Strengthening 240z body for more power.....

[dat240z]

Hi fellas, just after some advice. Im in the final stage (spraying) of the RB 240z project. Its all been rubbed back to bear metal and getting ready to lay down the paint. Im wondering if I should do a half cage? strengthen chassis? etc? Ive noticed the factory led welds near rear hatch have started cracking since ive gone RB power. Would a rear strut brace assist? Im not going for a massive amount of power - aiming for 250-300rwkw, currently at 201.kw (stock rb25 + cooler + 3" exh)..

 

Any advice or suggestions would be greatly apprectiated.... Regards in advance

[RLY240]

My rally 240 has the cage welded from front towers to the  A pillars and rear towers and the lead seams still crack.

Roger

[dat2kman]

Overlay the chassis rails from behind engine cross member to the back of rail, bit of 1.2 mm bent in a U shape, and stitch weld, ie 1" weld, 1" no weld etc.

Pull guards off and on outer inner guard run some 1.2 mm sheet bracing bent at 90 deg from firewall to inner guard.

Do same on inside, ie below brake masters, and next to/below battery tray.

 

Leave rails in front of engine crossmember as is, you need some crush in a frontal impact.

 

This is usual rally car stuff.

 

Also stitch weld all seams in engine bay around towers.

[PeterAllen]

It's a big job but you might consider removing the sills and welding a tube brace from the 'A' pillar to the 'B' pillar, as per the yellow markings, then reattach the sills.

 

As I fitted wider sills I was able to install two tubes each side which also act as intrusion bars.

[RB30X]

Looks good.

 

How much extra are you anticipating this car will weigh once finished. The RTA will let you put the new LS7 in by the end.

[dat240z]

Thanks for the tips fellas, all look like good options. The lead welds have been redone, a rear strut brace custom made to suit AZC weld in camber plates. I guess Ill explore what avenue to go down, not sure of a half cage purely due the aesthetics.. Love them, but not style of this 240z.

 

Regarding weight, the engineers report came in at 1110kg, about 70kg more than with the L28 and factory running gear.  I also used two packs of dynamat+4L brush on bitumen tar+underbody rust protection....