at 32 psi, my tires look pretty flat. So I pumped it up to 40 psi (max at 44 psi per disclaimer on tire wall) and I noticed 'some' degree of progress.

Thanks again guys.

--re

NiteQwill

7-11mpg? I don't think so. Even flooring it at every light doesn't produce that type of mileage. I thought you said you were a master driver?

Smitty

pimpscls is just a master post whore and his days here on A-CL are coming to end quickly.

Smitty

no it can not be adjusted... I would research the wheels you bought and report back with the weight and offset.

Smitty

dano80g

This is only true if you had the speedo calibrated to the new smaller diameter tires or you're measuring didtance traveled by some other means other than the odometer.

The odometer works on the function of rpm of the transmission output shaft and can't adjust itself to different tire revs/mile.

The power loss is probably a combination of heavier wheel/tire combo, more tread depth (rolling resistance), tire construction, larger diameter (full tread 3/8" vs bald tires, 3/4" increase in diameter.) and tire psi.

Sly Raskal

iTrader: (1)

man i drive my 6spd pretty aggressive and i still average about 275-300 a tank, there's no way you're only getting 120 -200 miles a tank unless your driving around the whole time staying at above 5k RPM

the worst i've ever done is maybe 250 but even that only happened once.

Smitty

typeR

240-270 17 gal tank yes but you fill it about 15 gals.

revangel

Ok guys, did my homework and here's what I got:

Size: 17x7
Weight: 18.5 lbs
PCD: 114.3(mm) x 5
Offset: 40 mm

I don't have the numbers for the stock rim sorry.

thanks in advance,
--re

mclarenf3387

Im not sure but I believe a 40 offset is too low. The weight doesn't seem to be too heavy though. Wonder why your down on power?

EricL

1. The change in loaded radius (AKA revs/mile) would be minimal since the worn tires you would be replacing would be worn. (I replaced the stock tires when they were new since I hated them so much, but I am assuming that yours were worn down pretty well.) The stock tires are considered worn at 10/32”. That’s pretty close to 1/3 of an inch, and that is only the radius. The stock MXM4s have a rev/mile of 819, and the EV100s have a rev/mile of 815. The ratio is 819/815 = 1.004 IOW, they are within a half of a percent of the stock 215/50-17s. This is based on the data on Tire Rack’s website. The difference between a new OEM (MXM4) tire and a worn MXM4 tire is: 25.5 / (25.5 – (10/32) * 2) = 1.025. This difference is greater than 2%. So, if anything, the new tires would only give you a more accurate speed reading.


2. I changed my tires to 235/45-17 Toyo T1S Proxies, and the speedo difference is about 0.5- to 1.0-percent depending on various factors. I have had NO problem with navigation. The NAVI constantly checks the wheel speed sensors against the satellite data, and updates internal correction tables to TRY and insure that the navigation data will be accurate when you lose one or more satellites. You need to have 1) the NAVI checked out and/or 2) have someone verify that the tires that were installed on the tire are not duds – however unlikely that sounds to me.


3. You gas mileage WILL be dramatically affected by TWO factors: Wheel weight and size; and tire rolling resistance. The original MXM4 tires are very efficient and the difference in rolling resistance will be realized in proportion to certain driving patterns. IOW, if you drive on the freeway and don’t accelerate too hard, the tires will have a LARGE impact on your mileage. If you accelerate hard, and drive around town in stop-and-go traffic, the tires will have a minimal impact on gas mileage. OTOH, the weight of the wheels will have a PROFOUND impact on your acceleration and gas mileage. If you selected some heavy cast wheels, you will find the car will be a good deal slower and will eat up more gas under MOST conditions.


4. Finally, it is not uncommon to have a random event or failure occur that coincides with some “change.” You might want to check your intake manifold actuator for proper operation *and* you might want to see if the rest of the car’s components are clean and working properly. Has anyone changed or looked at your air filter? Are you sure that they haven’t changed the gas fractions for summer or for some other reason?

IMO, check the wheel weights and your air filter. You should be able to get the wheel weights from your vendor, you should be able to look at your air filter, and you should be able to see if your IRMC is actuating at around 4000 RPM.


BTW, I just looked at the post with your wheel weights and you should be doing BETER than stock. Stock 2001 CLS 17x7 wheels weight about 25- to 26-lbs. There are construction issues that WILL alter the rotational inertia of wheels with identical weights, etc, but the stock wheels are REALLY heavy on the outside -- this should eliminate the weight issue on your new wheels. IMO, the offset is way too low, but if you don't mind your wheels sticking out, have at it. You might want to check the tires for rubbing -- that would screw up a lot of stuff. Also, check the other issues I mentioned (air filter, IRMC, gas formulation change, etc). YOU WILL LOSE gas mileage with the stickier compound used by the Yokos

http://www.acura-cl.com/forums/showt...highlight=IRMC

wakeboardfusion

i have a 99 3.0 and i usually get 180 miles on a tank

Hobo

mrsteve it looks as though our numbers are growing

pimpscls

sorry to hijack, but why would i make that up, are you guys fucking serious. First of all, my driving is purely city anf full of hills with nice turns , And i tend to drive very fast on these turns. But ne ways i dont want to argue, thats what i get, maybe there is soemthing wrong with my car? B/c every 6-7 days i fill the tank up, and i only go to school and couple of places here and there, i know its not more then 220-240 miles a week

Hobo

um.. 120 - 200 is a lot different than 220-240... make up your mind

Joe5.0

Most likely the rims did not cause the mpg or power loss. They are lighter than stock, and the tires would never cause that dramatic of a drop.

