ET phone home

[quattro]

I am trying to work out the ET (Offset) for my Vitesse wheels and have measured the distance from the outer rim to the mating face at 56mm and the inner rim to mating face at 136mm. So 136 + 56 = 192/2 = 96 less the 56 = 40

So the ET is 40.

The Miniltes work out at 123 and 65 - ET = 29 :shock:

and the spare wheel which is a standard P6 wheel is 116 and 34 which gives an ET of 41.

So why am I of the mind that the offset is 53mm for the standfard P6 wheel?

Did someone tell me that? Have I measured wrong? Is my spare wheel off something else?

Help! :?

 

[quattro]

Well I have fitted the Vitesse wheels and lo and behold the outside of the wheel is quite close to the rear wing, BUT seems to be exactly the same place as the Minilite.

As the tyres are 20mm wider, I can only presume that the Vitesse wheel's offset is indeed 40 and has moved inwards 11mm. (Minilite ET is 29)


With the diameter of the tyre 647mm against the 185 on the Minilties of 650mm, that won't make any difference.

Only one problem which I almost didn't notice/remember.

The rim of the bearing cap actually holds the front wheel slightly off of the hub. Only about 0.5 to 1mm but a gap all the same.

The standard steel wheel has a bigger centre hole and the whole bearing cap including the rim, fits inside of it. The Minilites have an angled centre bore which allows the cap to fit underneath it.

The Vitesse wheels do have a countersink which fits the external diameter of the rim, but as the rim already sits on a slightly risen platform on the hub face it is not deep enough and the wheel sits on the bearing cap rim only, and not the hub face.

I will be sawing the rim off tomorrow Unless anyone knows a better way? I am always open to suggestions

I have also been playing around with some studs and nuts, more of that later though, when I have sorted it properly.

 

[chrisyork]

Hi Quattro

Before you get too enthusiastic sawing bits off, this subject has been done to death somewhat - try doing a search on my posts. To get an ideal solution with the Vitesse wheels you need to skim around 3 to 4 mm (lack of precision because you are likely to find that BL's quality control was also imprecise and the ET will vary wheel to wheel!) off the hub mating surface on the back of the wheel. While this is being done its then easy to machine a larger rebate for the front hub grease cap. This sounds dramatic but is actually very cheap, if the wheels need a refurb or you fancy having the rims polished that can be done at the same time.

With this mod done you should be able to wear 205/65's, which from what you say on diameters is likely what you have. Don't forget that the rear track on a P6 changes according to the bump deflection/ride height. This is because the hubs are actually moving in an arc on the ends of the driveshafts rather than straight up and down. The sliding joint in the de dion is there to accomodate that. So full compression (lots of people, well laid over in a corner etc) brings the wheel further out towards the wheel arch. So don't take the static clearance between the tyre and wheelarch at face value, you actually need a little bit more than that!

They do look good on the car though, don't they!

Chris

 

[quattro]

Interesting stuff

However, I have measured the Vitesse wheels about ten times now and the distance from the inside rim to the mating face of the hub is definately 136mm, not 148mm as in your posts :?

I would therefore need to take 13mm off the wheel centre to get 149mm and 43mm (ET 53) :shock:

The tyres are still on so it could be a little different, but I am not that far out.

I do remember the first time I did this back in the 70s when I did cut the rim off the bearing cap only to find that it would tap on a little further (still had clearance) and allowed me the fit the centre caps

I will have a deeper look through your posts when I get home - must do some work now.

Whatever I do, the steering and general geometry will be much better than the Minilites at 29!

Oh and yes, I do like the look of them

Any ideas what the Minilites were designed to fit?

 

[DaveHerns]

I went out for a 2 hour lunch today and missed a set of those wheels on EBay for not a lot of money
Then my 3500s might have looked as good as Quattro's (same colour)

 

[quattro]

I went out for a 2 hour lunch today and missed a set of those wheels on EBay for not a lot of money
Then my 3500s might have looked as good as Quattro's (same colour)

Do you want some minilites? 8)

 

[chrisyork]

The other significant volume car of the period with the same stud pattern was the Westminster / Wolsely 110. Some of those were competed in their day, not least due to the engine interchangeability with the big Healy. Perhaps they were intended for those? Actually I wonder what wheels steel wheeled big Healy's wore - that could have been more likely.

