Wheel offset, bore and TPMS

[Lone Survivor]

I've been looking at getting a new set of wheels. I then have to get smashed because I can't take in the plethora of info required for a correct decision.

What I want to know is the definitive answer to the offset value, that will negate the use of spacers for the filled in wheel arch look, no poke, just right.

Bore, what exactly is the hub bore dia?

TPMS, Will my stock TPMS be transferable and under what circumstances would I have to change them?

I would like to keep the wheels 19", but 20" with the correct tyre size to minimise rolling radius difference, but happy for suggestions on this as well.

I've been modding cars for years, and despite having an engineering background, I still can't get my tiny mind round offsets :headbonk:

Plain terms please guys, no gobbledygook, and no Manders posts re painting things :lol: I could just pm Gibbo I suppose, but he'll just write a million word reply that'll cause me to ask another gazillion questions (Gibbo, I welcome your replies )

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[Nookie]

Without meaning to piss you off at the outset... there could be a hundred answers to your questions, which would leave you right where you are now, i.e. confused.

Firstly, the offset will be relative to the rim width ('J') of the wheels, and the rim width will be relative to the size (width) of tyre... so perhaps it's best to try this step by step, so...

1). What sort of set up do you want... square (all four wheels/tyres the same width) or staggered (wider rears)?

2). What sort of tyre width do you want... stock or wider?

3). What sort of rim width do you want... stock or wider (concave)?

 

[Lone Survivor]

Thanks Nookie

1. Staggered

2. Wider, not massively, 285 at the rear, 255 minimum at the front, more if necessary.

3. Wider rim, concave.

Edit: would 19x10 35mm front, 19x11 50mm give me what I want?

 

[Nookie]

OK... that's good.

First, based on the standard rim width/offset, you want to move the wheels outward by approx. 20-25 mm at the front and 20mm at the rear to start getting something like a flush fit.

If as you ask, would 19x10 ET35 front and 19x11 ET50 rear (looks like you're considering Project 6GR's) give you what you want...

Standard front is 19x9 ET45, so an of ET35 means you're moving the wheel 10mm further out, and a rim width of 19x10 is 1" (25.4mm) wider, half of which (12.7mm) is inward and half of which (12.7mm) is outward, so...

You're moving the front wheel outward by a total of 10mm by way of the change in ET, and 12.7mm by way of the rim width = total 22.7mm

Standard rear is 19x9.5 ET52.5, so an of ET50 means you're moving the wheel 2.5mm further out, and a rim width of 19x11 is 1.5" (38.1mm) wider, half of which (19.05mm) is inward and half of which (19.05mm) is outward, so...

You're moving the rear wheel outward by a total of 2.5mm by way of the change in ET, and 19.05mm by way of the rim width = total 21.55mm

I'm not going to confuse matters by explaining the difference in the position of the inner edges of the rims (although you may if I've explained things clearly enough above, be able to suss that out yourself)... but suffice to say there's absolutely no problem with reference to clearance of the suspension components etc.

Ideal tyre sizes for the above would be 275 front and 295 rear, but depending on the profile you go for, there will be a very minor change of wheel diameters as follows (not going to go into calculations at this time for simplicity).

Standard front tyres are 255/40 R19 with a rolling radius of 2070.74mm so...

275/35 R19 will have a rolling radius of 2036.05mm (-34.69mm or -1.68%) which will mean when your speedo reads 70mph you're actually travelling 68.82mph

275/40 R19 will have a rolling radius of 2118.99mm (+48.25mm or +2.33%) which will mean when your speedo reads 70mph you're actually travelling 71.63mph

Standard rear tyres are 275/40 R19 with a rolling radius of 2118.99mm so...

295/35 R19 will have a rolling radius of 2078.27mm (-40.72mm or -1.92%) which will mean when your speedo reads 70mph you're actually travelling 68.66mph

295/40 R19 will have a rolling radius of 2167.24mm (+48.25mm or +2.28%) which will mean when your speedo reads 70mph you're actually travelling 71.60mph

Note: The speedo figures given above for the front wheels are only there for comparative purposes, and the figures for the rear wheels are the important ones as the actual speedo readings are normally taken from the final drive to the rear wheels. Also remember that any change to the wheels will affect the 'true' recorded mileage on the vehicle.

