I'm conflicted on coilovers

[wparsons]

Originally Posted by 86TX

I do plan on tracking the car but not while Im in warranty(5 more years lol) but how long until those tein flex z's bottom out on the threads? like is there a lot of gap or what? I want them to be damn near close to tucking my tyre lol


Sent from my iPhone using Tapatalk

At that ride height, it's going to handle like crap without lots of geometry correction. You'll need about $2.5k in parts other than the coilovers for it to handle like it should at that low of a ride height.

Why wait for warranty to expire before tracking it? Tracking it won't void your warranty.

[Ashikabi]

Originally Posted by wparsons

At that ride height, it's going to handle like crap without lots of geometry correction. You'll need about $2.5k in parts other than the coilovers for it to handle like it should at that low of a ride height.

Why wait for warranty to expire before tracking it? Tracking it won't void your warranty.

I'm tucking tire on my 18s and did not need 2500$ in parts. I also autocross it without issue.

[nikitopo]

I guess they don't care about handling, just the looks ...

[wparsons]

Originally Posted by Ashikabi

I'm tucking tire on my 18s and did not need 2500$ in parts. I also autocross it without issue.

Without issue, or with better handling than stock? What geometry correction have you done? How well do your times compare to a bone stock FRS/BRZ on similar tires?

With a 2" drop you'll need pretty substantial geometry correction to not be handling worse than stock.

I'm not suggesting the car will fall apart or explode, but it will definitely handle worse than stock.

[Ashikabi]

Originally Posted by wparsons

Without issue, or with better handling than stock? What geometry correction have you done? How well do your times compare to a bone stock FRS/BRZ on similar tires?

With a 2" drop you'll need pretty substantial geometry correction to not be handling worse than stock.

I'm not suggesting the car will fall apart or explode, but it will definitely handle worse than stock.

I run -3.5 front and -2.5 rear to deal with my tires rolling over. Stock toe. My rear wheels looked off center(front to back) in the wheel well so I got adjustable trailing arms and went to the shortest setting. No one can measure rear caster so I don't know what it's set at. Rear LCA, toe and caster(trailing) arms, front camber bolts. I haven't raced on my Fortunes yet(this weekend) but my Stance coils got me similar times to the other twins with pleb drivers. There is one local who posts some of the best times in the class/all classes in an frs but he races every weekend(track or autocross) and I race 5or 6 times a year. I blame my middle of the road times on being a bad driver, not the car. I did my suspension mods and tires at the same time after a season so I didn't have a good comparison between how it handled stock, and how it handles now. I'm not saying it's better than stock, I'm just saying you don't need $2500 in "other"parts to make it handle decent

[smg1138]

Since we're on the subject, how far can you lower before geometry correction becomes necessary? I think I've heard about 30mm somewhere, but wasn't sure how true that was.

[Ashikabi]

Originally Posted by smg1138

Since we're on the subject, how far can you lower before geometry correction becomes necessary? I think I've heard about 30mm somewhere, but wasn't sure how true that was.

That's about right. I think that's just for camber correction though, it's lower before you need toe correction in the rear I think.

[smg1138]

Originally Posted by Ashikabi

That's about right. I think that's just for camber correction though, it's lower before you need toe correction in the rear I think.

I was talking more about bump steer correction. I know after a certain point bump steer correction needs to be made via longer ball joints.

[Lynxis]

1 inch lower than stock is safe and it sounds like 1.2 inches lower seems to be the limit of what you can get away with before you need to seriously think about bump steer and roll centre correction. I know at 1.5 inches lower that bumpsteer and roll centre correction are highly recommended.

I will also note that it's well known that lowering our cars contributes to premature wear in the CV joints in our axles. Lowering much more than 1 inch and you should look at subframe and diff risers or DSS axles so you aren't killing them constantly.

[Ashikabi]

Originally Posted by smg1138

I was talking more about bump steer correction. I know after a certain point bump steer correction needs to be made via longer ball joints.

Bump steer I've never looked into, I can't say I've "felt"it pull when hitting a bump but I'll look into it

[nikitopo]

Suspension is designed to lower max. 20mm without changing geometry (dynamic alignment). A lowering of 30-35mm is not optimal but OK. Personally, I wouldn't lower more than 15mm.

Reference here: http://www.ft86club.com/forums/showp...5&postcount=11

[wparsons]

Originally Posted by Ashikabi

I run -3.5 front and -2.5 rear to deal with my tires rolling over. Stock toe. My rear wheels looked off center(front to back) in the wheel well so I got adjustable trailing arms and went to the shortest setting. No one can measure rear caster so I don't know what it's set at. Rear LCA, toe and caster(trailing) arms, front camber bolts. I haven't raced on my Fortunes yet(this weekend) but my Stance coils got me similar times to the other twins with pleb drivers. There is one local who posts some of the best times in the class/all classes in an frs but he races every weekend(track or autocross) and I race 5or 6 times a year. I blame my middle of the road times on being a bad driver, not the car. I did my suspension mods and tires at the same time after a season so I didn't have a good comparison between how it handled stock, and how it handles now. I'm not saying it's better than stock, I'm just saying you don't need $2500 in "other"parts to make it handle decent

If you've added camber and coilovers and it handles worse than stock, I think by definition it doesn't handle decently. With the camber alone it should handle better than stock.

Originally Posted by Ashikabi

That's about right. I think that's just for camber correction though, it's lower before you need toe correction in the rear I think.

That's not geometry correction, that's just alignment. I was talking about bump steer and roll center.

[Ashikabi]

Originally Posted by wparsons

If you've added camber and coilovers and it handles worse than stock, I think by definition it doesn't handle decently. With the camber alone it should handle better than stock.



That's not geometry correction, that's just alignment. I was talking about bump steer and roll center.

Again, I can't tell you if it handles better or worse because I don't have a good way to make an objective judgement on it. My mistake on the roll center and bump steer. Whiteline offers tie rod ends to correct rollcenter and bump steer for about $250. You could replace every arm and joint on the car and still not hit $2500 though. Unless you only buy Cusco, then it's like LCAs and a sticker for $2500

[MeisterR]

There are alot of factor when you start working out the vehicle dynamics.
Generally rule of thumb is that the lower control arms cannot be lower than when it is parallel to the ground.

If you get pass this point, that is when the roll centre really start getting out of whack and you start seeing performance reduction.
But if you compare it lap time against lap time to a stock suspension, very often aftermarket suspension still fair better due to increase in roll stiffness from higher springs rate and damping rate.

It is never clear cut black and white.
And what works for one may not work for another.
But these rule of thumb are there for a good reason, and generally they give you a pretty accurate result; but not always.

Jerrick