Ecotec 1/4 Mile Times!

[Daytona]

Nice times. But if you go with bigger wheels up front you will effectively slow down your gear ration since it's FWD. The smaller the diameter of your active axle wheels (in this case the fronts), the higher the effective gearing becomes. Don't know off-hand what the gear ratio is for the Alero but you will notice a significant difference by just changing the wheel size (all else remaining equal, including wheel/tire weight). You should also pay close attention to the weight of the new wheels & tires relative to what came stock on the car and against what's on there now. Lighter wheel/tire combos allow for less spinning resistance as it takes more power to rotate a heavier combo.

Best advice if you're looking for best ET is to go with smaller & lighter wheel/tire combos.

Best advice if you're just going for looks = do what you think looks best on your car.

[b-spot]

LOL Daytona.

When you put bigger rims on you put on lower profile tires. Any good performance shop won't sell you anything that is more than 3% out of stock overall diameter.

[Oldsman]

well when i bought my tires, they went to give me crap about those aren't correct size of tires. but i told him i know, your computer is telling 215/60R15 but i want 225/50R15. But that will change your..........I want that size, end of discussion. That is how it kinda went..........LOL

The inch shorter tires have helped out of hole. i did loss about a mph on the top end but the price you pay. To give you an idea on the gear ratio. factory is 3.42 on the auto 2.4 after the new tires i am at 3.59

[Daytona]

B - Any "GOOD" shop, maybe, but half the time the shops just sell you whatever they can sell you if you don't know what exactly you want or need. And you CAN go over 3% difference very easily if you aren't careful about what you're doing. Best thing is to buy the rims and tires together to make sure you aren't throwing money out the window on a combo that won't fit under the car.

Plus, larger rims + lower profile tires can still add up to more weight than stock rims and regular profile tires.


And thnaks, Olds, for the gearing example.

[b-spot]

Originally posted by Oldsman@Jun 3 2004, 12:16 PM
well when i bought my tires, they went to give me crap about those aren't correct size of tires. but i told him i know, your computer is telling 215/60R15 but i want 225/50R15. But that will change your..........I want that size, end of discussion. That is how it kinda went..........LOL

The inch shorter tires have helped out of hole. i did loss about a mph on the top end but the price you pay. To give you an idea on the gear ratio. factory is 3.42 on the auto 2.4 after the new tires i am at 3.59

I realize this oldsman, but there are a couple reasons I would NEVER do this.

1) BIGGER wheel gap? Dear god know. Its big enough already

2) You are killing your gas mileage at highway speeds

Not worth it. Its a pretty cheese ball way to try get more accel.

How far above/below sea level were you?

[b-spot]

Originally posted by Daytona@Jun 3 2004, 12:26 PM
half the time the shops just sell you whatever they can sell you if you don't know what exactly you want or need. And you CAN go over 3% difference

Actually you will get a hassle from any shop if you try order a rim/tire combo that is out of stock OD specs. There are liability issues involved if anything goes wrong from f*in around with this stuff.

And yah, you can go outside stock specs like oldsman mentioned, but if you go bigger you are just gonna slow yourself down, and going smaller, see above.

The engineers that design your car do have some idea of what they are doing when they make the gear ratios the way they do.

[jturkey69]

i say leave the way your car is for drag duty, if you want better numbers, just work on your launch technique...this was your first time right??...just find that sweet spot between bog and total wheelspin

[Oldsman]

Originally posted by b-spot+Jun 3 2004, 12:30 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (b-spot @ Jun 3 2004, 12:30 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-Oldsman@Jun 3 2004, 12:16 PM
well when i bought my tires, they went to give me crap about those aren't correct size of tires. but i told him i know, your computer is telling 215/60R15 but i want 225/50R15. But that will change your..........I want that size, end of discussion. That is how it kinda went..........LOL

The inch shorter tires have helped out of hole. i did loss about a mph on the top end but the price you pay. To give you an idea on the gear ratio. factory is 3.42 on the auto 2.4 after the new tires i am at 3.59

I realize this oldsman, but there are a couple reasons I would NEVER do this.

1) BIGGER wheel gap? Dear god know. Its big enough already

2) You are killing your gas mileage at highway speeds

Not worth it. Its a pretty cheese ball way to try get more accel. [/b][/quote]
1. they make lowering springs. but if you going to do smaller diameter tires then you really aren't about looks to begin with.

2. killing gas mileage??????..............hummmmmmm. I get 31-32 on the highway. The gear ratio isn't changing enough to kill gas mileage. now if you went to like 4.10 then yes.

the only thing is your speedo does not read accurate anymore.


Do what you want. and see how it all works out for ya.

[MikeSS]

I got 17' rims with 45 series tires cause they keep the same rolling ratio. I know the are heavier and that is why I'll put on my stock tires in the back. My stock rims are light, but the tires are so poop I was doing a big chirp between 1st and 2nd and could even feel a bit of slip from 2nd to 3rd. The new tires probably will slow me down on wieght, but oh well. I am am going next saturday again so I'll see what happens.

[MikeSS]

Originally posted by jturkey69@Jun 3 2004, 03:44 PM
i say leave the way your car is for drag duty, if you want better numbers, just work on your launch technique...this was your first time right??...just find that sweet spot between bog and total wheelspin

yeah, I was trying that all night. With those tires it seemed there was no difference. 2800rpm or slower, bog down and wheel hop. 2900rpm and higher, crazy wheel spin to around 5000rpm

[MikeSS]

Originally posted by AleroSS@Jun 3 2004, 01:31 PM
How far above/below sea level were you?

Not sure, I was near London Ontario west of toronto, it isn't too high, but not too low either

[jturkey69]

then maybe the rimms will help plant the front end, i honestly wish i had a wheelspin problem, but eh......keep at it tho, im pretty interested in those ECO times

[b-spot]

Originally posted by Oldsman@Jun 3 2004, 04:08 PM
2. killing gas mileage??????..............hummmmmmm. I get 31-32 on the highway. The gear ratio isn't changing enough to kill gas mileage. now if you went to like 4.10 then yes.

Okay, I'll admit I didn't actually pay that much attention to the effective ratio you are running now. At high way speeds that would only make a difference of 100-200 rpm's, so yeah, i'll give you that, not much of a difference.

As for launching.. wheel hop is my biggest problem. On a really hard launch i just feel bad for my car

[MikeSS]

Originally posted by b-spot@Jun 4 2004, 11:12 AM
As for launching.. wheel hop is my biggest problem. On a really hard launch i just feel bad for my car

LOL.

I just tell me car "Quick whining bitch and take it like a man (car?!?)"

[MikeSS]

Went out to the strip again last night. Had a blast!!! The stupid printing machine wasn't working so I couldn't get a print out of my times

Anyway, I got a new PB time with a 15.46 @ 89.03MPH. I was pretty happy about it. This is the first time I dragged with my new tires. The seem to work great, but I was having wheel hop problems. I kept experimenting with tire pressures and launch RPM's. I'll hopefully get it even lower next time.

I just wish I coulda got print outs to see my 60 foot times, 1/8 mile times, etc.

Most of my other runs were in the 15.5's and 15'6's