Camber Question - Front/rear bias Discussion

[ZimmyBRZ]

I just got my BRZ’s alignment done, after finishing all my planned suspension upgrades. (BC racing coilovers, adjustable RCLAs and toe arms, whiteline front/rear end links) I had previously gotten another alignment where they didn’t adjust my rear camber, although i found out that was my fault as i didn’t have the necessary toe arms since my car is lowered.
So I got what I wanted. -1.55 all around, aiming at increasing front end bite and negating stock understeer bias. So far it feels great, rotates predictably and feels nicer mid-corner. (this is a daily)

My question to you guys is, what do you prefer? Is it better to have a front-biased or rear-biased camber setup? I’ve seen people say both, that higher camber in front makes the car handle better, but that higher rear camber is safer and more stable. Thoughts?


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[cmiovino]

Front bias for camber for sure. The wheels are doing the turning, even if you're just talking about a street setup. The rear needs some camber, but not nearly as much. For good overall balance, meaning a neutral handling car, you're going to need more camber up front. With even front to rear camber, it's probably going to understeer at the limit a good bit. Again, a lot has to deal with your other settings, springs rates, swaybars, etc.

For autocross, I run -4 up front and -2.5 rear. If I was doing a street only setup, I'd probably be in the -2.5 front, -1.5 rear area. I ran my WRX back in the day with -2.5 up front and it was mainly a street / daily car. You won't see any negative effects from the camber if you're keeping around zero toe until around -4 degrees or so. Toe is what wears tires, not necessarily camber, until you get more extreme.

You really shouldn't have needed any additional toe arms or anything in the rear. Toe is adjustable from factory all over on the car. I'm lowered on coilovers and didn't install toe arms. The toe arms just give a larger range of adjustability, but most people don't need them.

"Safer" is relative. Even at -4 front, -2.5 rear, my car is still going to understeer if you're cooking it too fast into a corner. With proper tires, the rear end isn't going to be loose at all unless it's wet out and you're almost intentionally trying to do something wrong. If you're at street speeds, you should be fine with less rear camber.

[Ohio Enthusiast]

Originally Posted by cmiovino

Front bias for camber for sure. The wheels are doing the turning, even if you're just talking about a street setup. The rear needs some camber, but not nearly as much.

The main need for extra static camber in the front is due to the strut vs. multilink suspension - the rear gains negative camber on compression (outside wheels during a turn) while the front does not.

One more degree of negative camber in the front is the general recommendation, but it would typically require reducing camber in the rear on a street setup (as the stock suspension is already at -1.5 and any lowering will quickly get you close to -2.5). Most folks with lowering springs and camber bolts (myself included) don't bother with rear camber adjustment and end up with either similar or only slightly more negative camber in the front (I'm running -2.8F/-2.3R).

[Racecomp Engineering]

It's also tire + grip level and spring rate dependent.

- Andrew

[ZDan]

I don't really think it's critical to have more front camber than rear. For handling balance during hard cornering, it *is* important to have a decent amount of front camber, but there are other things that are more important.

On my '17 BRZ PP on lowering springs and stock Sachs dampers I ran -3.2 front camber from camber plates and -2.8 rear camber from lowering, and it understeered. Not enough front suspension travel. Going to Bilsten B8s helped a lot but I'd still get understeer around some corners (T4 running Palmer Motorsports Park clockwise was maddening).

On my '23 with RCE SS-2 coilovers (with non-standard 7F/9R spring rates), initially I was limited to -2 front camber and again at around -2.8 rear from lowering. And that setup's balance was *brilliant*, I was amazed at how well it pointed compared to the old car (despite "worse" F/R camber split). I've since been able to get the front camber up to -3.5, but honestly the handling balance at the track is not hugely different. Tire wear is more even though...

Anyway I see all the time people think they need adjustable rear control arms to reduce rear camber on lowered cars to get "more front camber than rear". Honestly, you don't... On a lowered car with front camber limited to, say, -2, and rear naturally getting -2.8 from lowering, it is not that big a deal and IMO you won't really affect the handling balance much if at all by reducing rear camber to less than the front.

Anyway, -1.15 is pretty modest camber even for a street-only car IMO. You could go -2.0, -2.5, even -3.0 is streetable as long as toe is kept minimal.

Edit/Addendum: Of course street only there's zero need for -3, still street only I'd probably go with something like -2 minimum up front, and whatever results from lowering in back with the stock suspension arms (-2.8 degrees at about 330mm ride height in my experiences).

[whataboutbob]

When I measured the camber curve on the front of my car, it lost 1.5 degrees of negative camber at full compression. The rear will actually gain at least 1 degree of negative camber at full compression.

As others have noted, the "right" amount of camber depends on your setup and use case. Ride height, spring rates, sway bars, toe, caster, tires, driving style, and use case will all influence what is right for you and your car.

That said, right now on 280TW street tires I'm running -3.25F, -2R, and zero toe (F+R). My car feels great to me for my street driving use case.

[smackrel]

Originally Posted by whataboutbob

When I measured the camber curve on the front of my car, it lost 1.5 degrees of negative camber at full compression. The rear will actually gain at least 1 degree of negative camber at full compression.

As others have noted, the "right" amount of camber depends on your setup and use case. Ride height, spring rates, sway bars, toe, caster, tires, driving style, and use case will all influence what is right for you and your car.

That said, right now on 280TW street tires I'm running -3.25F, -2R, and zero toe (F+R). My car feels great to me for my street driving use case.

The bold part is wild to me. Not that I don't believe you, but that just seems krazy. What mods did you have at that time?

[RT-BRZ]

Originally Posted by smackrel

The bold part is wild to me. Not that I don't believe you, but that just seems krazy. What mods did you have at that time?

I agree with you. Given that the suspension travel on these cars is already short from the factory and, if you have done any kind of coilovers worth a damn, it just gets shorter from there. It's hard to imagine that the camber curve is that extreme. Crazy stuff.

[ZDan]

The good news is, these cars and most 200tw tires are not all that sensitive to relatively big changes in camber. The important thing IMO is, for street, geez get yourself at *least* -1.5 front camber. At the track, depending on setup, -2 might work but you probably want at least -3 and I'm running -3.5. For rear camber, don't worry about it and for God's sake don't buy a set of adjustable RLCAs just because you want rear camber to be less than the pathetic front camber you have! Just let it be and run the factory control arms. IMO...

[whataboutbob]

Originally Posted by smackrel

The bold part is wild to me. Not that I don't believe you, but that just seems krazy. What mods did you have at that time?

I should have clarified that that camber loss was for the full stroke of the suspension travel, I had the car up in the air when I measured it.

CASCAMs, RSR Moto-Spec coilovers, SPL FCAs.