850 rear brake upgrade

[oblark]

As I have upgraded the front brakes with 320mm discs and Renault 4 pot brembo`s I thought it was about time I upgraded the rears.

Now I could go down the route of Porsche 4 pot rears but I`ve gone down the route of a set of these,





A set of very hardly used XC90 308mm discs and calipers,

All I have to do is to make a bracket to mount the XC90 calipers to the 850 caliper mounting point

[M-R-P]

you wanna sort that bloody steering column before you make it stop any quicker mate lol.

although the look on your face was a picture as the steering wheel sank into the dash

how long before its ready?

[oblark]

The steering column is on my list of jobs to do this weekend

Then on to making a bracket to use as a template,

Hopefully all should be done in time for the next southern meet

[cherry1809]

Mmm, pulls up a chair and watches with interest

[Tomcat]

Christ you're going to have a serious set of anchors on that thing aren't you?..Isn't there a risk of over braking the rear? after all you dont want to get the back end locking up every time you jump on the brakes do you?..

[oblark]

Christ you're going to have a serious set of anchors on that thing aren't you?..Isn't there a risk of over braking the rear? after all you dont want to get the back end locking up every time you jump on the brakes do you?..

Dalhousie has Porsche 4 pots on the rear of his 854 T5R and hasn`t had any problems



Also I will need damn good brakes when the forged engine goes in next year

[M-R-P]

If I remember correctly, the stop test on his MOT said there was a significant bias toward the front with his Brembo 4-pots so 308 single pot brakes on the rear should balance it all up nicely.

Better tyres might be a good idea tho lol.

[oblark]

If I remember correctly, the stop test on his MOT said there was a significant bias toward the front with his Brembo 4-pots so 308 single pot brakes on the rear should balance it all up nicely.

Better tyres might be a good idea tho lol.

And what is wrong with my tyres ?

[M-R-P]

Didn't say there was anything wrong with your tyres mate, but if you're gonna have that kind of stopping power, you'll want to know for sure the contact point with the tarmac is good.

[Tomcat]

I feel.....so inadeqaute... your back brakes are going to be bigger than my front's,lol...

[partsforvolvos.com]

quick question, have you checked the internal diameter of the drum ? i have it in my mind the the awd rear shoes might use larger spacers and fitting springs than a 2wd to make them further apart on one side.
not a problem , might just need different bits that's all.

[M-R-P]

Here's where it gets interesting...

Me, Rob and "He who shalt not be named" have been talking about this for a while (well, they've mainly been telling me to stop taking stupid pills and anything can be made to fit lol)

My rear disks and pads/shoes are due for renewal this year so I have a vested interest in this one...

[oblark]

"He who should not be named" is running xc90 discs with porsche brembos on his 850 and the discs just fitted over the hand brake shoe with no problems

[Biff]

Nice! They would do me the world of good on our roads.

[partsforvolvos.com]

I wasnt thinking about them not fitting over, but he didnt have to fit the xc90 shoes spacers to take up space?

smithy had me looking at every rear disc we have here to try and find one to fit his setup.

[oblark]

Here's where it gets interesting...

Me, Rob and "He who shalt not be named" have been talking about this for a while (well, they've mainly been telling me to stop taking stupid pills and anything can be made to fit lol)

My rear disks and pads/shoes are due for renewal this year so I have a vested interest in this one...

Before I fit these do you want to see if they`ll fit on yours ?

I wasnt thinking about them not fitting over, but he didnt have to fit the xc90 shoes spacers to take up space?

smithy had me looking at every rear disc we have here to try and find one to fit his setup.

I`m under the impression that the xc90 and 850 had the same size hand brake drum.

[M-R-P]

Before I fit these do you want to see if they`ll fit on yours ?

That's ok mate, I'm sure Steve will be waving another set at me soon lol

[oblark]

I`ve just found some xc 90 discs for £26ish each on ebay

[M-R-P]

you helped me blow my budget for the foreseeable

[oblark]

As it wasn`t raining when I got home i thought I measure the 850 and XC90 hand brake drums,

Both are as best as I can tell with a tape measure 175mm so thats that problem overcome

850 hand brake drum



XC90 hand brake drum