i just picked up a 93 f150 with the inline 6 and 5spd manual. unfortunately i dont have an oweners manual and jsut finished installing my tach. and i cant find any information on this engine such as where it redlines or anyhting like that any help is appreciated

 

For some reason, the Ford people didn't see a need to put a redline on the factory tachometer for the 4.9 either. When I first bought my '88, I had the same concern. At the time it had 110,000 miles. This was my first vehicle and I beat the hell out of it. And now the same truck with the original engine has 220,000 miles on it and I still don't know what the redline is. However, as I'm sure you noticed, the engine really has no power beyond 3,500 RPM. It's pretty much impossible to over rev the thing. The bottom end on most factory gasoline engines is good to at least 5,000 RPM before redline and probably a bit beyond that before you have to worry about causing a problem. However, given the power curve, there is really no excuse to ever rev the big 6 past 4,000. I think that the Ford people knew this and therefore never saw a need to add a redline. I'm reasonably certain that the engine will not rev high enough on its own to do any damage unless the operator decides to make an intentional effort to grenade the thing. So, my suggestion is to just drive in a manner that feels comfortable and don't worry about the redline. You'll have a hard time breaking something even if you try.

 

Yea. I have a 1982 f-250 4x4 with a strait 6. I doesn't matter what you do, if you keep oil in it it won't give up. Mine has 140,000 original miles, and power to let. I have a 4 speed so my gears are pretty low but it runs great. As for rpms you don't need it over 4,000. All it does after 4,000 is sound louder.

 

I am guessing that the OEM tach did not have a redline because they used the same tach for all 4 gas engines.

With that said, I'm almost certain that I read in a Chilton's manual that the redline is around 4250 RPM. For most practical purposes there is no need to rev this engine above 3000. Stay below 2000 if you want to see decent gas milage.

 

what about changing the cam?? when i do my rebuild i'm going to run a clifford cam, either the 264 or 272 duration, the low range rv/towing cam and the low to mid range cam respectively. which would be the better performer. mine is 4wd with aod.

 

Why are you rebuilding????

 

I would go with the low range, because of your engine selection

 

motor is at 190k, still runs strong so it's not something i'm going to do anytime soon, unless it dies on me before hand i'll probably go through it next year and freshen it up. haven't decided whether to just go with rings, gaskets and seals, or go all out and have completely machined. depends what i find whenever i do tear into it.

 

Don't ever tear it down and do everything but having it bored. Have the block and the heads machined. You won't get all the power back if you dont machine it.

 

i'll probably go all out on it. got a machine shop here that i've always used and doesn't charge me much. i've never tore one down and just threw rings in it. a lot of what i end up doing is going to be based on my budget at the time. i'd like to bore it, and go with the clifford rebuild kit and put a header on it. i asked about the cam because i was going to go with the rv one, then thought maybe the low to mid range would be better for running the interstate. i doubt i'll ever do much towing with this truck.

 

ok good yea i wont run it much over 3500 anyways cus it doesn't sound that great after that point. i bought the truck with 152600 on it and plan to keep it for a while too