MR2 Owners Club Forum banner

1 - 18 of 18 Posts

·
Registered
Joined
·
721 Posts
Discussion Starter · #1 ·
What would be a good allignment for my car. i have 4 way shocks and eiabach springs. my rims are 17.5 front and 18x8 rear. im looking for somethin more balance when entering the corner. thanks.
 

·
Two 2s - 93T, 88 SC
Joined
·
2,966 Posts
What is your balance now ? Are you understeering or oversteering ? Do you know your current alignment ? Do you have stock sway bars ? What size and type tires do you have ? What do you have your shocks set to ? Do you have Pro-kits or Sportlines ?

John
93T, 88 SC
 

·
Registered
Joined
·
4,054 Posts
The suggestions for autocross use are not going to work well for this guy. First of all, I doubt he can get anywhere close to -2.5? in front, with those 17s... unless they really are only 5" inches wide, but I don't think that's what he meant. Also, he better have power steering if he's going to max out the caster on those big front tires.

More importantly, the autocross FAQ suggestions are for autocross use... they will not be what most people want for street use.

If the OP answers some of John's questions, we can probably help a bit more. If the OP can't or doesn't, then I'd just tell him to stick close to the OEM alignment specs.
 

·
Registered
Joined
·
721 Posts
Discussion Starter · #5 ·
What is your balance now ? Are you understeering or oversteering ? Do you know your current alignment ? Do you have stock sway bars ? What size and type tires do you have ? What do you have your shocks set to ? Do you have Pro-kits or Sportline


Sorry about the rims there 17x7.5 in the front. it is understeering. i dont know the alignment. i have the stock sway bars. i have 215/40/17 front and 235/40/18 rear. there Azenis ST-115. the shocks are set at 3 all around right now. they are pro kit springs.
 

·
Registered
Joined
·
4,054 Posts
Assuming you don't have a problem attributable to an incorrect alignment ( off-center steering, uneven tire wear, poor tracking )... the first thing I would do to get the car to turn-in without understeer is soften the front shocks.

Without knowing the current alignment, it is tough to say what you might want to change there. Normally, some additional negative camber in the front would help, but as I said, you may not be able to get much more with those big fronts. Around here, we have Just Tires and a few other places that'll do a free alignment check. For nothing, you should get a print-out from their rack showing your current alignment. That'd be a good first step if you do want to tune the handling that way.

I'd try the shocks, first, though... you bought adjustable ones, so you may as well get your money's worth, right?
 

·
Registered
Joined
·
548 Posts
hillman said:
The suggestions for autocross use are not going to work well for this guy. First of all, I doubt he can get anywhere close to -2.5? in front, with those 17s... unless they really are only 5" inches wide, but I don't think that's what he meant.
For the record, I just my alignment re-done yesterday and was surprised with the results - pretty much what I wanted/asked for!

I have 17" x 7" front wheels with 215/40-17 tires; car is lowered on H&R Sport springs, and with TEIN front pillow mount/camber plates (no crash bolts) my alignment guy squeezed out 2.4 degrees of negative camber up front, and 4.6-4.8 degrees of caster. I set the toe at zero.

On the rear, I'm at .09" toe-in per side, and 1.6 degrees negative camber (with eccentric cammed lower strut pinch bolts).

I have an autox event this weekend and I hope the car's settings sort of work!
 

·
Registered
Joined
·
2,290 Posts
In case others haven't noticed, blckmr2gts has a 93T. His castor isn't adjustable and he should not use the 91-92 rear toe spec.
 

·
Registered
Joined
·
548 Posts
twoina2 said:
In case others haven't noticed, blckmr2gts has a 93T. His castor isn't adjustable and he should not use the 91-92 rear toe spec.
I certainly didn't notice, since he didn't bother to post it in the thread. Also, I'm pretty sure he's not paying attention to this thread anymore anyway.

My main point was that it is certainly possible to get 2.5 degrees of negative camber up front with 17" wheels without rubbing (even with the car lowered substantially). I actually had 2.6 degrees on the right side before the alignment tech evened it out.

I thought volunteering this information might be useful to others who are researching MR2 alignments for autox use (as I was - that's how I found this thread in the first place).
 

·
Registered
Joined
·
193 Posts
alignment specs

Best way to set up an alignment for your car would be to go to the alignment shop and talk with your mechanics. I do alignments all day, and it is kinda of a form of magic. My machine and books give me specs, but you never know how a car is really going to react to a certain track. Best to just understand what chages in alignment cause what changes in driving, and start close to spec, slowly adjusting from there. Usually i bring the left caster .5 degrees more neg than the right, but that is to accomodate for the drainage grade of most public streets. The More neg your caster, the more your car is going to want to oversteer. Don't forget that the car pulls towards the side with the most neg (or least total) caster. Usually the steering gets easier as caster gets neg also. camber is usually set to spec for the street, but riding more neg camber allows the car tires to go level when the car is squatting under extreme cornering. I enjoy the rear end of my car swiinging looser that the front, so I keep rear camber a little more neg on the front. As far as toe, I always stick with spec. It is really hard to just tell someone what is best for their car, and since alignments aren't cheap and easy, I would suggest talking with the tech at the shop, since he will give you better work and not bitch so much about realignments if he is part of the descision making. No one wants to be told exactly how to do their job, especially when there's a good chance you'll need another align soon! Hope this helps!! If you live in east tn, elizabethton area, call me at the shop 423-543-4411, and I'll get those alignments done at a cheap rate! I just love mr2's so any mr2 owner gets a great deal by me!!! :thumbup
 

·
Registered
Joined
·
548 Posts
There is one point of confusion with the things you're saying.

shanesublett said:
The More neg your caster, the more your car is going to want to oversteer. Don't forget that the car pulls towards the side with the most neg (or least total) caster. Usually the steering gets easier as caster gets neg also.
You're half right. POSITIVE caster means line from the lower control arm point to the upper control arm point (the ball joints actually, but close enough) leans back, like the rake of the windshield. This adds "camber on demand" as the wheel is turned, which gives more grip up front, which would tend to give you more oversteer characteristics, all else being equal.

