Having read this rather heated debate on battery relocation and its effect on handling (https://www.evolutionm.net/forums/sh...+tire+handling) , it seems that moving relative weight to the rear of the car improves handling.

I've finally managed to get some confirmation that my RS is a JDM spec (according to the ECU) in LHD, and alleged weighs in at under 1350 kg.

With this and the earlier thread in mind, I'm wondering if the handling will benefit in any way from the removal of the spare tire from the trunk. The effect should be the equivalent of shifting weight bias towards the front of the car, and if moving bias to the rear is a good thing, then is moving balance to the front a bad thing?

 

why dont you try removing it and find out

 

I haven't had my spare in my car for a LONG time! And tracked it/dragged it/and autox'ed it. no problems here.

 

Reducing weight is always a good thing. But you need to put it into perspective.

Your car is apparently 1350kg (2970lbs)
Your spare is probably 20kg.
Car - spare = 1330kg => a reduction of just less than 1.5%
Pretty small, but still a reduction.

Now if you assume 80/20 front/rear ratio (guessing here) you have:
1080kg front and 270 rear
Assume you remove 20kg directly from the rear, we have 1080kg front and 250rear => 81.2front/18.8rear so it's not going to be a night and day difference. In fact, if you can tell the difference between driving the car with a full tank and a half tank of fuel, then that's a similar magnitude of difference we're talking about here.

Where it might help is with the polar moment of inertia. That's the inertia of the car spinning about the yaw (vertical) axis. The 20kg (or however the spare weighs) is quite far away from the cg of the car so it will perhaps be a little less yaw-happy or less tendency of spinning.

Then again, the car is probably a lot more than 1350kg to be honest and the driver alone is like nearly 70-100kg so we're not doing a lot. I'd say go ahead and remove it. There's highly to be any adverse effects (save not being able to get home if you have a flat).

 

figure a ballpark F/R weight bias 60/40. otherwise our Bangkok friend has it right .

on a road course or at any track I have never seen anyone leave their spare in the car.
for street driving it has about as much effect as wearing a hat.

 

Thanks for the feedback, guys. Looks like no gain nor loss having the spare tire. Will remove it when track day comes about though

 

In that case, it will be even less noticable.

With spare : 60/40
Without : 61/39

Well, if you're Michael Schumacher taking it right to the limit then you might, just might notice the difference.

 

Oh, I'm DEFINITELY no Schumacher, that's for sure. Guess I'll just leave the spare in for street AND track then.

 

I leave mine in for daily driving but remove it at the track. Every little bit of weight reduction helps and this one is free so why not.....

 

I doubt the spare is that heavy. But a battery is just so much more heavy. I always thought it as less of a weight balance thing and more or less an old hot rodders trick of placing the battery over the right rear wheel to help traction on launch. I don't see how it could dramtically affect a car's handling.

 

I've done some track time with a sub in the trunk and it taken out (~40 lbs). The rear will rotate a bit more when cornering with the extra weight in the rear. BUT, you want the car as light as possible and you should make other adjustments to get the car to handle the way you want. Any extra weight will slow the car down in any time it needs to change speed or direction. The weight of the spare is probably about the same as ~4 gallons of gas (~25 lbs?).

 

hey x838nwy... what part of thailand are you at?.. capital i would assume?.. Are you thai?.. cuz i am from thailand.