Upgrading a 320d ED to M Sport Suspension

[RobM77]

I've been offered a 2011 320d ED by a family member at a ridiculously low price. My current daily, a 2007 320d SE, is nearly ten years old now and has done 152k miles, so this much fresher example is obviously very tempting indeed, as is the markedly better economy with the high mileage that I do. The trouble is that I test drove it last week and it didn't handle or steer as well as my SE spec 320d. I don't give a monkeys about the power output, I'm just interested in handling, so I was wondering what would be entailed in getting it up to M Sport spec. Springs and dampers are obvious - are the bushes the same? Am I right in saying that M Sport suspension is designed around the 17" wheel, so I would have to buy a set of these too? Is there anything else electronic that would need changing, such as the speedo calibration, DSC etc?

Thanks in advance.

[f1nn]

Never build a car you can buy.

[RobM77]

f1nn said:

Never build a car you can buy.

That applies in most cases, where the car plus upgrades usually cost significantly more than that better car would in the first place. In this case though, the ED is such a bargain that this may well be the best route. Plus, it's a car I've known since new and I know it's been looked after unbelievably well.

[ian in lancs]

I would think you'll be in for dampers, springs, anti-roll bars and bushes. Best to look at realoem and look at the part number differences for the suspension. Tyres are part of the suspension so BMW would have tuned it on larger wheels. I look on eBay for wheels but go aftermarket for suspension. BMW won't be cheap. Anyway, I agree with the adage don't build what you can buy. Be dead money too.

[Smuler]

First thought I had was, is there anything wrong with the newer car if it doesn't handle as well as yours? I can't think why, so I would check it out; something could be worn ?

I don't know your answer on suspension differences; but M Sports were sold with 18s, you can fit 17s as I did so and were excellent.

What I would do, for a definitive answer, is get your car's VIN and then get a VIN from a similar M sport and then either go to a reliable BMW dealers parts dept or there are online catalogues, REALOEM I think is used, and see the different parts like for like.

I would say, a big part of M Sport is sport seats, that makes the whole ride feel so different anyway, plus is the ED car on RFTs and yours isn't, that makes a big difference.

[iSore]

The problem with the SE is cheap crap dampers. I'd retain the standard springs but replace the dampers with Bilsteins such as a B6. Or, you could add a set of Eibach springs whilst it's all apart. For anti roll bars, find a breaker who's dismantling a damaged M Spport model.

[f1nn]

RobM77 said:

That applies in most cases, where the car plus upgrades usually cost significantly more than that better car would in the first place. In this case though, the ED is such a bargain that this may well be the best route. Plus, it's a car I've known since new and I know it's been looked after unbelievably well.

Okay, so let's look at this, by the time you've replaced:

Front Springs
Front Dampers
Rear Springs
Rear Dampers
An Assortment of bushes
New Wheels
New Tyres
Possibly Front Seats as an above poster has said, so then most likely a full interior
Increased cost of insurance as a modified car
Possibly decreased resale value

Is it still looking like a bargain?

[RobM77]

f1nn said:

RobM77 said:

That applies in most cases, where the car plus upgrades usually cost significantly more than that better car would in the first place. In this case though, the ED is such a bargain that this may well be the best route. Plus, it's a car I've known since new and I know it's been looked after unbelievably well.

Okay, so let's look at this, by the time you've replaced:

Front Springs
Front Dampers
Rear Springs
Rear Dampers
An Assortment of bushes
New Wheels
New Tyres
Possibly Front Seats as an above poster has said, so then most likely a full interior
Increased cost of insurance as a modified car
Possibly decreased resale value

Is it still looking like a bargain?

I never said it was a bargain by the time I've finished I would like to work out what the car would cost plus these upgrades; obviously if it's less then that's great, but I think that's unlikely. However, if it's only a thousand or two more than an equivalent M sport would be then that's also good for me, because I know the car's history so well, and the extra mpg would probably pay for that difference in the time I own the car anyway, or at least narrow it. In short I just need to crunch the numbers. Resale isn't of interest, due to the mileage when I sell it on and the car's very low value at that time, and obviously neither are the seats or a different interior!

[RobM77]

Thank you for the helpful answers That's given me some starting points.

I should have said actually that I'm such a stickler for handling that I usually replace dampers and bushes every 50-100k anyway, so the extra cost isn't necessarily that great, because I'd be doing it anyway. However, if the M Sport is designed for bigger wheels then yes, that could get expense.

[Trabi601]

Remember, EDs are down on power, have (I recall) longer gearing and poverty spec. interiors.

They're not significantly more economical than an SE / MSport, so you're unlikely to recover the cost of making the car into something it isn't.

A few colleagues have F30 320d EDs as they liked the tax saving. After a ride in a proper spec. car, they all wish they'd ignored the saving and ordered a decent car.

[f1nn]

ED's came on 16" wheels, so if you are keen on replicating the M sport, then realistically you'll be putting it on a set of staggered 18's, which is not the end of the world as there are loads about second hand, but it is an extra expense.

[RobM77]

Just as an update, I've done some more digging and discovered that apparently my 320d SE runs on stiffer rear springs because it has a factory fit towbar, so this would obviously affect the handling in the way I experienced when trying both cars. I get the ED this Friday, so as suggested above, my first step is to check the tyre pressures and get a full geo done. If that fails, I'm going to look into suspension mods. Now that I've started to research E90 M Sport further, I don't like the idea of fatter rear tyres on a car with such little power. As such, I'll make my first step beyond geo and tyre pressures to be establishing whether the ED runs the same springs as the SE, and if it does then I could simply fit the slightly stiffer rear springs, which given that I also tow a 1400kg car trailer regularly, would be a good thing for that too.

[RobM77]

Just an update. Birds suspension fitted, rather than factory M Sport, and I'm very pleased indeed. Short write up here:

https://www.pistonheads.com/gassing/topic.asp?h=0&...