Another tech tip for keeping the RAT in RAT RODS:
As you know, I've been rebuilding my entire exhaust system from the heads back. If you consult any forum or body of experts, they will insist that you use "mandrel bent" tubing. Mandrel bent tubing is a constant diameter throughout the curvature of the tube. This makes it flow better as well as making it far easier to cut and weld sections together. Of course mandrel bent tubing is much more expensive and harder to obtain. You probably can't find it at AutoZone. However, if you don't use mandrel bent tubing, all the experts will turn up their noses at you.
Rat rods are works of art that break the rules. We build things cheap and we improvise. If street rodders are using mandrel bent, that's the LAST THING I want on my car. So when building my headers and exhaust I specifically chose CRUSH BENT tubing. I was able to get it quickly and inexpensively from a neighborhood muffler shop, but it's also available at most any auto parts store. But the problem is, I needed to make some compound curves in my system, linking multiple curves together. How can you do that when the curves of crush bent tubing are smashed into oblong shapes? In the pics below you can see how the crushes elongate the tube so the end don't align.
No problem: just cut the tube where you want it, then whack the tube end with a hammer on its tall side. This will force it back round again. Also do it to the tube end you are welding it to until both are the same shape and can now be welded together. The last two pics are of the sexy curve I made to match my tailpipe up to my stacks using this technique on crush bent tube.
