Effects on Performance Widebody / Aggressive Wheel Offset
 

Hi all,

I am considering a couple of different options for my car. One of them being the CS Moonbeam kit. While I definitely hit like on a lot of superlow widebodied cars, that isn't ultimately the direction I am headed. I would love to run a widebody, but I will still be doing autoX and HPDE in it. If I severely compromise my ability to do those things I won't consider. Hence the reason I am posting.

I have spent the last few days reading about the effects of increased offset and these are the current understandings I have:
Cons:
-increased wheel bearing load/wear. getting a set of cryotreated bearings would potentially reduce this concern
-increased scrub radius. some of the negative effects of this should be negated by the fact that our tie rods are connected behind the hub from my understanding.
-Reduced effective spring rate. New springs are easy.
-widened track might make autoX more "interesting"
Pros:
Ability to run wider tires. I find that a very appealing proposition in the FR of the car in particular, as these cars tend to love wide rubber up front. (please lets not turn this in to a bicycle tires are as good as wide tires argument... :roflpuke2:)

My current suspension setup is
Stance SS+ Coilovers True Type with custom 13/9 spring rates
Hotchkis Front Bar
SPL everything

The wheel/tire setup I would run along with this kit:
10.5 (-5ET) FR | 12.5 (-5ET) RR.
295 FR | 345 RR
This setup would effectively move the our rim of the wheels out:
Outside edge 2.8" FR | 3.3" RR
Inside edge 1.3" FR |*.78" RR
Not sure if this is the right numbers to be concerned about or not. I understand how offset effect the wheels relationship to the fender and strut, but not how it effects the centerline of the wheel exactly, at least not for this type of conversation about pivot points and what not.

My question is (putting the wheel bearing issue aside and given the setup I am trying to run) what effects on handling would you guys estimate I would see on the 370? Obviously anyone with real world experience would be best, but I will take the theoretical stuff at this point, as I expect there aren't too many widebody 370z being tracked at this point. Should I be concerned? I am obviously not a pro, so it mostly about having fun, but I don't want to seriously compromise the driving experience, and hopefully might get a little more handling out of the wider front tires.

Thanks!

Extremely stupid question, or uncharted territory?

If it is the previous, lmk, it isn't to late to change my mind.

I haven't seen a widebody 370z on the track yet, but then again, I don't see many of them at all. One issue you may find going that wide up front is that you may start boiling your power steering fluid. You might want to invest in a larger core than the tiny stock one.

I'm interesting in going to wider wheels as well, once my build is done. Probably something like 18x10.5", but I've only just started thinking about it.

good point on the PS cooler.

i guess i may have to blaze the path on this one. first(?) performance oriented widebody Z34 here i come!

Widebody, no. Staggered tires, no. Big front sticky tires, yes.

I run Hoosier A7 315's all around on my autox car. Going square just makes the car so much happier.

Also, fwiw, I have the Z1 PS cooler and still boil my ps fluid at virtually every event. :shakes head:

I was literally just talking to my brother about the idea that running something even bigger rubber up front was very appealing. he is running 285 up front and loves it. glad to hear that even more rubber does even better.

What are your wheel specs?

Setrab has small Cooler cores that have SPAL fan on them, work great for drift/AutoX cars that are not always moving very fast with lots of air flow. May work well for you guys.

What rim size and offset are you using for 315 square?

Volk TE37sl
18x10 +30 front
18x11 +18 rear
315/30-18 on all 4

One thing most people don't think about is rolling resistance, gomer has 315 for autocross, great set up, tons of hard corners, breaking and acceleration from a low speed, for a track car might even be perfect, but there is at a point in tire vs car that too much tire can slow you down, I run 285 square for my autocross car but I'm in a stock class, yeah I'd love more tire and think the car would enjoy it but wouldn't need too much more in my opinion.
Just food for thought