GTA replica - Page 7

PSk · #91 (**permalink**) 04-29-2007, 09:51 PM

Quote:

Originally Posted by Clayton105

For a given force, making the pad larger or smaller changes the “pressure” of the pad onto the disc. Pressure (Pascals) = Force (N) / Area (m^2). As you can see with this formula, the larger the area, the lower the “pressure” (not Force) applied to the disc. Compare eggs with eggs… Force and pressure are not the same thing. Do not get your units mixed up.

AndrewO · #92 (**permalink**) 04-30-2007, 05:07 PM

Clayton,

Yes we do fundamentally agree.

I said a small pad will be as effective as a large pad and the way to increase the force on the pad is to increase the size of the pots, not of the pads.

However I did say (or imply) it would be a mistake to ignore all of the system and just treat one part in isolation because they all affect each other (small pads create more heat), so to improve the braking of a system a larger pad (that as I said distributes the force of the pots across the disk) will decrease both fade and wear and thereby improve braking performance in the real world (more on the track than on the road).

The question was about real world applications, not about theory and formulas. PSK has a very simple and effective way to improve the braking without touching the brakes at all by cleverly looking at the entire system and improving the limitations. That's a great engineering solution to a real world problem without any formulas or confusion over units.

It was my mistake because I over reacted to your opening line of.....
"From a purely engineering viewpoint looking at a brake itself in isolation, the amount of torque a brake can exert on a wheel is totally independant of the contact surface area"

This can be interpreted (outside the engineering classroom and when considering brakes as a whole on an internet forum) as to say that the braking is independent of the pad area, which we agree is not true. I replied to confirm that pad area does have an impact on performance. Sorry if I went too far.

**davbert** · #93 (**permalink**) 04-30-2007, 06:41 PM

Quote:

Originally Posted by hagen111

Berlinesta's car has come back from the paintshop...

His project-topic on the dutch bulletin board.

**hagen111** · #94 (**permalink**) 05-01-2007, 04:16 AM

Quote:

Originally Posted by davbert

thanks for the great link to berlinestas car

i like what he's done with the rear sway bar... it looks like an adjustable blade type. I wonder if its adjustable from the cockpit?

ive been thinking of doing one for my gtv. anyone know if mounting the end links to the middle of the trailing arm with hamper its ability to twist radially?

cheers

d

PSk · #95 (**permalink**) 05-01-2007, 04:41 PM

Quote:

Originally Posted by hagen111

Berlinesta's car won't have a rear sway bar. The discussion (in dutch) was around running a sway bar on the rear or not. The actual pic is of the Alfaholics race car - and can be found on their website.

Berlinesta's car will be more 'old school' which I like a lot ...

**davbert** · #96 (**permalink**) 05-01-2007, 04:45 PM

hagen

thank you for clarifying

so this is the alfaholics car?

**davbert** · #97 (**permalink**) 05-01-2007, 04:55 PM

pete,

it would be a nice option to have something adjustable on the track to compensate for variance in handling for long stints.

seem like you may be able to build a much lighter rear bar if its mounted from below because of the shorter leverage.

but keeping simple and just dealing with the front end isnt a bad idea either.

just keeping up with " buying what u want rather than what u need" syndrome

cheers

d

**hagen111** · #98 (**permalink**) 05-02-2007, 06:56 AM

@Davbert; Yes I am pretty sure that is the Alfaholics racecar.

Here's a photo of an original GTA incl. rear sway bar.

More nice photo's on this site

Now, what I would love to see is Alfaholics produce an adjustable blade type front sway bar - so you can actually tune the balance of your car without the need of installing a rear sway bar.

Max Banks · #99 (**permalink**) 05-02-2007, 07:44 AM

Yes thats a shot of my race car last year. We mount our rear sway bar under the front of the trailing arms (in a similar fashion to Alfa GTAs) so that it is kept away from aftermarket rear axle linkages such as watts links and mumfords - fitting a rear mounted bar with them is quite a headache (but yes more efficient in terms of ratios). Rear sway bars are only required when using modified rear rollcentre linkages - the standard t-bar never generates enough roll to require one. Also a rear bar, in our experience, is only ever required with full slicks, anything less than full slicks cannot generate the cornering forces to warrant the rear bar. So your man is spot on if he does not use both of the above.

Max Banks · #**100** (**permalink**) 05-02-2007, 07:47 AM

We have played around with different diameter front rollbars and only ever come back to 1 bar - even in the wet on a full race car we are faster with a 29mm bar than a 27mm or 24mm due to increased stability - for this reason the blade front bar is not top of my priority list for new products.... but not to say that I won't ever make one - if I do, it will be cockpit adjustable.... for added tricks!

Veep · #**101** (**permalink**) 05-02-2007, 01:17 PM

Max, a little off-topic.. In the report on your trackday (was a lot of fun it seems...) you mentioned an ex-dutch trofeo race car that was present. Which car is it?? (color, former owner if known..).

Since I once started the Trofeo ,raced in the standard-series and organised it for some years together with some friends I am just a bit curious...