H&R Spring Low Speed Compliance

[Ascari1]

Hi, I recently bought a 996.1 running H&R springs over Bilstein B4 dampers. Over 40-50mph the damping is pretty good, but under that it feels like it's running on solid suspension, or at least stuff made of wood.

The dampers are only a few thousand miles old but the springs are older (car is only on 74,000 miles old so they won't be hugely old). Question is, is this a mismatch of a damper expecting to work with a longer spring or are H&R a higher spring rate than something like Eibach or Spax?

Any ideas before I loose my fillings on the drive out of town to the A & B roads we enjoy so much?

Ride height pic for reference

 

[gizlaroc]

Which B4 dampers are they?

Can you see the model on them still?

Maybe someone fitted the M030 dampers? I would try and see the model, especially on the rear, I put b4 m030 dampers on the rear of mine and hated them, swapped them for non m030 dampers and now great.

 

[IMI A]

I'd get yourself a set of quality coilovers they'll be the best upgrade you can do IMO. Lowering springs a compromise for serious driving. They're fine on smooth roads but on UK roads when pressing on could be disastrous especially in the higher powered 911s.

 

[Ascari1]

Which B4 dampers are they?

Can you see the model on them still?

Maybe someone fitted the M030 dampers? I would try and see the model, especially on the rear, I put b4 m030 dampers on the rear of mine and hated them, swapped them for non m030 dampers and now great.

They are the M030 versions, from what I can see. B4 VNE B333 & B335.

Would that be compounding the problem?

 

[Shalmaneser]

I've got new m030 springs and dampers and the ride is firm... I personally found the stock dampers pretty squishy but I've upgraded them on pretty much every decent car I've owned. A lot of people really rate the koni active dampers for these cars, might be with a go.

 

[gizlaroc]

They are the M030 versions, from what I can see. B4 VNE B333 & B335.

Would that be compounding the problem?

I hated then B4 M030 damper on my car, just driving around town, or at slower speeds it was horrible, so crashy.

The fronts were actually OK, but then mine is a C4 and from all my research the is no specific M030 damper for the front, it is the same part for M030 cars or standard.

I swapped the rears for standard Porsche dampers and springs, I forgot, I originally ordered B4 non M030 dampers, but then asked on here if anyone had any rears they were not using after an upgrade. Mainly because I had just spent a couple of grand and didn't want to spend another £500 testing the non M030 B4s in case they didn't sort it.

I have now converted my car to RWD, I am also using standard front dampers and springs.
Overall the car is so, so much better, it is now a joy to hustle down UK back roads, and I will now use it round town too, which I hated before.

I do have a set of H&R springs ready to fit, and I will probably fit them soon, but I will keep the standard dampers or if there is any wear when I get them off I will put on Koni actives.

Dampers make far more difference to springs for comfort, within a certain range of course, but between standard and m030 and Eibach and H&R the dampers will make the most difference.

Think how much the ride changes between PASM cars, or if you have ever driven one with a DSC controller fitted, massive difference and the spring has not changed.


I would start by putting on softer rear dampers for the issue you have.

 

[bananaz]

I once ran H&R springs on standard Porsche dampers.

It was too low and ended up with accelerated shock wear. It looked a million dollars, but didn't improve the car's manners at all.

It was too low, the travel was reduced too much, and it rode on the bump stops in town and over rough roads.

It wasn't the firmness of the H&R springs that caused the issue. It was the large drop that removes too much travel.

You could shorten the bump stops which could give back some compression travel and reduce the filling-removal effect. This would, in turn, possibly create further issues with bottoming out suddenly due to unexpected pot holes, etc.

The Porsche solutions such as M030 are your friend. Expensive coilover solutions are also your friend.

Lowering springs are cheap and cheerful, but not a great long term proposition.

On a Golf, fair enough, but 911s are already low cars out of the box.

 

[911UK]

what about the suspension bushing ? wishbone, top mounts, etc ?

 

[gizlaroc]

One thing worth mentioning is there seems to be some inconsistency with Bilstein dampers.

Some find that they have to compress the spring loads to get them to fit, where as other have found the springs are loose in the damper until on the car.

But then I found my springs loose on my first 996 when it was jacked up, where as this one they seem to be really tight no matter what.


Also, I am surprised about H&R being an issue as they are only 15mm shorter than the M030 springs and slightly firmer. But then, maybe it is the inconsistency with damper lengths that causes these issues?
I tried to find the post where someone was showing the differences in length between Bilstein B4s and even two different oem dampers with the same part number.

Are you sure the shocks were not already past their best?

 

[bananaz]

The Boxster in question has less than 5k miles and was only a year or so old when I put the H&R springs on.

The drop was 'aesthetically nice', but way too large to work with the standard shocks/bump stops.

After several years I bought the genuine Porsche sport suspension from Carnewal and swapped the lot.

Incredible difference - phenomenal on track, but still a tough drive on bad roads.

 

[gizlaroc]

Oh, on a Boxster. Interesting.


My 986 S was far softer riding than my 996, I actually replaced the dampers when I got it because it was far softer than I expected it to be, put on the B4's all round, and to be honest when the old stuff come off they were actually fine still, but I had done all the control arms so thought I might as well put new dampers on when doing those. it was still just as soft when I had finished, tight, but very compliant ride wise.

I could see that shorter springs on that car would be an issue, the would rattle around too if with very little travel. Even the OEM dampers the standard springs had hardly any compression on them at all when off the car or when the car was jacked up.

Looking at pics of Boxsters with H&R springs fitted they look slammed, like the tyre is behind the arch, you don't get that drop on using H&R with the 996.

 

[bananaz]

Same deal with the 981!!!

H&R:


Porsche OEM Sport Suspension


996 with standard 'turbo' suspension:

 

[gizlaroc]

Yeah, all the Boxsters, regardless of gen look seriously low when on H&R, Eibachs etc.

The 4S comes 15mm lower than standard anyway, H&R drop it another 10-15mm.

My C4 on m030 looked the same as that 4S with regards to ride height, nice even gap between tyre and arch all the way round.

I just didn't like the ride that much, not the rear anyway.


Isn't the standard Turbo suspension slightly more compliant than the C4S suspension?

Just having a quick search a few people said they found the C4S firmer than their Turbo.