5.0 Mustang & Super Fords
2005 Ford Mustang 427 - Fast From The Past
Adding Historic 427 SOHC Power To Jim Weigle's Modern Mustang Was Surprisingly Easy
To make life more interesting, Jim had Tony fit electrically operated exhaust cut-outs at the end of the headers. Jim can flip a switch and go loud whenever the spirit moves him. He says that never fails to attract a crowd right away.
Tony also rigged up a serpentine beltdrive for the front of the Cammer. It conserves engine length and accommodates the air-conditioning system retained from the new Mustang. The remaining S197 computers didn't know what to do regarding the air conditioning with the engine-management computer missing so much input, so Jim and Tony couldn't get the A/C to start. The problem was fixed by running a toggle switch to the A/C relay.
Atop the Cammer, the dual four-barrels needed an air filter that would clear the hood. Jim made one by modifying an existing dual-four FE filter.
It should be no surprise that Jim is a manual-transmission sort of fellow. It's also no surprise that there was no way the stock Mustang GT five-speed was going to last five minutes behind a Cammer. Instead, a Tremec T56 gearbox and associated bellhousing, McLeod twin-disc clutch, Hurst shifter, and aluminum driveshaft were sourced in a package deal for about $5,600 "from some place Tony found in Detroit." Interestingly, the shifter sprouted right through the stock hole in the transmission tunnel, so no butchery was involved in fitting the new driveline. The rear axle was left completely unchanged.
The only change to the chassis has been Eibach Pro System lowering springs in the rear. The front springs remain stock, as they compressed under the weight of the Cammer sufficiently to give the desired lowered look. The lower rear springs were substituted to bring the rear down to match the front.
If the project seems too easy so far, it's because the real problems were with the engine. Jim contracted with an engine builder for the all-aluminum 427 SOHC seen in the photos. This is a pricey item to say the least, considering we've heard of tariffs ranging from $20,000 to $35,000 for all-original Cammers. Rolling your own lightweight from a $6,000 Shelby aluminum block, compared to what can be up to $9,000 in dressed- and prepped-aluminum Cammer heads, doesn't seem to be such a crazy alternative.
Jim's sad story is that the first engine blew up in the car almost immediately. It was removed, repaired, and then blew up on the dyno. Jim decided the next thing was to break out the lawsuit hammer. In the meantime, he contracted a new builder, Bob Chenoweth, for a second Cammer.
The first engine, the one we're looking at in the photos, sported custom camshafts and dual-quad, 780-cfm Holleys. As shown, this engine posted 662 hp at 6,900 rpm and 545 lb-ft of torque before letting loose on the Superflow dyno. It has also run long enough in the car for Jim to get some good impressions on what the finished product will be like-fast.
Because Jim believes all the available aluminum cylinder heads are "junk, just junk," he's going with a different aluminum block and original iron heads on the new engine. A billet crank and good rods are planned, so it's an all-out effort. It will likely wear the same pair of rare, Cammer-specific Holley carburetors and easily break the 700hp barrier after the porting and camming Bob is building into it. We'll be curious to see how the dissimilar coefficients of expansion between the block and heads get along in such a performance engine.
As we went to press, Jim was waiting for his new camshafts to get back from heat treating, but he could brief us on his unique Mustangs personality.
It's fast. Just how quick, no one knows-it has never run against a clock or done any sort of track driving. We thought wheelspin would be an issue, but Jim says it's not. "The Cammer really doesn't make any power until 3,400 rpm, so it can be driven around town without constant worry of wheelspin from every light." He says the 245/40-18 Goodyear Eagle F1 tires on the Ford Racing wheels do a surprisingly good job of holding on to the power, but will instantly go up in smoke if he's abrupt on the clutch or slaps the throttle with any rpm on the clock. Be careful going into second gear and still mindful selecting third, "or you're going sideways."
As for top end, Tony says the big unit easily pulls 4,000 rpm in Fourth, which is 140 mph. Jim would do such testing himself, but says, "I'm too old; that top end scares me." Smart man.
The only teething problem was the water temp. The engine would run hot, belch coolant, then run coolly for awhile before overheating again. Jim cured this by substituting a 427 FE thermostat in place of the Three-Valve's, as well as drilling two 1/8-inch bypass holes in the thermostat for good measure. The coolant temperature has run perfectly ever since.