Hi All,
I have installed a set of ARNOTT GEN III air springs on my 2000 P38 and currently having a custom set of Bilstein shocks made to maximize the extended lengths these bags offer.
The stock Bilstein shocks for the P38 have lengths as follow:
B46-2214 Front: 338mm(13.3”) – 535mm(21”)
B46-2215 Rear: 311mm(12.2”) – 482mm(18.7”)
Looking at using the Bilstein 5150 BF5-A195-H1 360mm(14.2”) – 571mm(22.5”)
This means you have to install a 1” higher bump stop on the front and 2” higher bump stop for the rear to avoid destroying the shock on compression. Using the leverage of the axle geometry gives you 1.5” less articulation on compression in the front and 2.5” less on the rear.
This shock will still not give you maximum extension on the front and if used in the rear will over extend the bag by almost 4”.
So I have called on the Bilstein agent in South Africa who is also one of the best custom system builders for off road racing in SA to make this work for me.
The design so far:
Bilstein 46mm mono tube pressurized gas shock using the bigger new 18mm shaft (awaiting specs and confirmation from Germany) with a shock mounted extended canister. Valve rates are left same as the stock P38 values for now.
Front Collapsed: 338mm(13.3”) same as stock so using the stock length bump stops.
Front Extended: 580mm(23”)
This gives 10” travel, with a bit of safety on the collapsed side it is actually 9” travel which is a little more than Arnott recommend and you can adjust this with spacers at installation.
Rear Collapsed: 311mm(12.2”) same as stock so using the stock length bump stops.
Rear Extended: 526mm(21”)
Due to the rear shock mounted at an angle to the axle travel you get more axle travel than shock travel so this gives almost 12” travel on the axle but with the collapsed safety margin is more like 11” which is a little more than Arnott recommend and you can adjust this with spacers at installation.
A ball park estimate for this once off set is around $1600.
Any comments or suggestions on this welcome please!
CRV
I have installed a set of ARNOTT GEN III air springs on my 2000 P38 and currently having a custom set of Bilstein shocks made to maximize the extended lengths these bags offer.
The stock Bilstein shocks for the P38 have lengths as follow:
B46-2214 Front: 338mm(13.3”) – 535mm(21”)
B46-2215 Rear: 311mm(12.2”) – 482mm(18.7”)
Looking at using the Bilstein 5150 BF5-A195-H1 360mm(14.2”) – 571mm(22.5”)
This means you have to install a 1” higher bump stop on the front and 2” higher bump stop for the rear to avoid destroying the shock on compression. Using the leverage of the axle geometry gives you 1.5” less articulation on compression in the front and 2.5” less on the rear.
This shock will still not give you maximum extension on the front and if used in the rear will over extend the bag by almost 4”.
So I have called on the Bilstein agent in South Africa who is also one of the best custom system builders for off road racing in SA to make this work for me.
The design so far:
Bilstein 46mm mono tube pressurized gas shock using the bigger new 18mm shaft (awaiting specs and confirmation from Germany) with a shock mounted extended canister. Valve rates are left same as the stock P38 values for now.
Front Collapsed: 338mm(13.3”) same as stock so using the stock length bump stops.
Front Extended: 580mm(23”)
This gives 10” travel, with a bit of safety on the collapsed side it is actually 9” travel which is a little more than Arnott recommend and you can adjust this with spacers at installation.
Rear Collapsed: 311mm(12.2”) same as stock so using the stock length bump stops.
Rear Extended: 526mm(21”)
Due to the rear shock mounted at an angle to the axle travel you get more axle travel than shock travel so this gives almost 12” travel on the axle but with the collapsed safety margin is more like 11” which is a little more than Arnott recommend and you can adjust this with spacers at installation.
A ball park estimate for this once off set is around $1600.
Any comments or suggestions on this welcome please!
CRV