Bilstein shock comparison

[Timothy B.]

I have been researching shocks for my C2 small block car, and in doing so called Bilstein to discuss their options. Their tech was very helpful and provided some specs on their HD and Sport variants that are available for Corvettes. He said that the Sport shocks are really quite firm, and are generally used for folks autocrossing their cars. For weekend drivers, the HD shocks are recommended. I asked what the actual specs are and this is what he gave me:

At a shock speed of 20 in/sec, all values in newtons (metric resistance force):

HD shocks front:

Rebound 1991
compression 1018

Sport shocks front:

Reb 2870
comp 1585

HD shocks rear:

reb 1580
comp 970

Sport shocks rear:

reb 2795
comp 995

The tech said that it is very tough to compare one brand to another using specs since they all measure them at different conditions and speed. Some quote in US units (lbs force) and some in newtons (metric). The tech couldn't tell me how this data compares to the shocks I have on the car now, which are KYB GR-2's. I thought this info might be useful to others...

[Duke W.]

Re: Bilstein shock comparison

Good info! I would recommend the Sport settings for F-40/41 and FE7 suspensions. The spring rates on these suspensions are double the base suspension spring rates and need the extra rebound damping to control rebound.

These HD suspensions were meant for racing not street use. If they have too little damping they will be stiff and bouncy. With correct damping they will be stiff and firm.

Duke

[Duke W.]

Re: Bilstein shock comparison

Good info! I would recommend the Sport settings for F-40/41 and FE7 suspensions. The spring rates on these suspensions are double the base suspension spring rates and need the extra rebound damping to control rebound.

These HD suspensions were meant for racing not street use. If they have too little damping they will be stiff and bouncy. With correct damping they will be stiff and firm.

Duke

[Timothy B.]

KYB shock comparison

Well, I called KYB and asked for raw shock data and was able to come up with a list that I can post here for comparison. Note that the quoted data had to be converted from metric to US units, and the data is quoted at 0.6 meters/sec which is about 23 inches/sec. That is as close as I can get to the 20 in/sec data from Bilstein. This would mean that the KYB data is slightly higher than it would be at the same speed as the Bilstein data. Since I don't have the actual curves I can't tell how much higher.

The GR-2 are twin tube shocks with low pressure gas, the Gas-Adjust are monotube high pressure gas shocks. All of the Bilstein shocks are monotube high pressure gas.

At a shock speed of ~23 in/sec, all units in newtons (converted from Kg force):

GR-2 shocks front (pn 343127):

Rebound 2304
compression 686

Gas-Adjust shocks front (pn KG4550):

Reb 2108
comp 883

GR-2 shocks rear (pn 343218):

reb 2207
comp 883

Gas-Adjust shocks rear (KG5501):

reb 2402
comp ? (I missed this one, probably is around 1128 newtons)

[Timothy B.]

KYB shock comparison

Well, I called KYB and asked for raw shock data and was able to come up with a list that I can post here for comparison. Note that the quoted data had to be converted from metric to US units, and the data is quoted at 0.6 meters/sec which is about 23 inches/sec. That is as close as I can get to the 20 in/sec data from Bilstein. This would mean that the KYB data is slightly higher than it would be at the same speed as the Bilstein data. Since I don't have the actual curves I can't tell how much higher.

The GR-2 are twin tube shocks with low pressure gas, the Gas-Adjust are monotube high pressure gas shocks. All of the Bilstein shocks are monotube high pressure gas.

At a shock speed of ~23 in/sec, all units in newtons (converted from Kg force):

GR-2 shocks front (pn 343127):

Rebound 2304
compression 686

Gas-Adjust shocks front (pn KG4550):

Reb 2108
comp 883

GR-2 shocks rear (pn 343218):

reb 2207
comp 883

Gas-Adjust shocks rear (KG5501):

reb 2402
comp ? (I missed this one, probably is around 1128 newtons)