Hi,

 

Need an explanation of PCD, offset and how i calculate area needed for brakes as i want to know what size i can get behind my volks TE73 17 inch wheels.

 

any links, advice would be great

 

Tar, Ste

You need to find out whether the design of the inner wheel face can accommodate the callipers as well as whether the wheel diameter can. PCD and offset of a wheel won't really dictate what brakes you can have. Calliper design/size, hub sizing, centre bore and disk design will.

 

Different styles of wheels of the same diameter and offset+width will accept different types of brakes and vica versa. You'll only really know of any contacting surface once you trial fit the wheels, unless you get data sheets for the brake callipers, work out how far the inner part of the spoke is from the hub and compare to the dimensions of the calliper and its mounting point on the lower part of the strut.

 

What brakes are you wanting to fit?

If you want some info on PCD, click the link. http://www.300zx.co.uk/forums/showpost.php?p=1134648&postcount=2

You need to find out whether the design of the inner wheel face can accommodate the callipers as well as whether the wheel diameter can. PCD and offset of a wheel won't really dictate what brakes you can have. Calliper design/size, hub sizing, centre bore and disk design will.

 

Different styles of wheels of the same diameter and offset+width will accept different types of brakes and vica versa. You'll only really know of any contacting surface once you trial fit the wheels, unless you get data sheets for the brake callipers, work out how far the inner part of the spoke is from the hub and compare to the dimensions of the calliper and its mounting point on the lower part of the strut.

 

What brakes are you wanting to fit?

 

I believe you told me a wile ago how to work them out, i just can't find it.

 

I'm thinking about the k sport 6 or 8 pot calipers, its the size of the disc that concerns me, need a set up that will withstand the occassional track day.

 

Also what would be the best setup for a regular track day car?

 

Thanks,

Thankyou for the link

There's a difference between working out the offset and working out how much distance there is between the inner wheel face, which is the inside of the spokes and the hub. This won't be the centre-line of the wheel (which is what you use for measuring offset).

 

It's the caliper that you want to be more concerned about over the disk size.

 

I can't answer the last bit though as I never track my car and currently have stock brakes.

 

I believe you told me a wile ago how to work them out, i just can't find it.

 

I'm thinking about the k sport 6 or 8 pot calipers, its the size of the disc that concerns me, need a set up that will withstand the occassional track day.

 

Also what would be the best setup for a regular track day car?

 

Thanks,

With 17's definatly no bigger than 330mm , and only some 17's would fit, all depends on the size of the calipers and the particular spoke design of the wheels. I know that having tried myself 4 different sets of 17's none of them would fit over some 350z Brembo's....but there are some 17's that do.

 

For the occasional track day you could get away with the GTR/350z/Evo Brembo setup, with a decent set of pads

 

But for regular track work they wont cut it. The K-sport's are actually getting a good reputation, plenty of folk are happy to criticise becuase of the cheap chinese/taiwanese origins though. Then there is the big name reputable brands - AP Racing, Stoptech, Rotora,

Edited October 11, 200817 yr by Yowser

Are Brembo's not in your list of

big name reputable brands

Are Brembo's not in your list of

Brembo dont offer a bolt on "kit".

 

The brembo's I did mention (GTR, 350z, Evo..etc) , are standard factory fit items that will fit the 300zx (some straight fit, some with brackets already designed by others), but are not suitable for serious track work - Thats why there are so many available 2nd hand.

 

You could adapt a bigger Brembo kit to fit (F40, porsche, range rover..etc), from another vehicle, but it gets all "custom" then.

Edited October 11, 200817 yr by Yowser

There's a difference between working out the offset and working out how much distance there is between the inner wheel face, which is the inside of the spokes and the hub. This won't be the centre-line of the wheel (which is what you use for measuring offset).

 

It's the caliper that you want to be more concerned about over the disk size.

 

I can't answer the last bit though as I never track my car and currently have stock brakes.

 

Would it be correct to say the offset is the difference between the centre line of the alloy and the line where the alloy mounts to the hub, so that you could change this by shimming in between the hub/disc and the alloy.

 

Have you got a any links for how that affects suspension geometry?

 

Thanks again for bearing with me!

Yes. You can shim with spacers. I have 20mm bolt-on hubcentric spacers on mine, but that's only really for aesthetics. Aids handling a little too.

