I'm looking at upgrading the power in my '70 383 Barracuda, at what level of power should I fit the factory style torque boxes (front & rear) & at what level of power should I upgrade to frame connectors & what type should I fit?

I would rather fit the torque boxes first as they look factory stock.

Are any of the bolt in frame connectors worth fitting as it would be way easier to get the car back to stock if I didn't have to remove welded units.

The car is a street car that is not daily driven but can be, goes to the track 5(ish) times a year, looking at going to maybe 600-650 HP Hemi (auto).

Frame connectors will make a /6 car feel tighter. At 600-650 HP, I'd say they are a necessity to prevent excessive flexing of the unibody at the track. The bolt in type aren't near as effective as weld in. Torque boxes help a lot also - especially in the turns - but frame connectors are more important for straight line work.

Well, the factory used the torque boxes with the factory engine ratings so I agree on adding them first...Don't forget the rear torque box is there to keep from ripping the front spring mount out of place on the launch.....The US cartool type frame connectors are out if you're concerned about taking it back to original some day...That leaves only the styles like the MP bolt-on units that can be added{bolt or welded}without hacking/welding the floorpans...

Cheers for that.

Even if I don't go to the Hemi I will be upgrading my power so I'll go with the factory style torque boxes for a start & think about the frame connectors some more.

As my car is not a 1 of 3 car, being able to take it back to factory stock is probably less important that damaging the body due to lack of strength in the body/frame.

I will be working on these upgrades to my Cuda as well in the near future. I ordered my boxes <a href="from http://sheetmetalstuff.com/" target="_blank">fromhttp://sheetmetalstuff.com/</a> they are thicker and tiq welded. I got my frame connectors from http://www.magnumforceracing.com/store/d...arch=&Page= They can be bolted or welded in, I plan to do both (bolt them in first and then weld them. I plan on putting the frame conectors in first and then the boxes.