My 1991 f150 302 has 356k Km i was wondering if its worth putting header exaust maifolds on? plz give me some tips to improve horsepower..( just little things i can do to the outside of motor)

 

Shorties are by far the easiest but you'll nead to gut the cats or install a high flow version to get any benefit from them. You could also bump the timing a couple degrees for more power.

 

is there a timing tutorial in the FAQ section?

 

Summit racing sells a really easy set of headers for a good price (my big block kit was under $300, the 5.0L kit should be cheaper), They are Headman 'mid length' headers, it came with the headers, hardware, gaskets, a Y'pipe (with the o2 sensor bung) and enogh pipe to clear the transmission crossmember. When I bolted them on I noticed the difference in pulling hills and whatnot, I also just put on a MSD Blaster Coil that made it idle smoother and it does reek of raw fuel every time I start it up. And mine has 122,222.2 Miles (196,697 km)on it as of today.