Confused about combing parts for best bump steer with a lowered miata
#21
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I understand how ackermann works, I was just trying to say the perceived benefits work on the same principle as ackermann. Toe out in a corner to help the car turn in.
#25
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I will say with the knuckles off it’s pretty hard to come up with 7.1mm higher for the NB looks more like 3mm but it also looks like the way the upper and lower ball joint holes are possibly machined differently I might need more sophisticated measuring tools to determine relative to the actual centers of the ball ends.
Don’t have it together to measure yet but NB subframe with NA knuckles and LE tie rod ends goes from 1.25” total toe in at full rebound to 0.75” total toe out at full bump!! Measured with FM hub stands. Kind of shocked me how much it was.
Don’t have it together to measure yet but NB subframe with NA knuckles and LE tie rod ends goes from 1.25” total toe in at full rebound to 0.75” total toe out at full bump!! Measured with FM hub stands. Kind of shocked me how much it was.
#27
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I measure a huge difference in bump steer with all NB parts.
With all NB Subframe NB knuckles, and LE tie rod ends I only get about 1/16” tow out from ride height to full bump. And 7/8” of total tow in at full shock extension. Meaning very little bump steer from around nominal ride height to full bump for lowered suspension setup and what little bump steer there is is in the right direction for stability.
I suspect NB with standard tie rod ends might tow in a bit at full bump and running the le tie rod ends is a little better for the suspension kinematics in bump if your running lowered and operating at lower ride heights. At stock ride heights standard tie rod ends would be better I think. I don’t think it is worth shimming the NB rack if you run the LE tie rod ends. NA knuckles on an NB subframe produces way too much bump steer correction and screws things up.
With all NB Subframe NB knuckles, and LE tie rod ends I only get about 1/16” tow out from ride height to full bump. And 7/8” of total tow in at full shock extension. Meaning very little bump steer from around nominal ride height to full bump for lowered suspension setup and what little bump steer there is is in the right direction for stability.
I suspect NB with standard tie rod ends might tow in a bit at full bump and running the le tie rod ends is a little better for the suspension kinematics in bump if your running lowered and operating at lower ride heights. At stock ride heights standard tie rod ends would be better I think. I don’t think it is worth shimming the NB rack if you run the LE tie rod ends. NA knuckles on an NB subframe produces way too much bump steer correction and screws things up.
#31
Now I don't have to wonder, just procrastinate as I have with the Mini dynapro kit for close to 10 years.
Haven't this combo been used on Spec Pinata since they allowed NB-subframes on all (just wondering)?
#32
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Nb knuckles
LE or NA- R-package tie rod ends.
Based on my measurments I think this is a good setup if you oporate on a lowered suspension that frequently uses all the bump travel as most of the fastest track cars have their setup. I think trying to correct it even more than LE tie rod ends do is too much.
#33
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I've been wondering about that combo for some time but have been too lazy to order some LE rod ends and measure.
Now I don't have to wonder, just procrastinate as I have with the Mini dynapro kit for close to 10 years.
Haven't this combo been used on Spec Pinata since they allowed NB-subframes on all (just wondering)?
Now I don't have to wonder, just procrastinate as I have with the Mini dynapro kit for close to 10 years.
Haven't this combo been used on Spec Pinata since they allowed NB-subframes on all (just wondering)?
#37
I bought THESE labeled as aftermarket LE tie rod ends. I ended up having to return them because of clearance issues with 949s 11.75" BBK on NA spindles. I had the same problem as Dcamp2 on this board.
I haven't measured them to confirm they are in fact LE/R package copies, just confirmed they wouldn't work for my application
Note that on Parts Geek and CARid, these are listed as specifically compatible with 1993 and 1994 Bilstein equipped cars.
First equipment quality PN# 8535-01118326
I haven't measured them to confirm they are in fact LE/R package copies, just confirmed they wouldn't work for my application
Note that on Parts Geek and CARid, these are listed as specifically compatible with 1993 and 1994 Bilstein equipped cars.
First equipment quality PN# 8535-01118326
#39
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I bought THESE labeled as aftermarket LE tie rod ends. I ended up having to return them because of clearance issues with 949s 11.75" BBK on NA spindles. I had the same problem as Dcamp2 on this board.
I haven't measured them to confirm they are in fact LE/R package copies, just confirmed they wouldn't work for my application
Note that on Parts Geek and CARid, these are listed as specifically compatible with 1993 and 1994 Bilstein equipped cars.
First equipment quality PN# 8535-01118326
I haven't measured them to confirm they are in fact LE/R package copies, just confirmed they wouldn't work for my application
Note that on Parts Geek and CARid, these are listed as specifically compatible with 1993 and 1994 Bilstein equipped cars.
First equipment quality PN# 8535-01118326