Wheel Offset Thread

[carrera2RSL]

There have been a lot of questions about offsets and how big you can go, how aggressive you might be with offsets and so on.

I don't want to explain what offsets are, how they change the feel of the suspension and affect handling. In any case I am not an expert, although I do know a little about suspension. This thread is about what people have used and fitted and what the equivalent spacer with stock rims might be for the same effect. BUT the tyre bulge adds more complication, you can definitely fit a more aggressive offset if you run a wider rim.

This is useful and save playing with the calculator http://www.willtheyfit.com/index.php...1-5&offset2=32

Stock 20" rims are 9x20 et 32 F and 10x20 et 34 R
Stock rim measure 277mm R and 253mm F outer rim edge to outer rim edge (just under 1 " more than the bead width)

My 10x20 and 11.5x20 Signature SV104 rims measure 280mm and 318.5mm outer rim edge to outer rim edge
Measuring stock tyres with a flat edge across and seeing how much wider than are than the rim edge I make 265/35 PSS on 9" stock rims 5mm and 295/30 PSS on stock 10" rims 9mm

Anyhow this is just data for you all and has come mostly from people on the forum and posts and all fit with no rub the last digits are the calculation of what the outer rim edge (not tyre) will be if you used a spacer on stock rims. So 13/15 means the outer rim edge with this set up has the same outer rim position as a stock rim with 13mm F and 15mm R

9.5x21 et25 11x21 et31 13/15
9.5x20 et17 10.5x20 et25 (blk BBSf1) 19/15
9.5x21 et28 11x21 et30 10/16
9.5x21 et25 11x21 HRE et31 HRE P101 13/15
9.0x20 et18 11x20 et 31 klassen black 14/15
9.5x21 et23 11x21 et25 pink rotoform 15/21
9.5x19 et22 10.5x19 e22 Orange Ray's 16/18 not M5 ?
10x20 recommended et30 front 14
9.5x21 et21 10.5x21 et25 17/15 no rub
10x20 et40 11x20 et30 Zito 14 or 15/16
10x 21 et 26 11x21 ET 26 19/21 grey M5
9.5x21 et20 11x21 et25 6sixty 18/21
9.5x20 et25 20x11 et32 265/305 13/14
10x20 et27 11x20 et27 265/295 18/20
20x10 et25 11.5x20 et30 20/23 BC forged
20x9.5 et25 11x20 et28 275/305 forgeline 13/14
21x10 et26 21x11 et26 Velos grey 19/21
9.5x20 et28 10.5x20 et 25 275/305 10/15
20x20 et25 11.5x20 et35 265/305 SV quoted specs 20/18
21x10 et25 21x12 et40 275/325 SV quoted specs 20/19.5
20x10 et28 20x11.5 et33 SV 104 275/35 305/30 17/20

For those with KW V3 suspension when running 15mm spacers on stock wheels and tyres I know I have 47mm clearance shock to rim edge inside and 38mm from the tyre at its widest point (295's are wider than 10" rims). Interseting that the SV quoted offsets for a 12" rear wheel is 46mm closer to the strut than my set up, clearly this would be too tight (I think with 20") but the clearance increases as you go higher up the strut, so more room with 21's inside than 20. More information, I thought moving from et 19 (15mm spacer) with 10" rims to et33 with 11.5" rims would close the 47mm clearance down to 14mm at the rim edge. But I now measure 12mm, this is because of measurement accuracy and the fact that my rim are a little wider rim edge to rim edge. Allowing for the 3mm extra width or so, I'm spot on. So.... using an et33 11.5" rim will leave 12mm-14mm depending on rim manufacturer on the inside and easily fit 305/30. Possibly 325/30. 275/305 on with room. I think I could have gone et30 with 305/30 at the back.


As for the secretive offset police and manufacturers that won't publish offsets, like it's a black art. Why not be helpful ?

I like to see how a wheel looks for stance as well and just 'fitting' is not helpful at all. I hope this is helpful

Here is a picture of the inner clearance at the back with 305/30 20, 10mm of clearance including tyre bulge, this is 11.5 et 33. I think 10x12 et 35-36 would be as tight as you would want to go with 20's with any tyre bulge (325/30 ?). This would easily clear on the outside. only 3.3mm more poke which be fine. I will put on some 3mm spacers and see if it clears. I THINK a 12x20 et 36 would work with 325/30 as the 325/30 measures 13" on an 11.5 rim, a 12 will be 13" wide rim edge to rim edge. 12x20 with 305/30 20 et 36 would clear on my car...

UPDATED 26.10.17

[josec70]

Really good compilation of information.

[m5 guy]

Awesome info. You can push offsets plenty on this platform, though not as crazy as the e60. Looking at my particular setup (the velos) I could easily do a 21 x 10 et 20 instead of my current et 26 as long as I stay with a 265. My camber is almost -2 in the front so that's another factor.

In fact for my next setup I'm considering 21 x 10 et 20 and 21 x 11.5 et 30 with the usual 265/305 super sports. The baby stretch should be the same this way and the lips should be wide.

Great post op!

[josec70]

Originally Posted by m5 guy

Awesome info. You can push offsets plenty on this platform, though not as crazy as the e60. Looking at my particular setup (the velos) I could easily do a 21 x 10 et 20 instead of my current et 26 as long as I stay with a 265. My camber is almost -2 in the front so that's another factor.

In fact for my next setup I'm considering 21 x 10 et 20 and 21 x 11.5 et 30 with the usual 265/305 super sports. The baby stretch should be the same this way and the lips should be wide.

