is there any way to test or when to know when they need to be replaced and ive heard when u go with a diffenet set other than stock that u need to get the computer reprogramed. also is there a "chip" they make for my truck that will give some more hp and where would it plug into thanks guys

 

I have Ford Racing injectors for an 87-93 5.0 Mustang in my truck. They are the stock 19# rate that are yellow/orange color. I got them from Summit for less than 200 bucks. I had a few that were bad and didn't want to test them try to find out which ones were bad and then replace them. This way they are all new and the job only had to be done once. The same injectors should work in your 5.8. I believe they are the exact same thing.

You only need to recalibrate the mass air meter if you go with larger injectors. There is no reason to go with larger injectors unless you have a massive amount of horsepower/torque such as upgraded heads and a blower. If yours is mostly stock, the bigger injectors won't gain your truck anything.