[spirit3d88]

Hello everyone !, I currently carry the M442 Bi-color 19 "with measures 225/40/19 8J ET35 in front and 255/35/19 8,5J ET47 in the back.

I want to ride a concave tire, I have looked several and I am currently decided by the Japan Racing JR30 but I want them to be flush with fins without protruding and with a good concavity.

My thought was to keep the original measurements but instead of 8J in front, move to 8.5J and behind 8.5J to 9.5J.

My problem is the following, that ET is the correct one so that the tires are perfect and concave.

I've seen people who have ordered these tires and they stay flat and I do not want that, I want concavity.

THIS DOES NOT!

http://www.picluck.net/media/1954625...995_6120080534

I have seen these photos, so you can see what I want to do.

https://www.flickr.com/photos/jrwhee...n/photostream/

https://www.flickr.com/photos/127660436@N02/30812212608

I would appreciate it very much.

Thank you!

[alohasurftoad]

if you want concavity, the wheel has to be wide and the offset has to be low. if the wheel is wide and the offset is low, it will be sticking out beyond flush unless you add negative camber and use stretched tires. with stretched tires the wheel edge will still be protruding though the tire shoulder may not be.

on this platform(F3x), generally you can only have mild to medium front concavity in front and medium to mildly-deep rear concavity unless you do the things i've said above, depending on the wheel face design.

the JR30 wheel and tire sizes i would use is 19x8.5 +30 front, 19x9.5 +40 rear with 235/40/19, 265/35/19 or 225/40/19, 255/35/19 sized tires. the concave will be flat-mild in front and medium at rear, though.

[spirit3d88]

Originally Posted by alohasurftoad

if you want concavity, the wheel has to be wide and the offset has to be low. if the wheel is wide and the offset is low, it will be sticking out beyond flush unless you add negative camber and use stretched tires. with stretched tires the wheel edge will still be protruding though the tire shoulder may not be.

on this platform(F3x), generally you can only have mild to medium front concavity in front and medium to mildly-deep rear concavity unless you do the things i've said above, depending on the wheel face design.

the JR30 wheel and tire sizes i would use is 19x8.5 +30 front, 19x9.5 +40 rear with 235/40/19, 265/35/19 or 225/40/19, 255/35/19 sized tires. the concave will be flat-mild in front and medium at rear, though.

Sorry for the delay in answering, putting 8.5 and et35 was my idea and 9.5 Et 40 at rear.

I will keep the initial measurements 225/40/19 front and 255/35/19 at rear, I do not care if the tires are stretched a little.

I measured with a level to see the gap that was in the front and back.

And in front I have a gap of 10mm between the fin and the rim in 8, and 20mm in the back with the rim in 8.5

Is it worth going down from et35 to et30? , we are not going to get just concavity and those 5mm may come out of the fin of the vehicle and look ugly for my taste.

I let myself be guided by your advice ��



I know that in this photo they are 20 "wheels and it has cushioning and springs, but I love this design

[alohasurftoad]

i speculate jr30 comes in 3 or 4 levels of face concavity. mild, medium, deep, super deep. they will add or remove material at the hub to set a given offset.

on the 19x8.5, from +35 to +30 the face design will not change. they will leave +5mm more thickness at the hub on the +30

if you want the front to be concave like the 20" photo, you'll have to use 9.5" +35 up front with 255/35/19 tires.

unfortunately the 19" isn't offered in 19x10 for the rear. you could do 19x11 +45 with 295/30/19 and add some negative camber if you want. but i'm not sure if you will rub the inside or fender. another combination with more stretch is 245/35/19, 285/30/19 on the 9.5 and 11, respectively.

otherwise you'll have to use 19x9.5 +35 with 255/35/19 for front and back

hope you can understand what i'm writing

like i said earlier, 19x8.5(mild) +(30-35) with 225/40/19, 19x9.5(medium) +(40-45) with 255/35/19 is the easiest best fitment based on your needs. you'll have to accept the concave that is offered.

[spirit3d88]

Originally Posted by alohasurftoad

i speculate jr30 comes in 3 or 4 levels of face concavity. mild, medium, deep, super deep. they will add or remove material at the hub to set a given offset.

on the 19x8.5, from +35 to +30 the face design will not change. they will leave +5mm more thickness at the hub on the +30

if you want the front to be concave like the 20" photo, you'll have to use 9.5" +35 up front with 255/35/19 tires.

unfortunately the 19" isn't offered in 19x10 for the rear. you could do 19x11 +45 with 295/30/19 and add some negative camber if you want. but i'm not sure if you will rub the inside or fender. another combination with more stretch is 245/35/19, 285/30/19 on the 9.5 and 11, respectively.

otherwise you'll have to use 19x9.5 +35 with 255/35/19 for front and back

hope you can understand what i'm writing

like i said earlier, 19x8.5(mild) +(30-35) with 225/40/19, 19x9.5(medium) +(40-45) with 255/35/19 is the easiest best fitment based on your needs. you'll have to accept the concave that is offered.

Yes, I understand, the translator, although sometimes he gets embarrassed, I get jejjej, my idea is not to change the width of the tire to prevent it from rubbing against the edge.

The et 35 front I was able to see in a f30 vehicle with JR28 tires in 19 "of Japan Racing that is practically flush with fin, but nevertheless in the rear with 19 x 9.5 et35 ... protrude approx 5 mm from the body and it is aesthetically ugly for my taste and I can not pass ITV (Technical Inspection of Vehicles) here in Spain to not be legal measures to excel the body. ET 40 will stay just flush.

I have used these two programs to see if it was right or not and I think they have served me.

My idea is not to put dampers or springs to lower the vehicle, these roads ... are as bad as to put 20 "..

https://www.1010tires.com/Tools/Whee...et-Calculator#

https://llantasneumaticos.com/calc/?...l=70mm&sr=20mm