I have a 90 f150 with the 5.0l and I am looking at freashing it up this spring. I have read here that the comp cams 31-255-5 is a good step up from stock. I will replace the lifters with, I think, the comps high energy hydraulic 832-16? I am wondering if I need to replace the valve springs and pushrods too? Also looking at upgrading to some roller tip rockers. Right now I am on a hunt for some explorer gt40 heads and intake but I haven't done the maf conversion so will the under intake work or can I replace it with the one that is for the sd on the truck. Do the 5.0l benefit from a high volume oil pump or is a stock replacement ok. Lastly I am looking at replacing the fuel injectors they ones in it are original but I think a freash set couldn't hurt. Can you step up the fuel injectors with out any computer or maf upgrade or is a freash set of 19#'ers ok. The truck runs good I just want to do it all at once.

 

You can't get too carried away with the older SD EFI setup, a cam and exhaust upgrade may stretch the limits in terms of drivability, you may find it has "issues" with idle quality if you throw too much at it.
If your motor has a lot of miles on it and is suffering oil pressure problems then it's time for a rebuild, a high vol oil pump is only a bandaid and may not totally cure the problem, and it's not needed at all on a healthy motor.

 

I figured that a high volume oil pump wasn't needed. I would like to do a Maf conversion but I am iffy about the repinning of the harness, and the ones you can buy are expensive. Are stock replacement injector ok? And I did forget to mention the plan for a set of header and and a go exhaust. Is in the near future. But I didn't know if a cam would be a wise upgrade. Or what was needed with it, if I should do it. I did read on here on the fsb website that the motor would benefit from a decent coil and cap and rotor, I did install quality plugs but the wires are just 8mm auto zones. I don't want to get crazy just better.

 

If you're going to buy new rockers, go for a set of full rollers. There's no gain to speak of with roller tipped only rockers. For a few dollars more you can get full rollers and the benefit the roller trunion offers over the sled fulcrums. As for the injectors, pull your spark plugs and see what they look like. That'll give you an idea as to whether or not they even need changing. They may just need a good cleaning.

 

Just saw that it was a 1990 engine, so it needed the pedestal mount. The lowest cost version is this:

Crane Energizer Pedestal Mount Roller Rocker Arms 44746-16 - SummitRacing.com

Otherwise, they just have a stock replacement:

COMP Cams High Energy Rocker Arms 1235-16 - SummitRacing.com

 

The 44746-16 are the reincarnated Cobra roller rockers used on the 93-95 Cobra 5.0. Good stuff.

 

With the Fuel Injectors I wouldn't go higher or maybe just a bit.

Accel offers 19lbs and 21lbs which can be used without ECU or Engine modifications

ACCEL Fuel Injectors 150819 - SummitRacing.com
ACCEL Fuel Injectors 150821 - SummitRacing.com

Quote: These injectors also utilize a new low-mass disc design that ensures a spray pattern for ultra-fine atomization and improved burn efficiency

Well, it "improved burn effiency" sounds good - like more power, less fuel consumption.

But first i would try it with cleaning the current Injectors.
Get a little ultrasonic cleaner and put them in.
Instead of using special ultrasonic clensing fluid, you can add just some dish soap and be astonished what comes out of the injectors.

And don't forget to change the fuel filter - that's one part people like to forget about.

 

You can use any type of 19lb injector on a 5.0/5.8 SD truck but nothing else, the computer is programmed around 19s, has no way to compensate for another size injector and in most cases isn't easily reprogrammed.

 

Really?
I thought the engine would run rich while heating up, than the oxygen sensor would tell the ECU to shorten the injection time.

 

But all the computer calculations are based on the injectors flowing at a 19lb/hr rate and if they don't then the computer will never get it right. These old computers don't have much adjustment range either so they can only compensate so much, and besides that 19lb injectors will support 300hp so there's really no need for anything else.