What mods?

[dougc]

Morning fellow motorers--I haven't posted here in a long time.

Anyhoo...I just put performance tires on my Coop and was curious what else I should do. For the record, I read NAM and really wanted local input. I drive the car daily (especially true now that gas prices are up and my "other" is a diesel truck).

I was thinking a rear sway bar, a bigger front sway bar, and thats were I hit a snag. I'm guessing a stage one or two engine kit from from MiniMania (unless there is anyone local I should know about).

So, thanks and I'll wait for responses.

[weezer2282]

Rear sway bar at either 19mm or 22mm. No need for a front sway bar really. Front camber plates. Lowering springs or coilovers. Cold air intake, supercharger pulley, and exhaust. Brake upgrade. ECU tune.

[Ike]

I would second what weezer has said. I recently had a 15% installed and it seemed to make a great difference. I'm in the process of adding a CAI and freeing up the exhaust (header with pre-cat deleted and one-ball exhaust).

I want to added camber plates soon too (to help prevent mushrooming and for the added camber). Ireland engineering sells "fixed" camber plates and from what I've read are the preferred. If you don't track the car a 19mm rear sway is enough (a 22mm might be too much for street use).

If you want to experience what a 15% pulley feels like, shoot me a PM.

Ike

[justintime]

depends on what your wanting to achieve honestly... I wouldnt add the front sway bar unless your aiming for loads of understeer ;] If you do go with a front sway I highly recommend getting a rear sway and front camber plates

[dougc]

Thanks for the replies so far--some things I forgot: my cooper is normally aspirated. I'd like to get better performance--I realize the engine is small and there is more to performance than speed. For example, I like to take the corner around the "Flame of Friendship" sculpture down town as fast as possible--so far the best I've done is 30 mph. My other favorite corner is the entrance ramp from Commerce to 281.

So I want to get better cornering and increased peppy-ness to the engine.

I'm glad to hear the front sway bar might be too much. What is the general concensus on strut braces?

[Ike]

Strut braces are ok. I had an M7 brace and sold it, because it didn't make that much of a difference to me and it pushed my hood out a little (not permanent, but still). If you want to add some peppy-ness and cornering ability, I'd pick up a CAI, Ireland camber plates, and 19mm rear sway (in that order). That will give you a good start.

:)

[weezer2282]

It being a normally aspirated Cooper makes a big difference. You should look at getting a Cooper S front sway bar along with a 19mm or 22mm rear sway bar. Or leave the front sway bar alone and go with a Cooper S rear sway or 19mm bar. Take-off stock Cooper S bars can be had for little money and are larger than the regular stock Cooper bar I think.

The Ireland fixed plates are plenty for street. I have them and they work fine. Tire wear is improved quite a bit with them. Also look at lowering springs with shorter struts and/or coilovers if going for maximum performance or the lowered look. Some coilovers can be had for relatively inexpensive with camber plates included.

TSW (Texas Speed Works) also sells some nice stuff and they are located in the Dallas, FT. Worth area.
http://www.txwerks.com/servlet/StoreFront

As far as engine performance probably all that can be done is CAI, exhaust, and an ECU flash. Not too much else worthwhile to do.

[justintime]

the cooper motor I would just get and intake, header, exhaust if you feel like having a lot of noise.. no ecu flashes I have seen have been worth it for the cooper minus getting a tune from jan.

if you have some money burning a hole in your pocket id get a head/cam/stroker :}

okok

I would go with a 22mm rear sway with cooper s front sway or if you have the sport package (means you already have the cooper s sway)

if you leave the stock non sport package or s front swaybar I would go with the 19mm.

depending on how hardcore you want to go.. I would find yourself some coils with camber plates..

if your on a budget I would do springs and camber plates/ alignment

strut braces dont do much at all.. if you want to increase rigidity look into the m7 uss or tsw has a under carriage brace also.

or you could do what I did and strip it :D

[dougc]

So--CAI, linear springs to lower the car, camber plates and two sway bars it is. I haven't looked, but my mini is pretty basic. I would really be surprised if I had a sports suspension. This car is my daily driver and it turned out to be much mor efun to drive than I expected. So, now I want to tune it more to my liking (and less average!).

