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I'm interested in upgrades to the Reatta suspension for improved handling. I feel the handling of my Reatta has lots of room for improvement, and I expect that the potential is there. I don't deny that the factory equipment was not intended to provide sports car handling. <P>I'd like to make the ride somewhat more firm, and significantly reduce body roll in cornering. Maybe there is also some room for improvement in driver feedback.<P>In some of today's premium cars, the suspension engineers design in carefully chosen combinations of bushing compliance and springs and dampers, for an optimum combination of ride and handling. I suspect that this was not a primary design goal in the Reatta suspension design. I suppose at the time, GM wanted maximum reuse of Riviera componentry, and the premium touring coupe/sedan target had not yet solidified at GM. I mention this because I believe in some cases it can be hard to improve upon the factory package, but in the case of the Reatta, I think the potential is there.<P>I'd like to hear any ideas you guys have about upgrades providing the most improvement. I have searched the archives and found some discussions of tire profile, but very little mention of anti-roll bar bushings and strut and spring combinations. Does anyone have any experiences in these areas? <P>A quick first upgrade I've done on other cars is firmer anti-roll bar bushings and end links. Has anyone done this? If so, where can I find the parts?<P>Thanks

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Hi Carl;<P>Just did the endlink grommets and bushing upgrade on my 96 Riviera and 89 Reatta.<P>The Riv had tired rubber bushings and end links and there was a huge improvement. The car corners flatter, less nose dive and less rear lifting on braking. I was amazed. Easy to do on the driveway also!!<P>Did only the front endlinks grommets on the Reatta, and to my amazement the car already had polyurethane grommets that were slightly worn.<P>Does anyone know if this is stock or did a previous owner make the upgrade?<P>End result ... slightly improved handling. For $9.69 well worth it.<P>I ordered mine from Summit Racing Equipment. 1-800-230-3030 part number ENS-9-8105R (R stands for red polyurethane, you can get black also) I believe I ordered the heavy duty polyurethane grommets and tourqued them down as tight as I could to the end of the threads. No increase in harshness or any negative effects all beneficial. I recommend that everyone does this upgrade.<P>The rear sway bar attaches and is anchored in bushings that are the weirdest thing I have seen, Absolutely no idea how to upgrade.<P>Hope this helps, Robert<p>[ 09-07-2001: Message edited by: Robert Fletcher ]

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PS I have 225-60-15 Yokohama AVS dB tires on the stock rims.<P>infomercial follows... really great tires<P> <BR>Quiet ...Comfortable...and Ultra High Performance<P>While this combination of capabilities was once thought to be unattainable, Yokohama?s AVS dB shows that it is possible. The AVS identifies this tire is a member of their Advanced Vehicle System family and the dB is the abbreviation for decibel (the unit of measurement used to quantify sound pressure). Therefore, the AVS dB name is fitting because this is Yokohama?s quietest ultra high performance tire yet.<P>The directional tread design combines several key design elements which enhance the AVS dB?s capabilities. A continuous center block provides uninterrupted rubber-to-road contact while "tusk" shaped grooves minimize noise and maximize water drainage. Additionally, all of the tread block sizes and shapes are designed specifically to help neutralize one another?s noise patterns.<P>Internally, the AVS dB uses a casing design with Active Flex Control (AFC) technology which helps absorb bumps without abandoning the lateral stiffness required for responsive handling and cornering control. Twin steel belts are reinforced by spirally wound nylon strips to provide long term integrity under high speed conditions while reducing weight and providing more uniform ride quality.<P>Yokohama reinvented their All-Season tread compound technology to stretch the AVS dB?s range of operating temperatures in order to allow them to hold the road in summer?s heat while providing light snow traction in winter?s cold.<BR> <BR>You are now returned to your regular browsing, Robert

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There are several front and rear sway bars listed for the Reatta/Riviera. The problem, my parts book does not list the diameter for all the bars. It appears there were only two rear bars, a soft Riviera and the other for all Reattas and FE3 package.<P>I have a '90 and '91 but have never measured the bar diameters. <P>The other option is springs. Since the Riviera has more weight on the rear, it's rear spring should be stiffer.<P>If you had the equipment to make an adaptor, you could move the attachment point and stiffen the existing bars.

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Glad to hear about the Yokohama tires as I plan to install the same ones although in a 215/60-16. I'm not sure if the Riv. has a stiffer rear spring or not, but according to the alignment specs., the ride height is lower than the Reatta and they had an air strut option, which I am installing on my Reatta.

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2seater-<P>If you are interested in improving handling you could put a wider lower profile tire on your 16 inch rims. A 245/50/16 would have a diameter of 25.6457 inches and the stock 215/60/16 tires 26.004 inches.<P>The tire calculator at <A HREF="http://www.miata.net/garage/tirecalc.html" TARGET=_blank>http://www.miata.net/garage/tirecalc.html</A> is a very good tool to compare sizes.<P>Don't know if your rims are wide enough or the wheel wells large enough. It would be great if a shop would let you try them out. Perhaps someone else has tried this size?<P>You will be very happy with the AVS Dbs. <P>Robert

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Thanks for the suggestion. I have run lots of calculations on various tire/rim/profile combinations and to be honest I haven't even purchased the 16" wheels yet. Handling is somewhat important and I can gain some of the tire width help by changing the offset of the wheel. I have considered a 17" wheel also and am looking for a decent balance between a nice big black tire and a little lower profile. I am old school enough to not like the look of the 20"+ wheels with rubber bands stretched over them. Just not my style. When I change my front struts I am going to take some dimensions from the springs and see what might be available is a little shorter but higher rate spring.

