M3 Rear wheel 20"*11" offset ET37 or ET42

[coldfish]

hi,

I am hesitating on rear wheel offset between ET37 and 42. ( not a range, only two options, 37 or 42)

I will run 295/30 R20 Ps4s tire on rear wheel and will lower rear with 12-15mm on MP HAS kit.

just not sure which offser(37 or 42) would the right one to have no rubbing (even with fully loaded) but also make it look good with lowering. Need some help to make the decision. Thx in advance.

updated: decided to go for ET37! Thx for all the help.

best,

[clutchdj]

42MM. You can always run a 5MM spacer to get you back to 37.

[SO17]

37mm. I cant see the point in custom wheels then fitting spacers. I have 20x11 with a 35mm offset on the rear and it's really flush. I also have 295x30 PS4S and if anything, they look a little stretched and I wished I'd fitted 305x30 now.

[coldfish]

Originally Posted by SO17

37mm. I cant see the point in custom wheels then fitting spacers. I have 20x11 with a 35mm offset on the rear and it's really flush. I also have 295x30 PS4S and if anything, they look a little stretched and I wished I'd fitted 305x30 now.

I decided to go 37mm. thx a lot

[clutchdj]

Originally Posted by SO17

37mm. I cant see the point in custom wheels then fitting spacers. I have 20x11 with a 35mm offset on the rear and it's really flush. I also have 295x30 PS4S and if anything, they look a little stretched and I wished I'd fitted 305x30 now.

It’s not really about the wheels. It’s about the tires section width & compounds between different brands. For example cheater tires generally run more square and wider. If the OP runs the same tire over and over then yeah go with the lower ET. 4s are great street tires

[THEROK]

I'd go ideally 40, but 42 with the 295s.

People say often how they don't rub at all, but I'd love to see some rear inner fender liner shots to truly show whether they're rubbing or not rubbing.

[Signature Wheel BMW]

ET37 for 295/30/20 and ET40-42 for 305/25/20.

[coldfish]

Originally Posted by Signature Wheel BMW

ET37 for 295/30/20 and ET40-42 for 305/25/20.

why is this ? should 295/30 have a larger diameter than 305/25 ?

[Circuit Hunter]

Originally Posted by Signature Wheel BMW

ET37 for 295/30/20 and ET40-42 for 305/25/20.

This...

[Signature Wheel BMW]

Originally Posted by coldfish

why is this ? should 295/30 have a larger diameter than 305/25 ?

Less aggressive offset for narrower tires, nothing to do with the tire OD.

[gnhm3]

Originally Posted by SO17

37mm. I cant see the point in custom wheels then fitting spacers. I have 20x11 with a 35mm offset on the rear and it's really flush. I also have 295x30 PS4S and if anything, they look a little stretched and I wished I'd fitted 305x30 now.

Very interesting. What suspension are you running?

[Poiseuille]

I'd have voted +37 as well. So when you get it mounted you should post a picture.

[coldfish]

Originally Posted by Poiseuille

I'd have voted +37 as well. So when you get it mounted you should post a picture.

will do for sure.. thx a lot

[coldfish]

Originally Posted by Signature Wheel BMW

Less aggressive offset for narrower tires, nothing to do with the tire OD.

IMO larger OD makes the tire closer to the fender, making it easier to rub when spring is compressed.

I checked my friends wheels today. He has ET37 20"*11" 295/30 on M4 with lowering 10mm. It feels quite close to the fender. M3 has bigger fender than M4, making the fender closer to tires than M4. I think ET37 with 305/25 might be the way to go. do you have any experience with ET 37 11" width with 295/30 ?

also, please correct me if I said anything wrong. thx in advance.

[Signature Wheel BMW]

Originally Posted by coldfish

IMO larger OD makes the tire closer to the fender, making it easier to rub when spring is compressed.

I checked my friends wheels today. He has ET37 20"*11" 295/30 on M4 with lowering 10mm. It feels quite close to the fender. M3 has bigger fender than M4, making the fender closer to tires than M4. I think ET37 with 305/25 might be the way to go. do you have any experience with ET 37 11" width with 295/30 ?

also, please correct me if I said anything wrong. thx in advance.

Signature Flagship Series in 20x9.5 ET18 and 20x11 ET37 below. MP4S 265/30/20 front and 295/30/20 rear. The owner below tried 305/25/20 rear and rubbed under load. It can be fixed with camber of course. However, the F8x is plague with traction issues. Wider tires and more camber would be counter intuitive for straight line traction.

Also, 265/30 and 295/30 is ideal to keep the tire OD ratio front to rear close to OEM. Keep in mind the stock setup is 2.2% taller in the rear.

We've done over 300 sets for the F8x platform. I think we got the fitment down to the science and openly share our findings on the forum. We do ask about the camber, suspension, and desired look to ensure each set is perfect.

[Circuit Hunter]

^Agree 100%. I've run 275's, 285's, 295's, and 305's in this platform and 305's in the rear is optimal especially with non r-comp. This platform needs the meat.