PCD? Ofset? what do they really mean?

[EYV65]

Okay, so im not the brightest star in the sky, so please bare with me...

So, i currently have a minor with Ford disc brakes so has ford PCD, which i believe is 108mm? Anyway, it currently has 13" mag slot (horrible) and i would like 14" wheels to look like moggie wheels.

Im getting very confused about the whole ofset thing? is this the depth of the wheel from the back? and what does this really mean when it comes to buying wheels. I have found some classic smoothie wheels which are basically similar in style to minor wheels, but im worried that i could buy myself a load of problems!!

General information on the ofset thing for complete understanding would be helpful.

thank you

[philthehill]

The PCD is the distance between the wheel studs.

The PCD of a Morris Minor is 4".

Are you absolutely sure that you have the Ford PCD arrangement on your front hubs. The Ford disc brake calipers are separate to the PCD and your hubs may have the Minor 4" PCD.

The PCD is nothing to do with the off-sett of the rim of the wheel.

Off-sett is the relationship between wheel centre and rim. For example 6J off-set means that the rim is off-set 3" either side of wheel centre.

https://konigwheels.com/wheel-info-tech/what-is-pcd/

[EYV65]

Yes definitely ford pcd it has the ford vented brakes with mag slot wheels, plus it has a ford back axel.

but what does the offset mean? when looking for new wheels what is with the offset... do i need to worry about it?

[philthehill]

Yes you do need to at least take into account the off-set of the wheel and what direction the off-set takes.

https://www.tsw.com/explore-tsw-custom- ... offset.php

[dp]

Just to add another parameter to consider, the centre bore. That's the diameter hole in the middle of the wheel through which the front hub sticks. Obviously if the centre bore is too small it won't fit on but if it's too big the wheel won't be held properly and the wheel studs will be taking all of the strain.

https://www.tyresdirectuk.co.uk/faq/wheel-size-guide/

[kevin s]

As said above Offset is the distance from the face the wheel bolts to the hub to the centreline of the wheel, so if the mounting face is in the centre you have zero offset, if it is nearer the outside of the wheel it is positive offset, nearer the inside negative offset.

Usually you would try to select wheels with similar geometry to the original this is because the suspension is usually designed so the steering axis passes close to the centre of the tyre, add excessuve offset and it will pull on ruts cambered roads etc., it can also increase the loads on the suspension components.This obviously assumes that whoever has made your hubs kept the original geometry.

[EYV65]

Thank you, much more understanding

So what is the offset for a minor?

[taupe]

The PCD is the distance between the wheel studs.

The PCD of a Morris Minor is 4".

Above needs clarifying....

PCD is Pitch Circle Diameter so it is the diameter of a circle that goes through the centre of each stud.

This is clear from the diagram in the link provided in Philthehills post

If you measure the distance between the centre of two adjacent studs you will get the wrong figure so to be clear ..... it is the distance between two diagonally opposite studs that you must measure on a four stud wheel like on the standard Minor...(it is obviously more difficult to measure on a 5 stud wheel as no studs are opposite each other)

Taupe

[philthehill]

With a five stud arrangement use the formula in the link above to determine the PCD.

Here it is again:-

https://konigwheels.com/wheel-info-tech/what-is-pcd/

[EYV65]

I measured the commercial wheels the other day and they most certainly are not zero off set!! from hub face to front (outer) of rim measures 1.5" and from hub face to back (inner) rim measured 4.5 not adding up to a Zero off set like some people think.

So what is the off set of morris minor wheels? What is meant to be correct? has someone got it in a book, because is cant find it

[jaekl]

4.5in rear offset? Will they work on the front? Don't the 800cwt van wheels add most of the extra width to the outside?

[Steve Phillips]

Hi All

I have just measured two standard minor 1000 wheels, They both show a positive offset, i.e the wheel clamping face is nearer the outside (front) of the wheel, I measured 1 riveted wheel and one welded wheel the offset measured 3 3/8” on the welded rim and 3 ¼” on the riveted rim, now I didn’t know there would be a a difference between the two, and as they are scrap wheels that are 40+ years old there’s nothing to say they are 100% accurate, but we are only talking 3mm – 1/8” difference.

Now LP917 rims (4 ½” van rims) have a positive offset of 1 5/8” or 41mm, yes they will fit front and back of any std minor 1000 (I have had them fitted in the past)

Hope this helps,

Steve

[SteveClem]

I’m told that van rims are good for taking 165 tyres. Well, that’s what I’ve been using for the past ten years,after advice on here. The car sits well on them.

[philthehill]

If the hubs are PCD for Ford wheels the offset of the Morris wheel is irrelevant as they will not fit.

You need to find wheels that fit the Ford PCD with clearance for the Minor swivel.

With a clearance distance of 4" between the outer face of the hub (the face onto which the wheel is secured) and the unused (upper steering arm boss) a 7J x 13" wheel will fit without fouling as shown in the photo below.

7J x 13" also fitted to the rear with a 3/8" spacer.

Both front and rear hubs have a PCD of 4".

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