Note: Stock baseline set with 10 degrees ignition timing and underdrive pulleys. The X302 figures reflect 13 degrees ignition timing and stock pulleys. Stock torque would improve with more timing; X302 power would gain with underdrive pulleys.
Transmission Upgrade
Because our '91's T-5 gearbox had 198,000 miles on it and was making increasingly more gear whine, we installed Ford Racing's M-7003-Z transmission as a replacement. This is the world-class version of the venerable T-5, a transmission we've come to love for its light shifting and minimal weight.
Easiest of all to install...
Easiest of all to install was our new Ford Racing aluminum driveshaft-just slide it in and bolt it up with the stock bolts. Curious, we first pulled out the bathroom scale and found the stock shaft checked in at 19 pounds, the FRPP aluminum replacement at 14 pounds, so we saved 5 pounds right here. After the driveshaft, the exhaust can be hooked up. Expect a different fit with new headers. We ended up with a small leak our muffler shop cured by cutting and re-clocking the belled end on the right X-pipe-to-header flange. A common fix, says Ricardo.
There are few difficult operations...
There are few difficult operations in a 5.0 engine installation, but a couple of spots might try you patience. Ricardo has found a sawed-off 11/8-inch open-end wrench a big help. It's an easy fit for the water pipe at the intake manifold and the EGR fitting on the passenger-side exhaust.
You'll need the entire front...
You'll need the entire front engine dress off your original engine, especially the brackets and bolts. It pays to get these parts cleaned as much as possible before installation, and if you're building a looker, you'll want to consider paint, powdercoat, or phosphate wash, etc., as these parts are typically unpainted and a little rusty under the dirt and grease.
Compared to our tired stocker, the M-7003-Z features upgraded synchronizers and bearings; a steel input bearing retainer; more torque capacity at 330 lb-ft; a short-throw shifter (not too short and fun to shift); double-moly second, third, and countershaft cluster gears; carbon-fiber third/fourth blocker rings; and a Cobra-style pocket bearing. The rest is compatible with the stock trans, with a 28-spline output shaft and seven-tooth speedometer drive gear, so it bolts right in.
| T-5 Gear Ratios |
| Gear |
Stock '91 |
FRPP |
| 1 |
3.35 |
2.95 |
| 2 |
1.99 |
1.94 |
| 3 |
1.33 |
1.34 |
| 4 |
1.00 |
1.00 |
| 5 |
0.68 (0.675) |
0.63 |
To match our 24-lb/hr fuel...
To match our 24-lb/hr fuel injectors, we swapped our mass air electronics into a C&L mass air housing. This is a direct swap, with the C&L housing accepting the stock meter bracket and air inlet tube.
Installing our Edelbrock 70mm...
Installing our Edelbrock 70mm throttle body and EGR spacer was dead simple once we pulled the four long mounting studs from our old upper intake manifold and got them in the new RPM II upper intake. All necessary gaskets are supplied; the final step was setting the TPS voltage with a digital voltmeter.
The thicker Ford Racing radiator...
The thicker Ford Racing radiator causes a mounting issue along its top edge. Ford uses two bolt-down U-stampings for the stock radiator, and the recommendation to bend those clamps wider to accept the radiator violated our sense of aesthetics and mechanical propriety. Steeda has a great answer for this; a simple aluminum piece that bolts into the stock holes and puts a light spring pressure on the radiator. Available in many color and logo combination, we opted for the black version.
As the chart shows, the gear ratios are slightly different. Clearly the taller first gear combined with our crate engine's lower off-idle torque, choppy idle and stock 3.08 rear axle gears means starting from a dead stop is something of a small event, requiring a touch of technique. We stalled the engine numerous times until we ingrained the slight rpm increase and clutch slip required; now it's second nature. Curiously we find the taller first gear handier in parking lots, on super bumpy roads, and so on, but maybe not as brainless in crawling stop-and-go traffic.
Another consideration is speedometer error. Of course, we can ignore the First gear speedo error, Second and Third are close enough to not count, Fourth is identical, leaving only Fifth as an issue which we're probably just going to live with. In the real world, the speedometer is "slow" by about 6 mph at 70 mph in our pacing tests, so we remind ourselves we're going faster than indicated on the freeway. Ssadly, the odometer no longer reflects the exact mileage, but it's close enough for maintenance work.
What is to like about the ratios is the slightly taller Fifth gear makes flying along with the reality of 80-mph freeway traffic easier, plus it's beneficial for fuel economy at less frenetic cruise speeds. What was unexpected on the freeway-and has nothing to do with such minimal gear changes-is the noise level of the exhaust. The only new exhaust bits are the short-tube headers; the sound quality is the same-there's just a bunch more of it.
Our in-tank fuel pump was...
Our in-tank fuel pump was whining like a big dog, so we had GTR fit a new 190-lph pump to ensure our new X302 didn't starve for fuel. As is typical, says Ricardo, the rubber gasket between the fuel tank and filler neck was cracked and disintegrating, so he replaced it. At this age in the LX's life, consider this a normal part of fuel tank service. Ricardo does, and he keeps a ready supply in stock.
It might not seem like part...
It might not seem like part of a crate engine install, but the vital tires and brakes should be considered because you'll be zooming around with more power. Our tires were totally shot, so we fit this set of Continental Extreme Contact DW's in the stock 215/55ZR-16 size. Our brakes didn't require any service, but we assure you, we're using them and these tires much more than with the old engine! The Continentals have proven especially quiet tires-at least as much as we can tell over our suddenly louder exhaust.
After plenty of work, here's...
After plenty of work, here's the finished product. The X302 transformed our mild and tired 5.0 into a real player, complete with stuttering idle and rev-happy power. Cosmetically we'll likely paint the top of the aluminum radiator black to blend it in better, and spend a few minutes with some electrical tape, black cable ties, some ignition wiring separators, and other details to give the cleanest look possible.