Great post op!

First dibs if you sell the current Velos setup.

[m5 guy]

Originally Posted by josec70

First dibs if you sell the current Velos setup.

If you are serious about it I can definitely sell them. Just give me a pm!

[carrera2RSL]

I did try and calculate how much the increase in camber might move the front and rear wheels at the top by the arch lip. A little pointless at the front, as no adjustability ! But if my maths are correct 1 degree of negative camber at the rear will move the upper part of the wheel in by 5-6mm, so 1/2 degree of additional negative camber at the back might be 2-3mm of extra clearance on the outside with a reduction on the inside ?

[carrera2RSL]

Updated with Signature wheel offsets for the M5, with 11.5 and 12" quoted

[carrera2RSL]

Updated with measurements from Signature SV104 10x20, 11.5x20 and stock rim measurements

[MpowerMike]

21x10 +17 & 21x12 +35 , will this setup fit ?

[rlsl]

Since I am considering parting my wheels out. Maybe I will share the offset here...i am far more "aggressive" than any of the setup on that list
21x10.5f 21x12r stretching 275/295

[carrera2RSL]

Hmm, please do share :-)

I think 12.5's might be et 30-35 ?!

[MpowerMike]

Originally Posted by rlsl

Since I am considering parting my wheels out. Maybe I will share the offset here...i am far more "aggressive" than any of the setup on that list
21x10.5f 21x12r stretching 275/295

CAN you please share the offsets , I’m wanting to go for a 12@ wheel in the rear.

[carrera2RSL]

Mike,

The best way to be sure is to measure your inside clearance. My match was spot on and if your running KW V3's (not sure how they differ) I know now I could fit 12's with 20 R if I ran a 295 or possibly 305 with your proposed offset et 35, seems you can run as inset as et 40.

Have a play with this http://www.willtheyfit.com/index.php...=12&offset2=37

I had zero issues running 15mm spacers lowered with stock 20's. My 11.5 et33, have loads more clearance than before with stretched 295's. Your offset choice will be down to where you want the rim and what tyre you want to fit. If I was staying with 295's I would want more offset than et33 on my 11.5's

SO I think you could run somewhere between 35-40, perhaps less than 35 depending on tyres used. I think even something like et32 might work http://www.willtheyfit.com/index.php...1-5&offset2=33 when you compare to mt 11.5 et 33

By the way 11.5 rims that actually measure (318.5mm) 12.6 rim edge to rim edge (normal but slightly wider a few than some 11.5's) I have 12mm clearance to the KW V3 struts from rim edge, the same as the tyre with 295's as the rim protector doesn't protrude now..

Another calculation you can do which is useful is to see how much the tyre has moved by the centre line and how much it has grown at the tread edge (tree size plus stretch) I have read than adding 1/2 inch to the rim size will stretch something like 1-2mm across the tyre near tread level. So I did my maths here as well and moving from an effective et19 to et33 my true has moved inwards by 14mm but I have added 1.5 inches so it will have grown by a few mm near tread level. I measured the mark where the tread starts on the tyre at the moment with 295's on 11.5 et 33 it is 15mm, it was 1-2mm before, so makes sense. at the rim edge my old 10's with 295's measure 9mm less than the tyre bulge measured with a straight edge. They are now flush, so my rim edge has move out by 5mm (in by 14 and out by 19 width increase) BUT the tyre bulge has shrunk by 9mm !

Now the car is fitted with 305/30, 275/35 and the tyre bulges by 3mm at the back and 2mm at the front, last picture

[carrera2RSL]

Oh I am running 1.5 degrees neg camber at the rear but might increase to 1.8 or so. My maths suggests every degree of camber will move the top of the wheel in by 5-6mm. So I can possibly gain 2mm if needed at the wheel arch (losing 2mm of my 12mm on the inside, I think my inside clearance will reduce by 6mm with 325/30, so I will have 4mm clearance on the inside...)

[ULOOKD]

Ok so I’m looking for a set of wheels for my m5 I want to go something deep, so I found a set of work wheels which i’ll have to redrill. My question is after redrilling to 5x120 would these offsets work?
The specs are:
20 x 9.5 -25
20 x 11.5 -51

Thanks

[carrera2RSL]

More reading required I think ! 20x11.5 et51 will hit your strut....

[ULOOKD]

Here’s the link for the wheels there are a negative offset.
https://rover.ebay.com/rover/0/0/0?m...2F262869681537

[fullhouse customs]

Originally Posted by ULOOKD

Here’s the link for the wheels there are a negative offset.
https://rover.ebay.com/rover/0/0/0?m...2F262869681537

ERRRR, no chance what so ever, but lovely wheels

[HXS]

Originally Posted by ULOOKD

Ok so I’m looking for a set of wheels for my m5 I want to go something deep, so I found a set of work wheels which i’ll have to redrill. My question is after redrilling to 5x120 would these offsets work?
The specs are:
20 x 9.5 -25
20 x 11.5 -51

Thanks

You will poke like a mutha fucka! Are you going for the Mexi-flush look?

[HXS]

Originally Posted by carrera2RSL

More reading required I think ! 20x11.5 et51 will hit your strut....

That’s a negative 51 offset so it will most definitely clear the strut

[carrera2RSL]

Originally Posted by HXS

That’s a negative 51 offset so it will most definitely clear the strut

That's another 3.5" of poke get some arch extensions and viola

[ULOOKD]

Lol nah the mexiflush thing is no no!! Damn they were nice wheels!!!