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Discussion Starter #1 (Edited)
There's been a couple recent requests for an updated stock class setup thread, so I figured I'd give it a go. The old FAQ still has some great info. This thread should be used in conjunction with the FAQ: http://web.mitsi.com/autocross/faq.html

Tires: Kumho V710s and Hoosier A6s are the hot ticket now. Both are available in 205 and 225 in 14" and 15" diameters, but the Hoosier 15" is a 225/45/15 while the Kumho is a 225/50/15, making the Hoosier an inch shorter (22.9" OD vs. 23.9" OD). 14" options are about the same size. Some folks have had success in ES running the Kumho 205 on all four tires where the extra acceleration is beneficial. Since the rear wheels are 7" and the fronts are 6", you still get a little stagger based on how the tire fits the wheel. Kumhos seem to like less pressure (low to mid 30s). Hoosiers tend to like a little more (low 40s).
Kumho website
Hoosier website

Both are available at Tire Rack

2nd tier tires include:
Kumho Victoracers
Hankook Ventus Z214
Toyo Proxes RA1
Hoosier R6 (harder road race compound)

Wheels
91/92
Very few wheel options are available for 91/92 cars. Most people have resorted to custom wheels or just run stock alloys. Circle Racing doesn't exist anymore. Spin Werkes owns their old molds and is making similar wheels. Many folks have had issue with the old Circle wheels bending. Available from Racer Parts Wholesale for about $900/set. (WILL NOT FIT THE FRONT OF A TURBO due to brake clearance issues.) Kodiak may be another option.

93+
Wheels from the 95-96 Mazda Millenia (9-spoke alloy) and 93-95 929 (11-spoke alloy) fit the front and are nice and light, in the neighborhood of 10-11#. They have a deeper offset and require 10mm spacers (might be 11mm) to push them out to max offset (so you can get max camber). They also require conical lug nuts like most alloy/tuner wheels.

For the rear, SSR Competitions and Volks are the pricey options but weigh under 10#. Kosei K-1s are another option, slightly heavier, but half the price. Koseis are also slightly outside of the offset limits, and need the hub face milled to truly be legal. There are other options out there as well.

Max legal offset is 38.65mm for all MK2s.

Alignment
Front:
Camber: Max negative (-2.5 to -3.0 degrees) using crash bolts
Caster: Max positive (5.0 degrees), only adjustable on 91/92 cars
Toe: 0 to 1/8" total toe OUT, provides crisper response and turn-in

Rear:
Camber: Max negative (-1.5 or so) crash bolts NOT LEGAL
Toe (91/92): 0 to 1/8" total toe IN is a good place to start
Toe (93+): 0" is a good place to start

Crash bolts are smaller diameter bolts that fit in the lower clevis holes in the strut where the strut connects to the upright/knuckle. Per Toyota Technical Document Volume 10, number 007 (referenced from old FAQ) these bolts are legal to run in the FRONT ONLY of an MK2 MR2. These bolts work by creating extra "slop" in the suspension and allowing more camber adjustment. Torque specs are in the 200 ft-lb range. Many people have experienced slipping camber during events. Always use new bolts and nuts, torque them to spec, and don't be afraid to rough up the mating surface on the strut housing (not the upright).

Crash bolt part numbers:
Large 90105-15004
Med 90105-15005
Small 90105-15006 <-- you want these for max camber
Nuts 90179-15001

Struts
Most MK2s have struts that can be replaced with a cartridge/insert. Some 94-95 require cutting. You can check to see if your struts accept inserts w/o cutting by checking for a gland nut at the top of the strut body (inside the spring, probably covered by a rubber dust cover).

Koni Sport
Konis are the popular choice, and the most expensive of the OTS units. They are a drop in cartridge. The primarily adjust rebound via a single adjuster, have a wide range of analog adjustment (no clicks). You normally adjust by starting at one end of the range and count turns. Full range is usually 2.5 turns on fronts, 1.5 or so on rears.

Tokico Illumina
A cheaper option, but not as stiff as the Konis. These supposedly adjust both rebound and compression simultaneously, and have a single adjuster with 5 settings.

KYB AGX
Also cheaper than the Koni, but very stiff. Might work well depending on how smooth the lot is you are on. Not nearly the range of the Koni. Single adjuster with 4 settings.

Front Sway Bar
Upgrade to 93+ endlinks or Twos-R-Us endlinks to keep them from bending. Also, reinforce the endlink tab on the strut by welding a plate over the face that extends up to the lower spring perch. These tabs break by snapping, pulling the whole tab off the housing, or tearing the bolt hole. This method helps prevent all three. 91/92 cars also have smaller bolts attaching the sway bar to the chassis. ST makes reinforcement plates that I believe Twos-R-Us is stocking now. Otherwise they are only available with the purchase of an ST sway bar.

ST
The ST bar is the current standard. It's the biggest/stiffest available OTS. It used to be solid but I've heard rumor they're now hollow. Old ones are painted grey, rumor says new ones are green. Not adjustable. It comes with brackets and bushings. Most folks modify the bar by extending the end tabs a few inches and adding more holes so it can be adjusted softer. Can be purchased almost anywhere: stranoparts.com, Twos-R-Us, shox.com, etc.

Addco
This was a recent discovery in the community. This bar falls right between the ST and TRD bar in stiffness and seems to be a nice fit for some folks. It's solid, also not adjustable, gold in color, and can be found at stranoparts.com.

TRD
This bar used to be the standard, but has become the lightweight of the bunch. Still stiff enough to get the job done, but not as strong as the other two. It is hollow, not adjustable, and white in color.

