Stitch Welded Front Sub-Frame

[DRTDVL]

Has anyone contemplated doing this to stiffen up the front of the car?

I know on my 205 it made a decent difference to the car, but wasn't sure how stiff the fronts of the Z's are to start with. Has anyone added a lower front brace before?

 

[frankvdb]

Has anyone contemplated doing this to stiffen up the front of the car?

I know on my 205 it made a decent difference to the car, but wasn't sure how stiff the fronts of the Z's are to start with. Has anyone added a lower front brace before?

Pretty sure the THP200 already comes with an anti-roll bar underneath the engine so there should be a standard part and it should fit and make a difference!

 

[DRTDVL]

Yeah,

I want the car tighter and stiffer than that. Tempted by coilovers and a few other things, but still paying off a holiday and doing an EW engine conversion on my 205 racecar. So looking for cheaper mod's at the moment.

 

[Anonymous]

Wouldn't recommend stitch welding

The front axle is a MacPherson strut type with a drop link anti-roll bar. The sub frame is
attached at four points under the chassis legs and front floor. Each wishbone moves around
two flexible mountings rigidly attached to the sub-frame.

Stitch welding will most likely make the sub-frame too stiff and compromise handling rather than improve it

 

[stagger321]

Wouldn't recommend stitch welding

The front axle is a MacPherson strut type with a drop link anti-roll bar. The sub frame is
attached at four points under the chassis legs and front floor. Each wishbone moves around
two flexible mountings rigidly attached to the sub-frame.

Stitch welding will most likely make the sub-frame too stiff and compromise handling rather than improve it

I'd agree with this. Its one thing changing easily bolt on items like shocks, AR bars etc, its something else making perm changes to something like a subframe.

Don't know if the R has beefed up AR bar? Maybe that is an option if you can get hold of one.
Having said that the R has diff suspension geometry with diff camber and toe-in angles amongst others, so don't know how well R bolt-ons could be used on the rest of the range.

 

[DRTDVL]

Just curious about why you guys think that stiffening the subframe would comprise the handling?

I know with the 205 it made a lovely difference to the handling, and that reducing the flex / distortion of the subframe would reduce and resulting wheel geometry cause by movements in the control arm mounting locations.

 

[Anonymous]

the Subframe on the RCZ Is pretty stiff as it is. if you wanted a cheap modification the instead of welding the subframe which could have irreversible effects how about fabricating a new ARB based on the OEM?

A Thicker bar will make a good difference and will be cheap.

 

[stagger321]

Just curious about why you guys think that stiffening the subframe would comprise the handling?

I know with the 205 it made a lovely difference to the handling, and that reducing the flex / distortion of the subframe would reduce and resulting wheel geometry cause by movements in the control arm mounting locations.

The thing is nobody knows what the impact would be.
The RCZ is based of the 308, a much heavier, yet torsionally stiffer car than the relatively ancient standard spec 205. So the subframe as Figo says is going to be stiffer anyway.
Why risk it on something that is not that easy to undo.
I'd make the changes on bolt-on items first - but its your call.

 

[DRTDVL]

True. It is stiffer than the 205 I was just using it as an example.

Companies like ultra racing make chassis bracing for modern cars, problem with them is they drastically decrease the ground clearance because of their design.

Arb's and chassis bracing / stiffening are different.

Either way, I'm focussed on my other cars at the moment so I'll be looking into this later.