You beauty!.........through engineering

[stephen low]

G'day All

Seems the God's were kind to me today, well at least my engineer was, as I'm through engineering.

Have a couple of minor issues to sort plus I need to lower the seats some more, but I was planning on doing that anyway, so its wait for the VIN number now. Hoo-bloody-ray

One issue he passed me on but suggested some more work was the brakes. The brakes don't need a great deal of effort, relatively speaking, to achieve a lock up on the front. The suggestion was to set the system to require a bit more pedal pressure without getting to lock up stage as quickly.

Any advice on how I can achieve this? Am running S2 Jag brakes F and R and Sigma booster with Ford master.

Cheers

A very happy Slowy!!

[Philm]

Congratulations,

Almost there, can't help on the brakes issue.

Phil

[Rebel1]

Stephen, Investigate putting Nissan 4 spot alloy calipers on the front.

They are slightly smaller than the jag (maybe better balance) and are a whole lot lighter than the jag calipers. Still uses the Jag rotor.

May be other options.

Cheers

[NASSTY]

Is shortening the brake pedal an option? To invoke less leverage?

Are your tyres any good?

Congratualtions Slowy!!!
Almost there!!!!!

[400TT]

Well done mate.

The Nissan calipers will help rectify the front -> back brake balance. Are your calipers the 4 piston jag ones, I know they are the worst for brake balance in a cobra as they have very large pistons. 48mm pistons from memory. The Nissan calipers have smaller 37mm pistons. Assuming you pedal ratio is similiar to mine, I've calculated with standard jag rotor, that Nissan calipers will give close to perfect brake balance. If you have a larger rotor(like I have bought), then you will need something in between the jag and nissan piston sizes. You can get Wilwoods that are perfect, just slightly larger pistons than the Skyline calipers or 2 piston PBR calipers that have 42mm piston sizes from memory, getting a little on the large size, but still much better than jag 4 piston.

The jag 3 piston calipers have a much better piston size and will help brake balance.

Is your pedal travel feel about right?

I would fix the brake balance first, then see how it all feels.

You can sit down and calculate this stuff, lots of info on the Internet on it. Very time consuming though.

[LoBelly]

Fantastic Stuff Stephen

Congratulations on getting it through (and with two months to spare!)

Will we get to see it on Thursday?

LoBelly

[letsboogie351]

Congratulations
we all love to hear good news

cheers
Doug

[stephen low]

Thanks for the comments guys.

Tyres are new old ie 7yo but now first use so grip is fine as rubber is still good and calipers are the 4 spots I believe.

Set the actuation to come on fairly early in the pedal travel but that's just where the pedal is related to the booster shaft by the connecting yoke. I wouldn't have thought winding the yoke out some would change the pedal pressure, just when the brakes get actuated from the un-depressed pedal location.

Certainly not going to rush at this one pre-rego. but practically the idea of being able to stop over a shorter distance with less likelihood of lock up is all good in my mind.

Sounds like some more research to come. Will start this at the next club meeting next week but there won't be a car Michael, I'm still on my play permit which I am happy to push the testing boundary on, but explaining an after 7pm drive, to an orrifficer of the raw, would be most difficult.

Still waiting to see yours - you show me yours first!!!?!

Oh and I should say for those that don't know the history, semi rolling kit bought end Feb 06, with an engine choice necessitating rego this year and I aint a single bloke either. So there has been a lot of midnight oil burnt in the last 20 months!!

Cheers

[cameron02]

Well done Stephen.

re the brakes. You could always put some air into the system. That should make it much harder to lock up (I take no responsibility for any death injury or vehicle damage that may occur)

[400TT]

Originally Posted by cameron02

You could always put some air into the system. That should make it much harder to lock up (I take no responsibility for any death injury or vehicle damage that may occur)

Now that's thinking outside the square.

[macloft]

Well done How many beers to celebrate the birth.
Bruce

[Ross Smith]

Congratulations Slowy,

Regarding the brakes, do you know what proportioning valve is in the master cylinder? I think then original Sigma is 60/40, the brake specialists in Perth covert all Cobra/Sigma master cylinders to 50/50 to get a beter balance. That may solve your problem.

Cheers

Ross

[stephen low]

Ross

Thanks that might be just the tonic. I'll have a chat to a few people on that one.

I do recall asking the brake specialist I was getting bits from, and whom helped reco the master and replace the reservoir after I found it had self destructed, as to whether you could alter the inbuilt proportioning valve.

If I remember rightly the answer wasn't no, but it didn't sound like a necessarily easy fix. Worth a try though.

Now as to Cam2's suggestion, I think his thinking is off this planet or at least he is out of his tree, let alone the square!!

But logically, if I leave the system full of air, I'll get no lock ups at all - correct?

Problem solved - sorta!??!

[Plums]

Congrats Slowy!!!

On the brake issue, perhaps you could try changing the moment by moving the yoke attaching point down the pedal by a small amount... Perhaps?!?!

[Beejay]

Well done!

Ben

[stephen low]

Bobby

Your suggestion is much the same as Nasty's and it may have merit.

I'll need some professional advice on that.

This change would not be just a simple one to achieve the way my car is set out.

Thanks

[400TT]

Originally Posted by stephen low

Your suggestion is much the same as Nasty's and it may have merit.

That's the pedal ratio you are changing. Measure what your pedal ratio is and compare it to someone else with similiar brake setup. Should tell you whether you are in the ball park. I've got a similiar brake setup, so could measure my pedal ratio for you if you are interested.

[Rob. Smith]

YAY ! rego winner. The most satisfying result..I have an RMC which has a sigma booster,Ford master and jag brakes. My system was supposed to have two separate lines from the master to the front brakes. I blocked the front fitting,bottom one, off and ran a single line to a j-block that ran to each front brake. The pedal is very "production"
Thanks to my engineer and Norm Thoroughgood (brake magician) for this little mod.

[stephen low]

Craig

Am always interested whether it becomes useful or not - so measure on please.

Rob

Not quite rego yet, that's the next but easier step compared to passing the ADR's. Am most interested in what you have done. Can you do pics to help better describe as the RMC and GF are much the same in this respect.

If it is working for you it must be worth consideration as do-able, though the legality of a single feed to the front is dubious I believe.

Look forward to some pictures.

Cheers

[schipps]

Well done Stephen. Great effort. All of those hours are finally paying off and that light at the end of the tunnel is getting very close now...