You beauty!.........through engineering - Page 2

Luke Gillett · #1 (**permalink**) 10-29-2007, 12:27 PM

Well done Slowy
Not long to go now.

All the best,
Luke.....

CHANMADD · #2 (**permalink**) 10-29-2007, 01:16 PM

I use Series 1 Jag front calipers(3 piston),you could put a spacer between the caliper halves to account for the thicker vented rotor which would be much less money than Wilwoods or the like and they work!!,and a Alfasud pedal box assembly with master cylinders and my brake balance is near perfect.

400TT · #3 (**permalink**) 11-09-2007, 06:03 PM

Stephen, better late than never. My pedal ratio in the RMC is 4.1:1, which is bang on the money in my books for a boosted system.

Did you get a chance to measure your pedal ratio?

stephen low · #4 (**permalink**) 11-10-2007, 05:54 AM

Craig

Hadn't got around to measuring my pedal but I will tomorrow.

But for clarity from where to where did you take the measurements on the brake pedal?

Am I right in saying centre of pivot point to centre of brake piston versus pivot to end of pedal?

Let me know and I can make the same and thus comparative measurements.

Cheers

Steve

400TT · #5 (**permalink**) 11-10-2007, 02:56 PM

Quote:

Originally Posted by stephen low

Am I right in saying centre of pivot point to centre of brake piston versus pivot to end of pedal?

Yep, that's it.

stephen low · #6 (**permalink**) 11-11-2007, 02:00 AM

Craig

Measured my ratio at 4.3:1 so not much different you your set up.

Thinking about this, setting a lower ratio by moving the booster connection point closer to the pedal pivot ie requiring more pedal pressure for the same outcome wont change the effect at the wheels as far as I can see.

So you need more pressure but are still only achieving the same effect at tyre, I think your suggestion re reduced piston size might have more merit.

Still think I need to see a brake specialist!

Cheers

400TT · #7 (**permalink**) 11-11-2007, 02:10 AM

Pedal ratio has a significant effect on brake feel & performance. Don't underestimate it.

But your pedal ratio is in the right ball park, so we've ruled it out as a major cause. Just something easy for you to check and soemthing that could be very wrong in kit cars.

I still reckon it's a brake balance issue. But that's only a guess as it's a bit hard to diagnose this here.

You definitely need a brake specialist. Brakes are something we all need to get right. Let us know how you go.

P.S. Plus I wanted to see if you could contort yourself enough to get in and measure the ratio. I was lucky and had the seats out at least.

stephen low · #8 (**permalink**) 11-11-2007, 02:04 PM

You Bast... Craig, my seat was in but not my steering wheel or shroud, it was still hard to measure!

400TT · #9 (**permalink**) 11-11-2007, 03:20 PM

Your steering wheel was out.

Bugger, my (16") steering wheel was in and it certainly caused me all sorts of problems.

Looks like my plan might have backfired.

stephen low · #10 (**permalink**) 11-15-2007, 03:56 PM

Chased my engineer as to whether he has seen my VIN yet but no luck. Seems Vicroads must be going into Xmas mode early, damn bureaucrats.

But good news is that the process of making the VIN application locks my car into the system for compliance, presumably as of the date of the application or its entry into the system.

Also took the opportunity to re-question the engineer on the brakes and it is the balance he is suggesting as needing tweaking as the best way to reduce the early front wheel lock up tendancy.

Presumably there are simple brake balance systems out there that can be fitting into the system? Can anyone point me at a picture of something applicable?

Is it a case of just re-routing all brake line outlets on the master through the proportioning system and thence to each corner? Then playing on road to get a suitable balance?

Any information would be great.

Cheers

Aussie Mike · #11 (**permalink**) 11-15-2007, 04:47 PM

My VIN seemed to take an eternity to arrive. I think I waited nearly 4 weeks. Hang in there, you'll be registered before you know it.

Cheers

400TT · #12 (**permalink**) 11-15-2007, 05:07 PM

Sounds like you are going to have to be patient for that VIN. QLD is no different, it's months for QT to approve.

Stephen, you will have to modify/disable the internal proportioning valve in that master cylinder of yours, then fit an in-line manual adjustable proportioning unit. Speak to a brake master cylinder reconditioning place, they will know what to do and what's the best approach with your master cylinder. They might also be able to correct the brake balance by swapping you to a different master cylinder.

Or alternatively you can fit better front calipers that have smaller piston capacity, that will also fix your brake balance and improve front braking. Nissan Skyline calipers should perfect piston size for you, but you will need to make sure you can mount/adapt them. The location of the mounting tangs on the calipers could make them anywhere from easy to difficult to mount.

Your pedal ratio is right, so you should be able to get great feeling brakes.

stephen low · #13 (**permalink**) 11-15-2007, 06:07 PM

Thanks guys.

Seems I might need to get another play permit for a short stint. I reckon vicroads won't be any better or worse than other Govt departments so I'll just have to wait!

Will talk the brake place I used to supply, recondition and repair some of my gear to get further advice. Fellow seems quite switched on and may have a solution.

Cheers