E55 Bulldog

Does anyone know if the P30 suspension is lower then the non-P30 cars. I know there has been talk about it but does anyone have actual confirmation that this is true.

Thanks guys.

I am Jeff

It has been confirmed that P30's are lower than non P30's.

E55 Bulldog

Do we know by how much? 20mm ?

Im trying to do some math on 20" wheels and tires based off another forum members information on his non-P30.

I don't want to f' myself and buy a set that rubs like hell.

noodleman

it's definitely not 20mm. it sits higher than H&R springs which lowers the car by 20mm from stock iirc.

From just looking, i honestly cannot tell the difference in ride height from a P30 to a non-p30 car.

izzyAMG

I know its hard to tell but in person white (p30) is defintely lower but not by much.
Did you guys notice the bulges on the hood are different in the 2012's but that's another thread.

rory breaker

Left is 2012 P31, right is 2009 P30, if it helps.

sjhugh

Mate the difference between the two suspension packages probably doesn’t really matter.

What you could do is measure off half the diameter of the tyre size you are interested in onto a piece of string and mark the appropriate length. Then place one end of the string at the centre of the wheel hub and swing the other end over the top in an arc. This will show you approximately where the tyre will be in relation to your fender in elevated view.

The car needs to be on level ground, you need to take into account the additional compression of the springs when you have the weight of passengers in the car, the compression of the springs that will be caused by the up and down movement of the suspension when negotiating dips in the road and cornering etc, and remember the outer edges of the tyres are rounded so they will not be at exactly the same dimension as the centre of the tread.

If you add to this any info on tyre/rim width and rim offsets you will get a reasonable indication of where the tyre will place. If it’s touch and go, I’d use the rule that it will rub.

.

jim07

This question has been asked several times with no real answer. So I just measured my 2009 with P30 at 26 7/8" front and rear from the ground to the bottom edge of the wheel well (painted fender) dead center through the rim. That is with 50% wear on micheln pilot sports with 3/4 tank of gas. So someone measure a non P30 and we will have an answer.

bhamg

With all due respect you probably won't, at least in any definitive fashion. In my personal experience three of us who installed Dinan Stage 1 suspensions (springs and shocks) on our otherwise stock M5 suspensions all experienced differing results (measured independent of wheel and tire considerations). IIRC the max difference between vehicles measured same-corner to same-corner was about 8mm.

jim07

Well if we get two or three P30s and two or three non P30 we will at least have an average difference.

Mikegpr03

Guys I have a P30 car and the height is the pretty much the same. I can tell you that the ride is very stiff. The shocks are valved very aggressively. Anyone in Miami with a non P30 car around so we can put this myth to rest. ???

jim07

Would a couple non P30 cars take the measurements? Be nice to know.

bhamg

I'll stick with what I've been told by someone who should know what he's talking about - P30 is 10mm lower than non-P30.

Mikegpr03

Well if anyone wants to meet up see we can take some measurements and see if this actually the case.

jim07

All we need is a non P30 owner with a tape measure. Lets get some samples. Its not that hard!!! So if 10mm (1/2") taller for the non P30s is true it should be about 26 1/2 from the ground through the center of the rim to the bottom edge of the painted fender well. I know there are other variable but 10mm should show up as the average difference if we can get a few samples of each.

Mikegpr03

Let's do it ! I'll get some pics and numbers today and post

jim07

front on cold tires 2009 P30




Rear 50 degrees - cold tires

My first measurement was off ----too many beers.