1985 5.0L Mercury Capri Flo Tek Cylinder Head And Cam Upgrade Part 4

At our last track outing, we came to realize we had a leaky freeze plug. With a brown watery substance residing in the radiator, we knew the other freeze plugs couldn't be far behind in rotting away in the block. This problem combined with the fact that we were going to install a new clutch from American Muscle, led us to the conclusion that pulling the entire engine and transmission was the best course of action. Once you have the cylinder heads and the transmission out of the car, there are just the two motor mount bolts and the engine comes right out.

We took this opportunity to clean the engine compartment using some Gunk engine degreaser and a power washer. We also gave the potent little 5.0L a fresh coat of high-temperature black enamel after installing the new freeze plugs that we picked up from the local auto parts store.

In order to put the engine back together, we called Cometic Gasket and ordered its Streetpro top-end gasket kit (PN Pro1016T), which retails for $315.95, as well as the Cometic's conversion kit (PN Pro1015B), which sells for $134.95. The top-end kit includes the intake manifold, exhaust manifold, EGR, valve cover, carburetor, and thermostat housing gaskets in addition to several others. It also includes Cometic's MLS (multilayer-steel) head gasket set. The conversion kit includes the timing cover, oil pan, rear main, and water pump gaskets.

These premium gasket sets from Cometic obviously don't quite fall in with our extremely frugal budget for this project, but we took this opportunity to try the gaskets, and we're happy to report they work great on our 5.0L application. After screwing the new Flo Tek 5.0X heads on the Cometic MLS gaskets using a set of ARP head bolts from Summit Racing Equipment, it was time to bolt up the new clutch and flywheel from American Muscle.

We knew the heads and camshaft modifications were going to add a lot of power to the combination, and while we didn't really have any clutch problems at the track thus far, we'd be asking for trouble once the engine went back in with the hot parts. To that end, we called up Americanmuscle.com, which steered us towards Ram Clutch's HDX series clutch kit.

The Ram HDX clutch kit (PN 34000; $184.99) features a diaphragm-style pressure plate, 10-spline clutch disc, alignment tool, and throwout bearing. It's a 10.5-inch-diameter design for '86-and-later cars, but we opted to upgrade the factory 10-inch clutch and flywheel setup from '85 using this clutch kit and Ram's billet steel 10.5-inch flywheel (PN 34012). This flywheel uses the 50-ounce balance for the 5.0L engine, it's SFI-certified, and retails for $269.99.

Ram says the HDX clutch is good for 450 hp, which is far more than we'll be making, but considering the track abuse it will receive, it probably can benefit from some padding in the numbers. We managed to put a couple of hundred miles on the clutch before letting the hammer drop-Ram recommends a minimum of 500 miles for proper break-in. As long as you don't have any deadlines looming, it should be pretty easy to accomplish that before your start banging gears. Amercianmuscle.com makes it easy to shop for your Mustang as it has a great website with parts grouped by model year.

With the Capri up and running with the Flo Tek 5.0X heads and the B303 cam, we put as many break-in miles as we could before heading to the local quarter-mile to see what it would do. We've been having some transmission troubles with the Capri lately, so things weren't looking good, and some frigid weather-for Florida at least-didn't help the traction situation.

Previously, we had Capri crew chief George Xenos turning the wrenches and banging the gears while we took the pictures, but Xenos decided it was time to earn a real living and went back to full-time work, so we had to find another wheelman. We found two in Rob Baldwin and Chris Crosby, both of whom had pitched in on the project at one time or another. Baldwin got the nod for his proper powershifting performance of former project car Little Juiced Coupe at the track, so we kept the rookie Crosby on reserve for later.

With the ambient temperature down around 40 degrees, there wasn't much hope for the VHT traction compound that was put down on the starting line. Still, we were armed with Toyo's Proxes slicks and a poor man's suspension that really transferred some weight.