Jump to content
SAU Community

Recommended Posts

One thing Engineers ask if the dog bone would pass a 'destructive test' where the rotor is locked and a force is applied proportional to doing a 1G stop:

Assume vehicle weight is 1800kg (perhaps with 2 occupants etc.)

Single front wheel will experience a braking force of 0.8x 1/2 x 1800 = 720kg (0.8 is assuming 80% of braking force to the front brakes)

Based on an approximate 600mm dia tyre the torque generated will be 0.3x 720 x 9.81 = 2118.96 Nm

Assume disc rotor path is 298mm (outer dia and inner dia of approx 240mm), therefore mean effective radius is 136mm (rounded)

This translate to a torque of (Fxd = Fxd = 2119x296 = F x 136) therefore F = 4612Nm at brake rotor radius of 136mm

For bolt diameter calculations, don't forget there are two bolts, so divide this force by two to calculate the shear of the bolt and the approximate strength required and the revised radius of the torque acting on the bolts (smaller diameter...)

The destructive test for the dog bone bracket should be done at 2x force for safety factor and 3 times safety factor and the results recorded. FEA is non destructive and would allow theoretical tests to be done without breaking anything. Your engineer can perform this task and include the data in the report.

316 Stainless wont have the same strength as 4140, so the requirements of 12mm at any point and 7mm min thickness wont be applicable to this material.

If you are using factory brake calipers (from a larger or higher performing car) and bolting these on without dogbone adapters, then your engineer doesn't need to do the calculations, and therefore you save money when you get the certificate done!

Safety first gents..

sheebus. they must go through alot for this!

but like you say safety first

One thing Engineers ask if the dog bone would pass a 'destructive test' where the rotor is locked and a force is applied proportional to doing a 1G stop:

Assume vehicle weight is 1800kg (perhaps with 2 occupants etc.)

Single front wheel will experience a braking force of 0.8x 1/2 x 1800 = 720kg (0.8 is assuming 80% of braking force to the front brakes)

Based on an approximate 600mm dia tyre the torque generated will be 0.3x 720 x 9.81 = 2118.96 Nm

Assume disc rotor path is 298mm (outer dia and inner dia of approx 240mm), therefore mean effective radius is 136mm (rounded)

This translate to a torque of (Fxd = Fxd = 2119x296 = F x 136) therefore F = 4612Nm at brake rotor radius of 136mm

For bolt diameter calculations, don't forget there are two bolts, so divide this force by two to calculate the shear of the bolt and the approximate strength required and the revised radius of the torque acting on the bolts (smaller diameter...)

The destructive test for the dog bone bracket should be done at 2x force for safety factor and 3 times safety factor and the results recorded. FEA is non destructive and would allow theoretical tests to be done without breaking anything. Your engineer can perform this task and include the data in the report.

316 Stainless wont have the same strength as 4140, so the requirements of 12mm at any point and 7mm min thickness wont be applicable to this material.

If you are using factory brake calipers (from a larger or higher performing car) and bolting these on without dogbone adapters, then your engineer doesn't need to do the calculations, and therefore you save money when you get the certificate done!

Safety first gents..

Always good to have the input of an actual engineer wht510worship.gif. Definitely agree with your point regarding approval being easier if everything is a straight bolt up.

Mine didn't ask for a destructive test, and he inspected my handiwork prior to fitment, but obviously it had to pass a brake test, which I didn't include in my post. The numbers I included were just the ones for my particular experience.cheers.gif

how much would it roughly cost for a full test then?

i wouldnt assume it would be too pricey..

The Guy I used was only $300, for this; he'd do a whole car, but sadly, has retired now.

If you are using factory brake calipers (from a larger or higher performing car) and bolting these on without dogbone adapters, then your engineer doesn't need to do the calculations, and therefore you save money when you get the certificate done!

I knew there was another reason why I went Brembo instead of the Ake's :whistling:

whos really ever going to know that the brakes are non standard. i dont think you really need to bother getting it engineered, after all its just a volvo and no bodys going to look twice at it..

Today, I've fitted new tyres and got asked why i have nissan wheels on my Volvo..

This afternoon, hopefully i am getting the remainder for my car and i will no longer have a volvo!! maybe i'll come back in some years and get a pnm35 or something..

....whos really ever going to know that the brakes are non standard. i dont think you really need to bother getting it engineered, after all its just a volvo and no bodys going to look twice at it.......

I tend to agree, but the rule is to make sure people who have NFI are doing the right thing and getting it certified. Again, it's safer to spend a couple of hundred dollars to get it checked and PROVEN it's safe, than to assume...

I'd tend to agree if it was just bolting up larger factory brakes (Such as the V35 brembo type thing). Just make sure you use appropriate bolts and loctite etc.

