Datsun Roadster Forum-311s.org

I have an interesting situation. I sold a set of bilstein shocks to a board member and heard back from him that the shocks had lost some of their charge over the years. Bilstein will rebuild them for $65 each, but I did discover that Bilstein offers a lifetime warranty to the original purchaser with receipt. I just happened to have the receipt from 1981 and got an RGA from their warranty deprtment.

I sent them out last Friday and got a call from a customer service rep Tuesday (now that's service!!) saying they were not rebuildable, but they would replace them under warranty. I told the the rep that they had been out of production for many years and wondered how that was possible. She said that their chief tech guy had gone to the drawings and located a replacement part. Well, I received them yesterday and here's what I have:

Fronts: Volvo P1800 (1959-73), part B46-0283
Rears: Corvette (1953-62), part B46-0493

BTW, fronts are the same for both cars, rears are different only in that the corvette unit has the "eyelet" at one end required to attach the shock to the roadster frame crossmember.

Is it possible there really is a readily available, performance replacement shock other than the usual KYB's?

I have a call in with their tech person, Lou Laurenzana. What questions should I ask?

The only one i would ask ARE YOU SURE.

Mitch
Ohio

Hopefully these will work as be kinda nice to have them available from bilstein, how do they compare to something like the kybs?

though with the shock prices I'm wondering if it is for one shock or two each.

FoxyRoadster wrote:Hopefully these will work as be kinda nice to have them available from bilstein, how do they compare to something like the kybs?

though with the shock prices I'm wondering if it is for one shock or two each.

There is no comparison to the KYBs. The Bilsteins are massive. I'm talking HUGE, bigger in diameter than Konis by far. I know a car with a new set of Bilsteins in it, but no engine and the front springs barely touch. You could jump on the front of the car and it just starts to compress.

I think the P1800 shocks need to be cut down, the above mentioned car has a set. I these can be found in Australia ready to go. Perhaps I'm wrong and its only the rears that need to be cut down, but if the Corvette ones fit, that makes life easier. They will still be $100+ per corner, about the same price as Konis. Are they better than Konis? I don't know, but I'd be willing to find out.

Will

Will, I will call the Bilstein tech person again on Monday to get more info. I ran the Bilsteins for several years myself, and indeed the ride was stiff, but not in a bad, rattle your teeth kind of way.

I see the complete set for $330 with free ship on eshocks.com. They also carry the correct Konis for the roadster for $104 each, which seems like an excellent price these days.

With respect to the Bilsteins, this of course assumes thery're a correct fit and properly valved, etc for the roadster. The Volvo and Corvette are at least similar in size and weight and from the same era, so that is encouraging. I did note that the rears will mount upside down as compared to the originals, although I understand that not to be a problem. It will be interesting to find out more...

Mike

The Koni's may be listed but they are not available unless some stash has been found somewhere. I searched extensively. This summer I tried every combo in Koni's online catalog to find something that I thought would work without success, even considering adding adaptors etc. The rear KYBs are also no longer availble from KYB, and if it weren't for the venders (Dean in this case) having them I would be still stuck w/ the GR2s which did not work well with my new composit leaf springs (too soft).

There are many Roadster people out there who know a whole lot more about shocks and valving etc than I do, so I would encourage anyone with knowledge to help Mike with the specific technical questions to ask. I have heard the Bilstein shocks were nice, but what is nice to one car/person/set up is not necessarily what the next person wants. If we were able to confirm that these newer replacements were valved and pressured the same as the old bilstein shocks for the Roadster, at least we would have a starting place. It would be great if we had more options, though I am quite happy with the KYB gas-adjusts on my particular car.

FWIW:
It doesn't look like these are currently available from Dann, but the info may be worth noting, and as my past experience has always been: he's very phone and email friendly for more info.

http://www.datsunroadster.biz/PIC_PAGES ... DN56-3.htm" onclick="window.open(this.href);return false;

SLOroadster wrote:

FoxyRoadster wrote:Hopefully these will work as be kinda nice to have them available from bilstein, how do they compare to something like the kybs?

though with the shock prices I'm wondering if it is for one shock or two each.

There is no comparison to the KYBs. The Bilsteins are massive. I'm talking HUGE, bigger in diameter than Konis by far. I know a car with a new set of Bilsteins in it, but no engine and the front springs barely touch. You could jump on the front of the car and it just starts to compress.

I think the P1800 shocks need to be cut down, the above mentioned car has a set. I these can be found in Australia ready to go. Perhaps I'm wrong and its only the rears that need to be cut down, but if the Corvette ones fit, that makes life easier. They will still be $100+ per corner, about the same price as Konis. Are they better than Konis? I don't know, but I'd be willing to find out.

Will

I wish they had a set of rebuildable ones that could be adjusted during the rebuild like their offroad shocks that would be compatible with the roadster.

So here's the followup after I spent some time on the phone with Lou's assistant at Bilstein. Clarence graciously went to the hard copy archives and pulled the drawings for the original roadster part numbers.

It turns out that the current part number for the fronts, B46-0283, references the same shock as the old 601283 part number I have on my original invoice from 1981. They are identical in every respect.

The old 604461 part number for the rears is no longer in production. The drawings show the original application was for the 66-71 Opel Record, a German small sedan. So here is the technical information for the rear replacement I was sent compared to the original:

Original – 604461, Replacement – B46-0493

body length= 303.0 mm, 304.5 mm
fully compressed length= 297.0 mm, 299.0 mm
fully extended length= 473.0 mm, 474.0 mm

rebound= 253.0, 264.5
compression= 67.0, 70.0
(newtons/force@.52 meters/second)

So the fronts are identical to the old roadster application and the rears are dimensionally almost identical, with just a little more rebound/compression. It is worth noting that even the original fronts are a close fit in the roadster shock tower - they are slightly longer and larger in diameter than the OE shocks; the other difference worth noting is that the replacement rears need to be mounted upside down because the eyelet attachment point is on the body side.

