Chassis Strengthening RA28?

[jeffro ra28]

awesomeness, take a look at that link for some nice ra28 chassis strengthening!

+ rep

[GT1978]

Another of my favourites you should check out is Jaffa's TA22 project. TA22 GTR (4wd) 1uzfe Turbo Conversion
Yet to be completed but a seriouly insane proposal.

Glen

[MWP]

Im not convinced by his method.
He replaced a section of the standard chassis rail and linked up the rear.
Not much different than just inserting a section to join the front and back at the passenger foot well like i did, and Joel was thinking about.

[jeffro ra28]

Im not convinced by his method.
He replaced a section of the standard chassis rail and linked up the rear.
Not much different than just inserting a section to join the front and back at the passenger foot well like i did, and Joel was thinking about.

It looks nice tho Its a tidy looking job.

[GT1978]

He also flattened out the floor to give more room for his exhaust. This left a straight run front to back on the underside for the chassis rail.

[TurboRA28]

Just by joining the rails, would this make a big difference to the rear most section of the car where i'm finding the flex? I thought i'd need some extra bracing around the end of the rails, or some trianglular brace in the boot between the rear quarters and floor maybe?

[airfireman1]

Have you got or thought of a rear strut brace between the rear shock towers?
Cheers

[TurboRA28]

The cage attaches to rear arches as a cross bar between them.. so that area is probably ok.

[MWP]

I cant see how just running larger rails will stop twist.
The twisting action is down the center of the car, so you need some cross bracing from one side to the other (or similar, like a full cage) to stop the twist.

I know what i did isnt ideal either, but i think strengthening the sills, then linking the sills to the chassis rails, and using a larger gbox xmember (yet to be done) will help a decent amount.

Photos...


Welded angle down the length of the sills and joined to chassis rails with RHS.

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[allencr]

Is the rollbar and/or cage install going to have any conflicts?
If it's prefab or not, some of this stuff might be in the way of something else that should have priority.

[WDE_BDY]

Have you got or thought of a rear strut brace between the rear shock towers?
Cheers

I haven't seen many live axle cars that actually flex in that area, unless you have gone to coilovers. Even then a rear strut brace will do bugger all in most cases.

Callum

[barned01]

MWP, i can't see by that last picture (or my eyes can't interpret the angles of it correctly) but how have you butted the angle iron against the sill, is it that the flat end joins perpendicular to the sill edge or the flat part butts up against it?

what thickness rhs is everyone using? 2mm? 3mm? or even bigger?

[MWP]

I haven't seen many live axle cars that actually flex in that area

... and even less in a RS23/28 as there is a lot of box chassis back there already.

MWP, i can't see by that last picture (or my eyes can't interpret the angles of it correctly) but how have you butted the angle iron against the sill, is it that the flat end joins perpendicular to the sill edge or the flat part butts up against it?
what thickness rhs is everyone using? 2mm? 3mm? or even bigger?

Errrm, im not sure what you mean by your question...
The angle was 2mm from memory, and the RHS was 3mm.

Another photo from a slightly different angle if it helps:

[TA22 1MZ]

where are you guys in Sydney getting your RHS from? Whats the price like for 2 & 3mm per metre? got a mate who can source some from his work, just want to know what rrp is and how good of a deal he can get me.

[jeffro ra28]

In Tamworth i just bought 6 meters of 50x50x3mm agsteel (between second and first grade) for $67 on special.
50x50x3mm 1st grade was around 30 a meter !

That is a bit big for this sort of car stuff but it might give you an idea tho.

I dare say that 25x25 would be half the price.