Decided to actually post something here finally after lurking the threads ever since I got my truck way back when because I can't seem to find all the information for parts I really need. I've been youtube/google/forum surfing for some time now and finally hit f-it and asking for help.
I have a 1991 f250 with a ZF5-S42 manual and a newish remand longblock put in roughly 35kish miles/10years ago and I've been wanting to do some performance upgrades to it pretty much ever since I've "restored" this truck to it's non leaking and non clunky sounding former self. About 2 years ago I had what I THOUGHT was a lower intake leak "turned out to be rear main that has now been replaced" on the back side in one of the corners and I was pouring out oil so started working down to replace it and thought "I remember taking all this crap off before when changing the motor and struggling with it so I'm gonna not put it back on" and decided to do just that so I've already gone through with a few things like EGR delete and smog system delete following the doings of the lovely fella in this video by just installing an egr plug and blockoff plate, shorter serp belt, installed shorty tube headers without any egr or smog system ports, put 75ohm resistors in the egr/tab/tad solenoid connectors, capped all of the no longer used vacuum ports coming off the vacuum tree and the other behind the throttle body and removed all the now useless junk.

I've driven the truck a lot more since that I've done that work and even now even more pushed to wanting to upgrade it performance wise and be a somewhat occasionally daily driver when the weather outside isn't motorcycle friendly. I've already come to the conclusion that I want/need to change the heads to GT40 heads and trying to source those now and I know that I'll need to upgrade the lower to compensate for the larger port sizes and still tossed between just porting/polishing myself or going with something like the edlebrock performer 3881 upper/lower intake manifold or if anyone knows where to buy a kit thats similar to the Edelbrock total power package SBF top end kit 2092 that comes with a upper/lower that my stock TB can mount to that would be great. I'm wanting to install a cam of which I have no idea on what cam to go with but still searching that one and thinking I need to upgrade the injectors as well to compensate for the now much better airflow this motor is getting but have no idea on the size of injectors to go with or how much the stock fuel pumps can support both pumps have been replaced with new oe/stock pumps but no clue of what the flow is of them but around 25-30gph from what I can find from some google searches. I'm also on the fence on if I would need to do any type of conversion to accept a MAF and ditch the factory MAP to allow for better tuning and honestly can't find crap about it anywhere.

I'm wanting to achieve the most HP I can without rebuilding lower end and without taking out a 2nd mortgage and offering the blood of my first born son. if someone has basically a list of "use these parts" or can suggest a few different options that would be amazing
I am a mechanic by trade so installing parts and whatnot would not be an issue but tuning wise is something I have zero experience in but am extremely tech savvy as well as being mechanically inclined as long as there's a tutorial or instructions on how to install said tune or how to tune it then I imagine I would be just fine

 

You will need a tunable EFI computer to do all that and the best option these days is a Pimpx from Stinger Performance because it will plug right into the factory wiring harness on your truck. With that you can then select any combo of topend parts you like as this system has none of the limitations that the OEM computer does.

 

Unless the GT40s just fall in your lap, you don't mind penny pinching & are skilled... buy aluminum, practically anything.

Here's your keys to tuning. You're ahead of the game having a manual:

https://www.stinger-performance.com/

And their version of this truck board, I think it opens to non-registered:

https://stinger-performance.proboards.com/

Here's my build history with budget heads & intake:

https://www.ford-trucks.com/forums/1...l#post16937337

 

Ok, I'll bite- what cheap aluminum heads are working these days?
There are bare heads on ePay for $250...

t
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BTFOM. Seriously. Last I looked at summit there were $900-1200 pair stuff complete, adjustable.

It comes & goes new & used, just a matter of shopping everywhere. Prices are all over the place since covid.

You used to get pedestal heads all over, not anymore. 2K+ if they have them.

 

I pointed out the only three aluminum, pedestal mount ones I know of that were or are made. Edelbrock, AFR, and FMS' GT40X.

Only downside to the X is they have an old style chamber (at least the pair I saw) The others have a heart/fast burn style...makes more power with less timing.

 

Point I'm trying to make is, 1) anything is better than stock & 2) if you're cheap or poor, but skilled GT40s are OK if easily came by.

But I wouldn't hang my build on scoring a pair + the cost to rehab them.

 

I am with you 100%. I have recommended budget aluminum heads forever. GT40 irons should have been 87+ heads on all SBF.

Many moons ago I had a set of OG three bar GT40 irons. Picked up cheap, someone wanted bad so I sent them. Makes sense...guide work not free. Springs. Seals. Etc. One would nearly have same cost into them as a nice set of aluminum.

 

I am a simple person- 3 letter acronyms, ok. 4 letters, sometimes. If Ford. 5 letters, my eyes cross.

so, buy cheap aluminum head. Any cheap aluminum head. Or not just any cheap aluminum head, only the right one?

t
the urban dictionary was... unhelpful... on this one.

t

 

AFR in relation to cylinder heads discussion= Air Flow Research. FMS, Ford Motor Sports, model GT40X, aluminum version of a GT40 with improvements available used only I think.

I'd take any AFR head, new/used, pedestal (I have a set of Cobra rockers) or adjustable 165cc runner & up if the price is right.

 

Ah- thanks,

t

 

All those heads are an improvement from the stock E7's.. see the chart below. A word of caution on the super cheap far east head castings that are everywhere, it's entirely possible the machine work will leave something to be desired and I have seen it mentioned that some valves may not seal perfectly, so these heads often need a little attention before they are bolted on.

 

If you buy aluminum make sure they are in stock, took me 3 years to get my Edelbrock, life goes on and my engine sits on the stand.