As for getting a supercharged car, it would be a hard sell;but, I like the idea of getting a Cooper S.

From older threads, it looks like 210 Performance has expereicen with minis--does anyone have experience with them?

[weezer2282]

From older threads, it looks like 210 Performance has expereicen with minis--does anyone have experience with them?

I'm not sure if 210 Performance is still around. I have no personal experience with them, but I think I knew someone that had some work done there and it wasn't a smooth experience.

I do have experience with Prestige Tuning and they have a lot of experience working on MINIs. They do my regular maintenance and have done some upgrades on my MINI. I would recommend them. :thumbsup

http://www.prestige-tuning.com/about_us.html

[Ike]

I will second Prestige tuning. I prefer to do most of the work on my car myself (or with help from friends - thanks Keith), but Prestige does a pretty good job. I had them flush the cooling system when I purchased my 03 mini. I wasn't sure if it had been done before, but it's good preventative maintenance, particularly in TX heat.

They are located near I-10 and 1604.

Ike

[justintime]

what kinda traction control do you have? asc or dsc? and what do you seats look like?

also, don't forget your alignment.. all those mods are pointless without it

So--CAI, linear springs to lower the car, camber plates and two sway bars it is. I haven't looked, but my mini is pretty basic. I would really be surprised if I had a sports suspension. This car is my daily driver and it turned out to be much mor efun to drive than I expected. So, now I want to tune it more to my liking (and less average!).

As for getting a supercharged car, it would be a hard sell;but, I like the idea of getting a Cooper S.

From older threads, it looks like 210 Performance has expereicen with minis--does anyone have experience with them?

[k-huevo]

As for cornering faster; practice, practice, practice. The standard Cooper’s suspension is a handling & comfort gem with OEM size spec tires on the street; keep it stock until something wears out.

Reducing weight is a cost effective way to improve acceleration, start with the rear seats and seat belt hardware, and avoid carrying unnecessary stuff around.

A clean air filter will help keep engine performance near peak. After that it depends on how much money you have to throw at the motor. If you have the budget a ported head will net worthwhile gains; once volumetric efficiency (VE) is improved, bolt-ons for the intake and exhaust side will begin to make more of a difference than originals. Beyond breathing improvements, power options get real exciting with exponentially increasing costs to match.

If you want to feel like you’ve gained a bunch of torque without a bunch of money spent, go Sprint Booster (http://new.minimania.com/web/Item/NME1900/AddedFrom/Search/InvDetail.cfm) .

[justintime]

+1 to what keith said..

also remember the stock mini understeers a lot.. and removing weight nets great accerleration gains AND cornering advantages.. however removing weight from the rear only will cause the car to gain off throttle understeer. so try to level out the playing field with removing the battery/moving it somewhere else, maybe lighter cosmetic parts (cr hood ex) your spare tire also weighs a good amount and can be removed easily. As far as the cooper goes I think weight is the only thing you can go all out on to gain a good amount of performance for cheap...

[weezer2282]

A light rear would give more lift-off oversteer. It will help the car rotate and there will be lesser front end pushing or understeer. :thumbsup

[justintime]

A light rear would give more lift-off oversteer. It will help the car rotate and there will be lesser front end pushing or understeer. :thumbsup

hate to argue but just think of it in terms of a midship car. its hard to rap your mind around but if you remove to much weight from the rear of the car it will surely understeer off throttle, you will gain more traction much like an lsd does when on the throttle cornering as the weight up front will help with front grip under acceleration

[justintime]

I asked my buddy ivan as he is more literate than I am to explain it better so you can understand...

When you were in science class, they probably taught you about Netwon's laws of motion. Here's the first one:


Quote:
Originally Posted by Isaac Newton
Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.

In this case, the object is your car, and the external force is your steering input. Instead of thinking of your car as one solid brick, we'll get silly with it. Think of your car as a barbell where you've got one 45 lbs plate on one end, and one 25 lbs plate on the other. Pick it up, and run with it, heavy end first. Now as you're running, turn a corner. Because there's more weight in front (the 45 lbs plate end), it will resist your attempt to turn it moreso than the lighter rear (the 25 lbs plate end). The weight bias is towards the front. In a car, this equates to understeer. If both ends had the same weight, they would both resist your attempt to change their direction equally, resulting in a "balanced" setup. If there were more weight in the rear, this would result in a setup that wants to oversteer.

