billly sport vs. HD?

[lucky7]

ive been doing some reading, but havnt found what im looking for. what exactly is the difference? i was initially planning on billy sports w/ EI race II springs. i dont really care about comfort. i want it to handle. and i want it to handle as best i can, on the cheap. are the HD just more sporty than the sports? thanks guys.

[Jordan325iC]

HD shocks are if you are NOT lowering the car.

Sport shocks are if you are planning to lower the car.


Since I can only assume that the race springs you are buying are going to lower the car, I suggest you get the sport shocks.

[Sam Cogley]

HD are for stock ride height, Sport are for lowered springs (Bilstein's website lists the Sports as OK for M3 springs).

Nothing that a quick search wouldn't have revealed. ;)

[lucky7]

werd? thats all i needed to know. thank you sir!

[Hellabad]

The Bilstein Sport and the HD are THE SAME STIFFNESS. The same damping inside, the Sport is not firmer.

The only difference is that the Sports, front and rear, have less droop when you jack the car up. This makes it so that old school springs did not come loose when you jacked up the car for a TUV inspection in Germany in 1988.

There is a -slight- difference in feel, because the front is so short you can get droop limited, but not very noticeable anyway.

The big misconception about Bilstein Sports, for any car including e30, is that they are "shorter". Well, they are shorter.......when they are sitting on a shelf at the parts store. Once you install them on a car, they have the exact same amount of "downward" or "bump" travel as the Bilstein HD.

That Bilstein is an older design, like Cyndi Lauper.

Click here for Cyndi Lauper 1988

Cyndi Lauper 1988


Cyndi Lauper 2008


Jay Ground Control

[alpinaclone]

I know I have billy sports in the back because I bought them new. The front struts however, I bought used in Germany off of a guy that said they were some weird group 2 or something or other shocks. They are stiff as hell and the body is inverted, i.e. the shaft is huge. Do all sports have a shaft like this, or was the guy not full of shit and they are something special? If so is there anyway to tell exactly what I have?

Sorry for the thread jack.

[Hellabad]

I know I have billy sports in the back because I bought them new. The front struts however, I bought used in Germany off of a guy that said they were some weird group 2 or something or other shocks. They are stiff as hell and the body is inverted, i.e. the shaft is huge. Do all sports have a shaft like this,

All the BMW e30 struts are inverted fat shaft. Some of the VW and e36 stuff is not made in Germany and is sealed regular twin tube.

If so is there anyway to tell exactly what I have?

Write down all the part numbers and I can translate. Every single number you can find, because they might be revalved.


Jay

[alpinaclone]

All the BMW e30 struts are inverted fat shaft. Some of the VW and e36 stuff is not made in Germany and is sealed regular twin tube.



Write down all the part numbers and I can translate. Every single number you can find, because they might be revalved.


Jay

Cool, I really appreciate the help. I will be pulling the struts apart this weekend and will make note of the numbers and hit you back.

edit: The Cyndi Lauper reference is funny, but where the hell does one come up with such a thing?

[funcrew]

The Bilstein Sport and the HD are THE SAME STIFFNESS. The same damping inside, the Sport is not firmer.

The only difference is that the Sports, front and rear, have less droop when you jack the car up. This makes it so that old school springs did not come loose when you jacked up the car for a TUV inspection in Germany in 1988.

There is a -slight- difference in feel, because the front is so short you can get droop limited, but not very noticeable anyway.

The big misconception about Bilstein Sports, for any car including e30, is that they are "shorter". Well, they are shorter.......when they are sitting on a shelf at the parts store. Once you install them on a car, they have the exact same amount of "downward" or "bump" travel as the Bilstein HD.

That Bilstein is an older design, like Cyndi Lauper.

Click here for Cyndi Lauper 1988

Cyndi Lauper 1988


Cyndi Lauper 2008


Jay Ground Control

I think she's still hot, but I'm REALLY, REALLY old. Check with me in 2018.

[e34john]

The Bilstein Sport and the HD are THE SAME STIFFNESS. The same damping inside, the Sport is not firmer.

The only difference is that the Sports, front and rear, have less droop when you jack the car up. This makes it so that old school springs did not come loose when you jacked up the car for a TUV inspection in Germany in 1988.

There is a -slight- difference in feel, because the front is so short you can get droop limited, but not very noticeable anyway.

The big misconception about Bilstein Sports, for any car including e30, is that they are "shorter". Well, they are shorter.......when they are sitting on a shelf at the parts store. Once you install them on a car, they have the exact same amount of "downward" or "bump" travel as the Bilstein HD.

That Bilstein is an older design, like Cyndi Lauper.

Jay Ground Control

So what everyone says about HDs blowing out when used with lowering springs are wrong?

[bimma360]

I had HD's on eibach's for about 100K with no issues EVER up to the point i sold the car with 286K....

[Hellabad]

So what everyone says about HDs blowing out when used with lowering springs are wrong?

On an e30, yes.



Here is info from a 1998 discussion about this, in the early days of the internet on a list called BMW digest. Credit to Pete Read who got it from Bisltein engineers, who won't tell you this anymore.


E30 3 series 325e/es, i/is, M3
(3 series 87-91, 318i thru 86, front has 30mm piston, P30)
rebound / compression force at 52 cm/sec

Newton pound-force
N lbf (0.2248 x N)
------------ ------------------
Front:
P36 0132 Sport 2220/850 499 / 191
(P30 0133 Sport) 2220/850 499 / 191
P36 0136 HD 2220/850 499 / 191
(P30 0128 HD) 2220/850 499 / 191

Rear:
B36 2027 1475 Sport 1650/565 371 / 127
B36 2028 0720 HD 1650/565 371 / 127

I have attached a picture of me pressing on a Bilstein sport next to a Bilstein HD,



plus I have added a picture of Joan Jett.

[smonkbmw]

so the larger diameter tube and piston is for nothing?

[Hellabad]

so the larger diameter tube and piston is for nothing?

No, but I'm only illustrating length here. All 318 are p30, and all 325 are p36. Lengths and damping are the same.

What Im saying is p30 HD is to p30 sport as p36 HD is to p36 Sport. It is just a coincidence (look at the damping numbers in that post) that p30 HD = p36 HD and p30 Sport = p36 Sport.

But that is all I have in my pile to show you a picture of.

[Sam Cogley]

No, but I'm only illustrating length here. All 318 are p30, and all 325 are p36. Lengths and damping are the same.

What Im saying is p30 HD is to p30 sport as p36 HD is to p36 Sport. It is just a coincidence (look at the damping numbers in that post) that p30 HD = p36 HD and p30 Sport = p36 Sport.

But that is all I have in my pile to show you a picture of.

I assume the p30 and p36 have something to do with the early 318 small-diameter struts? I think the M42 318s used the same struts as the 325s - I know my '92 318iC has the larger diameter struts...