Sorry for the long post, but let me point out that neither one of these shocks was developed specifically for the roadster. Clarence said the same was true of the early z-cars as well and a lot of cars from the era and I suspect it is still somewhat true even today. I asked Dean about the bilsteins once and he said something to the effect that they were a terrible shock for the roadster. Has anyone ever looked at the cross reference for the KYB GR-2’s and the better gas versions the vendors sell? The KYB fronts cross-reference to a large number of full size Chrysler products from the era, including the New Yorker, Plymouth Fury, etc. The KYB rears cross-reference to the same era Edsel, Ford and Lincoln-Mercury full sized cars like the Galaxie, Country Squire, etc. It seems to me that the Bilstein Corvette and Volvo cross-reference are closer to the roadster, so go figure....

I personally have the Konis on my car, because I prefer them, but it’s good to know there are still other choices out there.

mikeb wrote:Has anyone ever looked at the cross reference for the KYB GR-2’s and the better gas versions the vendors sell? The KYB fronts cross-reference to a large number of full size Chrysler products from the era, including the New Yorker, Plymouth Fury, etc. The KYB rears cross-reference to the same era Edsel, Ford and Lincoln-Mercury full sized cars like the Galaxie, Country Squire, etc.

I've looked at just about every cross reference using the KYB charts available online, looking at what kind of mount it had, length compressed and expanded, and thinking some about the weight of the car vs the Roadster etc. Other than when the numbers matched up (i.e. lists the shock as fitting xyz cars, one of which was the Roadster) I didn't find any other shock that had the right (or close) combo of parameters/mounts regardless of the car. The rears, though listed, were NLA from KYB in the Gas-adjust line, all still available in the GR-2. Couldn't find any new Koni's in any of their line that would work. It would be interesting to hear if and how well the Bilstein's work, though as I said I am finally happy with the Gas-adjusts on my particular car. As indicated, it does not sound as though the various manufacturers spent a lot of time adjusting the shocks to the weight of the Roadster in particular, and it does seem to me that there is a lot of weight difference between a Chrysler Cordoba and a Roadster.

Greg,

The fronts referenced are the same shock that Bilstein spec'd and sold for the roadster back in the day, they are identical in every respect. With respect to the rears, I showed the comparative specs to Frank Honsowetz and he said they should be absolutely fine. His opinion is that the most critical dimension is the fully compressed and extended length. Spring characteristics will affect ride and handling far more than shock valving, which is somewhat a matter of personal preference. So bottom line they should work just as well as the originals ever did.

I only mention Frank because I know him (I bought my roadster from him back in 1980) and and I don't want to pass off his knowledge as mine - he is a very knowledgable car guy, and I'm frankly just a rank amatuer . He personally raced a roadster and other Nissan cars for many years and was also the general manager of Nissan Motorsports and currently manages Ed Pink Racing.

Mike

Mike, that is awesome! Sounds like there are alternatives by Bilstein still available then (I don't think I researched them as a option anywhere near how hard I searched Koni and KYB). Not sure why the extended and compressed length is THE critical spec, as I'm sure the springs never allow the shock to get anywhere near either end, but I too am an amatuer when it comes to dialing in a suspension! For my car, the GR-2 valving did not control the rear springs well vs the Gas-adjusts, and I had already switched to the Gas-adjusts in the front years ago over the GR-2s on comp springs because the nose tended to bounce up and down a lot. If at some point I get uphappy with or want to try something different from the Gas-adjusts I will certainly consider the Bilsteins! Would be nice to drive a car with them on. Thanks for your work.

If the WIKI is correct and the KYB part # is KG5447, there are 14 on Ebay right now.
I have no affiliation with the seller, just did a search. Same # listed on Summit, Jegs and Amazon.
http://motors.shop.ebay.com/__?_from=R4 ... nkw=KG5447

If this # is incorrect, then let me know and I'll edit it to a "never mind" and we can advise Steve to update the WIKI

Gregs672000 wrote:Mike, that is awesome! Sounds like there are alternatives by Bilstein still available then (I don't think I researched them as a option anywhere near how hard I searched Koni and KYB). Not sure why the extended and compressed length is THE critical spec, as I'm sure the springs never allow the shock to get anywhere near either end, but I too am an amatuer when it comes to dialing in a suspension! For my car, the GR-2 valving did not control the rear springs well vs the Gas-adjusts, and I had already switched to the Gas-adjusts in the front years ago over the GR-2s on comp springs because the nose tended to bounce up and down a lot. If at some point I get uphappy with or want to try something different from the Gas-adjusts I will certainly consider the Bilsteins! Would be nice to drive a car with them on. Thanks for your work.

The fronts will hit the shock towers if you have a lowered car (In the front.) My source who modifies them has told me this, and I'm going to take his word for it. He knows his stuff. If the Volvo ones clear on a lowered car, awesome, thats great news, but I don't think they will. All I can say is to pull the springs out and move the suspension though its travel to make sure nothing hits before you go drive it.

Will

Will is correct in that the bilsteins fronts are a larger shock. I can only compare them to the konis I currently have installed on the car, but the diameter of the bilstein body is approx 50mm vs 43mm for the konis and length is .5" - .75" greater per my tape measure approximation. I can say from personal experience that I never had any interference problems when I used them. I ran them for about 10,000 miles or so, with motorsports comp springs and cut down bump stops, and drove the car pretty hard. I never raced it, however, so I can't speak to how it would work under racing conditions.

Mike