Of course, there are tons of other factors that contribute to balance, but that's just taking weight distribution into account by itself. Stuff like driving style, spring rates, sway bars, suspension geometry, etc, will affect your balance and can even neutralize a nose-heavy car's tendency to want to understeer. Look at Porsche. They've got the 911's engine hanging out behind the rear axle, but nowadays a factory 911 Carrera will understeer due to its suspension tuning.

[weezer2282]

A mid-engine or rear engine style car has a drastically different weight distribution than a MINI. The center of gravity would be very different between the different styles of cars.

Removing weight from the rear to me is like driving around with hardly any gas. The rear end will want to dance more and will come around easier. The front will stick the same since there was no weight change in the front. Lift-off will send more weight to the front and make the rear even lighter and thus it will oversteer more when lifting off or hitting the brakes during cornering.

If you've ever driven a pickup or a SUV with not much gas in the tank and in the rain you probably would experience the effects of this lift-off oversteer from a light rear end. I've experienced it myself in a SUV and in my MINI.

I think I do understand what you are saying though about the rear and mid-engined cars, but that is a completely different beast. :thumbsup

With the MINI less weight on the rear tires means less traction since there is less traction between the rubber and the road. With a mid-engine or rear-engine it would be more of a momentum and traction issue.

Just think of how a rear-sway bar works. It transfers more weight to the front tires to increase their grip and there is less weight on the rear tires, so the rear actually has less grip. It makes the car oversteer more as you increase bar stiffness and it is decreasing the weight on the rear end to do this.

[justintime]

A mid-engine or rear engine style car has a drastically different weight distribution than a MINI. The center of gravity would be very different between the different styles of cars.

Removing weight from the rear to me is like driving around with hardly any gas. The rear end will want to dance more and will come around easier. The front will stick the same since there was no weight change in the front. Lift-off will send more weight to the front and make the rear even lighter and thus it will oversteer more when lifting off or hitting the brakes during cornering.

If you've ever driven a pickup or a SUV with not much gas in the tank and in the rain you probably would experience the effects of this lift-off oversteer from a light rear end. I've experienced it myself in a SUV and in my MINI.

I think I do understand what you are saying though about the rear and mid-engined cars, but that is a completely different beast. :thumbsup

With the MINI less weight on the rear tires means less traction since there is less traction between the rubber and the road. With a mid-engine or rear-engine it would be more of a momentum and traction issue.

Just think of how a rear-sway bar works. It transfers more weight to the front tires to increase their grip and there is less weight on the rear tires, so the rear actually has less grip. It makes the car oversteer more as you increase bar stiffness and it is decreasing the weight on the rear end to do this.
the concept is the same, different beasts but same thing. both were talking about momentum and both are efected the same way by it. and yes the sway bar transfers weight to the front, but main reason you loose grip faster in the rear with a stiffer bar is stiffer part of the car looses traction first. its alittle more basic with springs and dampening in that matter as a lot of it has to do with load transfer as you said (refering to the sway bar) I understand where your coming from

http://www.drivingfast.net/car_control/oversteer.htm

Scroll down to "Rear wheel drive, rear engine e.g. Porsche 911":


Quote:
Originally Posted by drivingfast.net
Rear engine, rear wheel drive vehicles such as the Porsche 911 can oversteer for different reasons to front engine varieties. In this case most of the vehicle weight is over the rear wheels, leading to greater levels of natural grip at the back, which should lead to an inherent low risk of oversteer. However, there is another force at work here – momentum. Objects with greater mass carry more momentum and are harder to change direction at speed. In the case of rear engine cars, the rear has more momentum than the front which can lead to a greater risk of oversteer as a result of braking or lifting off mid corner.

Like I said though, it's more complicated than just weight. Suspension setup and driving style have a lot to do with it, as well. He's basically looking at weight as only acting in the vertical axis (up and down, adding or subtracting weight to push down the tires), but when you're cornering, you're also transferring weight sideways.

Think of it like this: Put a really heavy lead ball in the boot of your MINI and enter a corner. Initially, the car will be balanced or understeering as the ball begins to roll. As soon as the ball hits the side of the boot, it exerts force towards the outside of the corner, which would cause it to start to oversteer.

