Could this be the timing chain (351W)?
 

Ever since I put an EFI 5.8 in my 93 it ran rough at low speed. This included a miss at idle and some bucking and hesitation. Fine at higher RPM. Never bothered me too much but now I'm headed to Europe w/the car so I want it perfect.

Someone on the board told me to replace the O2 sensors. Did that, the car is better, almost. Still have a little bit of the problem.

I believe the 5.8 was out of a truck (it now has GT-40 lower, cobra upper, 24 LB inj, 73 mm mass air, 70 m throttle b, adj press reg, bigger fuel pump). Someone told me that the timing chain may not be compatable w/my HO computer and that I should get an HO timing chain.

Something about ford wanting more torque out of the truck 5.8s so they changed the timing chain.
This sound reasonable?

I dont see how a cam could have anything to do with the computer. Its just there to connect the crank to the cam. There are different types of chains but they all do the EXACT same thing. The only possibility is if its getting worn then you would start to lose timing. But the type of chain doesnt affect the computer.

Kick who ever told you that in the nuts. The idea of the timing chain not being compatable in this case is ludicrus.

-Josh, aka the tireburner

Every time I have had a fuel injected 5.0 engine that doesn't run properly, it is because of an electrical problem. The windsor short block mechanicals are usually really stout (except for some of the older timing chains that have plastic coatings, but if this was bad, the engine would run horribly at all RPM and maybe not even run at all) I would get a scan tool possibly to see if you can find where the problem lies. Most likely an electrical/sensor problem.

Sounds more like a timing issue to me. What distributor do you have in it and what base timing advance?

I'll have to check on the timing. I know the distributor is a stock unit, off a truck I would presume. There is now way that a timing chain could cause a miss?

Nope.

I would check the plugs, rotor. wires and cap a miss is almost always ignition related.

OK, I guess you guys saved me from doing the chain for no reason. I'll look at the other stuff