E24 Suspension Upgrade

[GregNZ 3]

I have started exploring options for a suspension upgrade to my 1982 635.

The car is a car to be driven and enjoyed not a show car but also deserves to be beautiful :).

I would like to lower the car a little to reduce the wheel arch gap and stiffen up a little. Could be say 20 - 35mm.

I generally like a firm buttoned down ride but i am also concious that our roads are usually pretty rough and compromise is necessary.

The car will be a street car used for just the occassional track laps at Hampton for fun and my driving pleasure but will not be raced per se.

Options I am aware of;

1) Considered coilovers but most recommendations I received were, if not racing, stay with conventional struts / shocks

2) Billi B8s with H&R sport springs - lowers @ 30mm I think. Will this create negative camber issues and will the ride be firm but still acceptable for cruising? 

3) Billi B6s with ... springs. Not sure whether B6 is compatible with lower springs and if so what effect is?

I would welcome feedback from anyone with experience on the above or other alternatives.

Thanks guys

Greg

 

 

[Olaf 3309]

why not Koni Yellows, as a matter of interest?

[kiwi535 538]

as a matter of reference i had a E34 535 "is" They were fitted with motorsport suspension and i found that to be a nice compromise between ride and handling.If you could replicate that setting in an E24 i think thats where you should aim

Edited May 6, 2019 by kiwi535

[Eagle 1661]

2 hours ago, GregNZ said:

2) Billi B8s with H&R sport springs - lowers @ 30mm I think. Will this create negative camber issues and will the ride be firm but still acceptable for cruising? 

3) Billi B6s with ... springs. Not sure whether B6 is compatible with lower springs and if so what effect is?

You can run B6 with lowering spring but its not optimal so more risk of running them out of their range, though 30mm may possibly be doable. I ran 40mm H&R with B6's in my old E30 before switching to B8's and having them re-valved at the same time, ride quality and both and rebound control were noticeably better after that. 

Another option could be to try H&R OE sport springs with B6's to try and recreate a stock sport package. Ive always felt BMW sports setups were good for the average street car with decent rubber and didn't ruin ride quality.

1 hour ago, Olaf said:

why not Koni Yellows, as a matter of interest?

I like them but they are expensive and a pita if you want to change rear settings.

1 hour ago, kiwi535 said:

as a matter of reference i had a E34 535 "is" They were fitted with motorsport suspension and i found that to be a nice compromise between ride and handling.If you could replicate that setting in an E24 i think thats where you should aim

Boge\Sachs sport dampeners, not sure they would make them for E24 given its quite old.

Edited May 6, 2019 by Eagle

[hotwire 352]

^^^^  got a set of Factory sport option Billy's for the E12 a couple of years back out of BMW AG

[Kodachrome 150]

5 hours ago, Olaf said:

why not Koni Yellows, as a matter of interest?

I think they are long out of production (assuming same as E28 if later E24 being discussed, not clear as the change is was in 82). To the OP, FWIW, I just ordered the B6's plus the Ireland Engineering springs. Granted B6's are not usually for usage with lowering springs, but internet forum folklore suggests IE springs are actually not any lower than stock (some people claimed they were higher than 20yr+ fatigued originals). 

[GregNZ 3]

Thanks guys for comments to date.

By way of clarification the 635 is late '82 ie on the e28 platform

I would have considered Koni yellows but hit a blank trying to find the correct fit. I think Kodachrome may be right and they are no longer an option.

Kiwi535 - appreciate your thought there - I guess that would be the M635 equivalent which I believe is @ 20 - 25mm lower and a little stiffer than the stock 635. I am not sure how I could confidently replicate that without using OE equipment which I expect might be considerably more than the Billi / H&R cost??

Regarding the springs - lowering @ 25mm would probably be @ ideal and might work with B6s - has anyone tried something @ that and if so using which springs and with what result? Based on my reading I kept coming back to H&R as the 'performance' brand of choice but that may be only because they are better at marketing  

And then if going that far am I better running to the B8s with H&R sport albeit 30 - 35mm lower than stock - if only we could try before we buy 

Is anyone running an e24 or e28 with Billi / H&R or similar ?

Sorry I accidentally got this thread in the wrong forum - newbie!!

 Thanks again

[sdotmac 0]

needed to read this 6 months ago. Have just installed B6 + H&R spings (~30mm drop) on my 1984 635 and dont recommend - nice height but the B6s are too long. The rear springs are in the middle setting and have a smidge of useful travel but the fronts are pretty much on the bumpstops.   Definitely saving for B8s now, but also going to do a LOT more homework first. 

On 5/6/2019 at 8:25 PM, Eagle said:

You can run B6 with lowering spring but its not optimal so more risk of running them out of their range, though 30mm may possibly be doable. I ran 40mm H&R with B6's in my old E30 before switching to B8's and having them re-valved at the same time, ride quality and both and rebound control were noticeably better after that. 

Another option could be to try H&R OE sport springs with B6's to try and recreate a stock sport package. Ive always felt BMW sports setups were good for the average street car with decent rubber and didn't ruin ride quality.

I like them but they are expensive and a pita if you want to change rear settings.

Boge\Sachs sport dampeners, not sure they would make them for E24 given its quite old.

@Eagle  Your thoughts on standard B8 stiffness/ where did you get them revalved and to what sort of setting?? Agree on aiming for a sport package - I was shooting for ballpark to my old M-Sport E36 ride with the B6's, but they feel somewhere in between that and standard (to me . 

Edited June 7, 2019 by sdotmac
added photo

[Eagle 1661]

Believe it was through Autolign, at the time i just specified what springs i had and just wanted the setup to be a bit more livable on the road.

I never used B8's are std, i got them revalved after removing the B6's that i bought instead of B8's. H&R springs aren't known for great for ride quality either. E24 should ride better than an E30 either way. 

[Contrails 316]

I am running option 2 in my E28.  Love em.  Firm and handles very well especially with RE003. 

[Bennyboy 199]

On 5/6/2019 at 5:59 PM, GregNZ said:

I have started exploring options for a suspension upgrade to my 1982 635.

The car is a car to be driven and enjoyed not a show car but also deserves to be beautiful :).

I would like to lower the car a little to reduce the wheel arch gap and stiffen up a little. Could be say 20 - 35mm.

I generally like a firm buttoned down ride but i am also concious that our roads are usually pretty rough and compromise is necessary.

The car will be a street car used for just the occassional track laps at Hampton for fun and my driving pleasure but will not be raced per se.

Options I am aware of;

1) Considered coilovers but most recommendations I received were, if not racing, stay with conventional struts / shocks

2) Billi B8s with H&R sport springs - lowers @ 30mm I think. Will this create negative camber issues and will the ride be firm but still acceptable for cruising? 

3) Billi B6s with ... springs. Not sure whether B6 is compatible with lower springs and if so what effect is?

I would welcome feedback from anyone with experience on the above or other alternatives.

Thanks guys

Greg

 

 

Greg, can I ask what setup you ended up with in the end?

 

im in a similar position and it’d be good to know what direction you opted for