How to find equivalent offset to replace stock wheel?

[Roberttan]

14 hours ago, Stooky said:

My car stock wheel is 17x7 offset 39. Is it ok to change to aftermarket 17x7 offset 50 rim? Can clear brake caliper

is ok to change to offset 50 but which I usually  do not do that, I always change to smaller offset number to make the wheel more flush to my car fender.

to clear your brake caliper  you better check with the Seller or test it physically. 

[GTO-1]

One thing people always forget when calculating offsets that too much difference to your offset can create a different scrub radius, which can affect car handling. They say even a 5mm difference in scrub radius can change handling characteristics. 

You want to err as much as possible on a zero or negative scrub radius if at all possible, otherwise car could be a bit more wild on handling. 

[Stooky]

9 hours ago, Roberttan said:

is ok to change to offset 50 but which I usually  do not do that, I always change to smaller offset number to make the wheel more flush to my car fender.

to clear your brake caliper  you better check with the Seller or test it physically. 

I am looking at rays forged wheels for Altis. They only have offset 50 for pcd 5x100. Can clear brake caliper but it seems to be hidden in the fenders. Any cons other than appearance?

[Roberttan]

13 hours ago, Stooky said:

I am looking at rays forged wheels for Altis. They only have offset 50 for pcd 5x100. Can clear brake caliper but it seems to be hidden in the fenders. Any cons other than appearance?

your car Share the same PCD with Subaru , thus the available wheels for 5x100 mostly target the Subaru car and Subaru uses higher Offset 45 up.

since you have known this offset 50 make it hidden in the fenders is GOOD, other than appearance is subjective.

as mentioned earlier this offset 50 should able to cleared and need physically test by the installer.

just MHO

[JX83]

Hi I would like some advice on the rim offset. Previously I was on 235/40/18 tyres 18x8j ET37 rims with 20mm spacer and on stock suspension. When going over high humps or even going up steep to low gradient roads, I will bua the rear fender.
Recently I have change my tyres to 225/40/18 and it does improved but occasionally I still bua the rear fender. Reason is the rear stock suspension is too soft/comfort.
Will changing another set of rims to 18x8.5j ET44 helps or changing spacer to 15mm will be easier? Thanks.

Edited November 8, 2019 by JX83

[inlinesix]

43 minutes ago, JX83 said:

Hi I would like some advice on the rim offset. Previously I was on 235/40/18 tyres 18x8j ET37 rims with 20mm spacer and on stock suspension. When going over high humps or even going up steep to low gradient roads, I will bua the rear fender.
Recently I have change my tyres to 225/40/18 and it does improved but occasionally I still bua the rear fender. Reason is the rear stock suspension is too soft/comfort.
Will changing another set of rims to 18x8.5j ET44 helps or changing spacer to 15mm will be easier? Thanks.

Simple.  Change to stiffer spring.

[JX83]

16 minutes ago, Davidtch said:

Simple.  Change to stiffer spring.

Hahaha a friend advise me exactly the same thing and ya i also think this method will work but I told him another problem will occur because by design my original stock exhaust is already quite low and if change stiffer spring my ride height will drop 1 to 1 1/2 fingers then my exhaust will hit some of the kerb when parking. Example like sgh open carpark, I park there my exhaust is like left around 5mm gap only.
Unless I don’t park all the way in if change stiffer spring. 😅🤣

[inlinesix]

5 minutes ago, JX83 said:

Hahaha a friend advise me exactly the same thing and ya i also think this method will work but I told him another problem will occur because by design my original stock exhaust is already quite low and if change stiffer spring my ride height will drop 1 to 1 1/2 fingers then my exhaust will hit some of the kerb when parking. Example like sgh open carpark, I park there my exhaust is like left around 5mm gap only.
Unless I don’t park all the way in if change stiffer spring. 😅🤣

Maintain the same spring length but increase spring stiffness.

For e.g. current spring is 5cm long with 10nm strength.  Change it to 5cm long with 15nm strength.

[JX83]

4 minutes ago, Davidtch said:

Maintain the same spring length but increase spring stiffness.

For e.g. current spring is 5cm long with 10nm strength.  Change it to 5cm long with 15nm strength.

I see.. I get what u mean. 👍 Thanks will try to find a suitable spring.