>How much real world HP is a complete exhaust system worth? Headers, complete 3" mandrel bent system, etc... Any recommended brands?
I haven't had mine dynoed but there is a vast improvement with the headers. I run the BORLAS and they took about 6 hours for me to install. I also placed venturis at the collectors in the y-pipe to prevent the low end power loss. If you look under the truck the cat-back is really a very good exhaust set-up. I would recommend a new muffler over a complete new system. There have been several different ones used for this, I have a FLWOMASTER 40 series and guys say it sounds really nice.
>How do you get rid of the 97 mph governor? (his friend wanted to know)
Get a chip or a programmer (SCMT or PPIII) [img]/ubbthreads/images/graemlins/biggrin.gif[/img]. I run the PPIII and the dual fuel settings really make it versatile. They will allow you to set the gov a bit higher. PLEASE remember your truck will weigh over 6500-7000 lbs, at 97mph thats a lot of mass at high speed and metal will bend.
If you want the chip, do all other mods first. This would allow you to get a custom burned chip to help put all the mods to better use.
>Does anyone make a decent chip? I've heard most were fairly disappointing comparison to the results of "chipping" a diesel.
Several guys have both SUPERCHIP or DIABLO and report good results with both.
>Any easy HP mods? How much of a gain is there to be had putting a new intake/air cleaner system on it?
Is any of it that easy?? The PPIII was by far the easiest for me. I lost power with the larger wheels/tires. PPIII has returned that lost power with plenty of pedal to spare. I modded my intake, I cut down the snorkle end that runs into the front grill area. I put in a K&N filter and it works. I'm looking into a cheap intake set-up that replaces the main body hose that runs after the MAF and into the throttle body.
You could run and electric fan and COBRA water pump. Fans are not cheap ($300-$400)

and there are few applications for our trucks. [img]/ubbthreads/images/graemlins/confused.gif[/img]
I haven't dynoed my truck, but between the headers and PPIII that was the best money spent. [img]/ubbthreads/images/graemlins/cool.gif[/img]
Good luck