Maythej

I have a 5.8l f150. It has been bored .30 over and has a ford racing cam. It has headers. When it gets up to normal temp it stalls out if it's idling. Im wondering if I need to upgrade/tune the computer? If so how would I go about seth m doing so?

BLDTruth

The cam is probably the problem. What year is the truck, and is it a speed density truck or mass air flow truck? If you don't know the difference, look at the air intake - if it has a sensor right off of the airbox with an electrical connector, that is the mass air flow sensor. If no sensor there it is speed density. Speed density trucks cannot really be tuned and require a a healthy amount of vacuum at idle, which a ford racing cam may not be providing. Mass air flow trucks are a little easier to tune.

Generally speaking, you are going to have problems with a ford racing cam in a truck engine. They are usually designed for high rpm horsepower and not the low rpm torque that a truck needs.

Maythej

It has a map sensor. No maf. I looked up the specs on the cam it's for a truck for low end torque mostly. Do you think if I found a good stock cam it will run alright then?

BLDTruth

If the cam specs are good then I would go over the basics to make sure its not something simpler - verify base timing, measure fuel pressure, and pull codes. Make sure the EGR valve is functioning properly - that can cause all kinds of problems if not working properly when warmed up. You have a modified engine so its difficult to diagnose without knowing everything that has been done to it.

And vacuum lines - make sure they are all good, especially the ones to the MAP sensor and the fuel pressure regulator.

sdmartin65

Usually racing cams in truck or mustang can have a list of strange problems at idle or slow street driving. They just don't like to run good below 1000 rpm's, not much good for a street driven vehicle.