Thanks, I'm guessing I may have to roll my rear fenders too. You guys think it might have to happen?

 

Here's what I came up with

FRONT:
19x10 w/275x30x19, 20 mm spacer
-0.235" ride hight over stock
+0.133" on the inside lip of wheel (closer to suspension)
+1.866" on the outside lip of wheel

REAR
19x10.5 w/305x30x19, 25 mm spacer
-0.250" ride hight over stock
+0.187" on the inside lip of wheel (closer to suspension)
+2.062" on the outside lip of wheel


Tire widths are as close to possible to stock ratio (225/245 in my case)

So will the inside clearance be alright with stock/and/or/aftermarket suspension?

How hard to roll the fenders? Front and rear?

 

By the way I'm coming from '04 OEM 18's with sport tire package. According to my research there is a 5mm difference in offset from the 19's which may explain things if my calculations are indeed correct.

 

I'm pretty sure this isn't right. I'll calculate the numbers when I get home

 

OK thanks, there is likely some error in my math. keep in mind my stocks are 18x8 all around with 225/45 front and 245/45 rear. I am moving to 19x9.5 - 19x10 in front and 19x10.5 rear.

 

a 19x8+30 with a 20mm spacer will be equal to a 19x10+35(30mm less inner clearance than stock) or a 19x9.5+29(18mm less inner clearance than stock). With a 15mm spacer, it will be equal to a 19x10+40(35mm less clearance than stock) or a 19x9.5+34(23mm less inner clearance than stock). I recommend either a 25 or 30mm spacer in the front if widen them to 9.5, this will give you a 19x9.5+24 or +19, only a 30mm spacer will work in the front with a 10" width, giving you a 19x10+25.

For the rear, a 20mm spacer will give you a 19x10.5+38(50mm less inner clearance), a 25mm spacer will give you a 19x10.5+33(45mm less inner clearance), and 30mm spacer will give you a 19x10.5+28

 

This is great info guys. I"ll be sure to use this when planning out my wheel widening project. To keep it simple, I can probably use those scenarios listed by redlude for the front and back widened rims.

Then, depending on how they sit, I will get the correct spacer to make them fit appropriately. In addition, I will get my fenders rolled as necessary.

On a side note, do you guys know where I can get a good primer on all of this wheel calculation stuff? So I can make this move with a bit more confidence after some research done on my car?

 

I already have 15/20mm spacers on mine and was thinking about just widening my rears to 10.5 leaving the fronts the way they are...

 

i just wanted to recap a little, i have a set of OE19s with 20/25 spacers and dropped on z Stechs, thinking about moving the rears up front and widening the fronts 2 inches to 10". My fenders were cut already so im now wondering if i should go 10.5"? What do you recommend for a 10" tire vs the 10.5 on a coupe

 

eh kinda bringing back and old thread...

but to the op did you ever do this?

also for anyone knowledgeable in the calculations, what would the widest i could get with 25mm spacers front and rear and still having my rims flush as they are now with 25mm spacers? i understand there probably will be some fender rolling but i dont know also how far i can go with rolling.

 

If you roll the rear finders, you can get 305's on the back, but you need a fairly conservative offset. I went with a 30 offset, but I rubbed on the left side once while at Sebring. A 35 offset might cure that. Nonetheless, I have never rubbed on the street.

 

10" should fit, but 10.5" might stick out a little far if you provide enough clearence on the inside to prevent rubbing against the coilovers (some people like that look, though).

 

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1. They will only widen your wheels 2" so if you plan on widening the fronts, they you can only go up to 10".

2. the widening only extends the wheel in towards the suspension. Thus, it doesn't matter what you do, if you keep the same spacers, the wheels will look the same

 

They will do up to 3 inches on the Rays 19's.