Building a 1,000hp mod motor...
Building a 1,000hp mod motor is as easy as combining a properly prepared Four-Valve long-block with efficient boost and tuning. After upping the boost pressure to the 17-psi mark, we were rewarded with peak numbers of 1,002 hp and 832 lb-ft of torque.
Overkill. If some is good, more is better. But we've learned that in terms of building reliable and useable street power, taking the more conservative route is often better. Once you get past the 500 or 600hp mark, it's hard to keep street tires planted long enough to enjoy the acceleration. Sometimes, though, it's better to go for the ultimate, and this is one of those times.
For this buildup, we wanted more of everything-more cubic inches, more flow, and even more boost. Starting with the 5.4L Lightning, Ford took aim at the performance truck market with both barrels smokin'. It followed the blown Lightning with the 4.6L Terminator motors and, of course, the Ford GT, and now the Shelby GT500. By combining the 5.4L displacement with Four-Valve heads, Ford designed a recipe with all the best aspects of the supercharged Lightning and Cobras to produce one exceptional Mustang.
When you go looking for 1,000...
When you go looking for 1,000 hp, displacement is a welcome part of any buildup. Rather than opt for a typical 4.6L, we stepped things up to a full 5.4 liters of displacement from SHM.
The Shelby GT500 is the cream of the proverbial Mustang crop-that is, until the more-powerful KR version is released next year. We decided, however, it was time to combine displacement with more forced induction and built our own 5.4L. The benefit of the 5.4L over the smaller 4.6L is obviously that the additional cubic inches add power. Given an identical specific output, the 5.4L motor offers an increase of over 17 percent over a similar 4.6L. What makes the larger 5.4L even more appealing is the fact that it doesn't just offer 17 percent more peak power, but 17 percent more power everywhere, from idle to redline.
If there's one area where the normally aspirated modular motors are deficient, it is in low- and midrange torque production. Ford cured this by adding superchargers in various applications, but for the atmospheric reliant engines out there, they can surely use the boost in torque production offered by the increase in displacement. There's nothing more satisfying than sticking your foot in the throttle and being rewarded with some serious grunt.
The SHM 5.4L short-block featured...
The SHM 5.4L short-block featured a steel crank, forged rods, and pistons. A beefy bottom end is paramount when looking for four-digit horsepower.
To achieve the desired displacement, we put a call into Sean Hyland Motorsport. The mod motor experts assembled a 5.4L short-block featuring a steel 4.165-inch (stock stroke) crank, forged rods, and pistons. Though the aluminum GT block-suitably modified for wet-sump use-or even the SHM 6.0L block would certainly be high on the wish list, we settled for a good old-fashion iron block. Given that mod motor maniac John Mihovetz exceeded 1,300 hp with a factory iron 5.4L block, we felt confident at our significantly lower power level.
What we needed was a bulletproof (if such a thing actually exists) bottom end that was ready and willing to accept the amount of abuse we had planned. The 5.4L short-block from SHM provided the necessary strength and displacement to help us achieve our goal of 1,000 hp. The improvement in average power production from the large-displacement 5.4L offered another benefit, namely an improvement in the response rate of the turbos from HP Performance. Obviously it takes serious turbos to produce 1,000 hp, and the higher the flow rate of the turbo(s), the less responsive they become. Running a larger motor allows use of larger turbos without paying a penalty in boost response-in this case, bigger really is better.