Auto Racing: Me Again, comp cams, cam motor

Question
Hey Steve, this is Ben again.  A couple weeks ago, I asked you about getting 350 hp out of a 95 F150 and you told me about the gt40 heads and the other stuff.  You said a small cam would spice the heads up.  What brand do you recommend and what size does it need to be.  Oh yeah, and where did you say to get those heads at?  Another thing, about the exhaust,  I asked another guy on here and he said headers with 3" collectors and 2 1/2" pipe into an X-pipe straight into turn downs.  I want it sound like thunder coming down the road like a souped up mustang's exhaust.  I wanted to use 3" but he said use 2 1/2".  Does it matter.  Does that setup sound right for the sound I'm looking for?  Thanks Again, Steve
                                   -Ben

Answer
Ben-

  The cam size will depend on what kind of performance you want from your truck.  Different cams can result in very different engine characteristics.  For a heavy truck like an F-150, I'd recommend something mild that emphasizes low-mid rpm power.  Now...my knowledge of trucks isn't as good as it used to be, but I believe they came with regular 302s instead of 302HOs (also known as 5.0Ls).  This is important in cam selection because the 302 came has a smaller cam base circle than the 5.0Ls.  The 5.0Ls share their base circle with 351s while 302s share it with 289s.  I would contact Comp Cams help service (which I believe is www.camhelp.com) for an exact match...especially if the cam is a roller cam (again...my knowledge of non-Lightning trucks isn't what it used to be).  As far as measurements go, I'd look for something out of Comp Cams' Xtreme Energy line.  The best one I can see for all-around performance is part# 31-234-3...although that's a flat tappet cam and you may have a roller cam motor.  The cam measurements are as follows: duration...212int/218exh (both @ .050"), lift... .477"int/.484"exh, lobe seperation angle...110 degrees.  That may sound confusing, but it translates into very good low-mid range power and a good idle (but it will have a slightly meaner sound).  Something in that area should suit your perfectly.  As for the exhaust...I would never run straight pipes.  It would sound like crap and actually hurt power.  I would run regular shorty headers into 2 1/2" pipes into a good set of mufflers.  If you've got some cash lying around, Bassanni makes an amazing-sounding muffler...it just costs a lot at something like $200 per muffler.  Other good ones are Dynomax Super Turbos and Borlas.  I've heard good things about MAC mufflers as well as Edelbrocks.  Basically...just don't use Flowmasters or glasspacks and you'll be fine.  Oh...and the heads.  GT-40P heads are available from Central Coast Mustang along with the special headers you'll need for them.  Regular iron GT-40 heads can be had relatively cheap as well from a number of sources.  Hope this helps.

Steve