Check your air filter and actuator. Thats my opinion.

EricL

Be careful about "never" (I'm not saying that your wrong; I'm only pointing out that it is very hard to judge driving conditions and what effect tires can have on "some" folks.)

I lost about 2 MPG with the switch to the Toyos. That is predicated on mixed city + freeway. The loss was almost 5-6% on freeway only driving.

When I was driving like grandma in town, I originally got around 20 MPG (with 'mixed' traffic). It dropped 2 MPG with the 235/45-17 Toyos and no other changes (they are a lot stickier and I still had the stock/heavy wheels). I was happy to make the trade for the better acceleration no pig squeal, and much better handling.

Every person is going to have a different result with the tire upgrades, but don't completely dismiss the rolling resistance issue – it can be an large issue at certain speeds when people don’t accelerate hard.

I believe Tire Rack says you will lose 2-3% with max performance tires, and is probably in range for "mixed" driving (hills, freeway, city traffic, etc).

pimpscls

hobo i was right the first time just filled the gas tonight, and what did it say 191 miles, does that seem odd? what do you guys think is wrong?

VXCL

this is the only time im glad i have a 4 banger. 32 mpg is sweet. i dont see why ur milage is so diff now from just your rims. they are pretty light for 17s. a 40mm offset should be no prob either for a 17x7. strange things happen. maybe something else is wrong ad becuase in your mind the only new thing you got was rims your quick to blame them.

Joe5.0

Well, I only know what I experience. Here's a quick shot of the stuff I've done:

On my Taurus I put on 17x7.5 chrome wheels with 235/45/17 Kuhmo's. The wheel/tire combo was about 12lbs heavier than stock and the stock tires were high treadwear 215/60/16's. It did cost me about 2 tenths & 1-2mph in the 1/4, but no matter what I always got 23-24mpg, no matter what the weather or what wheels I had on.

My Mustang is even more radical. The stock wheels are 16x7.5 & had 245/50/16's. The wheel/tire combo weighs 38.5 lbs, and I replaced them with 17's that weigh 51lbs a piece. The tires are 275/40/17 & 315/35/17. I lost ZERO mpg, the speedo was actually more accurate than the stock wheels (due to rear gears and the tires being slightly taller), but at the track I did lose about 1-1.5mph due to the increased weight & rolling resistance.

So, if neither of my cars lost any mpg with going with a much more radical tire/wheel combo, how could a lighter wheel and slightly more grippy tire cause him to lose 40 miles per tank, or about 2.5mpg. My best guess is that the navi/trip odometer is acting screwy and giving a false mileage reading or there is some engine problem causing the car to run too rich.

VXCL

sorry to hijak ur post but since there are so many knowledgable peeps in here i have a ?.

im waiting on some 17 volks to come from japan and i want to get bridgestone potenza re750s. what size would you buy?

my oem is 16
205/55 michlins of course
89H SL
831 revs/mile
25" diameter

my two choices are 17
215/45
87W SL
847 r/m
24.6 diameter

or
225/45
91W SL
833 r/m
25" diameter

now i have a 4 banger so weight is very important to me thats why i got some 16lb forged volks and the rays light performance lug nuts. how much more weight u think the 225/45 will add? it seems the 225 is the better match. i kinda feel 225 is a little big for my 1st gen's small body. what would you guys buy?

oonowindoo

most of the aftermarket 17" should be lighter than stock 17". maybe your just too paranoid. You will not get exact 340 miles on every tank. when i had my CLS, i would be very happy if i can get anything over 260miles per tank. and i had 18" rims and i had navi too. It was off.. but not by far.

it should not affect your performance by THAT much as you described. you sounded like you got some 20" chromes.

40 offset is a little low but it should be ok because the rims width is 7.

IF you are really getting 300 miles per tank. Just be happy with it. Most of the ppl could barely pass 260 miles per tank.

oonowindoo

_______________________________________
Simple solution:
If you want wider tire look and more traction. go with 225 45 17
If you want Everything to be as light as possible go with 215 or even 205.
But to me 225 is pretty much the same as 215. i am pretty sure you cant feel the difference unless your butt is SUPER sensitive =)

Nashua_Night_Hawk

It seems the tires are wheels are not the cause of your MPG problem.

From my experience, in addition to the expected 2MPG loss due UHP tires...

Note: My Overall Summer MPG is 22-23 MPG and Winter is around 17-18 MPG. Only on long trips (300+miles) I get 27+ MPG

I found out:
1) Bad Gas will kill MPG... once I pumped cheap shitty gas and had like 120 Miles for a full tank!
2) Winter Gas... up to 4-5 MPG loss.
3) Fuel Injector cleaner ($2-$3) will help improve MPG noticeably!
4) Clean your engine air filter if it is a K&N or replace the paper one.
5) If IMRC is broken, then fix it!

Nashua