Lowering a 964 with Bilstein & HR
03-29-2018, 07:21 PM
#31
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MB,
After I installed the B6 and H&R springs I did my first wheel alignment, I set the car to RS specs. As it was my first DIY wheel alignment I had our local race specialist check my work. So only small adjustments but still at RS alignment toe, cambers, & caster. I haven't done a weight balance yet. I am lining up to do a complete bushing replacement over winter (yes, "winter is coming" down under). So post the bushing install I will do another alignment, and then a balance.
Back to the mushiness you mention, I know what you mean, and there was some float on the front as well, however, the sway bar has eliminated both. It is well worth the investment to upgrade to a 21mm ARB. I am sure in the USA finding a 21mm bar is lot easier to source than from NZ. I ended up buying a new bar from FVD Europe. Don't ask me about the freight cost! I know some folk have gone to H&R and RUF bars, but I wasn't convinced about 24mm to 26mm bars. I think the bigger bars are more for full time race / track set up. And of course a thicker bars doesn't nessceraly mean stiffer: e.g material, solid or hollow etc.
After I installed the B6 and H&R springs I did my first wheel alignment, I set the car to RS specs. As it was my first DIY wheel alignment I had our local race specialist check my work. So only small adjustments but still at RS alignment toe, cambers, & caster. I haven't done a weight balance yet. I am lining up to do a complete bushing replacement over winter (yes, "winter is coming" down under). So post the bushing install I will do another alignment, and then a balance.
Back to the mushiness you mention, I know what you mean, and there was some float on the front as well, however, the sway bar has eliminated both. It is well worth the investment to upgrade to a 21mm ARB. I am sure in the USA finding a 21mm bar is lot easier to source than from NZ. I ended up buying a new bar from FVD Europe. Don't ask me about the freight cost! I know some folk have gone to H&R and RUF bars, but I wasn't convinced about 24mm to 26mm bars. I think the bigger bars are more for full time race / track set up. And of course a thicker bars doesn't nessceraly mean stiffer: e.g material, solid or hollow etc.
03-29-2018, 08:38 PM
#32
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I am getting ready to install on my Cab, currently have the rear shocks, springs and waiting on the fronts which are on back order. Going to order OE front top mounts and spacers, rear mounts, bump stops and protective tubes when the front shocks ship. A few more questions for the experts.
Is there a locking collar for the adjusting nuts?
Is a spanner wrench required to adjust the ride height once they are on the car?
Do the front shocks have a built in bump stop?
Is there a locking collar for the adjusting nuts?
Is a spanner wrench required to adjust the ride height once they are on the car?
Do the front shocks have a built in bump stop?
Last edited by Ralph3.; 03-29-2018 at 08:38 PM. Reason: gramar
03-29-2018, 08:45 PM
#33
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I am getting ready to install on my Cab, currently have the rear shocks, springs and waiting on the fronts which are on back order. Going to order OE front top mounts and spacers, rear mounts, bump stops and protective tubes when the front shocks ship. A few more questions for the experts.
Is there a locking collar for the adjusting nuts?
Is a spanner wrench required to adjust the ride height once they are on the car?
Do the front shocks have a built in bump stop?
Is there a locking collar for the adjusting nuts?
Is a spanner wrench required to adjust the ride height once they are on the car?
Do the front shocks have a built in bump stop?
1)The Bilstein B6 have a locking collar on the front, but not the rear.
2) You ideally need two C spanners to adjust and lock the struts.
3) Yes the front struts have a built in bump stop.
Have you ordered new top gaskets for the front too?
S
03-29-2018, 08:55 PM
#34
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Gaskets are on my list, so far I am around $1K for all the small OE parts in addition to shocks and springs. Did you replace the bolts that mount the struts to knuckles?
03-29-2018, 09:18 PM
#35
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03-29-2018, 11:27 PM
#36
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Yeah my shocks and springs very quickly escalated to about $6500 worth of suspension updates. The sweating steering rack didn’t help matters 
But I’m happy with the results and she should be good to go for another 25 years.
But I’m happy with the results and she should be good to go for another 25 years.
Last edited by Marine Blue; 03-30-2018 at 12:43 PM.
