Tire size/gear ratio and width theory

dsldubn
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Re: Tire size/gear ratio and width theory

Post by dsldubn »

sdwarf36 wrote:
KevinGale wrote:
sachilles wrote:I'm willing to bet you have more horsepower going to one of your wheels than I have going to all four of mine. :o :lol: :(
I wonder if anyone has put a smallblock chevy in a subaru?
It certiantly would improve the sound. :lol:
there's not much on this planet that has not had a small block put into it
http://forum.lsxtv.com/showthread.php?p=3759

...and Seth, for what it's worth, my car is a tiny bit faster with narrower, and shorter, tires. the weight savings probably helps, gear change, and less rolling resistance. I need to try to carry as much speed as possible in the corners though, being a low power car and not able to accelerate as much in the straights, so I think the best option would be a narrower tire with a stickier compound...sort of a compromise of both.
Jason Orzell
VW Rabbit turbo diesel, the green soot shooter
Terry.Murphy
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Re: Tire size/gear ratio and width theory

Post by Terry.Murphy »

I love the gearing of the 15" tire over a 16" tire for my RS, and yes I am still running the 4.11 final drive. I agree 100% with Nick's "Wider is not always better" philosophy but unfortunately I tuned the suspension (10k/8k rates) and stiffened to the chassis (the whole rear end was taken out and we replaced just about every bushing with custom made ones) so much that it requires tires that wide now for autocross(245's cause severe understeer).I wish I hadn't now as I bought a set of 245-40-16 slicks that I wanted to use this year thinking thinking the loss in weight (4-5 lbs/corner) plus the longer gearing would be a great thing for me. I may try them out at Okemo to see how they do but they were terrible for autocross. It was originally made to be an autocross car which it still is from time to time (and I DO use all of the 275's then) and that is what everyone runs on those cars so I happened to start on that avenue.

The way I look at the 275's now is that the car is so underpowered that I need all the cornering speed I can carry which they help quite a bit with.
Maybe when it gets a turbo powerplant it will be carrying so much speed I'll need all the tire!

Seth, do you have front WRX calipers on your RS? There are some 15" wheels out there that will clear the WRX calipers.

Kevin, this is for you! I have thought about this with my 383, but a modified or a GT1 car will get that powerplant.
http://www.youtube.com/watch?v=XnChYEfKepU
2010 Subaru Forester DD
1996 Legacy Outback Wagon - Winter Beater
2001 Impreza RS - Project Autox/Hillclimb/Track Car
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KevinGale
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Re: Tire size/gear ratio and width theory

Post by KevinGale »

Terry.Murphy wrote:Kevin, this is for you! I have thought about this with my 383, but a modified or a GT1 car will get that powerplant.
http://www.youtube.com/watch?v=XnChYEfKepU
I love it! Kevin Rhoads might want to look into this.
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sachilles
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Re: Tire size/gear ratio and width theory

Post by sachilles »

I do have wrx rotors and pad carriers. The caliper is the same between the rs and wrx. I have both setups. Finding the 15's that clear the wrx setup is hard and the tend to be pricey. So I figure its easier to go back to the smaller setup. Since it uses the same caliper and pad, it an easy swap, no need to mess with the hydraulic lines.
Sachilles
02 Subaru impreza (Donut) #66
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sachilles
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Re: Tire size/gear ratio and width theory

Post by sachilles »

Before this week, I was convinced I was going to do this.

In a bizarre turn of fate, my wrx wagon failed inspection due to rust. I kid you not just a week prior I had picked up a free impreza wagon with a bad 2.5 na motor.

So the least expensive thing to do is put the 2.5 out of scrappy into this new to us wagon and daily drive that. That means scrappy won't have a motor :( , yet I'll have a perfectly good 2.0 turbo motor in my wrx that has rusted away. That should fit into to scrappy just fine, as it was originally a wrx.
I wanted to finish the season with the N/A motor so I could stay in sp5, since this the first season where I could complete enough events to make a difference in points.
If things go according to plan, scrappy should have the turbo motor for Ascutney 2. So I'll have two events in sp3 and two in sp5.
I'll be retaining the 4.11 gear box for now as opposed to the wrx's 3.900. So I'll be able to see if I really want to go to smaller diameter tires or not in time for next season.

I always found the 3.900 gearbox a little tall for my liking with the 2.0 turbo motor. I'm anxious to see how it likes the 4.11.

Sadly, I'll be out of town for Okemo 2.
Sachilles
02 Subaru impreza (Donut) #66
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sachilles
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Re: Tire size/gear ratio and width theory

Post by sachilles »

Just re-reading the rules, I guess points are a non issue anyway. As I'd need to do 5 events total.
Sachilles
02 Subaru impreza (Donut) #66
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