Rabin Posted April 25, 2009 Report Share Posted April 25, 2009 Are those Porsche 996 / Boxster S rear Brembo calipers?I've just picked up a set of Boxter S calipers for my 505 Turbo project car, and was thinking the set would be a sweet set up on the V70R as well. If the install goes well on the 505 Turbo, I'll start searching for a set for the V70R - disk size is virtually the same between the two cars now.Rabin Link to comment Share on other sites More sharing options...
lookforjoe Posted May 2, 2009 Report Share Posted May 2, 2009 Are those Porsche 996 / Boxster S rear Brembo calipers?I've just picked up a set of Boxter S calipers for my 505 Turbo project car, and was thinking the set would be a sweet set up on the V70R as well. If the install goes well on the 505 Turbo, I'll start searching for a set for the V70R - disk size is virtually the same between the two cars now.Rabin996 front calipers, S60R rotors Link to comment Share on other sites More sharing options...
Rabin Posted May 2, 2009 Report Share Posted May 2, 2009 996 front calipers, S60R rotorsThat's for the REAR BBK? Sounds like a great setup for the front... Can't see it working on the back with the stock master cylinder. Rabin Link to comment Share on other sites More sharing options...
NChoy Posted May 2, 2009 Report Share Posted May 2, 2009 That's for the REAR BBK? Sounds like a great setup for the front... Can't see it working on the back with the stock master cylinder. RabinNo, that's the fronts. Rears are a bit more challenging... need S60R rear rotors and calipers, but a special bracket needs to be fabbed up. Link to comment Share on other sites More sharing options...
Scandia1568908312 Posted May 2, 2009 Report Share Posted May 2, 2009 I'll be getting the Olive back here pretty quick. From what I can tell the tranny is starting to have issue's. delayed engagement into drive. So I'll definitely be interested in a break down of your swap. From how hard it was to locate all nec parts, to any custom creative modding you had to do. .............Dave Link to comment Share on other sites More sharing options...
lookforjoe Posted May 3, 2009 Report Share Posted May 3, 2009 No, that's the fronts. Rears are a bit more challenging... need S60R rear rotors and calipers, but a special bracket needs to be fabbed up.No, the rears are 996 front calipers, S60R rear rotors & Aaron's brackets. I already went through this with Aaron. S60R rear calipers can't be made to fit the AWD axle. Porsche calipers bolt from the top, not from the side like Volvo calipers. like this...The bracket is a right angle adaptor like IPD's front bracket. these are the 996 calipers - look at the size of them. Link to comment Share on other sites More sharing options...
Rabin Posted May 3, 2009 Report Share Posted May 3, 2009 996 calipers are the same physical size front and rear - just with different piston sizes aren't they? (I don't have mine yet.)On the V70R - I'm shocked that front 996 calipers with the big pistons are going to work with stock master cylinder on the rears - or is upgrading the master part of the upgrade as well? What calipers are running on the front? (Look like the Porsche "Big Blacks")That's some crazy braking force if it all works to plan. I'm using 996 front and rear calipers - but that car weighs 1000lbs less than the V70R so it still should stop quite well.Rabin Link to comment Share on other sites More sharing options...
lookforjoe Posted May 3, 2009 Report Share Posted May 3, 2009 996 calipers are the same physical size front and rear - just with different piston sizes aren't they? (I don't have mine yet.)On the V70R - I'm shocked that front 996 calipers with the big pistons are going to work with stock master cylinder on the rears - or is upgrading the master part of the upgrade as well? What calipers are running on the front? (Look like the Porsche "Big Blacks")That's some crazy braking force if it all works to plan. I'm using 996 front and rear calipers - but that car weighs 1000lbs less than the V70R so it still should stop quite well.RabinThat explains why the pads are the same dimension. But, Aaron said the numbers that work are 996-351-425 & 426 - the rears are 352-421 & 422 - don't know if the offset, etc., is the same.The pistons are 33leading/38trailing, intended for rotor thickness 31mm.I bought mine with hardware to save having to buy extra new hardware..Just have to figure out which pads will work, since we don't need the extra expense of sensors.. Link to comment Share on other sites More sharing options...
Rabin Posted May 3, 2009 Report Share Posted May 3, 2009 Can you confirm what you're running for front calipers? (or are you running front calipers at both ends?) The 996 front 33 / 38 mm calipers on the rear of the V70R seem like they'd be too big when combined with a BBK up front - but I've not checked out what the Volvo stock calipers are sized at so I'm just guessing. I'd be curious to see how the master cylinder works with the new calipers and what your pedal feel is like. Do you know what the V70R master cylinder bore is? Can you give me the rough dimensions of the rear rotors as well? (I thought the dimensions you provided are the fronts... If those are dimensions for the rear rotors that's impressive!On my other car - I'm running the complete Boxster S set up (booster with master (25.4mm bore VS the 19mm) with the calipers and hoses. I figure installing the complete system saves me a lot of grief - and I'll install a brake bias control for the rear just to make sure I can dial it in perfectly. Gonna try and run them on 302x28mm front rotors and 300x22mm rear vented rotors. Hoping to still be able to fit 16" rims thus the 302mm rotors. Should be plenty for a 2800 lb car though.Rabin Link to comment Share on other sites More sharing options...