In other words, weight in a car doesn't only push down. If it did, adding weight would always increase cornering grip. Unfortunately, when you're cornering, the weight also pushes sideways, towards the outside of the corner. If the weight is in the front, it will push the front towards the outside of the corner, aka understeer. If it's in the back, it'll push the back towards the outside of the corner, aka oversteer.

[weezer2282]

however removing weight from the rear only will cause the car to gain off throttle understeer.

This statement here is still not accurate. I understand the physics of cornering and everything you are saying.

Yes, adding a lead ball to the rear so the rear has more percentage of weight than the front would cause it to act like a rear-engined Porsche. I am not arguing that point at all.

The point I am making is that in stock form with a full tank of gas the MINI has more percentage of the weight over the front than the rear. Take 100-200 pounds out of the rear or have a very low tank of gas and the percent of weight on the front is still significant while the rear has less. When cornering under a high load then lifting off with this situation the rear will be more likely to come around. This can be a good thing if done to a stock MINI since it understeers in stock form, so it will help it rotate around the corner and possibly oversteer.

For the specific case of the MINI (front engine, FWD) you have to think of it in terms of grip and less so for momentum. If you remove weight from the rear the front will always have about the same level of grip, but the rear will have less and less grip than the front. This is also why the Cooper S has the battery in the rear. They put it there to achieve better balance and grip at the rear and to keep away from a "light" rear end. The ideal goal would be a 50/50 weight distribution, but that is near impossible with a front drive car.

I didn't mean for this to turn into this. I actually just thought you had confused under and over steer. Removing weight from the rear in the specific case of the MINI will cause it to oversteer more not understeer though. The GP is also a good example. Most of its weight reduction is in the rear and it handles better and was designed as more of a track car. As far as I know it doesn't understeer more than a stock MINI, in fact I think it probably corners better and understeers much less with maybe a hint of lift-off oversteer.

[weezer2282]

http://www.automotivehelper.com/topic49596.htm

The post by replicant_008 is good.

[justintime]

its just a conversation, I love talking suspension as chassis engineering is what im studying.. anywho i'll put more effort into a post later.. ps gp=more understeer than the stock cooper s.. driven a couple of them. not much as the weight difference in the rear isn't very significant honestly. the lead ball was an example to overexhagerate the fact that in cornering there is momentum going towards the sides of the car no matter how much it weighs. not just frontwards and backwards. even though the mini is a lightweight car (and dont get me wrong it does play a large roll in what were discussing) it is still a very heavy object and is not disqualified from being effected from momentum :thumbsup
grip is only what the tires can give, and that is greatly effected by more than just weight distribution. suspension and driving make a huge difference on if the car will understeer or oversteer. but in basic if all that was aside the car WOULD understeer if the rear was unbalanced to the front (meaning lighter) all cars fwd rwd midship are balanced.
This statement here is still not accurate. I understand the physics of cornering and everything you are saying.

Yes, adding a lead ball to the rear so the rear has more percentage of weight than the front would cause it to act like a rear-engined Porsche. I am not arguing that point at all.

The point I am making is that in stock form with a full tank of gas the MINI has more percentage of the weight over the front than the rear. Take 100-200 pounds out of the rear or have a very low tank of gas and the percent of weight on the front is still significant while the rear has less. When cornering under a high load then lifting off with this situation the rear will be more likely to come around. This can be a good thing if done to a stock MINI since it understeers in stock form, so it will help it rotate around the corner and possibly oversteer.

For the specific case of the MINI (front engine, FWD) you have to think of it in terms of grip and less so for momentum. If you remove weight from the rear the front will always have about the same level of grip, but the rear will have less and less grip than the front. This is also why the Cooper S has the battery in the rear. They put it there to achieve better balance and grip at the rear and to keep away from a "light" rear end. The ideal goal would be a 50/50 weight distribution, but that is near impossible with a front drive car.

I didn't mean for this to turn into this. I actually just thought you had confused under and over steer. Removing weight from the rear in the specific case of the MINI will cause it to oversteer more not understeer though. The GP is also a good example. Most of its weight reduction is in the rear and it handles better and was designed as more of a track car. As far as I know it doesn't understeer more than a stock MINI, in fact I think it probably corners better and understeers much less with maybe a hint of lift-off oversteer.