The apparent rule of thumb is that you should aim to stay within 3% of your original size, so a 35 or 40 profile size is acceptable, and it's just down to you and how much rubber you want between the rim and the road... 35 profile will be slightly smaller overall so will (negligibly) increase the gaps between the wheels and arches and give a slightly harsher ride, 40 profile will be slightly larger overall so will (again negligibly) decrease the gaps between the wheels and arches and maintain a similar ride to the standard wheels.

If you want to stick almost true to your current wheel radiuses, go for 265/40 R19 front and 285/40 R19 rear... but keep clear of the kerbs as those tyre sizes will give the minimum of protection to the rim.

It's 4:30am and my brain hurts so I'm going to bed now (we'll talk TPMS and centre bore tomorrow) :eyebulge: !

 

[stevec]

Hi [MENTION=16323]Lone Survivor[/MENTION]

Take a look at my thread at the last few pages. There is a good pic of my new wheels and how they sit.

http://www.mustang6g.com/forums/showthread.php?t=37374&highlight=competition+orange&page=52

These are 8.5 off set front and 10 at rear. They are 20" and I did away with the spacers.

Bore is 70.5 I believe (according to GT101)although I have also heard it is 70.3 (Enoch), both reliable sources so you may want to confirm this.

You will also see on the thread the initial issues I had due to the bore of the new wheels being a different. You can (and I have) sorted this by making sure the nuts are done up correctly and centering the wheel but I am buying rings anyway to deal with this.

Something to also bear in mind is I had to get new wheel nuts as the Ford ones were too big to fit in the holes off the new wheels.

 

[Lone Survivor]

[MENTION=23824]Nookie[/MENTION], :hail:, wow mate, that's just about everything I need to know, you are a star You're right, I'm looking at the project6GR wheels, but also some uk ones, that I can get a custom offset.

The other thing is I'm considering (when funds are available after forking out for wheels and tyres :eyebulge is the rear Brembo conversion and I know the 6GR wheels fit over these.

[MENTION=8211]stevec[/MENTION], thanks Steve, I've been watching your thread since day one mate , I'll have another, more detailed look at it. The rub is, I'm wanting to stay 19", with my suspension set up, I feel I've got that just perfect re drop, but I've not ruled out 20" wheels totally.

I know it's only a pm/message away, but do we know, is there any change to the TPMS set up, i.e., I believe Nookie, you had to get 'stubby' sensors? (Hope you had a good sleep Nookie :lol

 

[Gloucesternige]

Here you go my friend.. http://www.1010tires.com/Tools/Wheel-Offset-Calculator

Just put your existing details in and then the wheels you want to see where they will lie in your arches.

Hope this helps

 

[Enoch]

Thanks Nookie

1. Staggered

2. Wider, not massively, 285 at the rear, 255 minimum at the front, more if necessary.

3. Wider rim, concave.

Edit: would 19x10 35mm front, 19x11 50mm give me what I want?

Those are the offsets I'm running.... this allows a 295/35r and 275/35f

This set up = no rubbing, no poke, rolling radius within a couple of % of standard so no speedo issues, and readily available sizes of tyres from different brands..





Gives a nice fat look from behind.....




If you check out the wheel forum on the US side, you'll see they're now also doing these in a 5 spoke

 

[stevec]

[MENTION=23824]Nookie[/MENTION], :hail:, wow mate, that's just about everything I need to know, you are a star You're right, I'm looking at the project6GR wheels, but also some uk ones, that I can get a custom offset.

The other thing is I'm considering (when funds are available after forking out for wheels and tyres :eyebulge is the rear Brembo conversion and I know the 6GR wheels fit over these.

[MENTION=8211]stevec[/MENTION], thanks Steve, I've been watching your thread since day one mate , I'll have another, more detailed look at it. The rub is, I'm wanting to stay 19", with my suspension set up, I feel I've got that just perfect re drop, but I've not ruled out 20" wheels totally.

