Wheels and Tires All things related to Miata Wheels and Tires.
Sponsored by:
Sponsored by:

Fitting 275 Hoosiers on an NB with offset upper bushings

Thread Tools
 
Search this Thread
 
Old 03-06-2014, 08:44 AM
  #21  
Elite Member
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,479
Total Cats: 104
Default

Dont you know, you need all of the steering angle to drift with 275s.*






*not really, just put heat cycled out Rs on the back and decent As on the front and it'll drift with just gentle caresses on the steering wheel
Leafy is offline  
Old 03-06-2014, 12:12 PM
  #22  
Elite Member
 
bbundy's Avatar
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
Total Cats: 144
Default

Originally Posted by codrus
What are your concerns about the V8R arms? How would you modify the stock ones? Just lengthen them by some fixed amount and lose the extra adjustment or would you put the eccentric bolt in as well?

I have the RB 1.25" sway bar and even the 225s crash into it at full lock, so yeah I don't expect to get the 275s that far over. Fortunately I don't have to parallel park the car at an autox.

--Ian
I think mine are like their 4th redesign due to strength issues they had. I still don’t like some of the geometry and weld locations they have for attaching the outer end plate metal parts onto the large round tubing. I believe they have some fairly substantial load paths going through short sections of weld on tube walls. Looks like they got all the strength issues sorted but still may have some longer life fatigue issues yet next to some key welds.

My original thought on the stock ones was to just move the holes. But after having the V8R ones I come to realize the benefit of having the outer adjustment if you ever want to do any self-alignment with primitive tools so I might would try and get the cam bolt features incorporated.

That outer cam bolt and the other bolt both need to be tight as hell because with that much grip they tend to slip. Probably a good Idea to use higher strength steel like 4130 for the hole slots to keep from yielding it under the washer with repeated use.
.
bbundy is offline  
Old 03-06-2014, 02:57 PM
  #23  
Elite Member
 
bbundy's Avatar
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
Total Cats: 144
Default

Originally Posted by Savington
Whining about how your 275s hit your _________ at full lock makes you a tremendous baby. Just FYI
Hitting the tire on the sway bar at full lock isn’t a concern. just nice to have it go away completly. Having the A-arm machine away the rim lip within a few revolutions at full lock I think is an issue and should be addressed with some steering stops if you have that situation. 10’s with no spacer will just kiss the rim lip on stock A-arms at full lock. 11’s would have about ½” of interference.
bbundy is offline  
Old 03-06-2014, 02:58 PM
  #24  
Former Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 15,442
Total Cats: 2,099
Default

Or you could just not use full lock, like I've done in every Miata I've driven since 2007
Savington is offline  
Old 03-06-2014, 04:35 PM
  #25  
Elite Member
Thread Starter
 
codrus's Avatar
 
Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 5,166
Total Cats: 855
Default

Originally Posted by bbundy
Hitting the tire on the sway bar at full lock isn’t a concern. just nice to have it go away completly. Having the A-arm machine away the rim lip within a few revolutions at full lock I think is an issue and should be addressed with some steering stops if you have that situation. 10’s with no spacer will just kiss the rim lip on stock A-arms at full lock. 11’s would have about ½” of interference.
9s will contact the A-arm at full lock if you have the offset upper bushings. At least, they will if you have the steering rack one spline off-center the way I do (I really ought to fix that one of these days).

I've done it a few times when maneuvering the car onto the trailer, and it's not that big a deal. It does scar up the painted edge of the rim, but it's not going to destroy anything as long as you don't hold it there.

From a conversation I had elsewhere, it sounds like most CSP Miatas have offset bushings and 15x10s with a spacer, so maybe there's hope there yet. I guess I just need to find some more wheels.

--Ian
codrus is offline  
Old 04-13-2014, 11:11 AM
  #26  
Elite Member
iTrader: (15)
 
ZX-Tex's Avatar
 
Join Date: Dec 2007
Location: San Antonio, Texas
Posts: 4,847
Total Cats: 27
Default

FWIW it is easy to make steering rack stops from a piece of SCH-40 PVC pipe (2" IIRC). Takes less than 30 minutes to fab and install. Easy peasy.
ZX-Tex is offline  
Old 04-13-2014, 03:00 PM
  #27  
Senior Member
iTrader: (6)
 
k24madness's Avatar
 
Join Date: Jun 2010
Location: San Rafael, CA
Posts: 1,421
Total Cats: 95
Default

Originally Posted by bbundy

My original thought on the stock ones was to just move the holes.
I have a solution that should work well. It involves moving the ball joint out 1/4"-3/8". If my math is correct that's about .5 to .75 degrees of camber. More that enough IMHO.