[weezer2282]

I still think your reasoning is flawed.

This is about the handling of a Fiat X1/9 which was a mid-engined car like an MR2:

Despite its mid-engined configuration, weight distribution was not perfect, the normally excellent handling soon worsened with wet or slippery conditions as the front wheels could struggle to gain grip under the relatively light front end of the car.

http://en.wikipedia.org/wiki/Fiat_X1/9

The X1/9, MR2, and older Porsches were all known to understeer like this due to a light front end. The opposite could be applied to the MINI with a light rear end. A lighter rear end would make the MINI oversteer more.

I've never heard of lift-off understeer or off throttle understeer either. If you lift-off or are off throttle and on the brakes this will make understeer go away.

MINI's can experience lift-off oversteer depending how the suspension is tuned and less weight on the rear would also encourage it. I beg to differ that the GP would understeer more than a stock Cooper S.

The mid-engined and rear-engined cars experience snap/lift-off oversteer at the limit due to the location of the motor mass and the inertia from the motor makes it want to swap ends, plus at the same time some grip is lost due to weight transfer to the front. This is a little different from lift-off oversteer in a MINI which is caused mostly by a light rear and the weight shifting to the front wheels. In a MINI you need to get back on the throttle to get some weight transferred back to the rear to correct it. In a mid-engined or rear-engined car a lot of the time you'll end up in a terminal spin because the sliding rear wheels are usually the powered wheels too and there's quite a bit more inertia trying to swap ends with the motor back there than there is in a front engined car.

I do have a degree in Mechanical Engineering too, so I've taken my share of physics, statics, and dynamics courses.

[justintime]

gotta run to lunch..
but quick comment.. like its been stated a lot has to do with suspension and driving technique as well

I still think your reasoning is flawed.

This is about the handling of a Fiat X1/9 which was a mid-engined car like an MR2:



http://en.wikipedia.org/wiki/Fiat_X1/9

The X1/9, MR2, and older Porsches were all known to understeer like this due to a light front end. The opposite could be applied to the MINI with a light rear end. A lighter rear end would make the MINI oversteer more.

I've never heard of lift-off understeer or off throttle understeer either. If you lift-off or are off throttle and on the brakes this will make understeer go away.

MINI's can experience lift-off oversteer depending how the suspension is tuned and less weight on the rear would also encourage it. I beg to differ that the GP would understeer more than a stock Cooper S.

The mid-engined and rear-engined cars experience snap/lift-off oversteer at the limit due to the location of the motor mass and the inertia from the motor makes it want to swap ends, plus at the same time some grip is lost due to weight transfer to the front. This is a little different from lift-off oversteer in a MINI which is caused mostly by a light rear and the weight shifting to the front wheels. In a MINI you need to get back on the throttle to get some weight transferred back to the rear to correct it. In a mid-engined or rear-engined car a lot of the time you'll end up in a terminal spin because the sliding rear wheels are usually the powered wheels too and there's quite a bit more inertia trying to swap ends with the motor back there than there is in a front engined car.

I do have a degree in Mechanical Engineering too, so I've taken my share of physics, statics, and dynamics courses.

[justintime]

ok, ivan found this link.. pretty simple

http://www.rallylights.com/other/stuning.htm#weight

http://www.international-auto.com/index.cfm?fa=ad&aid=39

[weezer2282]

For steady state cornering those would generally apply. For a lift-off state they might not.

[justintime]

For steady state cornering those would generally apply. For a lift-off state they might not.

the problem I think your having is simple but that of a mathmatical one. if your going slow (like taking onramps slow stuff around town exc) your theory would apply and you would be completely right.. however were talking true handling on a track or autox (or I guess if your running a corner at enough speed on the streets to pull some g) once your under a lot of load from g forces the car will understeer. now add a sway bar exc if you lift off the throttle, trail brake, exc.. soften the front suspension, add neg camber up front blah blah blah it will naturally oversteer as thats what you have tuned the suspension to do. But on a stock cooper removing bunches of weight from the rear will make it understeer. you can counter it though by doing things like relocating the battery (as done on the cooper s) lighter materials up front exc. but you don't want to throw the balance of the car off exp with removing weight from the rear.. unless understeer is your goal lol. :thumbsup

