PDA

View Full Version : more acceleration with smaller tire diameter?


Stiv
02-27-2009, 10:49 AM
So, my (stupid?) idea is to replace stock 205/45 R17 with 225/40 R15.

Now, would this result in a better acceleration because of smaller tire diameter? I don't like to drive fast, just like to be the first after the green light :)

If this would mean just a small improvement in acceleration than I won't do it.

What would be the best (cheap?) way to improve acc? And no, I can't take the back seat out.

Thanks

Tamago
02-27-2009, 11:04 AM
So, my (stupid?) idea is to replace stock 205/45 R17 with 225/40 R15.

Now, would this result in a better acceleration because of smaller tire diameter? I don't like to drive fast, just like to be the first after the green light :)

If this would mean just a small improvement in acceleration than I won't do it.

What would be the best (cheap?) way to improve acc? And no, I can't take the back seat out.

Thanks

best cheap way to improve acceleration is nitrous


and the car will FEEL faster, but you'll really be going slower on a much smaller tire diameter

Morgan
02-27-2009, 11:06 AM
you could try swapping in a scion transmission, they have shorter (~sportier) gearing :)

TheRealEnth
02-27-2009, 11:15 AM
turbo or just accelerate hard to 40mph then relax

Tamago
02-27-2009, 11:26 AM
you could try swapping in a scion transmission, they have shorter (~sportier) gearing :)

wtf, scion transmission? that won't work, scion transmissions don't fit on toyotas :laugh:

btw OP is in a different country ;)

Morgan
02-27-2009, 11:29 AM
wtf, scion transmission? that won't work, scion transmissions don't fit on toyotas :laugh:

btw OP is in a different country ;)

it would probably rub anyway... :rolleyes:

(oh and LKQ does ship internationally)

TheRealEnth
02-27-2009, 11:29 AM
you can always throw in a GSXR1000 in the baby and call it a day.... dont know how long itll last.. ;D

Tamago
02-27-2009, 11:30 AM
it would probably rub anyway... :rolleyes:


ohhhhh she did NOT just go there

derickveliz2
02-27-2009, 11:40 AM
I went from 185/60/15 (23.7 in diameter) to 205/50/15 (23.1 in diameter) with MT the car feels much better as a sport car, speedo is off by 3-5mph (GPS) depending on speed. It does accelerates faster and breaks faster, feels like a sport car.

The down side is no more hiper mileage, used to get 40-45mpg now taking in mind the difference in tire diameters I'm only getting 36-39mpg (I guess it also has to do with the factor that the car feels sport and I'm enjoying it a lot).

For Highway driving it's OK for short periods of time, RPMs went up. But for back roads 5th gear rocks between 40 and 50 mph

If you don't mind the MPG this is the way to go and make your Yaris feel very SPORTY!

2cts

BrazdonW
02-27-2009, 12:22 PM
i thought about doing this too

a little more stress on the engine is all you have to worry about if you don't mind your speed and odometer being off along with slightly higher reving on highways.

try to use lightweight wheels and any other lightening you can to relieve a little stress off the engine

whooppee777
02-27-2009, 02:09 PM
i thought about doing this too

a little more stress on the engine is all you have to worry about if you don't mind your speed and odometer being off along with slightly higher reving on highways.

try to use lightweight wheels and any other lightening you can to relieve a little stress off the engine

listen to this guy. i raced him and even with everything i'd done to my car, his light weight 15's spanked my heavy ass 18's.

but that was before i was boosted :burnrubber:

CASTREX
02-27-2009, 03:37 PM
So, my (stupid?) idea is to replace stock 205/45 R17 with 225/40 R15.

Now, would this result in a better acceleration because of smaller tire diameter? I don't like to drive fast, just like to be the first after the green light :)

If this would mean just a small improvement in acceleration than I won't do it.

What would be the best (cheap?) way to improve acc? And no, I can't take the back seat out.

Thanks

You have a 1.8TS your car already has a much shorter gearing ratio than the US Yaris.

I would not do such drastic change. My suggestion, just replace the OE 205/45/17 tires for some stickier 205/40/17.

Haven't you heard what the Yaris is all about? With out a serious amount of money a yaris will never be fast on a straight line. However, with some suspensions mods it will rule on a curvy road.

Have you checked the TS section here? We have some information there that might be of interest for you.

If you want to improve acceleration:

- Remove weight (Rear seat weights a ton!)
- Intake ( You can use an intake for the US scion xD) CaliYaris, a sponsor of this site has a nice option (AFE intake)
-Exhaust. You have to go custom. 2.25" pipe from the cat back with straight thru resonators.
- Under drive crank pulley. CaliYaris has one also.

^^^
You will be at 120-125whp after this with a car that weights just above 2,300lbs

You will feel an improvement on the acceleration.

justjesus
02-27-2009, 04:00 PM
Lightweight weels make a nice diff. I went from stock 15" steelies on 185s, to Racing Harts that weigh about 9lbs and on 195/50-15s. Very noticeable difference on acceleration.

BrazdonW
02-27-2009, 06:39 PM
^^^ i believe that
you will even notice in 5th gear to amouth of pull you gain while cruising

ddongbap
02-27-2009, 06:58 PM
Or, you might go slower with too much Nos, as you may be burning more rubber.

BrazdonW
02-28-2009, 07:50 AM
listen to this guy. i raced him and even with everything i'd done to my car, his light weight 15's spanked my heavy ass 18's.

but that was before i was boosted :burnrubber:

just wait untill you get get some lightweight wheels along with that boost ;)
to both of our defenses though in that race, we both had girls with a little booty in our cars at the time lol