I will send you some pics if you want to take the same approach.
k24madness is offline  
Old 04-13-2014, 10:24 PM
  #28  
Elite Member
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,479
Total Cats: 104
Default

Still having a strugglefest here myself. I finally have some sticker hoosiers, wow theres a lot more rubber here than the scrubs I've been buying. I added packers until it didnt rub at the stock height xida bump stops. That resulted me being on the bump stop before even hitting static ride height. Took the 1/4 of a bump stop I had left over from making the rears match emilio's installation instructions and put that in with a spacer. I'm at ~5/8" of bump travel now with it setup to not destroy the tire on shock tower, AND also a 6mm spacer making my total offset +13. Any more than +13 and it will rub significantly on course on the back of the wheel well. If I went to like +6 offset then it would clear the shock tower and I'd be able to run over 1.5" of bump travel. I'm beginning to think my car is more bent that originally thought, lol.
Leafy is offline  
Old 04-22-2014, 06:19 PM
  #29  
Elite Member
 
bbundy's Avatar
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
Total Cats: 144
Default

Originally Posted by ZX-Tex
FWIW it is easy to make steering rack stops from a piece of SCH-40 PVC pipe (2" IIRC). Takes less than 30 minutes to fab and install. Easy peasy.
I may have to do this. the 11" wheels hit the 2.25" ID springs before full wheel cut. Rubs through the powder coat real fast.
bbundy is offline  
Old 04-22-2014, 09:29 PM
  #30  
Elite Member
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,479
Total Cats: 104
Default

Originally Posted by bbundy
I may have to do this. the 11" wheels hit the 2.25" ID springs before full wheel cut. Rubs through the powder coat real fast.
But even with the 10" wheels they rub on the springs, just enough to take the powdercoat off.
Leafy is offline  
Old 04-22-2014, 10:44 PM
  #31  
Elite Member
iTrader: (15)
 
ZX-Tex's Avatar
 
Join Date: Dec 2007
Location: San Antonio, Texas
Posts: 4,847
Total Cats: 27
Default

Originally Posted by bbundy
I may have to do this. the 11" wheels hit the 2.25" ID springs before full wheel cut. Rubs through the powder coat real fast.
Mine are rubbing on my swaybar. Anyway it is a really easy fix. I think there is a thread about it somewhere around here. I might be wrong on the PVC diameter, but essentially you just cut the pipe to the length you need for the bump stop, cut out about 1/4-1/3 of its circumference so it is c-shaped, pull off the inside end of the tie rod boot, clip the pipe onto the rack, put the boot back, done. The pipe hits the inner tie rod on one end and the rack housing on the other, shortening the rack travel. Add the spacers on both sides obviously. Works great. Only disassembly required is pulling back the boot, which is easy.
ZX-Tex is offline  
Old 04-29-2014, 07:57 AM
  #32  
Newb
 
1999monster's Avatar
 
Join Date: Jan 2013
Posts: 6
Total Cats: 0
Default

I'm new to this, can some one quickly explain the offset bushing, or post a pic of what it looks like?

Thanks
1999monster is offline  
Old 04-29-2014, 08:15 AM
  #33  
Elite Member
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,479
Total Cats: 104
Default

Originally Posted by 1999monster
I'm new to this, can some one quickly explain the offset bushing, or post a pic of what it looks like?

Thanks
The hole in the bushing is drilled offset.
Leafy is offline  
Old 04-29-2014, 10:34 AM
  #34  
Elite Member
iTrader: (5)
 
Seefo's Avatar
 
Join Date: Dec 2010
Location: Raleigh, NC
Posts: 1,961
Total Cats: 48
Default

Originally Posted by 1999monster
I'm new to this, can some one quickly explain the offset bushing, or post a pic of what it looks like?

Thanks
https://www.google.com/search?q=offs...w=1432&bih=942
Seefo is offline  
Old 04-29-2014, 12:13 PM
  #35  
Elite Member
Thread Starter
 
codrus's Avatar
 
Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 5,166
Total Cats: 855
Default

Offset bushings allow you to effectively shorten (or lengthen, but there's little reason to do that) the upper A-arm, by moving the pivot point closer to the upper ball joint. There are some useful photos in the ISC installation instructions.

--Ian
codrus is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
84
04-12-2021 04:21 PM
emilio700
Wheels and Tires
151
06-02-2017 02:36 PM
Quinn
Cars for sale/trade
6
10-23-2016 07:58 AM
mx592
Suspension, Brakes, Drivetrain
1
10-01-2015 12:45 AM



Quick Reply: Fitting 275 Hoosiers on an NB with offset upper bushings



All times are GMT -4. The time now is 12:47 AM.