Sorry for delayed replies, guys, but...

Whoa that's some serious camber wear, how much cambe you running?

No idea how much camber it was, but it was clearly too much! My neighbour did it last, I think, and *maybe* he didn't account for the extra weight of a wagon compared to his g/friend Anna (msnismo)'s R33 GTSt.

front or rear nick? might be too much toe in

These were rears, Iain. Was on the inside of the tyre, which is why I hadn't noticed earlier, despite me doing a quick (but obviously insufficient) check of the tyres fairly often. Surely toe-in would cause wear on the outside of the tyre, not inside, right?

That last pic looks like normal rear camber wear on an M35 with 235+ tyres :whistling:

Not nice, not nice at all but good you could get a lift home (no spare?)!

Mine's a C34, though... :whistling::P Yeah, thankfully StageIan chose just that night to also come along to the meet in his red s2, and he lives all of 2mins away from me. I had the spare, but with the difference in diameter (and lack of air until I got to the servo) it was causing major issues with the ATTESA.

good to hear you are OK Nick

+1. toe is more likely to cause excessive wear than camber.

Duncan, see my reply to zei-Iain above.

whos really ever going to know that the brakes are non standard. i dont think you really need to bother getting it engineered, after all its just a volvo and no bodys going to look twice at it..

Today, I've fitted new tyres and got asked why i have nissan wheels on my Volvo..

This afternoon, hopefully i am getting the remainder for my car and i will no longer have a volvo!! maybe i'll come back in some years and get a pnm35 or something..

I'm more worried about making sure my insurance is still valid *if* I ever have a crash, regardless of who's fault it was. Luckily for me, my old man is fairly proficient at waving spanners around and under a car (and occasionally throwing them at a wall when he gets the shits), so his help has been invaluable over the years. I've just recently gotten a set of R32 GTR front calipers too, so once I get the rears to match, I'll buy some new rotors and braided lines and tackle the swap.

So what's the deal with upgraded brakes? Do you guys want to track your cars?

To me it makes sense in a couple of ways:

1/ the standard brakes aren't great, I could get them to fade if I was out for a hoon. Not deadly dangerous, just not quite up to scratch

2/ stagea replacement brakes are hard to find and expensive. Over time something like a brand new ksport setup with easily and cheaply replaced discs and pads makes good sense. plus you get new braided lines thrown in for free

toe in will drag the inside more, toe out will do the outside more. it may be dfference depending on offsets and the car also.

but toe for sure. camber would wear differently

+1 on wheel alignment!

I'm more worried about making sure my insurance is still valid *if* I ever have a crash, regardless of who's fault it was. Luckily for me, my old man is fairly proficient at waving spanners around and under a car (and occasionally throwing them at a wall when he gets the shits), so his help has been invaluable over the years. I've just recently gotten a set of R32 GTR front calipers too, so once I get the rears to match, I'll buy some new rotors and braided lines and tackle the swap.

Thats actually a good point. i'm not too big on insurance and all that, but do know that they dont pay out when its a flood but not a f**kin gushing stream of water flood.. so i guess they'd try screw you out of an insurance claim too..

My insurance company is pretty good. Said that if I want to do a mod, as long as the car stays road legal and I let them know (which is as much for their protection as mine, because they get insured as non-standard accessories) they have no problems.

Think I'll do the GT-R upgrade then and get it engineered. What are people doing for the rears? Slotteds and good pads?

In other news, GOODIES!

IMAG0052.jpg

Nismo dash and slimline fan turned up today, but can't do anything with them until I get the car back :(

AM Performance are also going to tackle the intake pipe into the airbox, and looking at a couple of alternatives. Can't wait to pick the car up, should be awesome!

My insurance company is pretty good. Said that if I want to do a mod, as long as the car stays road legal and I let them know (which is as much for their protection as mine, because they get insured as non-standard accessories) they have no problems.

Think I'll do the GT-R upgrade then and get it engineered. What are people doing for the rears? Slotteds and good pads?

In other news, GOODIES!

IMAG0052.jpg

Nismo dash and slimline fan turned up today, but can't do anything with them until I get the car back :(

AM Performance are also going to tackle the intake pipe into the airbox, and looking at a couple of alternatives. Can't wait to pick the car up, should be awesome!

Be careful with the Suction pipe.

You'll find that under full load anywhere from 4000rpm + you may hit an air flow cut.

will feel like you've hit a brick wall for a split second

nismo dash is awesome :)

if i could get my 3 dials working id change that too!

Whats wrong with your 3 dials? My boost gauge isn't working, but I found a thread on Scotty's soldering fix, so I'll do that, get it working, then think about changing it :D

Be careful with the Suction pipe.