[justintime]

For steady state cornering those would generally apply. For a lift-off state they might not.

also, when you lift off weight goes to the front of the car.. if there isn't enough momentum when this happens the front will push more than the rear and you will have understeer. this is easily dialed out with small amounts of suspension tuning. however to really fine tune you must keep this in mind as it will be a crutch.. the idea is to tune the car to handle as balanced as possible so it is very easy to drive at the limit. when this is acheived the car will be fun to drive and won't be unpredictable. the mini is almost perfectly balanced for a fwd car stock. all my point is if you remove weight from the rear (which I recommend) remove it from the front as well. unless hes going all out though, It won't matter much really. i would recommend relocating the battery behind the seat or in the rear :thumbsup

btw.. it will still understeer under throttle as well. but you can find more grip thus preventing power-undertseer

[weezer2282]

I will try to break this down and see if you agree.

Assumptions for your reasoning that removing weight from the rear and shifting the weight distribution towards the front will create more understeer:

1) Constant cornering speed like a skid pad test.
2) Overall weight of vehicle is unchanged. More weight is just distributed towards the front than the rear.
3) Front will lose grip sooner than rear cause of more weight at the front end. Car will understeer.

My reasoning that removing weight from the rear will make it more tail happy and more prone to lift-off oversteer:
1) Throttle is lifted or brakes are hit when under cornering loads. Likely more noticeable at higher speeds.
2) Overall weight of vehicle is lighter. Front is the same weight. Rear is lighter than stock.
3) Rear will slip before the front due to less weight on the rear tires and less mechanical grip at the rear. Front will continue to have the same grip as it did stock. Car will be more throttle steerable.

I'm just saying it will do this more: http://en.wikipedia.org/wiki/Lift-off_oversteer

And it will never have lift-off understeer. Although it could understeer to a point under a constant throttle corner where the same speed and amount of throttle is held constant thoughout the corner.

[justintime]

I will try to break this down and see if you agree.

Assumptions for your reasoning that removing weight from the rear and shifting the weight distribution towards the front will create more understeer:

1) Constant cornering speed like a skid pad test.
2) Overall weight of vehicle is unchanged. More weight is just distributed towards the front than the rear.
3) Front will lose grip sooner than rear cause of more weight at the front end. Car will understeer.

My reasoning that removing weight from the rear will make it more tail happy and more prone to lift-off oversteer:
1) Throttle is lifted or brakes are hit when under cornering loads. Likely more noticeable at higher speeds.
2) Overall weight of vehicle is lighter. Front is the same weight. Rear is lighter than stock.
3) Rear will slip before the front due to less weight on the rear tires and less mechanical grip at the rear. Front will continue to have the same grip as it did stock. Car will be more throttle steerable.

I'm just saying it will do this more: http://en.wikipedia.org/wiki/Lift-off_oversteer

And it will never have lift-off understeer. Although it could understeer to a point under a constant throttle corner where the same speed and amount of throttle is held constant thoughout the corner.



your correct at low speeds with the weight (and im talking about removing weight not just relocating it although either way you are still changing the balance of the car) , trailbraking will transfer weight diagonally to the front resulting in oversteer. however same thing applies if you dont have weight in the rear for this to happen the what does happen? lifting on in steady state cornering will rotate the car and correct understeer.. however im talking about understeering off-throttle into the corner. if you go into the corner too fast or even just at the limit the car will understeer if you remove to much weight from the rear.

what im saying is much more basic. lets put the mini on a skidpad say the suspension is set up to be 100% even (over steer/understeer), theres no driver to manipulate cornering efects and braking techniques. tires are even exc. when you take the car to the limit and enter the corner off throttle, or stay on the throttle either way its going to understeer. if the car is understeering as it is lifting off throttle mid corner will only counter the understeer alittle bit. like I said and ivan said suspension, driving technique, tires (suspension tuning in general) will effect the car a lot. ill see if ivan can put some input on this as im bad at explaining stuff lol

[dougc]

Justintime--where did you get the blackout trim for your S? I like that look.

[justintime]

Justintime--where did you get the blackout trim for your S? I like that look.

