Tony Posted September 24, 2008 Report Share Posted September 24, 2008 According to the Mazda workshop manual after the coils are installed the front top wishbone bolts can to be tightened with the wheel off the ground. This is totally wrong because if wheels are off the ground and the entire suspension system is relaxed. Once tightened and lowered to the ground the suspension will compress and rotate the locked bushing about 45 degrees, effectively pre-loading the bushing. The first image is the bushing under load (forgive the quality) to the right of the bright metal you can just see the rubber fingers of the bushing swept at an angle. The method to measure the trim height is mid wheel to mid centre of the wheel arch in the vertical plane Remember the coils had just been fitted by the dealer..... The measurement was 360mm I then released the bushings so they could relax, here is the drop 20mm drop!!...... Considering the lowering coils are designed to give a 30mm drop isn't it odd that the bushing "according to Mazda" should suspend 20mm of it? If you intend Mazda to install the coils please be wise for these reasons... 1: A loaded bushing will act like a flotation device and affect the handling 2: A loaded bushing will wear very quickly 3: No Geometry will be final because of #2 4: The correct trim height should be 340mm + - 5mm front and rear Just to challenge Mazda's method, since the bushings metal inner core is locked and only the rubber is allowed to rotate then shouldn't that rotation start with the bushings relaxed at mid-point? Quote Link to comment Share on other sites More sharing options...
CIH Posted September 24, 2008 Report Share Posted September 24, 2008 You'd think after 20 years of Roadsters Mazda would have it down to a fine art by now... Quote Link to comment Share on other sites More sharing options...
Tony Posted September 24, 2008 Author Report Share Posted September 24, 2008 You'd think after 20 years of Roadsters Mazda would have it down to a fine art by now... They did until regulation got in the way...... And i can tell you this hand on heart the NC has the best chassis i have every seen in 30yrs of calibration....... once all the EU crap has been scraped off. Quote Link to comment Share on other sites More sharing options...
Tony Posted October 1, 2008 Author Report Share Posted October 1, 2008 Another example today.... Bushings pre-loaded 365mm Bushings relaxed 350mm Repair time: 15sec, cost to the customer: £0, performance gains and future maintenance savings £immeasurable. Quote Link to comment Share on other sites More sharing options...
jammy Posted October 1, 2008 Report Share Posted October 1, 2008 Another example today.... Bushings pre-loaded 365mm Bushings relaxed 350mm Repair time: 15sec, cost to the customer: £0, performance gains and future maintenance savings £immeasurable. sounds like a advert for barclay card i know i want a mx-5 at some point though.watchin tony set one at the centre left me in amazment of the prospects off this car soon as i got 1 it would be straight to wim for some serious tweeks to the chassis when fitting the rear beam on my astra.it says to fit beam bolts in and lower car.bounce rear 3 times then jack up and tighten bolts....surely this would have the same effect on the bushes as you found opn these tony? and wondering if i should tighten it up whilst on the ground Quote Link to comment Share on other sites More sharing options...
Tony Posted October 1, 2008 Author Report Share Posted October 1, 2008 In the air i think you mean...... If you did you would have a dragster, scary thing is the bushings would hold some serious preload so the handling is anyone's guess? Quote Link to comment Share on other sites More sharing options...
CIH Posted October 2, 2008 Report Share Posted October 2, 2008 Wouldn't the Mazda techs measure the ride-height post fitting ? Guess not huh ? Quote Link to comment Share on other sites More sharing options...
jammy Posted October 2, 2008 Report Share Posted October 2, 2008 In the air i think you mean...... If you did you would have a dragster, scary thing is the bushings would hold some serious preload so the handling is anyone's guess? looks like i shall be crankin it off and tightening up when on ground then does seem a bit od on the rear now ive had a week to get use to it again lol Quote Link to comment Share on other sites More sharing options...
Tony Posted October 2, 2008 Author Report Share Posted October 2, 2008 Wouldn't the Mazda techs would measure the ride-height post fitting ? Guess not huh ? Apparently not..... maybe it doesn't say so in the manual Quote Link to comment Share on other sites More sharing options...
kgh Posted October 12, 2008 Report Share Posted October 12, 2008 I checked the ride height of my NC 2.0 Sport - Eibach springs fitted by dealer on 3rd August 2007 Front 345mm - Rear 340mm I looked in the front wheel arches and found twisted bushes! I released the bushes and checked the ride height again Front 340mm - Rear 340mm Has the 5mm drop upset the alignment? Quote Link to comment Share on other sites More sharing options...
