82transam

iTrader: (18)

Robert - How many miles do you have on your setup? I'm wondering how the control arm bushings have held up, as well as the delrin lower steering shaft bushing. After only 5000 that lower shaft bushing had worn considerably on mine.

Like the others on here, the vibration came and went with different speeds, but slightly off center turns, like changing lanes usually shook like crazy...

85turbo12a

and your spare change is well noted and appreciated, i spoke to you about the conversion at DGRR2011 before i bought it as well, also i suspect my ackermman is incorrect as well, i think i need to put the stock steering arms back on it instead of the billet pieces that came with it, the steering shaft is an area of interest for sure, im not crazy about that bushing either, but due to the workload of this engine/suspension/nightmare conversion decided to run with it, i might change it to a ball bearing later on, as for the collapsable shaft, im not sure what to do there, maybe i can melt some urethane into it to fix it like factory i dunno, i have not had the chance to pull the front apart again to see why my struts have side wiggle in them...that has me puzzled for now, all that is very low miles...

here is a run down of my steering details easily viewed in the pics here https://www.rx7club.com/v-8-powered-...build-1009701/ its just FYI and for comparison reasons as we all try to figure out wtf is causing this.

i have a manual 15:1 rack
solid alum offset rack bushings
ALL energy suspension bushings/tie rod boots
new ball joints, wheel bearings have 6500miles and are adjusted proper
KYB strut inserts, 6500miles
RE-speed Xmember/steering arms
new tie rod ends
tie rod adapters are maximized on the threads, meaning i have little adjustment for toe needs so maximum amount of thread is engaged
.750 thick roll center blocks under the strut
i have 280# springs
adjustable camber plates
custom spring tops riding on torington bearings
15x7 +35 wheel
205/50/15 tire nitto neo-gen

i never took the strut insert apart for the current mods, i just added the adjustable camber plates, and the .750 roll center blocks, that i am going to remove and try without. i never had this vibe before, and at first i was blaming the new tires, but i dont think they are the cause.

oddly the car is super reactive, the slightest input will result in direction change, but when the wheel is vibrating at its worst the car tracks straight and true....

im thinking an all new properly adjustable LCA is in order, not just for suspect vibe, but because i dont like the kit's design, i think its weak.

something like this, or maybe a full billet alum part...just to be obnoxious

82transam

iTrader: (18)

^I was going to ask what was different about your car, that answers my question lol. I've been looing at that lexus V8 for my ae86, how do you like it?

Not to derail the thread too much - The LCA you posted above looks MUCH better than what the kit comes with. I'd be interested to see what you come up with A ball bearing of some kind to support the lower half of the steering column would be a good change too since it's what many cars use from the factory in the first place - at least all the ones I've worked on...

rwatson5651

iTrader: (5)

The factory steering arms will only make your ackerman issue worse. They are designed to add ackerman by shifting the attachment points to the inside. This only works on a rear steer setup. On the front steer setup you are now running you will need to shift the attachment points to the outside. If you could swap sides with the original steering arms they would fix the ackerman but they would interfere with the brake rotor. If you have the resources you could have a set made to offset the attachment points to the outside as far as possible without hitting the rotors and this would help.

I considered doing this, but my car coners soooooo well that I was concerned that fixing the ackerman issue might help my parking lot performance but hurt my cornering performance at the limit of adhesion. After studying and learning as much as I could I think it corners better without the ackerman. the ackerman would add several degrees of steering input for the inside tire, while under extreme corneing has very little weight and because of the diminished weight cannot tolerate as much of a slip angle, in other words it would break loose much easier, so I made a decision to leave it as it is.

rwatson5651

iTrader: (5)

I estimate about 20 to 25 thousand, I havent noticed signs of wear, but since this may be an issue I will check them closely soon when I take the front end apart to install my KC raceware hubs, larger rotors and FD calipers. I examined the delrin bushing when I fixed my steering shaft and it shows no signs of wear at all.

rwatson5651

iTrader: (5)

I really urge you to check it as your symptoms sounds exactly like what mine was doing and since the fix the vibration issue has completly dissappeared for thefirst time.

85turbo12a

im not sure if i will get to it in time for DGRR, but if i get it apart again i will probably just fill the joint in the shaft with 2part epoxy just to eliminate any movement

if it keeps it up ill say hell with the collapsing joint and weld it

all i know is the vibe is annoying and it starts right at interstate speed making the DGRR trip a promising source of annoyance due to the 13 or so odd hour ride to get there....it wont effect me in the mountains since the speeds are so much lower.

85turbo12a

ok todays investigation was centered on the struts and that side/side play found when grabbing the top of the tire and shaking the car sideways, i found it in the strut insert and strut tube itself, i wrapped some alum sheet stock around the insert and put them back in and tightened up the nut real hard and most of the play is gone, but what is left is in the insert itself....

also...my KYB inserts have like no gas loading to them....i cant remember if they ever did to be honest, its been so long since i bought them, but they do not extend on their own, but they do provide resistance both directions, so input on that would be nice, i will probably order a set of tokico blues for it anyway, since that is what i originally wanted but could not afford at the time, these only have 7k miles on them roughly, and are about....4yrs old.

everything else is tight as hell, there is no slop in bearings, tie rods, ball joints, not even the way bar....the slightest minute input of the steering wheel results in direct and strong movement of the hubs, and vice versa, so there is zero backlash in the rack and shaft/ujoints, the RLCA is what it is....its tight and shows no sign of destroying the bushing, though i still dont like the design IMO.

I still want to get the steering column back out at some point and investigate that collapsible joint, but that is the last resort really...i know i can not feel anything at all in the area of foreign movement in any part of the front end, except that strut play....

and.....the vibe remains....

rwatson5651

iTrader: (5)

I just put my car up on the stands so I could check my bushings and they are still good. Don't seem to have any excess play at all.