As to ET measurement - I don't have an opportunity to repeat them at the moment as all my wheels have tyres on. But just in case of misunderstanding, my measurements were from the extreme outer edges of the rims, done by laying a straight edge to span the inner rim and measuring down to the hub mating face. I didn't measure the equivalent from the outer rim to the mating face, just the overall width across the extremes of the rims.

What is beyond doubt is that the 3 to 4 mm we skimmed made all the difference. From a marginal clearance I am now able to comfortably get knuckles into the gap without it fouling at the rear.

As an aside, I started by trying to use Jensen Interceptor 3 wheels, which is how I discovered the significance of ET! The Vitesse wheels are astonishingly heavy compared to the Jensens (made by GKN), so use of the Vitesse wheels definitely doesn't do much for unsprung weight!

Chris

Chris

 

[quattro]

I cut a piece of strong timber to sit on the outside of the rim without touching the tyre.

Then measured from the timber to the mating face of the hub.

Then using the same piece of wood, did it the other way.



I have now found that the spare wheel in my car is a steel wheel but is not the correct P6B one. It is a 5J, not a 5 1/2J. Possibly from a 4 cylinder car, or something completely different. It does have a brand new 184 R 14 90H tyre on it though 8)

I am starting to wonder if there is anything right on this car? :?

The Vitesse wheel states on it - CRC4177 6.5J x 15 x 40 - and it is an ET of 40.

I can see that skimming the 3mm will be a benefit though - anyone know where I can get it done and what sort of cost it is?

 

[chrisyork]

Spot on, that's exactly how I did it. Wheel maching places are surprisingly common. Here's one I identified from the web: http://www.alloywheelrepairs.net/index.html . But I've actually used places identified through tyre retailers for mine. You need the better class of operation, the sort likely to have full (not just tracking) laser wheel alignment equipment, of the type you might use to set up the adjustable back suspension of a Subaru, say. I've used Protyre in Bristol and MIcheldever Tyres (in Micheldever :? ) but there are likely to be a few reasonably local to you.

Chris

 

[richarduk]

I have now found that the spare wheel in my car is a steel wheel but is not the correct P6B one. It is a 5J, not a 5 1/2J. Possibly from a 4 cylinder car, or something completely different.

You're not alone, when I took my old girl into her first MOT the guy pointed out that the rear tyres were different sizes! I thought it looked odd, had assumed it was a saggy spring on the car. Looked much better when the put new rubber on the back.

 

[quattro]

Checked with Rimmers - ET of the Vitesse wheel is indeed 40

Checked with Minilite; the wheels they offer for the P6 are the 6.0x14 Minilte traditional mag style wheel. The offset is ET30.

I have managed to get some longer wheel studs as the Vitesse nuts only do up 7 turns onto the standard SD1 studs. Many thanks Colin for letting me have some standard ones. The wheel nut bottoms out at 13 turns so at 12 turns with the longer one I seem to have the optimum wheel security with a margin of 1.5mm

Now I can't machine the wheels :shock:

D'oh!

 

[quattro]

You're not alone, when I took my old girl into her first MOT the guy pointed out that the rear tyres were different sizes! I thought it looked odd, had assumed it was a saggy spring on the car. Looked much better when the put new rubber on the back.

You wouldn't happen to know what is stampted on your wheels would you?

Like '5J FXN 14 RO' or whatever

Richard

 

[Demetris]

If it is of any use, the original steel wheels of my TC are stamped RO & CO, Made in England, 5 J FH- I .
The "I" after the dash is not very clear, and probably it could be anything else resembling "I".

 

[quattro]

If it is of any use, the original steel wheels of my TC are stamped RO & CO, Made in England, 5 J FH- I .
The "I" after the dash is not very clear, and probably it could be anything else resembling "I".

Thanks demetris, looks like I have a 2000 wheel.

I had two new tyres on the alloys last week, and the fitter told me that the wheel was a bit flaky inside. He cleaned them up and resealaed them.

The other three looked ok but were all going down slowly, so I took them down today to get them cleaned up too. He pointed out that the best looking one was dated week 37, 1992. The other two, which would have lasted a short while, were both dated week 23, 2002. :?

I was once told that a boat was a hole in the water, lined with wood, that you poured money into. I am beginning to think that a Rover P6 is a similar hole in the air!

 

[SydneyRoverP6B]

Hello Richard,

I know exactly how you feel when it comes to wheels.

