john vanlandingham John Vanlandingham Senior Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
I can think of a few people that would benefitt from pondering the last line there. Good to see you got it working. John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
Nubby Tony Wells Elite Moderator Location: Omaha, NE Join Date: 07/08/2008 Age: Possibly Wise Posts: 191 Rally Car: SP Evo IX #112 |
Something we figured out on Saturday that may save other people some heartache...
The valve stems in the Bilstein-sourced Schraeder valves were loose so they were leaking nitrogen. My guy tightened them up, gassed up the struts and sprayed soapy water on them and let them sit for an hour to make sure they weren't leaking. I just checked them yesterday and no hiss when taking off the valve caps. So maybe don't outright trust those shiny new Schraeder valves are going to hold pressure. |
Nubby Tony Wells Elite Moderator Location: Omaha, NE Join Date: 07/08/2008 Age: Possibly Wise Posts: 191 Rally Car: SP Evo IX #112 |
OK, some video we shot for whatever good driving over speeds bumps is for setting valving. It definitely was useful to tell us we had too little rear rebound but I'm not sure how much you can extrapolate this out to real world. Watching these in HD at 1/4 speed makes me think: too much front compression, too little front rebound and that is how it feels in the car. But just driving it on the street feels good.
Hopefully get the car out on gravel soon, but if you're interested, here ya go: video: https://www.youtube.com/playlist?list=PLKZ4A7eyCoHAO6AIRb-E7INScqM4jvln1 |
john vanlandingham John Vanlandingham Senior Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
That hain't gonna tell you nuthin. Find some gravel and some speed..Hit shit sideways.. What in the end is the valving? And the sprangs? John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
Nubby Tony Wells Elite Moderator Location: Omaha, NE Join Date: 07/08/2008 Age: Possibly Wise Posts: 191 Rally Car: SP Evo IX #112 |
Probably the starting point is corner weights, and this is 1/2 tank of gas, rally-ready minus the meatbags in the racing shells: LF 986 975 RF LR 678 670 RR Cross 1654 49.96% Total 3310 Front springs are 300 lb-in, rears are 250 lb-in with a motion ratio of something like 0.8, e.g. the rear shock moves less than the wheel. Single spring F/R with almost no preload, the car settles to ride height. 200 PSI nitrogen F/R. As far as valving, I will have to get back to you because my machinist/ex-jumpy truck racer fiddled with them and now I don't know what they are. I have the original valving on my work computer which I can post up on Monday which is probably a better baseline. I'm going to take the car out to gravel roads tomorrow, but I don't know if I'll be able to do much testing. We've had a couple of dry days after quite a bit of rain and I don't want to tear up public roads unless my entry fee fixes them. |
Nubby Tony Wells Elite Moderator Location: Omaha, NE Join Date: 07/08/2008 Age: Possibly Wise Posts: 191 Rally Car: SP Evo IX #112 |
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Nubby Tony Wells Elite Moderator Location: Omaha, NE Join Date: 07/08/2008 Age: Possibly Wise Posts: 191 Rally Car: SP Evo IX #112 |
OK, the last of the stuff I can think about anyone might want to know...