Tony Posted October 12, 2008 Author Report Share Posted October 12, 2008 I checked the ride height of my NC 2.0 Sport - Eibach springs fitted by dealer on 3rd August 2007Front 345mm - Rear 340mm I looked in the front wheel arches and found twisted bushes! I released the bushes and checked the ride height again Front 340mm - Rear 340mm Has the 5mm drop upset the alignment? A fraction.... Drops that i have imaged where between 15 and 20mm and they needed attention. A tell-tail sign apart from any handling changes is the steering wheel position. Quote Link to comment Share on other sites More sharing options...
kgh Posted October 13, 2008 Report Share Posted October 13, 2008 I checked the ride height of my NC 2.0 Sport - Eibach springs fitted by dealer on 3rd August 2007Front 345mm - Rear 340mm I looked in the front wheel arches and found twisted bushes! I released the bushes and checked the ride height again Front 340mm - Rear 340mm Has the 5mm drop upset the alignment? A fraction.... Drops that i have imaged where between 15 and 20mm and they needed attention. A tell-tail sign apart from any handling changes is the steering wheel position. I looked up the cars last alignment report (7th July 2008) which showed the ride height to be 355mm all round which can't be right When your machine is working again I'll arrange to drop in and let you see it. Quote Link to comment Share on other sites More sharing options...
Tony Posted October 13, 2008 Author Report Share Posted October 13, 2008 I checked the ride height of my NC 2.0 Sport - Eibach springs fitted by dealer on 3rd August 2007Front 345mm - Rear 340mm I looked in the front wheel arches and found twisted bushes! I released the bushes and checked the ride height again Front 340mm - Rear 340mm Has the 5mm drop upset the alignment? A fraction.... Drops that i have imaged where between 15 and 20mm and they needed attention. A tell-tail sign apart from any handling changes is the steering wheel position. I looked up the cars last alignment report (7th July 2008) which showed the ride height to be 355mm all round which can't be right When your machine is working again I'll arrange to drop in and let you see it. Are you on 16" or 17" wheels? Quote Link to comment Share on other sites More sharing options...
kgh Posted October 13, 2008 Report Share Posted October 13, 2008 I checked the ride height of my NC 2.0 Sport - Eibach springs fitted by dealer on 3rd August 2007Front 345mm - Rear 340mm I looked in the front wheel arches and found twisted bushes! I released the bushes and checked the ride height again Front 340mm - Rear 340mm Has the 5mm drop upset the alignment? A fraction.... Drops that i have imaged where between 15 and 20mm and they needed attention. A tell-tail sign apart from any handling changes is the steering wheel position. I looked up the cars last alignment report (7th July 2008) which showed the ride height to be 355mm all round which can't be right When your machine is working again I'll arrange to drop in and let you see it. Are you on 16" or 17" wheels? 17" Quote Link to comment Share on other sites More sharing options...
Tony Posted October 13, 2008 Author Report Share Posted October 13, 2008 I checked the ride height of my NC 2.0 Sport - Eibach springs fitted by dealer on 3rd August 2007Front 345mm - Rear 340mm I looked in the front wheel arches and found twisted bushes! I released the bushes and checked the ride height again Front 340mm - Rear 340mm Has the 5mm drop upset the alignment? A fraction.... Drops that i have imaged where between 15 and 20mm and they needed attention. A tell-tail sign apart from any handling changes is the steering wheel position. I looked up the cars last alignment report (7th July 2008) which showed the ride height to be 355mm all round which can't be right When your machine is working again I'll arrange to drop in and let you see it. Are you on 16" or 17" wheels? 17" Then assuming the height is still the same then it's needs checking again. Quote Link to comment Share on other sites More sharing options...
kgh Posted October 14, 2008 Report Share Posted October 14, 2008 I checked the ride height of my NC 2.0 Sport - Eibach springs fitted by dealer on 3rd August 2007Front 345mm - Rear 340mm I looked in the front wheel arches and found twisted bushes! I released the bushes and checked the ride height again Front 340mm - Rear 340mm Has the 5mm drop upset the alignment? A fraction.... Drops that i have imaged where between 15 and 20mm and they needed attention. A tell-tail sign apart from any handling changes is the steering wheel position. I looked up the cars last alignment report (7th July 2008) which showed the ride height to be 355mm all round which can't be right When your machine is working again I'll arrange to drop in and let you see it. Are you on 16" or 17" wheels? 17" Then assuming the height is still the same then it's needs checking again. I measured the heights again this morning and the height is 340mm all round. Interestingly since the last alignment I have acquired a second set of wheels and have changed sets 3 or 4 times. I change the wheels one side at a time using two jacks. This would shift a lot of weight to the other side (even more than the body roll when cornering ). Could this have an effect? Quote Link to comment Share on other sites More sharing options...
Tony Posted October 14, 2008 Author Report Share Posted October 14, 2008 The body roll would be high momentarily while the suspension settles but after that it should be the same. Quote Link to comment Share on other sites More sharing options...
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