V70 R Brake conversion questions...

[deeman940]

Originally Posted by ~Goose~

I'm wondering what this means off the retro turbo site, re the Alfa brake conversion..

"This is excellent alternative to 4 pot S60R conversion which many times proven to be unsafe".

Didn't see that bit! He does say in the description for the S60r brackets for 336mm discs that you have to send the calipers to him for machining. He must know something we don't.....I would trust his opinion. I would like to know why they are dangerous though....
On another note....I did speak with someone today about an AP Racing kit. He said it was possible but would need a hub, a wheel and a track rod end as he had never done a 940 before...there was no charge (for the R and D) they will just add it to their range...which I thought was great, only problem is the price at around £1500. I am still tempted I must admit...I have always wanted some AP brakes, those black and yellow calipers look sooo sexy!

[rogerthechorister]

I'm pretty amazed at the thought that 302s will not provide enough stopping power. I find that Chinabay drilled and grooved discs or Black Diamonds (standard size) sometimes with sexy pads give plenty of retardation although I am still chasing some judder and weave issues, and I am not a slowcoach.

How fast do you want to go?

[deeman940]

Originally Posted by rogerthechorister

I'm pretty amazed at the thought that 302s will not provide enough stopping power. I find that Chinabay drilled and grooved discs or Black Diamonds (standard size) sometimes with sexy pads give plenty of retardation although I am still chasing some judder and weave issues, and I am not a slowcoach.

How fast do you want to go?

Not a case of how fast I want to go but how late I want to brake. Men, in terms of performance/ power do not like to go backwards...myself included!
I have had a very light Nissan Silvia which had R33GTR Brembos all round, the stopping power was as immense as its 375 bhp...I would like to match this if possible...or as close as I can!!
My car now handles like a proper sports car, I would like it to brake like one also if I can!

[rogerthechorister]

Not sure I agree with your science. Increasing disc size does two things. It gives the brake pads more leverage (so it will be easier to lock the wheels) but if you can already lock the wheels - if you disable your abs you can find out - and I suspect you can - that is not the critical path. The second thing is that it increases the heat dissipation (as does drilling and grooving) and the amount of heat you need to dissipate is half em vee squared (kinetic energy) and that depends on how fast you are gong (and what you weigh). As you know inadequate heat dissipation can result in brake fade, which is very alarming.

[deeman940]

Originally Posted by rogerthechorister

Not sure I agree with your science. Increasing disc size does two things. It gives the brake pads more leverage (so it will be easier to lock the wheels) but if you can already lock the wheels - if you disable your abs you can find out - and I suspect you can - that is not the critical path. The second thing is that it increases the heat dissipation (as does drilling and grooving) and the amount of heat you need to dissipate is half em vee squared (kinetic energy) and that depends on how fast you are gong (and what you weigh). As you know inadequate heat dissipation can result in brake fade, which is very alarming.

LOL,,,there is NO science involved at all!! only previous experience....
Bigger caiipers and disc size works, it stops you faster and more effectively with less fade....
When I first owned my R32 Skyline GTR the brakes were quite good but would suffer horrific fade with heavy use...The disc size is small due to 16" standard wheels. .I had some brackets made for the standard calipers to accept M3 size discs and the problem was solved, brakes were MUCH better and I did not experience and fade ever again....job done.
My discs are horrifically warped at the minute due to overheating which tells me they are nowhere near up to the job!

[barkster1971]

Discs are 330mm not 336mm for v70r/s60r calipers. As I'll be putting in a 2.5 16v big turbo engine in I feel these will suffice. 302mm discs with the V70 calipers are a nice upgrade and will be enough for 95% of the time.
I will be putting the bigger back discs on (310mm?) with the rear v70r calipers so will not be using stock rear discs (obviously).

[ralph s]

hi all
i have a 1999 v70r phase 3 & was wondering if i change my rear vented 288mm discs--& put 295mm vented discs on can you keep the same caliper ?? will it fit the slightly bigger disc.
thx in advance.

[360beast]

Originally Posted by ralph s

hi all
i have a 1999 v70r phase 3 & was wondering if i change my rear vented 288mm discs--& put 295mm vented discs on can you keep the same caliper ?? will it fit the slightly bigger disc.
thx in advance.

Hiya this is the 7/900 series section and the thread is discussing fitting V70 brakes to a 940.

If you put a post in here

https://www.volvoforums.org.uk/forumdisplay.php?f=16

That is the right section for your car and you will be much more likely to get a response, good luck

But to answer your question, no I don't think so as brake discs run very close to the calipers so adding 7mm on might just be enough to make it touch the caliper.

[Laird Scooby]

Holy thread resurrection Batman!

For the sake of 7mm extra diameter (3.5mm radius) on the disc, the work involved wouldn't be worth it. Given the extra radius is only 3.5mm, it's possible the existing caliper might clear the disc enough to do it but the pads would be the same with the edges of the pads at the same distance from the centre so would still only exert the same moment of torque on the disc towards slowing it down.

Overall gain, nothing in terms of braking and a net loss to your wallet and possibly street cred for doing a useless mod.