318is modifications for the track (and a road car)

[Jem]

I've currently got a M40 powered 318i, which is great as a daily run around, but I'm looking to start doing 7 or 8 trackdays a year. I'm thinking of selling the the 318i and buying a 318is to use as my daily drive and for doing trackdays. What modifications would you guys suggest making to a 318is for the track?

[m3ben05]

Why not just keep the 318i as a road car then buy a 325 as a track car? The 325 is not much more expensive than the 318is and a lot more powerful.

As far as mods go,

Decent suspension/ bushes
Uprate the pads, disks and get some braided hoses
Strip out the interior, fit a roll cage and a couple of bucket seats

That will do you for starters, if you want more you could -

track tyres (yoko a048's)
fibreglass panels
Big brake kit
Chip the engine

[Andy335Touring]

It depends on your budget and what sort of a comprimise/bias you are happy with, a roll cage/bucket seats/harnesses would be advisable for a car used for plenty of track days but you might not want that on a daily driver.

[Lordschleife]

Why not just keep the 318i as a road car then buy a 325 as a track car? The 325 is not much more expensive than the 318is and a lot more powerful.

As far as mods go,

Decent suspension/ bushes
Uprate the pads, disks and get some braided hoses
Strip out the interior, fit a roll cage and a couple of bucket seats

That will do you for starters, if you want more you could -

track tyres (yoko a048's)
fibreglass panels
Big brake kit
Chip the engine

But a 318is is better in the corners, and surely thats what track days are all about at the end of the day?
Not that 325 is a bad track car, used to have one as my 'ring bitch

Agree with the rest of the stuff, decent brake fluid too

[m3ben05]

Fair enough, iv never driven a 318is so i cant comment. I guess it would depend on how much you want to change on the car. I would imagine that a 325 with decent suspension would be better handling than a standard 318is.

[M5pilot]

Suspension and bushes are your number one upgrades on a track.

Get some GAZ coilovers and Powerflex bushes.

If you then feel you need more power then do some upgrades to the engine/management.

A 325i will be faster on the straights and maybe exiting out of corners but the 318iS will be much better in the corners.

[Jem]

I want the better balance of the 318is, as I want the car for handling over power. Looks like it's a pretty simple case of sorting the suspension and breaks then, and stripping it out is I want to take it that far.

[Dan318-is]

Fair enough, iv never driven a 318is so i cant comment. I guess it would depend on how much you want to change on the car. I would imagine that a 325 with decent suspension would be better handling than a standard 318is.

318is and 325i have the same suspension!! exactly the same!

[Lordschleife]

Surely the spring rates are different?!

[DanThe]

Only the front springs, obviously to account for extra weight up front but the struts, ARB, bushes etc are the same.
The rear ARB can be 12mm on a 325 unless its a Sport or its got M-tech suspension which means it would have 14.5mm like the iS