Front bump stops are what came with the struts. These are the rear bump stops: http://store.resuspension.com/product.php?productid=18355&cat=334&page=1 Before we had springs we let the car down on the lift with just the dampers bolted up and it would get down to VW-dumpy-boi-approved ride height before the bump stops prevented further bump travel. The front struts are about equally divided between bump and droop travel, so 4" either way. The rear shocks have more bump than droop due to the rear suspension on the Evo binds at full droop, so the pics on the lift of full rear droop is all you can get w/o modifying that ball joint that binds first as I believe JVL has already witnessed. I should mention that nothing the car is doing is bad, it's SO much better than before I'm ecstatic. But since we have the power to change valving, springs and bumps stops, why not try and get these a bit more dialed-in? |
Nubby Tony Wells Elite Moderator Location: Omaha, NE Join Date: 07/08/2008 Age: Possibly Wise Posts: 191 Rally Car: SP Evo IX #112 |
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Ascona73 Bob Legere Junior Moderator Location: Spofford, NH Join Date: 03/07/2007 Age: Possibly Wise Posts: 308 Rally Car: 1971 Opel Ascona |
Quick couple of questions for you. A friend of mine just ordered a set of the 46 mm Bilsteins, I've got them in my hands now. How does the cartridge get disassembled? It's obviously under gas pressure and has oil in it. I need to take them apart to get the pins machined. I find it interesting that recommended gas pressure is not mentioned, nor is oil volume in any of Bilstein's literature. Neither is disassembly for that matter, but obviously it needs to get done to perform the same machine work you had done. I'm going to add the schrader valves up top as well. Thanks for any input you might have. Opel is a 4-letter word... http://www.flickr.com/photos/10498579@N07/sets/ |
Nubby Tony Wells Elite Moderator Location: Omaha, NE Join Date: 07/08/2008 Age: Possibly Wise Posts: 191 Rally Car: SP Evo IX #112 |
When I ordered the struts from Streetwise I asked that they depressurize them as we didn't have the equipment, maybe a roundy-round shop could do that for you or maybe someone knows a trick I don't.
Once the gas pressure is out of them, you press down on the rod guide, it drops down and you have access to a circlip for disassembly. Pop the circlip and the rod guide can come out with along with everything else. When you put them back together gas pressure will push the rod guide up against the circlip to seal up the strut. We're running 200 PSI which is the same as the ASN spec on the rear and that seems about right. Dennis Grant from "Autocross to Win" fame says Bilsteins cavitate at around 80 PSI on a shock dyno, he ran 150 PSI in his AutoX car, so 200 PSI gives us some headroom. For oil volume, either measure what comes out (and post it up) or what we did is use the valving manual which can be found here: http://www.bilsteinus.com/fileadmin/user_upload/user_upload_us/pdfs/motorsport/en/valvingmanual_71to78.pdf You didn't mention travel, but 320 ml is what all 8" 46mm piston Bilsteins use with the exception of that one shock with a bulb end. So we went with 320 ml. As mentioned before, make sure your Schrader valves are holding pressure. We got ours from Bilstein and the valve cores were loose and leaked from the factory. Once they were snugged up, they held pressure fine. |
john vanlandingham John Vanlandingham Senior Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
To add a schrader valve, yes.. But soft jaws and LOW clamp in power chuck and stick them in to the very end of the chrome and you're OK.. What valving didya get? I presume for the Japonaise thing we talked about.. John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
Ascona73 Bob Legere Junior Moderator Location: Spofford, NH Join Date: 03/07/2007 Age: Possibly Wise Posts: 308 Rally Car: 1971 Opel Ascona |
Thank you for the input. We went with 8" travel fronts, and 9" travel rears. Perhaps a call to Bilstein is in order for the recommended pressures and fluid levels. As well as how to depressurize with minimal "oil explosion". Opel is a 4-letter word... http://www.flickr.com/photos/10498579@N07/sets/ |
Ascona73 Bob Legere Junior Moderator Location: Spofford, NH Join Date: 03/07/2007 Age: Possibly Wise Posts: 308 Rally Car: 1971 Opel Ascona |
Yup, same 1991 Sentra. I originally called Bilstein for valving recommendations, told them what my friend was using the car for, corner weights, spring rates we'd be changing to, etc. They ended up recommending the 380/180 up front and 300/120 out back. We're going with 275 front, 225 rear springs with flat-wire helpers. Mostly rough tarmac hillclimbs. Opel is a 4-letter word... http://www.flickr.com/photos/10498579@N07/sets/ |
john vanlandingham John Vanlandingham Senior Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
Weight of car and weight of front? Cause that valving would be nice on a 1230kg 90s Dubya Arsey Car John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
john vanlandingham John Vanlandingham Senior Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
Fer real..Chuck them up and hack the pin off + a little to your anticipated LOA...pilot. Drill thru...It goes Pffffffft..... Experience has shown that anywhere from about 100 to 250 Pea Ess Eye gasdrück und alles ist in ordnung. John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |