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Need help: motor options for 1976 build

betzgb

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Dec 22, 2009
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182
I am building up a 1976 and I need some help thinking through options for the motor. I have $1500-$2000 max as my motor budget. The truck will be a daily driver and I expect to drive about 10k miles a year. Torque is important because I will tow quite a bit and I would like to go to EFI route for reliability. It will be mated to a NV 3550 transmission with 4.3 inch gears and 33 inch tires. I also want to run air conditioning and not leak like crazy on my garage floor six months from now :)

I have collected some potential components to start with. I have a 302 that came out of the truck but I don’t know the history on it. It has a two barrel carburetor and runs well on the test stand and compression is OK. I don’t know the mileage on it and to my knowledge everything is stock and probably tired.

I also have a 5.0L motor from a 1996 Ford explorer with everything including the EFI set up, front dress, and accessories like the alternator, power steering pump, etc. it does have GT40 heads. Mileage is unknown as the speedometer stopped working at 163,000 miles several years ago. It was used as a hunting truck and not driven a whole lot in recent years.

Given these parts to start with and my budget how to build a reliable 300hp ish daily driver motor with good torque?
 

sykanr0ng

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Aug 11, 2014
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When you say towing how big and how heavy are you talking about?
A Bronco is not the choice for towing anything big or heavy.
 
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betzgb

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You are correct. Either a trailer with home-improvement projects like lumber concrete bags etc. Or a trailer with two seadoos
 

sanndmann3

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Jun 13, 2007
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1,774
I'd do a similar compression check on the Explorer motor for comparison. I'd bet the fuel injected motor is in better shape and would be tempted to use that...
 

sykanr0ng

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Aug 11, 2014
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I'd do a similar compression check on the Explorer motor for comparison. I'd bet the fuel injected motor is in better shape and would be tempted to use that...

/\/\ x2
Have a used engine oil analysis done to check for bearing metals too.

The Explorer OBD2 EFI 5.0 swap is well documented here and we have EFI Guy to do the harness (or teach you how if you want) and flash the PCM.

With a 5.0 HO Mustang cam and a decent exhaust (meaning NOT the stock Explorer manifolds) you should get close to 275 hp and good torque.
 

Rustytruck

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Feb 24, 2002
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10,875
Check the backlash on the timing chain and use the motor with the least amount of backlash. I would check the compression and what ever motor you choose replace the oil pump, main and rod bearings, the freeze plugs, the timing chain, the water pump and crank shaft seals. All of these parts can be had pretty cheep and easy to do while the engine is out.
 

langester

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I would also change out the cam bearings. Ford seemed to have a lot of them that didn't hold up to well. The 5.0 I just went through was similar to yours, 120,000 miles on it and the cam bearings were starting to come apart. Everything else looked decent but I changed all the internals, bearings, rings, timing set and the oil pump, seals and gaskets. Just my 2 cents, good luck with your project.
 
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betzgb

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Thanks for the advice guys. When you change rings do you need to have it bored? Can rod and main bearings be changed without grinding the crank? Same for camshaft, ok to run the old cam with new bearings? Finally, some posts say the springs in GT-40 heads should be changed cause they are "terrible" from the factory. Thoughts on that?
 

sykanr0ng

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Aug 11, 2014
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Thanks for the advice guys. When you change rings do you need to have it bored? Can rod and main bearings be changed without grinding the crank? Same for camshaft, ok to run the old cam with new bearings? Finally, some posts say the springs in GT-40 heads should be changed cause they are "terrible" from the factory. Thoughts on that?

Boring depends on the condition.
Explorer engines are well known for being found still having the factory cylinder hone marks even after more than 90,000 miles.

The Explorer cam is a torque grind, won't get the horsepower you said you want.
It and the Mustang cam I mentioned are roller cams and as long as no major failures happened they can be reused, the roller lifters too.

The springs are barely adequate for the lift of the Explorer cam, the heads on the later years are the worst at that though.
 

rguest3

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I would re-build the Explorer motor since you have everything for it.

Have a reputable shop go through the motor with all new bearings and Moly Rings (if the bores and pistons are good. If you do need pistons I would go with a Flat Top Pistons to raise compression a little.

Have the heads cleaned up and install all new valve train. I would recommend a Comp Cam XE258HR-12 K-Kit that would include Matching Parts: Cam, Roller Lifters, Timing Set, Valve Springs, Locks, Retains and Valve seals. Add some Full Roller or Roller Tip Rocker Arms.
 

Rustytruck

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Once you pop the heads and redoing piston,rings, head work you just pushed your costs out of 1500 bucks. You have to work smart to stay within your budget and get the biggest bang for your bucks.
 

Timmy390

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Once you pop the heads and redoing piston,rings, head work you just pushed your costs out of 1500 bucks. You have to work smart to stay within your budget and get the biggest bang for your bucks.

X2 it's east to say do this and do that but to stay on budget you need to really focus. If you start throwing pistons and cam kits at the Explorer motor, your budget is shot before you start.

2 years ago I did what your trying to do only with a 351w.

The 96 explorer has GT40 heads and the cam is not bad at all. Don't get caught up in HP numbers, you want torque and the explorer can does that. It's the same cam in bigger truck/van 351W's.

Save money and do the disassemble yourself. Take the block to the machine shop and have them check the bores and if good go with it. Get the deck squared up. Maybe replace the cam bearings and send it through the washer.

Disassemble the heads and clean everything and have the heads sent through the washer. Get them checked for cracks and squared. Have the valve guides checked. If good, lap the valves and reassemble with new stem seals.

Clean and reuse all the valve train.

Buy a stock engine kit. That will come with everything you need to put it back together.

Have the machine shop so the pistons and rod work

Reassemble yourself. You can do it....it's not that hard. You need the book "How to Rebuild Small-Block Ford Engines by Tom Monroe" and a few tools.

Should be right at the top of your budget and be a huge improvement over what you have now. You should be right at or just over your budget. Mine was.....

As for EFI, I did the harness myself and EFI Guy did my ECM

Tim
 

blubuckaroo

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Jun 11, 2007
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Ridgefield WA
I'd have trouble installing any used motor without a complete internal inspection first. It's really pretty easy to do.
As already mentioned, the fuel injected motors have a good history for little bore wear, but that doesn't help the timing chain and cam, crank, & rod bearings. Those can wear just as fast as in a carbed engine.
Also, if you open it for an inspection and find it all good, you have a chance to replace all the seals and gaskets.
 
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betzgb

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Dec 22, 2009
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Sounds like a plan, just open it up and see what we have and if in good shape I will just replace bearings, seals, gaskets etc. Is there a recommended engine rebuild kit you guys recommend? I noticed on summit racing they offer Federal Mogul kits but they only go up to 1995 for the Ford small block. Maybe it is better to buy all the parts independently?
 
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