You'll find that under full load anywhere from 4000rpm + you may hit an air flow cut.

will feel like you've hit a brick wall for a split second

Why's that Aaron? Too much airflow? I'm confused... :wacko:

First time I heard that.

when I got my suction pipe made by scott it increases airflow dramatically.

I think Cam experienced it too.

as well as scott jethro craig etc.

our Air flow signal cuts the engine when it reaches 4.80volts through the air flow meter(correct if a different figure)

You'll need to get it tune, and have the airflow clamped to get it to stop doing it. with an emanage etc.

mine has a 3inch pipe custom made from the turbo outlet to the airbox. if your doing that, I guarantee you'll hit an airflow cut.. just be ready for it!

Edit: and yeh stock injectors will max out with the suction pipe mod, which isnt very safe!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Maf is a question mark but TPS  I have set at 0.47, the fact that I’m getting proper voltage range out of it with the key on leads me to believe it’s functioning properly. I’m getting proper voltages on basically everything. I still need to look up voltage ranges for z32 maf and test that 
    • Honestly no not at all, but it’s a very basic tune, it’s stock injectors q45 tps and z32 maf. Other than that it’s a completely stock base map. The file is from nistune and from my understanding if it was tune related I would be able to unplug maf and tps and it would still start even if it was a really shitty start. I have tried starting it with coolant temp, maf, and tps unplugged none of those 3 togethor or individually changes anything 
    • 🏆 Skyline Supremacy Meets Mount Panorama Magic 🏆 Join SAU NSW as we take the long way to Bathurst, the home of GTR greatness. Saturday 30th August 2025 7:00AM Meeting Hanna Park North Richmond 7:30AM Departure Cruise Via Bells of Line Road 9:00AM Arrival to Stop 1: Golden Poplars Meadow Flat 9:45AM Arrival to Final Destination: Mount Panorama Motor Racing Circuit Meet Location: Hanna Park North Richmond Stop 1: Golden Poplars Meadow Flat Final Destination: Mount Panorama Motor Racing Circuit   *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
    • What does it look like with highway driving? And yes, I had a similar thought as Duncan. It looks quite similar in my Stagea and I have made myself accept it as normal. Might have to look into it some day   Highway gets as low as 10l/100km on my end so I'm not as worried about it being a mechanical issue. More likely just the tune on the haltech.
    • While I was waiting for the new parts to come in for the charge pipe and radiator I decided to do some turbo modification. The drive pressure (exhaust backpressure) was a lot higher that I thought it should be. For 32lbs of boost drive was 55lbs. The turbine housing is a 1.10AR and my turbo builder has suggested to go to a 1.25AR. To test if a larger AR would do anything to reduce drive pressure AND not spend any money I decided to hog out the divider in my current housing. I removed it from the inlet and the whole way through the housing.  After reassembly and testing it doesn't look like this modification did anything for reducing drive pressure or requiring more fuel (making more power). Oh well, it was worth a shot. We'll get some data at the track if it makes it past the 60ft. I also machined a $7 shift knob off Amazon to fit my Stillway shifter since I didn't like the Stillway shift knob. Next on the list was the radiator replacement and fabrication of a new intercooler tube that had no silicon coupler. No pictures of this - I was short on time each night after work to get this done and didn't stop to take pictures.  Next was to get the clutch disks out and replaced. Previously when installing the dogbox I had ordered a set of the same sintered iron disks I had been running because I switched to the 26-spline input shaft. I thought it was odd that they didn't have any markings or brand name on them like all my old disks had but installed them anyway. At the track I could not get the clutch to lock up using my normal strategies. After two track nights I reached out to the clutch manufacturer and ask their thoughts. They said they had to switch the material out because they were having trouble getting the original material and that this new material would not take to being slipped very well.  So out with the first set of 26-spline disks and in with the correct material 26-spline disks. While I had the trans out I added an inspection/service hole. I've wanted one of these for a while. Now I can have a look at things and change the front cover shimming when needed (clutch wear). I hustled and got the clutch change done in a few hours on a Saturday. Hopped in the car and drove home. On the way home I did a 1-3 pull. When shifting from 2nd to 3rd the core plug in the back of the cylinder head popped out and dumped all the coolant. Thankfully I was only 30 seconds from home and coasted it there. Datalog showed nothing unusual and 2.5psi of coolant pressure. That plug has been in there since 1992 but I guess it worked its way out. Pulled the trans AGAIN and replaced the plug, JB welded it in, and made a brace. Also deleted the head drain I had added in during the bearing issue fiasco.  I am currently changing my boost control plumbing to make it cleaner. After that is done I'll make another attempt at getting past the 60.
×
×
  • Create New...