Muscle Mustangs & Fast FordsProject Vehicles
Ford Mustang Short-Block Engine Rebuild - Recession Special Part 1
MM&FF Freshens Up A 5.0L On The Cheap Using Parts YOU Can Afford.
It Would be great if we all had 700-rwhp GT500s or 800-rwhp turbocharged, Windsor-powered coupes, but the reality is, most of us don't because we can't afford them. At the other end of the spectrum is the middle-to-lower-income enthusiast-the working stiff who has to save up for months to buy one single speed part. Most of us have been-or currently reside-in this situation, and with the escalating cost of fuel, among other necessities, money may be tight to spend on extravagant engine builds. That being said, we have a recession special designed for the average guy. It's a little more than stock, but not by much, and it won't break the bank-or your credit score.
Our subject vehicle for this build is the author's '90 5.0L, five-speed coupe. Purchased for a mere $1,500, it was in need of serious attention. With money so tight these days, this Pony has received more used and borrowed parts than anything else. It needed a set of head gaskets and an ignition module just to get it running properly, followed by a heater core/evaporator replacement and new front brakes. None of these items are exactly inspiring to an automotive enthusiast, but they were necessary if we wanted to be tooling around in a V-8-powered notchback. We scored some great deals on these replacement parts, and at present, have about $1,800 invested. It has proven to be quite reliable for the last six months, enduring an 84-mile round-trip commute each day.
Over the last two months, though, the car developed a slight knock in the bottom end, which is probably the result of the fresh head gaskets holding in the cylinder pressure better and forcing the stress towards the 169,000-mile crank bearings. We feel that the fuel mileage is rather weak at around 18 mpg, most of which is spent driving on the interstate at a leisurely 2,000 rpm. These cars were rated closer to 24 on the highway, so we think that the high-mileage missile suffers from inefficient tolerances, and we hope to pick up a bit more fuel mileage as well as power.
Things being as they are, your author doesn't have the bank to go out and buy a fresh short-block for this Pony, so we decided to throw in some new bearings, perform a quick hone on the cylinders, and fit some new rings to the factory-forged slugs. While the motor is down and out, we'll pick a mild and relatively inexpensive camshaft to liven things up a bit. We also hooked up with Thumper Performance of Orange Park, Florida, which offers some reasonably priced stock cylinder heads that, from what we've seen, are some potent performers once the die grinder has been set down.
The idea is to freshen the long-block to bring back that factory-fresh cylinder sealing. We'll do this by restoring the ring-to-cylinder-wall sealing, as well as the valve seal, the performance of the oiling system, as well as improving the induction (and the horsepower) on the cheap, all while showing you how to get the job done yourself. We'll top it off with a Cobra intake manifold, and we should end up with a powerplant that works with our 3.08 gears and makes nice power with our lint-ridden wallets. Of course, you could substitute a larger cam and aluminum heads for more power, but that will be up to you.
To minimize the amount of downtime that this commuter special endures, we opted to utilize a short-block that we already had lying around. The 5.0 mill is, oddly enough, of '90 vintage, as it came directly from the fenderwells of our former MM&FF project car ProCharged Pony. The bottom end did have 143,000 miles on it, but when it was pulled from the supercharged Mustang GT, it was in fine health with lots of oil pressure and making 473 hp to the wheels. Knowing its history and the fact that it was in good shape was all the impetus we needed to start with it rather than the knocking mill in the commuter.
To help us with this endeavor, we enlisted the help of Dave Young, tech editor for our sister magazine Mopar Muscle. Being a Mopar enthusiast, Dave often finds himself elbow deep in rebuilds of all sorts, and since this was your author's first time at doing this, it made sense to have someone handy that could make sure things were done correctly. Besides, both engines (Ford and Mopar) have the distributor in the right place.
With our subject short-block on the engine stand, we needed to pull the main bearing caps to see what said bearings, as well as the crankshaft, looked like. The 5.0L powerplant is a stout piece, capable of taking quite a bit of abuse. Our unit looked good, with no copper showing through the bearings, and no grooves on the crank journals. This was a good sign. After cleaning up the rotating assembly as well as the block, we used a stone hone on a drill, along with some 30-weight motor oil, to hone the cylinders to an even finish. It actually took longer to disassemble it than it did to perform the hone. Check out the captions for a more detailed explanation of the process.
For new piston rings and bearings, we turned to Mahle/Clevite, which had recently stopped by the MM&FF Southern Command Center. We ordered a set of standard-bore Perfect Circle piston rings, standard-sized Clevite main and rod bearings, and a stock Mahle oil pump. The oil pump will come in our next installment, but we were able to install the rod bearings and the piston rings. So far, we've got about $160 invested in this buildup, and when we're finished, we shouldn't have more than $1,500-2,000 from intake to pan.
We've broken this engine buildup into three parts so you can get a good idea of what's needed to accomplish the same goals. If you want to see more of this bare-bones notchback buildup, e-mail Editor Evan Smith at firstname.lastname@example.org, and tell him to make it an official project. It's not a glamorous venture by any means, but if you relate to it, drop him a line. We've got plenty of low-budget ideas for the ride.