I know it's only a pm/message away, but do we know, is there any change to the TPMS set up, i.e., I believe Nookie, you had to get 'stubby' sensors?

No worries.

Trust me, going 20s is one of the best things I have done. I just got lower profile tryes so over all diameter is pretty much the same, so no change to set up. 4 new tyres does hurt the wallet though!

Forgot to mention the tyre sensors. Yeh, at the moment I dont have any but new ones are on there way.

 

[Langburger]

anyone running a 20X10 squared set up with 285/35/20s ?
i like the sound of the new 285 michelin pilot 4s all round

 

[Enoch]

anyone running a 20X10 squared set up with 285/35/20s ?
i like the sound of the new 285 michelin pilot 4s all round

Loads of folk in the US run this set up... don't know any UK owners though:shrug:

 

[Langburger]

love your staggered set up on the project6gr but there doesnt look to be any decent sizes in european supplied michelins or conti 6 in the future
pretty hacked off we dont get a 305 35 19 over here but the squares set up look promising

 

[Nookie]

is there any change to the TPMS set up, i.e., I believe Nookie, you had to get 'stubby' sensors?

You've obviously seen the thread on the wheels I've just fitted ( http://www.mustang6g.com/forums/showthread.php?t=71020&page=4 ) as you're aware of the minor issue I had with the TPMS, however, this was limited only to the front valve stems rather than the stem and sensor, and while it seemed like a PITA when it first came to light (which as I mentioned I'd half expected to be the case) it was in fact a really simple issue to overcome once I'd located the 'stubby' valve stems.

I just bought 4 new genuine Ford F2036804 TPMS sensor kits, which include the sensors and standard valve stems and cost something like £82 (probably just under £95 in the UK with VAT) and swapped over the front stems for the 'stubbies' and all was good in my world!

My heart was originally dead set on the Project6GR wheels from the moment I first saw them on the US part of the forum, but three niggling issues caused me to start searching for alternatives, the first being that they had to be sourced and shipped from the US involving (currently) poor exchange rates, high shipping costs, import duties and taxes (and any other Government department wanting their piece of the action and trying to make it as difficult as possible), the second being the risk of damage while in transit as some of the pics people have proudly posted on here of the newly arrived boxes containing their wheels have looked like they were shipped via Afghanistan, although all so far appear to have been OK, and (linked) thirdly that if ever I damaged one of the wheels (beyond reasonable repair), I'd have to go through all this procedure all over again to get a replacement... hence after reading a thread [MENTION=24982]anubis[/MENTION] posted on the UK sourced (and seemingly widely available) Judd range of wheels, I found that they did the T204's which look almost identical (to my eyes) to the Project6GR/GT350R wheels.

Again the 6GR's were my favourite as they were available in 19", whereas the wheels I've now got fitted are only available in 20"... but do I have any regrets... no way as they look f**king awesome and I'm now really glad I went bigger - but this is just personal choice and there's a valid argument for both sizes (just don't ever do the 22" with 25 profile rubber band tyres thing as it looks bloody ridiculous on a Mustang)!

Regarding the centre bore, as [MENTION=8211]stevec[/MENTION] mentions, this seems to vary all over the place, with 70.3 and 70.5 being the most oft quoted, but the company that supplied me with my wheels dealt with all that as part of their service (fitting a machined plastic ring to the centre bore which fitted on the stang perfectly). If of course you go for the Project6GR, they're custom made specifically for the Mustang so the bore is already machined perfectly hub centrically from the factory.

Good excuse to get another pic of my car/wheels on here !

 

[Lone Survivor]

Thanks again Nookie A lot of good, extremely valuable information there, all in one place

The main reason for the 6GR wheel is it's known to fit over the Brembo rear kit. Stuff to ponder, but I'll be looking to action soon, although my Mrs has just booked a villa in the South of France :doh:

Great looking car you've got there ;)

 

[Nookie]

[MENTION=16323]Lone Survivor[/MENTION] - have you got a link for the rear Brembo kit as not seen this and quite intrigued?

One of the things with now having such open wheels is that they really show off the calipers and discs... and the standard non-Brembo ones on the rear do look a little puny and like they need something doing to them to make them look more important!

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