In 2007 after much research and many questions asked, I purchased a set of Australian made Superlight wheels, which in appearance look just like the U.K miniltes. I was assured before hand by the manufacturer that the wheels would fit exactly the same as the original wheels, with suitable variations made given that the originals are 5.5J X 14 and the Superlights were 6.0J X 15.

I asked about the offset and was told that they would sit under the guards just like the originals.

Some 3 months later the wheels arrived, and they looked brilliant. I had them fitted to the car by the tyre centre to ensure clearance, and of course no problem..so far. I was told that once tyres are fitted, the wheel manufacturer is obsolved from all responsibility should a problem arise. Of course, you are not going to know there is a problem until tyres are fitted, clearance wise that is, and afterall I was assured that they would fit just like the originals.

Sure enough the rears did not fit,...the tyres coming into contact with the inside edge of the guards. The tyres were sized 205/60 HR 15.

The offset on these wheels was from memory 24P, nothing like the originals.... :shock: . I have never used them, they sit covered over in the garage. I'll sell them one day, maybe they will suit an SD1.. :?

Ron.

 

[quattro]

I was told that once tyres are fitted, the wheel manufacturer is obsolved from all responsibility should a problem arise. Of course, you are not going to know there is a problem until tyres are fitted, clearance wise that is, and afterall I was assured that they would fit just like the originals.

Sure enough the rears did not fit,...the tyres coming into contact with the inside edge of the guards. The tyres were sized 205/60 HR 15.

The offset on these wheels was from memory 24P, nothing like the originals.... :shock:

Hi Ron

They wouldn't get away with that over here.

The courts have some new legislation to work with and their new buzz phrase is 'fit for purpose.'

If someone supplies you a product which is not fit for purpose, then the supplier is made to pay for the goods, delivery, and any other costs that you have incurred; if you take them to court that is :?

I don't what the 'P' refers to but the offset on the Rover SD1 alloys is 40mm. Your wheels will sit 16mm further out than normal on the Sd1.

Richard

 

[quattro]

Why isn't anything ever easy?

I got a stud (M12 x 1.5 x 41mm) from a Ford dealer as most Fords nowadays use this type although there are different lengths available apparently.

The SD1 stud is an M12 x 1.5 x 33mm and if you use this, you will be able to do up your SD1 wheel nuts around 7 turns of the 13 available in the nut.

Using the Ford stud, you can do the nut up nearly 12 turns (13 without the wheel on) so I now have a securely fitted wheel with a small margin in the nut. (It's not going to bottom out)

Thing is, I only have 8 nuts so I get some new ones from Rimmer bros. They also have 13 turns of thread so you would think they would fit onto the Ford stud. Well they don't !!!

I have an M12 x 1.5 x 63mm competition stud and can thread this onto the Rimer nuts a full 13 turns, so why do they bottom out before they touch the wheel?

Because the thread on the reman nuts start in a different place as in the pic below.

The studs I have been playing with are as in the pic below

Left to right - P6 Stud, SD1 front stud, SD1 rear stud and the Ford 41mm stud.

So if you are fitting Vitesse wheels you can use the Ford studs and original SD1 nuts and get nearly 12 turns of thread.

Or, you can use SD1 studs and original SD1 nuts (If you get any) and get 7 turns of thread.

Or, you can use the Reman nuts and SD1 studs (front) and get just over 11 turns.

Word of warning though - what you cannot do is machine your wheel 3 - 3.5mm using standard SD1 studs, and then get a new set of wheel nuts as they will bottom out before they grip the wheel. :shock:

 

[Tor]

Hi Quattro,

As a matter of interest - it's been covered before, but have you tried SD1 front hub grease caps? I have the same setup waiting to be tried on the car, with SD1 studs as well. The caps are supposed to fit and sort that spacing issue you mentioned.

Regards,

Tor

 

[quattro]

Hi Quattro,

As a matter of interest - it's been covered before, but have you tried SD1 front hub grease caps? I have the same setup waiting to be tried on the car, with SD1 studs as well. The caps are supposed to fit and sort that spacing issue you mentioned.

Regards,

Tor

Nope I didn't know that and haven't tried it

yet

Thanks for the info.

 

[mrtask]

I've got the SD1 grease caps on the front hubs of my '73 parts car, and I can fit SD1 Vanden Plas 14" alloys that haven't been machined or relieved of material on the inner face. I don't know what studs are in the hub but I'll be pulling it apart sometime during the next couple of weeks, and I'll determine what length and thread they have and post some similar pics for comparison.