With fuel pressure set at 38 psi and TPS voltage set at 0.96 volt, we made our first dyno pull. Peak horsepower came in at 244 and torque twisted up to 290 lb-ft. We noticed there was a slight misfire; a replacement coil cleared up the issue and provided 247 hp and 293 lb-ft of torque at the wheels. Keep in mind, we were running the car on its 87-octane diet. For the next pull, we switched to premium 93-octane fuel and added two more degrees of timing for 14 total at base. Power rose to 249 hp and torque stayed the same at 293.
About this time, we realized that the coolant system was being pressurized, and surmised that we had a damaged head gasket. While the air/fuel ratio looked great on the dyno, and no detonation was detected, we did have some problems with what we thought was air in the cooling system. The usual procedure when refilling a cooling system is to fill it and let it come up to operating temperature so the thermostat opens. Then you can fill the remainder of the system.
The ARP head studs are next,...
The ARP head studs are next, followed by the Ford Racing Performance Parts graphite gaskets and Thumper Performance cylinder heads. The top studs go into the water jackets, so use some sealer on the end.
The heads are torqued to 55...
The heads are torqued to 55 ft-lb, 65 ft-lb, and then 75 ft-lb. You'll need to take the longer studs up to 85 ft-lb. Be sure you follow the pattern, starting from the inner bolts and working your way outward.
To assemble the FRPP 1.6:1...
To assemble the FRPP 1.6:1 roller rocker arms, insert the pedestal in the tray and then add the rocker and bolt. Then you can bolt them down on the heads following the directions provided in the kit.
Modular cars are far more susceptible to air bubbles in the system, and we thought we had ours taken care of, but the first long drive had us mildly concerned about the temp reading. A subsequent refill and about 20 minutes of idling said everything was OK, but the load that the road and dyno puts on the engine is what made the gasket vent to the cooling system. After contemplating the issue, we came to the conclusion that your author had not properly torqued down the ARP head studs. He had followed the factory torque specs at 72 ft-lb on all bolts. ARP expects you to torque the short studs to 75 ft-lb and the long studs to 85 ft-lb. The long studs run along the top, and that's exactly where the gasket failed.
In the end, we spent over $3,700 on this rebuild, but we did use some items and replaced a few others that you might not need. Without those pieces, the build price tumbles to a hair over $2,400-very doable in this day and age. Horsepower and torque are respectable and should make this Pony gallop a little faster. Whether or not the 2 hp is worth 20 cents extra per gallon is up to you. Given the long commute our project car has each day, the horsepower isn't worth the extra money. That may change, however, as we're looking to install a budget-conscious, intercooled turbo system.
With the heads now installed,...
With the heads now installed, we gave everything a couple of coats of cast-iron engine enamel.
We wanted to install as much...
We wanted to install as much as we could on the engine before installing it, as you might as well let the engine hoist do the work for you. We just couldn't see reinstalling the cheesy stock headers, so we called Brothers Performance Warehouse for a set of frugally priced 15/8-inch shorty headers. They come in a variety of finishes, but with this being a budget build, we opted for the high-temp black coating.
If we were going to leave...
If we were going to leave the car as is, Fidanza's new 1.0 Mustang clutch kit would have been fine and saved us a bit of money. However, we have some higher-horsepower plans in the works and opted for the 2.1 version, along with the nodular iron flywheel.
|Perfect Circle Piston Rings||$78.42|
|Mahle/Clevite Rod Bearings||$33.44|
|Mahle/Clevite Main Bearings||$34.72|
|Mahle/Clevite Oil Pump||$22.99|
|Crane Cam kit||$275.00|
|Crane Timing Chain||$101.97|
|Thumper Cylinder Heads||$695.00|
|Freeze Plugs ||$6.95|
|Summit Racing Roller Lifters||$100.00|
|FRPP Cobra Intake||$404.95|
|Professional Products TB||$119.99|
|BPW Exhaust Headers||$109.99|
|ARP 7/16 Head Studs||$87.95|
|FRPP Gasket Kit||$82.95|
|FRPP One-Piece Oil-Pan Gasket||$18.88|
|FRPP Harmonic damper||$64.95|
|Misc. Shop Supplies||$39.81|
|Oils, Filters, Plugs, and so on||$123.52|