I’ve been searching the forums, and reading up on tire sizes and wheel spacers. My conclusions are from the comments of others. It seems like the general agreement is to avoid wheel spacers if at all possible. With OEM 19’s, the wheel spacers will push the wheels further apart, reducing the handling performance and creating more oversteer. Is that correct? So the only reason to get wheel spacers with OEM wheels…is purely for looks.

So my question is this. Does handling / oversteer truly become worse as the wheel spacers increase in size since the larger spacers push apart the wheels more? Would getting a larger tire size help reduce this negative effect?

I originally planned on getting 25mm spacers all around, but after speaking to another member here, I think I will get the 15mm all around with 245/35/19 (fronts) and 255/40/19 (rears). Would this be the optimal setup? I thought about getting 20mm & 255/40/19 for the rears, but I heard that it might be too aggressive and the tires might stick out of the fenders. Any suggestions? My main goal is to have my wheels as flush with the fenders as possible while sacrificing minimal loss in handling, and I have a 05 Coupe.

I'm also wondering why people recommend the 245/35/19 over the 245/40/19 when the OEM is 225/40/19. If the OEM tread depth is 40...wouldn't it be best to continue that depth?

Thanks!

 

OKay, NM about the last question I asked...regarding why people recommend the 245/35/19 over the 245/40/19. I understand now. Its because the 245/35/19 is more closer to the stock tire specifications than the 245/40/19 right?

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
225/40-19 3.5in 13.0in 26.1in 82.0in 773 0.0%
245/35-19 3.4in 12.9in 25.8in 80.9in 783 -1.3%
245/40-19 3.9in 13.4in 26.7in 83.9in 755 2.4%

Still wondering about the other questions though...

 

The 40 series puts you off in the front, yes. It fills some wheel gap, but you lose the smooth lower profile look up front.

 

yah, i think ill stick with the 35. ne advice on the other questions...?

 

Does handling / oversteer truly become worse as the wheel spacers increase in size since the larger spacers push apart the wheels more? Would getting a larger tire size help reduce this negative effect?

Heres my take, i think by widening the stance of the car you will actually grab more because there will be more force on the tire on the outside. I have 275/245/35/19 on my 19" and i LOVE the way they handle, ive been through auto x and to the drag strip... love the wider look as well.

 

do you have spacers on as well...or just the wider tires? I can understand how wider tires will improve handling somewhat since there will be more rubber gripping the ground. But I didn't know that the wider stance created by the spacers would improve handling. I always thought it would make the handling worse.


More thoughts...suggestions please!

 

any more thoughts?

 

spacers will somewhat hurt handling because it increases the scrub radius, but no more than low offset wheels. The "proper" way to widen the stance would be to move the whole suspension out so the pivot points would remain the same with just a wider space in the middle. Of course this isn't really feasible, and the difference is minimal and more of a factor during low speed turns, so its not something you should really worry about

 

Thanks for the info redlude. Hearing this from you gives me a more confident feeling.

Do you think the 15mm spacer (all around), 245/35/10 (fronts) / 255/40/19 (rears) combo should work fine?

 

20mm all around with 255/35 and 235/35

 

dude redlude .. is their anything you dont know ? every thread i read you have a knowledgeable answer ...

i bet you dont know how hot a left front rotor would be on a 06 coupe with brembo brakes .. making a right hand turn with a radius of 46 degrees .. with ambient temp at 87 degrees, track temp at 105 degrees =0

 

come on david, you have to challenge him. everyone knows the answer to your question is 174F / 352 Kelvin assuming a slight incline during the turn and static coefficient of friction - duh!

 

i hope you ment 19...

That sounds good but go 20mm spacer in the rear

 

haha you caught my typo!

ah, too late...i already ordered the 15mm spacers.

i was talking to another member on the board, and he said that he had 20mm spacers in the rear with the OEM tire size for the 19", dropped on 350z H-techs. He said it was fine and rubbing wasn't an issue when people were sitting in the back. But he said that if you increased the size to 25mm, and had people sitting in the back, there would be a good chance it might rub. I opted to not take that risk, so ordered the 15mm spacers with the intent to increase the rear tire size to 255/40/19.

hopefully it looks flush.

 

That will help...