I'm running Doug's Headers "452" on my 493 in a 72 Cuda. Had to massage the header where it passed the steering column. These are 2" primarys forget ever being able to access the starter in car, I'm running a denso off of a dakota so its the small starter, still impossible to remove once in car. I drop the engine in with the starter already mounted, still takes a while to access wiring etc. I recently added power steering for my wifey, these headers are not designed to work with it and I put the steering box in with the engine in the car, otherwise I couldn't have done it. It touches the header and I had to massage it to fix that. I run jacobs spark plug wires with the ceramic boots after burning up several other brands, its the only ones I've found that will work without those nasty looking shields. The headers work great but I'm disappointed the ceramic coating started going away within a year. I can't say anything about the TTI's, but I do run the TTI exhaust system all the way back with the 3" pipe. That's a nice setup. I also run a cross pipe like came on the Hemi cars back in the day, whether it adds anything I don't know. The exhaust is so large I think any benefit it gave the hemi cars is lost. Hope this helps in your decision. [image][/image]