I painted it, i'm now using an astro black cooper grill though. and I have a cooper :D http://img.photobucket.com/albums/v108/kanlocadal/MOTD031-1.jpg


you can get grills from outmotoring.com as well as many other mini vendors. you can get headlight ring vynals from vynal styles

[dougc]

thanks--does that s grill cool things down or is it cosmetic?

[justintime]

mine doesnt, its stock. but the aero grill supposedly cools things down a little. I know the coopers in the challenge cars used them and the cooper s bumpers to help cooling. I havn't seen any actuall numbers but they look great cosmetically

(or were you talking about the scoop?) I have a diverter that goes to my intake)

[dougc]

Nope grill. Thanks again for the heads up on the black out--I checked their site and noticed at some time in the future, vinal styles is going to have a complete black out kit.

[justintime]

hey weezer, I remembered you while I was having this discussion with another buddy of mine. any who I thought you might appreciate this

so, a lot of people I have been talking to seem all agree that a lighter rear end will oversteer. anywho, I disagree. Ive talked to ivan a lot about it but i still cant explain this very well so I found my trusty chassis engineering book and copied this to adam but thought I would go ahead and put it here too. if yall want more details exc I can post them just kinda busy at the moment

discuss

chassis engineering book from herb adams. he talks about weight bias and all this good stuff along with the math so you can see it as I am half retarded and can't explain these things.. any who

the important concept to understand is that the traction available from a tire is dependent on its vertical load. the confusing aspect is that the percentage of traction improvement goes down as the load goes up. (most of the math also is coming from a big tire performance curve thing he has that I dont hav time to copy down)

example on (saying the car is weighted perfectly)

car weight: 3000lbs
front end weight: 50%
left side weight bias : 0
load transfer from cornering: 0

all four corners are at 750 lbs and the traction available is 3400 (taken from his tire performance equation chart thing)

this theoretical car has 750lbs on each wheel. using the tire performance curve on you can see that you wuold have 850lbs of traction available at each wheel. the total traction would be 3400lbs and the cornering force would be 1.13gs. to find the total cornering forces in g's you would divide the total traction by the total weight.

total cornering force = traction/weight

total cornering force = 3400/3000= 1.13 g's

this sounds pretty good until you realize that the weight will transfer from the inside tires to the outside tires as the car develops cornering force going around a corner.

as soon as a car starts to go around a corner its vertical tire loadings willchange. because of the cornering force, weight will be transferred from the inside tires to the outside tires. this change in loading is dependent on the conering force (g's) the car track width (t) the heighth of the center of gravity (h) and the overall weight of the car (w).

lateral weight transfer = w x g's x h/ gravity x t

you can reduce the equation by factoring in a 1.0g cornering force, the amount equal to the force of gravity, and then the formula would be:

lateral weight transfer = wh/t

for our example lets say our car has a center of gravity height of 20 inches. with a track of 60 inches. the weight transfer for a 3000lb car at 1.0g cornering force would be

lateral weight transfer = 3000 x 20/60 = 1000lbs

ok im skipping a lot as that is basically waht you need to know for the example for a front heavy car (less weight in the rear)

to see the effect of having a front heavy car, lets see what happens when we make the front end weight 60% with no left side weight bias and our normal 3000lb car. there would be 1800 lbs. on the front tires and 1200 lbs on the rear tires. the static weights, cornering weights and traction available would be as show in chart 2-4 (which is also huge and i dont want to copy it). plugged into the formula, it would look like

total cornering force = 3130/3000 = 1.04 g's

note that this is the average cornering force.

this total is misleading because if you look at just the front-end weights and traction forces in chart 2-4 you see that there is 1750lbs of traction for pulling the front end weight of 1800 lbs around corners. the front end cornering force would then be

front cornering force 1750/1800 = .97 g's

at the rear as shown in chart 2-4 there is 1380lbs of traction to pull 1200lbs of weight around corners. this means the rear cornering force will be

rear cornering force = 1380/1200 = 1.15g's.

this analysis shows that the car in this example will not only corner slower than one with equal front to rear weight distribution, but it will also understeer in the corners. if the front traction is not able to pull the front weight as well as the rear traction can pull the rear weight, the front end wont stick as well as the rear end.

hope that helped man