bjhines Posted November 3, 2006 Share Posted November 3, 2006 To start off... I have no idea if I will live to regret doing this... I am using the finest aerospace bearings I can buy... I expect a failure if more than 7000 pounds of pressure is applied to the TC rod axially through the bearing... The design I am using has a backup washer built in so that failure would not cause a toal collapse of the suspension... but it would probably put me off course... ========================================================== I am trying to solve several problems at once... 1. excess movement of the stock rubber bushings causes unpredictable shifts in handling on a race track... 2. harder bushings and/or overtightening the end nuts will cause the TC rod to flex, fatigue, and eventually fail... 3. most TC rod redesigns place the spherical bearing pivot forward and outward from the stock position, as well as shortening the overall TC rod length... ======================================================== I am totally stealing this whole idea from picures I have seen of Ron Carters BRE 240Z replica... I have managed to contact Mr. Carter via email and I can assume he isn't dead yet due to his redesigned TC pivots... Ron credits Design Products http://www.designproductsracing.com/...aspx?tabid=514 for comming up with this nifty design... They have some really sophisticated thinkers over there... we need to find a way to get them some more exposure... ======================================================== I decided not to bother those busy folks a DP for advice... I put my nose to the grindstone(google) and came up with some pretty good parts to start with... http://www.stockcarproducts.com/susp3.htm I purchased the MBA-12 assemblies... Here are some photos of the parts I have for this project... 3/4" mono ball in a housing that measures 1 3/4" diameter.. It has a nice pair of reducer-spacers to accomodate a 1/2" diameter shaft... Here is an overview picture with the urethane bushings and spacer at the bottom... The spacers put together with the monoball measure 2 1/2" end to end... the urethane bushings stack up to ~ 2 3/8" under compression(these are worn bushings)... in any case... The modification with these parts on the stock TC rods in the stock pivot points would add around 1/16" length to the TC rod... slightly increasing caster angle... which is good.... but not much of a change... Here are some pics of the spacers... I will have to trim them slightly to ensure sufficient free movement of the TC rod when the suspension is at full droop or full compression... The bearing arrangement gives me 11 degrees(*) of deflection... giving me 22 degrees of movement... this should be plenty with a lowered and shortened race suspension... but just to be sure I will have the spacers machined slightly to increase the range of motion to ~15*... giving me enough travel to use them at stock ride height with full droop... {{stock suspension full droop needs ~13* downward deflection at the TC rod pivot}}... The rear spacer will also have to be cut shorter to allow me to increase caster angle with washers in front of the assembly(lengthen the TC rod)... and still be able to screw the nut on the end... The housings can be trimmed to leave only the center section that holds the spherical bearing... the housing will be welded intot he TC bucket so that the centerline of the bearing is inline with the plane of the TC bucket... this will preserve the full length of the TC rod and keeps the lateral/twisting loads on the TC bucket to a minimum... The pivot points can also be raised slightly(~3/4") when they are welded into the TC buckets... This picture shows the housing sitting on top of the stock support washer... ... Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 3, 2006 Share Posted November 3, 2006 With that setup as you've shown it I don't see how you could adjust the TC rod very far. The shims on either side of the bearing are too long I think. I would get some thinner ones so that you can adjust the caster, or maybe cut down the long one on the front and both on the back so that you can stack some washers to on one end or the other to adjust the caster. Quote Link to comment Share on other sites More sharing options...
bjhines Posted November 3, 2006 Author Share Posted November 3, 2006 I mentioned I would be cutting the rear side shims/spacers.. the front side will stay the same (I need to space off the front more, not cut it down shorter)... the set up already adds caster with no washers... with the one stock washer in front(as it sits in the top picture) it adds about 3/16 length to the TC rod.. but barely leaves enough room for the NUT on the end... cutting the rear side spacer will get me as much length as I want... up to 3/4" increase... And the front side needs to have the wide end as a safety backup in case the bearing pops... Quote Link to comment Share on other sites More sharing options...
LLave Posted November 4, 2006 Share Posted November 4, 2006 I guess it would be best to put some sort of turn buckle in the center or fab an adjustable link to get maximum adjustability out of them. Is it necessary or beneficial to have much length adjustability in the TC rod? Or just mod them to add articulation and minimize stiction? Quote Link to comment Share on other sites More sharing options...
Mikelly Posted November 4, 2006 Share Posted November 4, 2006 Although I agree that this would be better than "most" of the other adjustable TC Rods out there (Mine included), I have to comment that those I sold were at minimum the same length as a stocker. Our goal (when ZF Racing was in business) was to deliver a bolt-on solution for guys looking for a little more adjustment than came from the factory, which was none... That said, BJ I'll be interested in seeing how this works out for you. I may well copy this on my own track car... Mike Quote Link to comment Share on other sites More sharing options...
Mikelly Posted November 4, 2006 Share Posted November 4, 2006 I guess it would be best to put some sort of turn buckle in the center or fab an adjustable link to get maximum adjustability out of them. Is it necessary or beneficial to have much length adjustability in the TC rod? Or just mod them to add articulation and minimize stiction? We wanted ours to be adjustable in length to allow for Caster adjustment. Mike Quote Link to comment Share on other sites More sharing options...
bjhines Posted November 6, 2006 Author Share Posted November 6, 2006 I am having these parts machined to allow 3/4" to 1" added length on the stock TC rods... and adding an additional 4 degrees of deflection... I have a date with the machine shop on tuesday... I'll post some more pics soon... Quote Link to comment Share on other sites More sharing options...
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