Corkys like breastplate

[nathanMR2]

Not cheap mate, looking at £150-£200 second hand. They are hard to come by also.

The original ones were made out of ali, a steel construction is said to be heavy and not ideal for this kind of application

[Paulm]

I'll have a look at the cost in Ali then

[nathanMR2]

Let us know how you get on

[ChrisGB]

If you are doing it in 6mm mild or stainless steel (or even in aluminium) you could get laser profiling done which would be great for getting the holes the right size and shape without needing to drill them afterwards.

You should see nice neat edges too.

Chris

[ad_car_08]

Last night, over a pint of the local brew, I was having a chat to my brother about making one of these breast plates, and he quizzed me about the actual gains of fitting one.
So many people have them fitted and say they're one of the best modifications to make, and they're in such rare supply....so many people can't be wrong?!
The points I'd put across;
- the original bracing is thin/flimsy in comparison
- the original bracing is made up of two parts, where as a corkeys style brace is 1 unit that should uphold chassis stiffness(?)

The points he put across;
- If there's any sort of flex, it would be more likely to be around the suspension strut areas, so surely more gains could be had from a strut brace? using a tower as an extremely basic example, if you secure the bottom, the top is still likely to wobble around, but if you secure the top, the bottom is less likely to move as much.

Our conversation has got me questioning which is the best route to go down now...breast plate or top mounted strut brace?
I read somewhere that an aftermarket strut brace would offer no performance gains, as the standard "X" bracing in the engine bay does a perfectly good job already, which would leave a strut brace in the frunk....but then would that really make much of a difference??  s:? :? s:?

[Mad Matt]

Your brother's right in respect to most cars (well in my limited experience). So, fitting a front strut brace on my Fiat Barchetta made a lot of difference.

As I understand it, on the MR2, we've already got quite a lot of bracing and being RWD the back end would generate most problems anyway. So the current bracing at the back appears to do a fairly good job. The front seems fairly sorted as well and isn't put under pressure by having power through the wheels. The weak point seems to be in the middle. When I say weak point, it's all a matter of perspective. The MR2 seemed to me to be one of the sweetest chassis I'd ever driven when I first got in it. So it's all a mater of degrees.....

Just an opinion.....

[markiii]

front strut brace is also an essentialmod,

which makes more difference corky or front strut? is all a matter of opiniion

[StuM]

I would argue that stiffening the front end with a strut brace actually enhance the need for the breastplate - the lateral flex will happen in the least stiff part.

[Anonymous]

I noticed the FSB far more than the breastplate, however that was also the first one to go on (both on my old car and on Jo's) so may have been a trick of the mind perhaps. That said, as Mark says I would consider them both to be must-haves, and really should be the first mod any one does to their car: The difference they make is like night and day.

[ad_car_08]

ah ha! Fantastic! Thank you for your replies/opinions   s:D s:D

[Mad Matt]

Does the degree of improvement and which is more helpful vary for the pre/post-facelift models?

[nathanMR2]

I couldnt comment really, but what i will say is that further bracing was added to the facelift model so there must be a suggestion something more was needed.

[Paulm]

Oakly dokely, looks like I could do them for £100 for the breastplatein 6082T6 6mm Ali, this would include the all holes and the angle bracing welded on , but with the webs cut out by plasma cutter via a template, still trying to find a local laser/water cutter bod, If a few of us can get together, then should be able to get them done for the same-ish price with them being laser cut

[Anonymous]

Oakly dokely, looks like I could do them for £100 for the breastplatein 6082T6 6mm Ali, this would include the all holes and the angle bracing welded on , but with the webs cut out by plasma cutter via a template, still trying to find a local laser/water cutter bod, If a few of us can get together, then should be able to get them done for the same-ish price with them being laser cut

Are you using that drawing I posted a few posts back? Do you want the geometry of the holes updated and a revised drawing posted? Remember that the geometry I show for the three pipe clip holes is not optimum....

[Paulm]

That it'd really useful thanks

[OlberJ]

Crikey Paul, talk about taking the bull by the horns!

You can count me in for a BP, lasercut or plasma cut.

[Anonymous]

That it'd really useful thanks

Any particular geometry, or just matching the Toyota hole geometry? Do you want the area where the holes are to show a skim down to the stock Toyota thickness so that the clamps just snap in as normal? How are you planning on it?

Once I know then I can do the updates.

[Paulm]

If you can just match the toyota hole geometry that'd be best, dont worry about the skim for the plate thickness, I'll get the father in law to locally mill around the clip holes so the material only thins out say inch radius around the clip holes and doesnt weaken the  plate.

[ChrisGB]

The points he put across;
- If there's any sort of flex, it would be more likely to be around the suspension strut areas, so surely more gains could be had from a strut brace? using a tower as an extremely basic example, if you secure the bottom, the top is still likely to wobble around, but if you secure the top, the bottom is less likely to move as much.

The breastplate needs some understanding to make sense. Essentially, the front and rear firewalls of the car support the strut towers at each end. These firewalls are joined by a panel that is essentially an inverted U channel with flaps of metal either side onto which the sills are welded. By putting the breastplate on, you turn the U channel into a tube. What this does is stabilise the centre section by not permitting one side of the floorpan to move relative to the other. The plate works almost exclusively to resist shear. This helps the car chassis resist twisting, so keeps the front and read better coupled and gives the suspension a more rigid platform to work off.

Chris

[ad_car_08]

ChrisGB, I can't thank you enough! That's exactly the description I was about to look for! I was going to ask but thought I'd probably get   s:flame: :flame: s:flame:   and told to search!!

[grsymons]

Oakly dokely, looks like I could do them for £100 for the breastplatein 6082T6 6mm Ali, this would include the all holes and the angle bracing welded on , but with the webs cut out by plasma cutter via a template, still trying to find a local laser/water cutter bod, If a few of us can get together, then should be able to get them done for the same-ish price with them being laser cut

Hey up paul, fancy seeing you over here   s:) s:)  

Count me in too.

[Paulm]

SShhhhh !  Wanna buy a tit plate guvnor

[Anonymous]

Drawing now updated; sorry for the delay - I have been rushed off my feet with damn work....

http://www.box.net/shared/0jzj10g4ej

[Paulm]

Superb work, I'll get it priced up this week

[Paulm]

Right finally got a couple of these machined up for trial, they've been done in 8mm Ali instead of 6mm and are pretty robust so may not need the angle welded on. I'll pick them up at the weekend and post a pic or two on a how it fits.