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Hi Carl;<P> Those are the ones. They are much harder than rubber and I would be 75% certain that they are urethane.<P>The energy end link grommets come in regular and heavy duty. I used heavy duty. They are slightly larger in diameter. I used the original hardware.<P>Summit offers free shipping but charge a $6 or $7 box fee. If you are going to start driving aggressively this would be a good time to order and install an transmission cooler.<P>Good luck and please keep us posted as to any other suspension upgrades you are contemplating.<P>Robert

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Prothane sway bar bushings (http://www.prothane.com/Main_Menu/main_menu.html) are available at many parts stores - with the links they are $14.99, just the bushings and collars (8 each), $9.99 at the local MM&J. <P>These are dark red. (Have a set of the bushings I have not installed yet. Are marked "urethane".<P>Considering that the Reatta is a front engined (engine in front of axle), FWD vehicle, you can concentrate on the front end and the rear will follow. <P>Rear sway bar is only 5/8" which will not do very much on a 3000 lb+ Reatta (anti-roll effect is a function of the square of the diameter - almost said "torsional resistance" but have been chided for using such strong language) - and decreases with the length of the side arms which are rather long on the Reatta. <P>All of this means that the rear sway bar is more for show than for effect. Some marketroid probably said "we need one". There just is not enough weight back there for a sway bar to do more than just hike one rear leg up in a corner<P>IMNSHO the Reatta is a fine driving car for covering long distances quickly and in comfort and be able to get out of dangerous situations. <P>If you want to go really fast on a road course or in an autocross for the same money it would take to make a Reatta even semi-competitive you can buy a whole Fiero V-6 with 5-speed (true rear-mid-engined car) and make something really quick. Then tow it behind the Reatta.<P>My personal philosophy is to have single purpose vehicles which do that well, not ones that do a number of things poorly. The Reatta is one of these. Have four others (including a V-6 m/t Fiero) for different missions.

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Padgett, I went to the Prothane site and sent them an email re what they had for either Reatta or Allante. They responded today saying, "We do not have in bushings for the Buick Reatta or the Cadillac Allante<BR>There are no plans to develop anything for these two vehicles. Thank you for your inquiry. Fred". How did you manage to get something from them that fits, unless you knew to specs and they were/are unaware that something they sell fits our car?

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Guess it was by not asking 8*). Think what they meant is that they do not make anything *specifically* for the Reatta however much of what is underneath is just "generic GM".<P>In my case I just bought a set of generic front anti roll bar bushings for the link which is just a long bolt with four bushings, four collars, and a sleeve. What varies depending on the application (keep in mind, all of my cars are GM) is the bolt and sleeve length.<P>I strongly suspect that the body mounts, front roll bar mounts (that rear bar is a bit odd but doesn't do much), and A-arm bushings are also "generic GM" though have not looked specifically.<P>Probably their book just does not list low volume elements like the Reatta - may have better luck asking about Riviera. This is where it is handy to have a parts book to see what interchanges.

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Yes, I agree that the links are almost always generic and easily replaceable. I first discovered this when I was a kid rebuilding a 62 Volvo P-1800. Went to the dealer to get links and nearly choked on what he tried to charge me for what looked to this inexperienced eye to be pep boys shock tower bushings. From then on . . . I have purchased urethane sway bar bushings in the past based on the sway bar diameter and made them work. Wasn't sure how quirky the Reatta is. Aside from the links, are you uisng urethane anywhere else on your car? Anyone?

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I am a little confused about all the talk about replacing the end link bushings. <P>On the front of the Reatta, the end link is a special part with a self aligning studs, there is no rubber or any other soft part to deterioate. The only soft parts are the bushings at the attachment points on the engine sub frame.<P>In the rear, the ends of the sway bar are attached directly to the rear strut by a bolt, there are soft bushing on the sides to eliminate metal to metal contact. The rear bar has a bracket with soft bushing on each end of the bracket. This bracket (one one each side of the car) attaches to the sway bar and to the rear sub frame.<P>Where are you putting these polyurethane bushings?

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Barney now I'm confused. The front sway bar link looks conventional. True the bushings appear to be plyurethane from the factory (are yellow). Body bushings do look "different" but do not know if there are any functional differences. Was talking about the "front stabiliser shaft link", what is an "end link " ?

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The parts as replaced on my Reatta, Robert<P>javascript blush.gif" border="0pen_image('/cgi-bin/ncommerce3/ExecMacro/prod_image.d2w/report?prrfnbr=2499')<P>Should open image...

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