Rob Karloff Posted May 3, 2009 Report Share Posted May 3, 2009 No, the rears are 996 front calipers, S60R rear rotors & Aaron's brackets. I already went through this with Aaron. S60R rear calipers can't be made to fit the AWD axle. Porsche calipers bolt from the top, not from the side like Volvo calipers.You mean the Porsche calipers use radial mount whereas the stock Volvo use axial mount I would be very surprised if the stock master cylinder had enough fluid volume movement to satisfy the piston area. The stock calipers do not have that big a piston really. Has anyone ever actually sat down and worked out the piston areas to see? I would imagine you'd certainly need a good adjustable bias valve, plus locking the rears for any length of time would be bad for the viscous unit. Link to comment Share on other sites More sharing options...
lookforjoe Posted May 3, 2009 Report Share Posted May 3, 2009 You mean the Porsche calipers use radial mount whereas the stock Volvo use axial mount I would be very surprised if the stock master cylinder had enough fluid volume movement to satisfy the piston area. The stock calipers do not have that big a piston really. Has anyone ever actually sat down and worked out the piston areas to see? I would imagine you'd certainly need a good adjustable bias valve, plus locking the rears for any length of time would be bad for the viscous unit.Rob, the viscous unit is de-coupled on braking/decel - you didn't know that? That's what the freewheel unit is designed for.Nick's car is already running this setup.Can you confirm what you're running for front calipers? (or are you running front calipers at both ends?) The 996 front 33 / 38 mm calipers on the rear of the V70R seem like they'd be too big when combined with a BBK up front - but I've not checked out what the Volvo stock calipers are sized at so I'm just guessing. I'd be curious to see how the master cylinder works with the new calipers and what your pedal feel is like. Do you know what the V70R master cylinder bore is? Can you give me the rough dimensions of the rear rotors as well? (I thought the dimensions you provided are the fronts... If those are dimensions for the rear rotors that's impressive!On my other car - I'm running the complete Boxster S set up (booster with master (25.4mm bore VS the 19mm) with the calipers and hoses. I figure installing the complete system saves me a lot of grief - and I'll install a brake bias control for the rear just to make sure I can dial it in perfectly. Gonna try and run them on 302x28mm front rotors and 300x22mm rear vented rotors. Hoping to still be able to fit 16" rims thus the 302mm rotors. Should be plenty for a 2800 lb car though.RabinI have IPD's BBK - 928 calipers. S60R front rotors. The braking is great - no real fade from 100+ - stopping after drag strip 1/4" mile runs is no issue. I have no idea on the master cyl specs. The rear rotors are S60R AWD - you should find the specs online. The 996 calipers & pads are smaller than the 928 fronts. 17" is the minimum that will fit over the BBK. Link to comment Share on other sites More sharing options...
Rabin Posted May 4, 2009 Report Share Posted May 4, 2009 Holy cow... I looked at the 928 S4 calipers as well and they're using even bigger pistons... 38/44 if I remember correctly. Pad is also 132mm long VS the 996's 118 mm. So the 996 rears will suit well as far as the front / rear balance - I'm just shocked the MC works with both these calipers. BTW - the 928 S4 used 304 mm rotors with 16" wheels which is why I wanted them. Got a smoking deal on the 996/Boxster set up though and went with that.Good to know for future reference for my V70R though! Will have to keep an eye out for another set up for future use on the wagon for later.Good luck with your upgrade - brakes should be amazing.Rabin Link to comment Share on other sites More sharing options...
Rob Karloff Posted May 4, 2009 Report Share Posted May 4, 2009 Rob, the viscous unit is de-coupled on braking/decel - you didn't know that? That's what the freewheel unit is designed for.I did, but if you read the text properly and look at the design of the freewheel, you'd see this applies only when the front wheels start to lock and the rears continue to drive (which on the factory system is what would always happen). If you are moving forward and lock the rears only, you would be in effect applying power to the viscous almost as if you'd done a standing start and dumped the clutch at 4k RPM and zinged up the front wheels. And if you'd locked the rears up on braking then the viscous output could not move at all (whereas on a launch it can put the output force into the wheels and overcome rolling resistance to accelerate the rear), so in a quick instant you could cook the viscous itself.See what I mean? Link to comment Share on other sites More sharing options...
lookforjoe Posted May 4, 2009 Report Share Posted May 4, 2009 I did, but if you read the text properly and look at the design of the freewheel, you'd see this applies only when the front wheels start to lock and the rears continue to drive (which on the factory system is what would always happen). If you are moving forward and lock the rears only, you would be in effect applying power to the viscous almost as if you'd done a standing start and dumped the clutch at 4k RPM and zinged up the front wheels. And if you'd locked the rears up on braking then the viscous output could not move at all (whereas on a launch it can put the output force into the wheels and overcome rolling resistance to accelerate the rear), so in a quick instant you could cook the viscous itself.See what I mean?But, my front brakes are still substantially larger than the rears, and the rears only get 20% (?) of the braking - I don't see it being an issue. Link to comment Share on other sites More sharing options...
Rob Karloff Posted May 4, 2009 Report Share Posted May 4, 2009 But, my front brakes are still substantially larger than the rears, and the rears only get 20% (?) of the braking - I don't see it being an issue.Fair enough, so is that on the stock proportioning system? If so, is there really a noticeable increase in braking ability/performance? I'm guessing it's a fair cost/weight penalty to fit these rears which might not be worthwhile...? I figured to get any real benefit from these you would have to fit an adjustable bias valve and tune until you had the brake balance optimal, which was why I was making the point about the consequences of locking the rears up (I figured most people could imagine the stability/handling consequences of that but might not think about the poor AWD system!).I did consider fitting the MY2000 stock vented brakes to my 98 alongside my front Porsche BBK, but I really couldn't see even that giving more actual braking performance except on the track under repeated hard use with little cool-off time. The front BBK is a no-brainer really, despite the weight/costs of it you're going to have hugely better braking from it. But I wonder about the rears given how little of the braking they actually do. All interesting stuff tho, and if you say it's noticeable and worthwhile then I'd believe you Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.