Coilovers

[tomson]

I'm almost ready to purchase a set of these, I will probably buy the Gaz ones from this thread,

http://www.e30zone.net/modules.php?name ... ic&t=91570

What I would like to know is what spring rates would suit the car best as it has a S38 M5 engine fitted which is obviously a lot heavier than the M20!

Is there a calculation that can be done to work out what is best or something like that ? ?

[UweM3]

if you know your current spring rate you can measure by how much it compresses the spring when taking off the jack. That will give you at least some sort of idea. Do you know what I mean? (Just asking cos I know I am bad explaining stuff)

[SteMarsden]

I have ordered the same set for my PBMW car.

GAZ supply nominal springs for the M40 and M20 engined cars (IIRC its 500/300lb for the 318), but Im sure that they will be able to help. Esp if you can give them idea of the cars weight and balance to compare to a PBMW car.
The beauty is that if your not happy with the set up, you can get replacement springs for about £50!

Hope your not in a rush though, ordered mine on 20th December and am still waiting for them to build some fronts..... All other parts were ex-stock.

[tomson]

Uwe - no I dont really understand, sorry !

Ste - I'm not in a massive rush, Feb time suits me I just want to know what will be best to order as I know f**k all about coilovers. I guess if I provide Gaz with the weight of the S38 and the M20 say, they would be able to work out the differenc and which spring rates would be best ? ?

[Jhonno]

Do you know the current spring rates?

How far does the car compress the springs from the point of wheel contacting the ground

[tomson]

Do you know the current spring rates?

How far does the car compress the springs from the point of wheel contacting the ground

No, it has some lowering springs of some description - probably Eurocar parts specials!

Karan said when the lump was in his car it handled like a pig - the Hartge suspension he had was crap and coilovers were the only way to go......

I could just go for 325i ones but I assume because the S38 is much heavier than the M20 it might still be a crap handler and the coil overs a waste of money........

[Theo]

You'd be best of spending a little extra and going to a place who will corner weight the car and get you proper spring rates. These people sell the kit and offer the service http://www.balancemotorsport.co.uk/site ... nsion.html

[tomson]

corner weight the car

Forgive my ignorance but what is this exactly?

(I can probably guess but better to hear from someone that knows!)

[Jhonno]

weigh each corner of the car, see how much force (weight) is acting through each corner, then raise/lower the car to even it up and effect weight distribution etc

[shorty73]

When you corner weight it, you want the diagonal weights to be equal or near as you can.If you want to work out what your corner weight should be it goes like this;

work out total car weight (with Driver)

work out front and rear %'s

work out L and R %'s

convert %'s to decimal ie 40% = 0.4

Then do the maths.

LF = total mass x F% x L%
RF= total mass x F% xR%
LR= total mass x R% x L%
RR=total mass x R% x R%

[Theo]

Give them a Ring or email Tom, they will talk you through what they can do.

[SteMarsden]

Tomson,
Just FYI.... GAZ called me today to tell me that they are dispatching my coilovers tomorrow as they had built a couple of sets up now....
Ste.

[tomson]

You'd be best of spending a little extra and going to a place who will corner weight the car and get you proper spring rates. These people sell the kit and offer the service http://www.balancemotorsport.co.uk/site ... nsion.html

Looks good. I have looked for somewhere closer to me to do this kind of thing but google only shows balancemotorsport for some reason
Anyone know of anywhere that does this kind of thing in the Southwest?

[tomson]

Tomson,
Just FYI.... GAZ called me today to tell me that they are dispatching my coilovers tomorrow as they had built a couple of sets up now....
Ste.

Sweet, got any pics ?

[SteMarsden]

Tomson,
I hav'nt taken any pics yet but will get some tomorrow, looks fantastic mate.... Been busy painting the cage and sealing up the sunroof but will try and post some pics asap or on the new site.

[BadDave]

Rears




Alloy top mounts



HTH

[rosscoe]

wat was the spring rates on these bad boys dave

[BadDave]

wat was the spring rates on these bad boys dave

350lb fronts and 225lb rears on the 316 Tam
These are for road use though
Fronts will be changed to 450lb when the 6 pot goes in

[SteMarsden]

Mine are for the PBMWC (318) and are 500lb/275lb...