03-30-2018, 10:25 AM
#37
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I understand that sway bars will help improve turn in and reduce sway or lean. Is this what you are talking about? Sways are an aid to help fine tune and shouldn't be used IMO to fix issues with springs and shocks. If you go with stiffer shocks and springs you will find you need less sway bar.
03-30-2018, 12:41 PM
#38
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I understand that sway bars will help improve turn in and reduce sway or lean. Is this what you are talking about? Sways are an aid to help fine tune and shouldn't be used IMO to fix issues with springs and shocks. If you go with stiffer shocks and springs you will find you need less sway bar.
03-30-2018, 02:42 PM
#39
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03-30-2018, 02:59 PM
#40
03-30-2018, 03:14 PM
#41
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What I’m observing is a very slight lean/looseness on the initial turn in before the car plants itself and sticks hard through a corner. I still attribute some of it to the 16” Conti tires which I know will have some roll associated with them on that initial turn in but it sounds to me like the rear sway may also be a component in this. Once the car settles (which literally isn’t even a second) it is very planted and I can push very hard through tight turns or sweepers. It’s surprising how much grip is available once you figure out the handling characteristics of these cars.
It is about objective at the end of the day. Mine is a good handling car, but predomintaely stock in and out. Hence I am sticking with D90s, flags, and the original look.
03-30-2018, 03:19 PM
#42
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What I’m observing is a very slight lean/looseness on the initial turn in before the car plants itself and sticks hard through a corner. I still attribute some of it to the 16” Conti tires which I know will have some roll associated with them on that initial turn in but it sounds to me like the rear sway may also be a component in this. Once the car settles (which literally isn’t even a second) it is very planted and I can push very hard through tight turns or sweepers. It’s surprising how much grip is available once you figure out the handling characteristics of these cars.
03-30-2018, 05:29 PM
#43
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MB, Cobalt's post triggered my mind that your car is a C2 while mine is a C4. The stock ARB in a C4 '89 is 18mm. The C4 has an inherent characteristic to understeer. My new suspension setup certainly improved the handling. I upgraded the ARB to 21mm to fine tune out the push / understeer in deep corners. The C2 will either have a 21mm or 20mm ARB on the rear depending on its year ('90 21mm). A quick check with a gauge will reveal the size. What you are describing may be oversteer and I have read that C2 owners do better with a 18mm ARB in the rear! Back in the day, owners use to trade (says some older threads). The tyres you have being a performance road tyre will have a moderate slip (angle) but good in my view for mostly our spirited driving.
It is about objective at the end of the day. Mine is a good handling car, but predomintaely stock in and out. Hence I am sticking with D90s, flags, and the original look.
It is about objective at the end of the day. Mine is a good handling car, but predomintaely stock in and out. Hence I am sticking with D90s, flags, and the original look.
so i am going with a 22 mm Eibach bar in the rear of mine and may remove the front one entirely to get the car to turn in better
03-30-2018, 07:11 PM
#44
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Yes, the K model ‘89 is an Unicorn. I mostly find it is best to take out what you intend working on before ordering parts.
04-01-2018, 02:04 PM
#45
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I forgot are you running the equivalent of greens or reds? Could be a number of factors. If running greens it is partially the soft spring and being progressive they will transition from soft to stiff in cornering. I found this with the early Eibach's and greens not so much with the reds. Also I hate to say this cabs and targas have some body flex. I have driven targas with a truss setup behind the rear seats that ties into the seat belt and harness type bar that eliminated this using reds and HD's. There is also slop in the steering rack that can be reduced with stiffer rack bushings and the 993 steering rack brace. We can go on from there. It took me several setups before I found what I like but mine is a weekend car and not a DD. So it is a bit of a compromise.
The car feels very tight, doesn’t rattle and honestly I don’t really feel body flex but I haven’t driven a coupe back to back on twisty roads so I can’t say for certain that the chassis isn’t playing a role.
I do think that the tires are playing a bigger role in this, I recall when I had the 17” wheels/tires the car felt more response even before the suspension upgrades and 10 year old tires. I will be switching to 17” wheels later this year or early next year so I’ll report back.
Still curious if there’s anything else I’m missing.