Stiffening the framework Options

[Rand]

I'm looking into ideas to strengthen my car. Not a full cage, just a few tubes. I've read the classic threads and I'm in awe of the caliber of guys (like Brad, Jeroen, etc) we have offering help around here... hoping for your comments on this...

My goal is an aggressive street car that is strong enough for a V8 conversion. I'm looking for the simplest way to add some strength (with the least amount of added pieces). It's all about function and I don't need to be concerned with racing classifications and rules.

I'm thinking the first stage is bracing from the rear shock tower to firewall, then inside firewall to frame rail, something like the red bars in this image:

(IMG:http://www.4nets.com/baldwinpowersports/images/stronger1.gif)

Is the firewall a strong enough part of the structure to use this way (if the tubes are just welded to their respective side of the firewall)? Or should the tubes go through the firewall, welded directly to each other at the top, and another down tube tied in (like the green)?

[riverman]

QUOTE (Brad Roberts @ Mar 11 2005, 09:48 PM)

QUOTE that fit over the outside longitudinals and up to the rear suspension mounts Correct... but... the issue in our cars.. when you increase the weight (V8 or 6cyl) and you increase rear spring pressure to make up for it... the chassis starts to split just in front of the shock towers... Brads kit doesnt address this and neither does the GT stiff kits. His tube placement will help distribute this load IF he picks up the front of the shock tower. Brads kit is super thick and super strong (no question).. but it attaches to the frame rail COVER not the frame rail. Our frame rails are strong/have strength on the inside of the car... not the outside. B

When you say the car will split in front of the shock towers, are you refering to the suspension riser breaking? Is this because the Mayeur kit doesn't extend beyond the suspension mounts and a weak area is left between the suspension mounts and the shock towers?

If this is the case, should I reinforce the area between the suspension mount and shock tower? Also, would it be advisable to stiffen the lower firewall (much like the Engman kit) and tie it in to the Mayeur kit to counteract twisting?

Also, when you talk about a car splitting, are you refering to race cars or street cars?