Engine/Power
Air filters and cat-backs seem to do very little for the NA car. A straight pipe is a nice option to help lose 30+ lbs in stock muffler, and add a nice tractor sound. Same goes for the turbo car. Lose the muffler to lose the weight, but don't expect big power gains in this area.

Stock plugs and wires are plenty sufficient. On the turbo car, make sure you're getting max boost per the factory service manual. An aftermarket boost gauge is a good way to monitor this. Stock gauge sucks.

Brakes
I've always been a huge fan of stock brake pads. Some folks swear they need more rear bias and put a race pad in the back. Porterfield R4S's seem to be popular here. Carbotech is another brand I've heard used. If you don't have ABS, I wouldn't bother upgrading the fronts, and only do the rears if you definitely feel like you're locking up the front tires way too early.

Options/Models
It's been claimed that certain years and options are superior. Driven right, any year MK2 can win. If you're searching for a car, the 93+ models have the advantage of 15" wheels and a slightly lower ride height. Sunroof cars tend to have less head room. A zero option fully prepped ES car can get down to about 2400#. Most ES cars are between 2500-2600 in fighting trim. BS turbos tend to be 100 lbs or so heavier.
 

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Randy,
how about some pointers on how to setup Street Prepared or SM2 suspensions? I'm especially interested on how camber/caster settings should be changed from stock autox settings once you have stiffer springs or swaybars.
 

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Discussion Starter #6
velandia said:
Randy,
how about some pointers on how to setup Street Prepared or SM2 suspensions? I'm especially interested on how camber/caster settings should be changed from stock autox settings once you have stiffer springs or swaybars.
Once I figure it out I'll post ;)

We'll save that for another thread.
 

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Thanks Randy. Miscellaneous notes/suggestions follow.

* Suggest adding Hoosier R6 to 2nd tier tire list.
* AFAIK, no one has run seriously with 205s on the rear of a BS car. ES, yes.
* Do people really run V710s under 30 psi? I never heard that. I was at 34/38 on my Turbos and low forties for Hoosiers, but those were S04s.
* Circle Racing doesn't exist as such, anymore. Spin Werkes owns their old molds, though, and is making essentially the same wheel. Available from Racer Parts Wholesale for about $900/set. WILL NOT FIT THE FRONT OF A TURBO due to brake clearance issues.
* I believe Kodiak will be happy to make you stock-legal 14s for about $1200 or so.
* Max legal offset is 38.65mm for all mk2s.
* Regarding alignment, many people are running zero toe ( front and/or rear ) even on early cars. Suggest increasing the ranges to reflect that.
* Replace crash bolt nuts with the bolts ( p/n 90179-15001 ).
* All mk2s have struts that can be replaced with a cartridge... the problem is, some 94+ require cutting and re-welding, versus simply unscrewing the gland nut on the earlier cars.
* Full adjustment range on the rear Konis is less than 2 turns, usually about 1.5.
* I don't see how a hardtop can have more headroom that a T-top car, even with the tops in. Maybe a mm or two... how thick is the T-top, compared to the roof+headliner?
 

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hillman said:
* I don't see how a hardtop can have more headroom that a T-top car, even with the tops in. Maybe a mm or two... how thick is the T-top, compared to the roof+headliner?
Yes, where the glass is, the t-top has more room. However, at the edges, the ceiling sits lower. Same goes for the thicker part above the side window.
 

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rnoll89 if you want to update the FAQ, just download it, update it and send it to me and I will post it.
If you have trouble downloading it, let me know and I'll zip the site up and send it too you.
 

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I had a set of Kodiak on my 93T before. (Waited 12 weeks) and ran 225/45/15 A6 on them. I had a suspicion that it might fit the front ( because I accidentally put them on in the garage). I spined it around and didn't hit anything. However I did not run them on the street/autox, because at the time my studs were too short to hold them in.

However those were mounted on the 7" wheel (with almost max back spacing to make them stock legal) so 6" might be a different story.
 

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JSmdshp909 said:
randy helpful sticky but can recommend shock settings? for the tokicos and konis
More in front, less in back. Come out to California Speedway Sunday (SCCA info at solo2.com) and look me up. White MR2, big white trailer.

Eric
 

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Discussion Starter #17
ewcmr2 said:
More in front, less in back. Come out to California Speedway Sunday (SCCA info at solo2.com) and look me up. White MR2, big white trailer.

Eric
This is what I also ran. Though I had heard that some folks were running softer up front to compensate for the bigger bar. A wise autocrosser once told me shocks are tuned based on driver preference, not necessarily within a set window like other things. Which makes sense, shocks do just that, absorb shock. If you're super smooth, you can usually get away with stiffer shocks. If not, a softer setting will disrupt the tires less when unsmooth inputs are made.
 

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ewcmr2 said:
More in front, less in back. Come out to California Speedway Sunday (SCCA info at solo2.com) and look me up. White MR2, big white trailer.

Eric
o really ive never seen you before hopefully i get into this practice this saturday
i wouldnt mine getting some tips and advice into competing cause im just doing the practices for fun. but i modded my car too much and i have a turbo i wish i can start off with n/a mk2 cause bstock is hardcore :(
 

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You might consider revising the weights for the turbo cars.

I would suggest:

2650 fully prepped (no AC, light wheels, no PS, manual everything, etc.)

I think your average car (still has AC, PS, PW, but no muffler, lighter wheels etc.) will weigh just under 2800. My 93 t-top weighed 2830 and my 91 sunroof weighed 2800, both with stock wheels, no muffler, and t-tops/sunroof, spare, jack, floor mats, all removed.
 
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