As caster increases, steering effort goes up, so as caster decreases - i.e., goes more negative - steering effort will go down (as you stated).

http://stockcarracing.com/tipstricks/31519/

I've never seen a car with negative caster by design though - it would make the car extremely unstable and there would be no self-centering to the steering at all.

shanesublett said:
As far as toe, I always stick with spec.
If you want minimal tire wear, especially if you do have more negative camber than OEM spec, I would suggest that zero toe (dead straight ahead) would be best for street driving. The OEM spec is typically toed in a little for better stability and tracking.

shanesublett said:
I would suggest talking with the tech at the shop, since he will give you better work and not bitch so much about realignments if he is part of the descision making. No one wants to be told exactly how to do their job, especially when there's a good chance you'll need another align soon!
I respectfully disagree. While you seem to know what you're talking about, most alignment "techs" at shops don't understand fundamental vehicle handling and suspension design - they just get the alignment machine to read within spec. They don't like being told otherwise, and like all people, they're uncomfortable with new ideas and new procedures they're not used to.

You're right, no one likes to be told how to do their job, but if they work in a service industry, it's par for the course. If the shop/tech doesn't understand why you want alignment settings that aren't within OEM specs, or why you want to sit in the car while they align it, go somewhere else.

Find out where autocrossers and track-day drivers take their car for alignments. Unfortunately, there will be very few alignment racks/techs that cater to performance drivers, but its worth looking for the right shop.

Finally, TIP your alignment tech if they get it right! In fact, now that I have a regular tech that does my cars, I tip them before they start.
 

·
Registered
Joined
·
193 Posts
oversteer

:thumbup Perhaps my understanding of under and oversteer are wrong. Isn't oversteer when you turn a little and get a lot? I was under the impression that the car tends to steer faster and more unpredictably as you bring the front tires towards the rear, or more under the center axle. if you could verify the truth for me, I'll be sure and retain it.

Never be scared to tell your tech exactly what you want! I am a tech, and I understand that your money is your money!! If you ask for out of spec work, you may be questioned as to why (I only verify because some people really don't know what they are asking for!), but with the mention of race, what you say is what you get. You'd be surprised how many doctors turn mechanic when the car acts up!!! Be leary of the mechanic that thinks it's his car your paying to have worked on!
 

·
Registered
Joined
·
2,379 Posts
my tire size is the same but i dont have adjustable shocks. my alignment is:
-1.5? both front and rear and toe out 1/16"
when i do things rite it feels pretty solid although i wish i could've gotten a little more camber up front (i wanted -2?). i also have mixed tires, i have yokohama es100 up front(215-40-17) and falken grb 451 in the rear(235-40-17).
 

·
Registered
Joined
·
4,054 Posts
My main point was that it is certainly possible to get 2.5 degrees of negative camber up front with 17" wheels without rubbing (even with the car lowered substantially). I actually had 2.6 degrees on the right side before the alignment tech evened it out.
I thought volunteering this information might be useful to others who are researching MR2 alignments for autox use (as I was - that's how I found this thread in the first place).
This is good to know, but I just want to add that it makes a big difference that you're using camber plates, instead of crash bolts. That allows the top of the strut to lean in, and give you more room for 17s.
 

·
Registered
Joined
·
548 Posts
shanesublett said:
:thumbup Perhaps my understanding of under and oversteer are wrong. Isn't oversteer when you turn a little and get a lot? I was under the impression that the car tends to steer faster and more unpredictably as you bring the front tires towards the rear, or more under the center axle.
You've got oversteer and understeer right. You just had flip-flopped the conventional interpretations of positive and negative caster. All I was saying is that as caster goes more POSITIVE (ie the front wheels move AWAY from the rear ones, if the upper ball joint position stays the same), you get more added negative camber on the outside front wheel as you turn the steering wheel, which tends to give more grip up front, and therefore less understeer or more oversteer.

You had posted "the more neg your caster, the more your car is going to want to oversteer." It's actually "the more POSITIVE your caster, the more your car is going to want to oversteer" (but only when you've got the wheel turned a significant amount).

Hillman, good point about the difference in clearance obtained by camber plates vs. crash bolts. Thanks for making that clear.
 

·
Registered
Joined
·
269 Posts
does anybody know the stock alignment specs for 91turbo? Any better specs for street driving.

TP
 

·
Registered
Joined
·
2,290 Posts
Stock Alignment specs per '91 bgb -

Ft. camber - -1.0 deg +- 1/2 deg, 1/2 deg max left-right error
Caster - 2.75 deg +- 1/2 deg
Ft. Toe - .04" +- .08" (total, measured @ tread)
Rr. Camber - -1.3 deg +- 1/2 deg, 1/2 deg max left-right error
Rr. Toe - .20" +- .04" (total, measured @ tread)

Afaik, these are the same as the 93+ specs except that the 93+ cars have a revised rear suspension which allows less rear toe.

I like zero front toe and minimal rear toe. More camber, say 1/2 degree more, helps cornering and doesn't increase tire wear that much. Max. caster is good provided you have power steering and don't run optimal static camber (you don't). The factory allows +-1/2 degree. I start to fuss at +-1/8 deg and do it over if it is more.

Mike R
 
1 - 18 of 18 Posts
Top