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351W EFI (5.8L) mods ??


Well-Known Member
I'm getting a 95 F-150 with 5.8L motor and auto transmission. I'll be building a serious prerunner from the ground up, and will be rebuilding the motor myself. Has anyone here seriously built up the same motor and kept it smog legal? What did you do to it? I had a '92 Bronco with the same motor, so I'm familiar with the usual bolt on performance stuff for that motor.

This is what I'm planning on adding......Edelbrock aluminum heads, intake manifold, throttle body, and camshaft. MSD ignition, aftermarket headers, roller rocker arms and a aftermarket chip...etc etc.

Where's a good place in the South Bay that can machine/hone the block for me?
Recommend any specific pistons, bearings, etc etc ??

I'd like to get a Lighnting but from what I've heard, they didnt offer them in a ext. cab version.

Any help would be great.



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No on the lighting, but you can get the Harley Davidson edition in an ex-cab, The engine is the same but with a smaller pulley on the super charger. It can be changed easily.

Dale my son ran a 12.96 in his lighting with a few additions.


What is your budget on the motor? I've built a few 351w motors but they all had carbs. I've worked on a few 5.8's and know the following.... all the performance modifications like heads and intakes won't do POOP without new injectors and some better fuel delivery. When I was building my personal 351w motor for my Bronco project I elected to keep it simple and decided to ditch the smog stuff. It's mild mannered and makes a little over 400hp at the crank. With the 5.8 and SMOG laws you have to spend more to make more. Figure out what your budget is, what your performance goal is, and how reliable you want it to be. Dollar for dollar it's hard to beat a quality stroker kit.

Check out all of the hotrod and Mustang performance magazines - horsepower and torque figures are included in almost every article - I built my motor using parts tested in a HotRod article. They used the dyno to figure out what worked together and I built something similar. Before you drop money on aluminum heads and other trick stuff, make sure the computer and everything else will work together. Regarding the SMOG... as long as you keep it looking relatively stock there are plenty of ways to fool the sniffers. I've never had a problem with actual readings, it's always been the visual inspection I fail. Something as stupid as running 1 non CARB-EO labeled aftermarket part and they can fail you.

The older 5.8L Lightning motors weren't supercharged and still made respectable HP. According to Ford the 5.8L in the older Lightning made around 240hp. You can find these in junkyards every once and a while.



Well-Known Member
I've done all the mods you mention to the barge, heads, intake, cam, pistons, headers, throttle body, ignition, larger injectors, feul pump.... the list goes on. The problem is the stock computer. It will not run right even with small mods to the motor. An aftermarket chip is not going to work right unless you have someone burn one specificaly for your motor while running it on a dyno. I know of no one doing this for the ford speed density systems as of now. The only way to get mine to run worth a crap and idle was to go with an aftermarket EFI computer. I now have a fully programible set-up that plugs into the stock harness and runs like a dream. It's just not smog legal, Oh well! On the edelbrock headers take the paint of before installing them. The paint they use burns off in the first 5 min. and turns to dust not to mention your truck looking like it's on fire!


Well-Known Member
What year was your 5.8L Brian, because the '95 has a mass airflow sensor. It's not a speed density setup. I'm trying to build something very reliable and not too expensive. All the parts I'll be installing are smog legal. I'm also getting a larger mass airflow sensor that they can calibrate for bigger injectors if it needs it.


Well-Known Member
I think they switched in '94, because my '92 Bronco was speed density. I was gonna convert it to a mass air flow, but never ended up doing it.


Well-Known Member
You might be okay with the mass air set-up. They are alot more forgiving than the SD's. I don't have any experiance with the 5.8 ones, only the 5.0's. Don't know if there the same.
Hey im chris. Ive got an 89 bronco with a 351w efi. Was wondering if you guys knew if its possible for aluminum heads on an efi engine since every magazine ive looked at for parts says that aluminum heads arent an option for efi engines.. Help please. Lookin to make this beast fast already pretty quick but im sure there are a few things left i have to do to be complete with the engine.


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You just dug up a very old thread.

Aluminum heads will work with EFI engines. If you switch to a GT40 style head you will need a different lower manifold.

See http://www.nloc.net/ and http://www.gofastbroncos.com/ for lots of info. The first gen Lightning had a full roller EFI 351w with iron GT40 heads. The Lightning guys are the kings of making power with a 351 based motor.
Don't waste your time unless you plan on changing the EFI at the same time. 89's are speed density systems and don't respond well to performance changes. Any sort of cam will really mess them up. Swaping to mass air is about hte only way to get a decent running motor.
okay can someone give me suggestions. Im thinking of switching from efi to carb..? Convert to maf. After i do that would any upgrade pretty much respond well with the engine i want atleast 400hp out of it.
im reopening a really old thread, recently bought a 95 f150 5.8 efi xlt 4x4 i have added.... msd ignition coil, msd cap and rotor, ford racing plug wires, motorcraft copper sparkplugs, pacesetter shorty headers i have no idea about a cam and think i found gt40 heads on a 94 svt mustang not sure if theyll work.... im about to buy edelbrock intake manifold 3881( everything has come from summit racing) need tips on what cams to go with and a decent twin throttle body they suggested one but it doesnt show up my email is emharris1765@gmail.com if i dont get to get back on to read the thread right away appreciate it yall thanks