MartinM

If I asked if it is worth having, I believe I would get a general consensus of "yes".

But are there any reasons why not to have it (on a P1)? Is it any more tricky to drive? Could it catch out a less experienced driver, and if so, how? Tyre wear? Tramlining? Likelihood of being spotted and making insurance invalid? etc?

MRK

In theory it probably would catch out the unwary because turn in grip is dramatically improved when cornering hard, so the tail will be and is on my car more willing to step out, but saying that when I have provoked this the tail moves out a bit then stays when you then plant your right foot, then everything is OK,, and she blasts out of the corner. But I’m expecting the tail to step out. I have as yet not tried to correct it.


The only problem I have noticed (mod done two weeks ago), and it may be another problem entirely, but my car now pulls to the left The geometry was checked again yesterday, and it still pulls to the left

My only theory is that with the more neutral toe settings tyre tread wear is a more important factor. My left front does have 2mm less tread than the right. And in the old days of 205Gti’s they had the same tread depth problem.


Any sensible comments from anyone on this??????


M

Viper

MartinM

I had my P1 done on saturday and it has been a relevation. I can honestly say that I haven't found a downside yet. The back of the car is a little bit more tail happy, but the turn in grip is amazing now. The car brakes dead straight now, this was never the case before and feels much more composed.

I am by no means an experienced driver at 27 and I feel that the car feels much more assurred now and I actually have more confidence in it as well.

I hope that this helps.

Phil

MartinM

Viper..

..so if the tail end is more happy(!), how do you correct it - traditional opposite lock/less gas or a FWD more gas?

I presume its opposite lock/less gas - the latter is for understeer (I think)

Memo to self : Make sure you understand this!!

MikeWRX

Well I know it is not a black science because I have a book that gives the details on how to make a inexpensive bumpsteer guage and measure it. I also understand ( I think ?? )that Powerstation or the shop that does the BSM uses various thickness shims between the steering rack and its mounts to alter the amount of bumpsteer. I would love to find a skilled person or shop in my area that had the equipment and knowledge to do it but i believe I will end up doing it myself ( if it is needed after checking the amount of bumpsteer first ) The procedure is quite time consuming and I still need a way to pull the car down but when your stuck in the land of Nascar and straight roads you find ways around the obsticles.

KF

Keep your foot in, and steer where you want to go. My suggestion would be to find out how to drive on the limit first, and then get the mod.
Sure it costs, but if you don't know what is going to happen when you overcook it, it is going to hurt just as much with or without the mod - and you get more from the mod being able to exploit it properly.

EDIT: to answer the rest of the question. The only downside I can see is that I get strange bald shoulders on my tyres, and passengers complain more. I have never heard anyone ask for the mod to be removed.

[This message has been edited by KF (edited 28 September 2001).]

MikeWRX

I have a US 2002 WRX and I am planning to add the Whiteline anti-lift kit to go with the 22m adj rear anti roll bar. Is the bump steer mod needed on new age impreza's ? and will it be as beneificial for a car equipped with an ALK ?

AJbaseBloke

MikeWRX,

Sadly this is a black science only doable by the wizards of ye olde England. Wish someone did it here, too.

Wonder how much it would cost to FEDEX the car over?

DavidRB

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by MRK:
<B>My left front does have 2mm less tread than the right. And in the old days of 205Gti’s they had the same tread depth problem.
Any sensible comments from anyone on this??????[/quote]You can go around roundabouts much faster in a Scooby, so you'll get more uneven tyre wear!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by MartinM:
<B>Viper..

..so if the tail end is more happy(!), how do you correct it - traditional opposite lock/less gas or a FWD more gas?

I presume its opposite lock/less gas - the latter is for understeer (I think)[/quote]Absolutely not!!! That method is almost guaranteed to send you spinning in the opposite direction towards the nearest solid object on the outside of the bend!!!

I'm sure Simon can explain this far better than I can, but 4/AWD cars are prone to bad lift-off oversteer. If the rear starts to slide and you lift off and turn in the opposite direction, chances are, the front tyres will grip and the car will turn abruptly in the other direction.

To slide a Scooby succesfully, you have to slide all four wheels, unlike a RWD car where you would opposite lock so that the front wheels were pointing in the direction of travel. If you opposite lock in a Scooby, the front tyres will grip and pull the car out of the slide, but it will want to keep rotating. If the rears are still sliding or you don't straighten up the steering quickly enough, then the car will keep turning in the direction you're steering and you'll spin off in the other direction.

If you get the rear sliding, it's far better to ease off a little throttle (but don't close it) and keep the wheels pointing in the direction you want to go. As long as you aren't too far beyond the limits of adhesion, then the Scooby will just sort itself out and you can carry on. You, however, may need to get some clean pants.

I had the bumpsteer mod back in February and I still think it's the best mod for an Impreza. You can read what I thought about it

Neanderthal

iTrader: (6)

I accidently had the rear end step out by trying to accelerate out of a juction to quickly (it had been raining). This happened a week after I brought the car (Silver MY97).

It all happened so fast that I'm not entirely sure what I did to get out of it but I had just been karting so I presume I put opposite lock on and the back end snapped back straight. If I'd have been going faster I'm sure it would have snapped back in the other direction just as DavidRB suggests.

David is also correct in that I needed a change of underwear when I got home.

I've been a lot more careful since then.
Once bitten twice shy as the saying goes.

Matt