Tim,
Considering that even the big guys have little data on the differences on
suspension set ups I think you are asking a lot. The rear set up I have
has been "developed"by Aussie MGB racing fanantics. These types of people
cut, weld, instal, try and try again. They know it's either better, good,
lousy by belting it up and down the road and taking to auto-cross to test
reliability - all by the seat of their pants. Basic engineering tends to
suggest that a vertical shock tube will be more efficient than an angled
one -albeit kneed. We are only concerned with vertical movement on a rear
axle and the geometry is not like the front so I suppose only the value of
the shock resistance is a concern. But as I ma not a suspension wallah I
would like to hear other views - especialliy from experts !!
At 09:42 AM 6/7/00 -0700, Tim Economu wrote:
>Peter:
>Thanks for the response. I appreciate you not wanting to inject a commercial
>into the list but I think these ideas are worth of being shared. I hope you
>don't mind.
>
>My worry is that the tube shocks may actually do more harm than good. The
>suspension was specifically designed with the geometry that it has. And it
>was designed with the attributes of the lever type shock absorbing system.
>To do changes to this designed-in geometry with no engineering principles
>because you have heard that it might increase the performance of your car
>(or because it might improve the ride slightly) seems just risky to me.
>Especially since the suspension is actually a part of the "safety equipment"
>of the car. What if the poorly engineered shock mount breaks when you are
>maneuvering out of the way of that big SUV? Who is responsible for that
>design?
>
>Now if someone has actually engineered a new tube shock system, and
>published the test data, so that the data can be confirmed, that is
>different. But I would look for not only slalom track data, but also for
>ride quality information. Like if the ride is stiffer, by how much? The test
>equipment would probably need to be an accelerometer for this test. A lower
>cost way to test would be to drive a marked-off section of bumpy road at a
>fixed speed limit and see how much coffee was spilled out of a cup sitting
>on the passenger floor.
>
>Any way I am not really planning on doing a comparison test between the two
>shock types, because I am actually happy with the way by MG handles now. But
>when I turn attention to the suspension, and ask the question, "shall I
>rebuild by lever shocks?" or, "should I do the shock conversion", I would
>like to have the most educated answer. Is there a well designed AND
>documented conversion on the market?
>
>Thanks for the offer. Maybe someone else on the list wants to do the
>conversion and publish real performance data???
>
>Heck, come to think of it I am not so sure about the V8 upgrade <smile>.
>Maybe I can get a free sample to test?
>
>Tim Economu
>'69 MGBGT with a little ole 1.8 liter four and lever shocks
>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>----- Original Message -----
>From: "Peter C." <nosimport@mailbag.com>
>To: "Tim Economu" <economu@whidbey.com>
>Sent: Wednesday, June 07, 2000 7:05 AM
>Subject: Re: Tube shock conversion data
>
>Tim,
>I am the owner of World Wide Auto Parts in Madison WI. (We are the premier
>rebuilder of lever shocks in the US.) I am on the lists, and have been
>watching your posts. Below is a comparison from the Triumph list done by
>Keith Ehrlich last year. It is somewhat subjective, as he points out, but
>has some insights. I, of course, believe that a properly made lever shock
>is better than the tube conversions... but I'm biased. I think people fail
>to remember that the Brits had knowledge of the existence of tube shocks
>and that the technology wasn't new, yet still they chose to use the levers.
>It is then often argued that it is because they were less expensive. I
>agree, but only when considered as a package with the whole suspension
>which would have had to be re-engineered to accommodate the tube shocks
>_properly_. Tube shocks, compared to lever shocks, are cheaper to
>manufacture. How bad would the press have received a car that came from the
>factory with the mods now employed to fit tube shocks? I hold that the
>suspensions, as they are designed, are meant to have lever shocks. If tubes
>were desired by the engineers (and accountants), then other components
>would have been redesigned.
>Anyway, that's my .02. I am not sending this to the list as I try to
>maintain a non-commercial presence. I am an MG enthusiast as well. If you
>would like to try a comparative test on an MGB having a non-IRS, I will
>donate a set of shocks, valved to your specs.
>Below are the copied letters. Be warned, Keith is more loquacious than I !
><g>
>Thanks for listening.
>Peter C. (800) 362-1025
>----
>
>>>>>>>>>>>>>>>>>>>>>>>>>
>Keith's test report deleted for lack of brevity...
>If you would like to receive a copy just email me and I will forward to you:
>economu@whidbey.com
>
>
>
>Keith Ehrlich
>74 TR6
>
>World Wide Auto Parts
>2517 Seiferth Rd., Madison, WI 53716
>(800) 362-1025 Fax (608) 223-9403
>
>http://www.mailbag.com/users/nosimport
>
>>>>>>>>>>>>>>>>>>>>>>>>>>
>
>
>
Regards
Barrie Robinson
barrier@bconnex.net
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