[Reeeedish]

GAZ coilovers are awesome.
I use these on my E30 Race Car and can't rate them highly enough!
I have 600lb fronts and 300lb rears. Very stiff indeed (M20 engine and full weld in Custom Cage picking up on all 4 strut turrets) and using R888 tyres.

Tom, how's it going mate? Haven't spoke for a while!
If your stuck for somewhere to get the GAZ coilovers, we now offer them:
www.Redish-Motorsport.com/Gaz.html

We only sell the GAZ Gold (GGA) coilovers which are height AND damping/rebound adjustable and are designed for serious track usage / Race applications.
You can get Road applications that are just height adjustable and NOT damping/rebound adjustable, these are called GAZ (GHA).

GAZ retail is currently £949.50 for the Gold (GGA) kits.
We are offering them at just £825.
(E30 coilovers require a donor set, if you can't supply a set or live without your originals for up to 3 weeks then please do ask as we can provide donors to be sent to GAZ).

They are proving very popular indeed. We sold 2 sets for E36 M3 customers last week alone.

I have to speak to Dave on Monday anyway so I can certainly ask if he has any recomendations for your S38 application.

James

[Jhonno]

Gaz seem to be very much a love or hate coilover..

I've heard the shocks aren't great. At the same time, i've heard plenty of people inc racers satisfied with them..

[JT1]

I have just ordered a set of GAZ coilovers for my road going track day 325 sport, after to speaking to GAZ they recommended 500 - 550 front springs and 225 rear springs, the lads who race are using 600 - 650 fronts and 275 rears, hope this helps

[tomson]

Not really as I'm using a S38 which is much heavier than an M20.

I think I will be taking the turd to balance motorsport when the time is right....

[JimmyC]

There is an e30zone GAZ deal somewhere on here- cant find the thread, it exists as I sorted it

85% of the PBMW field run them and have for several years, all with very positive feedback

[bss325i]

I'm thining about these now as well. I'm in the same boat as Tomson though as i have an S50B30 so not sure what spring rates to use either.

Is a road/trackday car as well by the way, more road than track though!

[fastdiablo]

I'm watching this thread with interest, I have a similar problem with an m30b35 conversion . . .

I just bought (but not yet fitted) a set of Bilstein B8's with a set of -30mm springs. Now, after reading this thread, especialy the bit about how Karran is selling his setup because his hartge sorted B8's didnt do the job, I'm wondering if the B8's I bought will do the job and if not, what are my best options ? ? ? . . . .

[bss325i]

I'm watching this thread with interest, I have a similar problem with an m30b35 conversion . . .

I just bought (but not yet fitted) a set of Bilstein B8's with a set of -30mm springs. Now, after reading this thread, especialy the bit about how Karran is selling his setup because his hartge sorted B8's didnt do the job, I'm wondering if the B8's I bought will do the job and if not, what are my best options ? ? ? . . . .

Depends on what your going to use the car for. I currently have B8's, H&R 35mm springs and H&R roll bars and its ok but it could be better. I have an S50B30 by the way which is heavier than an M20.

[fastdiablo]

Its going to be my main workhorse, all duties from commuting through pulling a bike trailer to spirited driving or the occasional trackday maybe even a trip to the ring (have been twice on the bike )


According to bimmerforum's spec sheet the m30 is 19kgs lighter than an s50 but still 26kgs heavier than the std m20b25 that came out . . .

That quite a bit extra to control ! . . .

[bss325i]

Its going to be my main workhorse, all duties from commuting through pulling a bike trailer to spirited driving or the occasional trackday maybe even a trip to the ring (have been twice on the bike )


According to bimmerforum's spec sheet the m30 is 19kgs lighter than an s50 but still 26kgs heavier than the std m20b25 that came out . . .

That quite a bit extra to control ! . . .

So an S50 is 45kg more than an M20?!

[fastdiablo]

Ooops, can't count

m20 117kgs
............................26kgs differance
m30 143kgs
..............................9kgs differance
s50 152kgs
............................35kgs more than m20



http://www.bimmerforums.com/engine_faq/

[bss325i]

Nice one.

[fastdiablo]

Ooops, can't count

m20 117kgs
............................26kgs differance
m30 143kgs
..............................9kgs differance
s50 152kgs
............................35kgs more than m20



http://www.bimmerforums.com/engine_faq/

Just to add,

the m40 is 81 kgs ! . . .

....36 kgs less than m20

....62 kgs less than m30

....71 kgs less than s50

the M42 is 100kgs.