 

Spacers don't really effect the geometry, the camber and toe are for that. It exaggerates any shortfalls in these though.

Brembo dont offer a bolt on "kit".

 

The brembo's I did mention (GTR, 350z, Evo..etc) , are standard factory fit items that will fit the 300zx (some straight fit, some with brackets already designed by others), but are not suitable for serious track work - Thats why there are so many available 2nd hand.

 

You could adapt a bigger Brembo kit to fit (F40, porsche, range rover..etc), from another vehicle, but it gets all "custom" then.

 

I have a inner diameter of 370mm and around 120mm or there abouts from the hub face to the back of the alloy, I was considering having an 8 pot caliper set with 330mm discs on the front and 6 pot 330mm on the back.

 

i realise with the wheel size i have won't be adequate for larger brakes that i'll need for regular track days and i'll have to buy some new alloys for the track use. If i can get away with this in the interim with the z i have, i'm planning a project with another slicktop for track only use. It'll ween me onto track driving gradually.

 

What would be the best/competent track brake setup?

 

 

.

A while back you identified my alloys as Volks Rays TE37 - they seem to have enough space, just! What kind of margin is needed for metal expansion with the heat produced?

 

Cheers,

Edited October 11, 200817 yr by stenorth

PCD means 'pitch circle diameter' which refers to the bolt / stud fixings of the wheel and have no relation to the offset. Obviously when buying wheels you need to ensure that they will fit a Zed relative to the wheel fixings. The offsets only come into play when considering calipers / disks and appearances.

PCD means 'pitch circle diameter' which refers to the bolt / stud fixings of the wheel and have no relation to the offset. Obviously when buying wheels you need to ensure that they will fit a Zed relative to the wheel fixings. The offsets only come into play when considering calipers / disks and appearances.

 

Cheers, wanted to know as seperate bits of information, so what would pcd of 114.3 relate to?

 

Tar,

The stud spacing. You should have a '5x' before that. Hinting that it's a 5 bolt stud pattern at 114.3mm diameter.

Edited October 11, 200817 yr by FunkySi

The stud spacing. You should have a '5x' before that. Hinting that it's a 5 bolt stud pattern at 114.3mm from bolt centre, to the centre of the hub.

 

Aha! i understand now, so it's a radius to bolt centre then and the five stud pattern would be five bolts at 72 degrees apart.

 

Thank you once again

Sorry, I re-wrote it. Not sure why I put that up.

 

Basically, if you had a 5 stud pattern layed out and drew a circle through all points of the centre of the bolt holes and measured the diameter of that circle, that would be the diameter measurement.

Cheers, wanted to know as seperate bits of information, so what would pcd of 114.3 relate to?

 

Tar,

 

A Zed...;)

...here's a crude MS Paint drawing I did to illustrate.... bolt holes in black, the red indicating the diameter. Edit....which now look purple! LOL

 

Sorry, I re-wrote it. Not sure why I put that up.

 

Basically, if you had a 5 stud pattern layed out and drew a circle through all points of the centre of the bolt holes and measured the diameter of that circle, that would be the diameter measurement.

 

Was thinking about it, the spacing and 228mm diameter for the studs would be to big, it's late lol, thanks for bearing with.

 

So if above word "radius" is replaced with diameter, it would be correct.

 

Thank you,

A Zed...;)

 

my next question! :p

Was thinking about it, the spacing and 228mm diameter for the studs would be to big, it's late lol, thanks for bearing with.

 

So if above word "radius" is replaced with diameter, it would be correct.

 

Thank you,

 

 

No, not radius, see 'my crappy diagram'.

ere you go

 

http://www.needforspeed.co.uk/htmlpages/TechWheels.htm

ere you go

 

http://www.needforspeed.co.uk/htmlpages/TechWheels.htm

 

Exactly what i wanted, i thank you!

Stephen,

 

I e-mailed you the exact dimension of the KSport kits some time ago but for the sake of clarity, here the are again:

 

KSport 330mm w/6 or 8-pot calipers: requires 374mm diameter clearance

KSport 356mm w/6 or 8-pot calipers: requires 400mm diameter clearance

 

This means that from the centre line of the alloy you'll need 187mm either side for a 330mm kit. Basically, take the diameter of the disc and add about 20mm to account for he caliper.

 

My supplier currently has stock of KSport brakes to suit the 300ZX so give me a shout if I can be of assistance.

 

Regards,

 

Dan