82transam

iTrader: (18)

Weird! Maybe I damaged mine while installing them or something. I'd ask the guys I sold my kits to how they are holding up but honestly I can't even remember who I sold them both to lol.

Wish I could help you guys get your kits sorted out, I took the easy way out and gave up... Good luck!

rwatson5651

iTrader: (5)

After I found the free play in the steering shaft I have have been happy as a lark, vibration free, yoo hoo!!!!

What I'm doing now is upgrading my brakes.

Twilightoptics

iTrader: (1)

Stock steering does the same thing. When there is slop in the steering gear/rack the wheels have the ability to move back and forth even though you're keeping the steering wheel straight. A slight corner/off center exhibits it and the speed grows the vibration. I've had 3 different boxes in my car with 298,000miles. It does exactly as this complaint is described. Worse with previous boxes that had more play than my current one.

I am not convinced of a problem with the RE setup and still have it on my list to purchase. Just my $.02

85turbo12a

im not trying to start an argument, its just VERY cooincidental that we all have the same symptoms at the same speeds with different wheel/tire, engine/suspension set ups, only the common denominator being the rack set-up, and in my case, i was vibration free to near abouts 150mph until i installed the rack set up and a new set of tires, and im pretty sure at this point its not the tires. its odd...its not like its a deal breaker, its a nice set up, though IMO could use a few improvements to the "kit", we just need to root out the culprit and spread the word to the others with the issue.

I have NOT taken my steering column back out at this time to investigate any play in the shaft, that im 100% sure its tight. there is ZERO backlash in my steering, and ZERO slop in any part of the front end with the exception of the strut inserts themselves, and im not sure what i have is out of the norm, its only very very slight at this point.

HRnico

iTrader: (7)

"Very slight" but annoying as hell. In mine, I had to drive (hammer) the the new lower steering shaft intothe Mazda upper section. I shimmed the u-joints on the D shaft and tightened the rack and it helped the vib, but its still there. My 86 se has the same vib and its all stock with 150K on it.

Whisper

Good to see this discussion is still going, and good to see I'm not the only one having these symptoms. I don't have any good news, but do have another question.

I've been busy/lazy, but I finally got around to swapping the rear brakes for the old ones that I had before vibration happened. No change, still shakes. One new thing I noticed when swapping rear brakes, is that I have a bit of what seems to be bearing play in the rear? I can grab rear wheels on their sides or top/bottom and rock them back and forth a bit, they make a slight clunk. I'll try to take a video to better demonstrate. I've no idea if this is normal or if I need to replace rear bearings. If this is not normal, I wonder if this play can cause vibration at the rear wheels/axle, which is then transferred to the rest of the car. I can definitely feel the vibration in the shifter and the seat sometimes. Maybe first I'll slap a camera on the car to see what the rear wheels are doing at high speeds.

People bringing up the rack conversion as a cause of vibration is also an interesting direction to explore, but I've no idea how and what to look for. My steering wheel does have a bunch of play now, but I think this play is the result of vibration loosening things up, and not the other way around. Of course the steering shaft could be the issue. A pain in the butt to get out, but I guess worth a shot. The derlin bushing is all loose too, I'll see if I can order a new one.

rotornoob

iTrader: (2)

As far as your rear wheels moving like that I would change the bearings. The vibration can be caused by bad bearings. Also double check the u-joint in the drive shaft to make sure that's not where the vibrations come from. If that has been covered I apologise but I didn't read the whole thread just the last post

Whisper

Last I checked the driveshaft, the u-joints were in good shape and it was allegedly pre-balanced when I bought it, so I'm hoping it's not the culprit. If nothing else, I can always get it re-balanced.

Anyway, here's the rear bearing play that I'm observing. It's on both sides, with right side being more prominent. It's hard to hear the clicking/clunking, but you can kind of see the wheels have some give.

Whisper

So I re-did the steering column, to remove any slop, which tightened the steering, but as expected did nothing to eliminate the vibration, if anything it made it more noticeable, since the steering no longer has any free play and picks up even the tiniest bits of vibration.

Oh well, onto rear bearings, I guess.

Nicholas P.

iTrader: (1)

Is it mainly at 40-43mph?

Whisper

No, it's mainly at 55 and up. That's not to say the vibration isn't there at lower speeds, but it's probably not rapid and violent enough to notice.

gonzoguy

I didn't read all the posts but I did your first and glanced through others, have you checked the idler arm? My bushings are bad and from a standstill I will here a loud pop when I turn the wheel like you described.

Whisper

I don't have an idler arm, it's a steering rack.

gonzoguy

Gotcha

Whisper

Ok, so I tried something different. Went to a local AWD dyno shop, and had the car rolling at 60 mph, first with all four wheels spinning, and then just the rear.

The tires/hubs/rotors spun pretty true and smooth. As far as components go, couldn't find anything up front, but the rear end had vibration. Sway bar was shaking a bit, the axle/diff housing was shaking a bit, and the rear shocks were shaking a bit, more so on the right side.

So, besides possibly rebalancing the driveshaft, the recommendation was to swap in a different rear end completely and see what happens. Hopefully I can find one somewhere, 'cause damn. I guess there's nothing else left to do here.

MazdaMike02

iTrader: (4)

Vibrations at those speeds that go away at higher speeds are typically caused by wheels/tires. I would spin up all 4 tires on a balancer to see if theres any runout in the tires, rims and check for shifted belts. You may also want to Roadforce balance, its night and day difference from a regular balancer but costs more.

You can also try balancing the driveshaft yourself with gear clamps.

Oh and as for the rear wheel bearings they are roller bearings (cylindrical shaped rollers, no taper) some in/out movement is normal. I cant watch the video right now..