Budget Ford Mustang Build - Back-To-Basics Budget 5.0 Buildup Part 1 - Tech

First PassesWe arrived at the Mooresville track with a shade over 225 rwhp on the motor and some 65 more with the nitrous in action (jetted with 75hp jets). If everything had been perfect, I would have expected about 20 more than that, but it was OK considering the high mileage. After a weigh in, we found this 225 (or so) horsepower had to propel 3,140 pounds of car plus a 200-pound driver down the strip.

Getting to the track early meant that both Nate and Dusty could get in a fair number of passes. Nate made the first of these, and a couple of major go-slow issues became apparent even on the initial run. First, three-year-old drag radials will not hook up like three-week-old ones. Secondly, the limited-slip diff was not limiting slip, as one rear wheel made smoke like a Navy destroyer putting down a smoke screen. The best either Nate or Dusty could do for the 60-foot and eighth-mile times was a mite under 2.2 and 9.3 seconds, respectively, with a terminal speed best of 76.8 mph. Run-to-run, the wheelspin issue made for inconsistent e.t.'s. Hitting the nitrous usually resulted in a slower time because the tires would now break loose even in Second gear. Running the best numbers through our computer program showed that the 9.3-second and 76.8-mph eighth-mile related to a 14.51 at 94.7 mph.

It was not clear just how much each of the two traction problems was contributing toward slowing the car. The diff had to be fixed regard-less so that the car would perform on road courses, so with a $50 repair kit from the local Ford dealer, Nate rebuilt the rearend.

At the next Mooresville session, things looked better. The diff fix made its mark by dropping the 60-foot time by a tenth-and-a-half and the e.t. by about two-and-a-half tenths. The first few passes were made in the heat of the day, and we had some 60-foot times just under 2.1 seconds and some eighth-mile runs at a few thousandths over the 9.1 mark. When things cooled off we made some more runs, but it seemed there was nothing that would induce this machine to run a sub-2-second 60-foot and sub-9-second e.t. At the end of the day, the best we could do was a 2.043 and a 9.044. The speed nudged up slightly to 77.2 mph. For the quarter-mile, this equated to 14.13 at 96.7 mph. Not bad for a cash layout of just $2,862.

Even though traction was a big problem, it was deemed worthwhile by all concerned to make a run using the nitrous. For the record, the big traction problem turned into a major traction problem, even with the Zex's 75hp jets installed. The plan was to use the nitrous only in Second and Third gears. E.t.'s were all over the shop, though. The nitrous system's torque punch was often enough to blow the tires off this car in Second gear. Most runs were actually slower than those without the nitrous, but one run did sort of hook up and netted an 8.77 at 81.9 mph. For the quarter-mile, this equated to 13.57 at 100.7 mph. A typical street cost of the Zex nitrous system was about $530, putting the car up to just a shade under $3,400. But, remember, we only used a 75-horse shot, and traction was a real issue. I was in a similar situation with my 5.0 about four years ago.

With about 270 rwhp, the car was on BFGoodrich Comp TAs, running around the 13.65 mark at 100 mph. The 60-foot times were right on 2.00 seconds but never under. Here, Dale from Custom Performance stepped in and loaned me a brand-new set of BFG Drag Radials. This was worth an instant one-and-a-half tenths off the 60-foot time and three-and-a-half off the quarter-mile time. Applying that to our Comp Cams project car would have put our times conservatively at 8.8 at 78.4 mph for the eighth and 13.91 at 98.0 in the quarter. All this would have been for $3,107 and certainly a little more to come with fine-tuning.

With just the 75-horse shot added to the equation, we would have been able to use the nitrous pretty much right out of the gate. The computer simulations indicated this would have resulted in an 8.45 at 84 mph and a 13.2 at 103.5 for the quarter-mile. To achieve this would have set us back $3,640. Figures like this have to prompt the question as to whether or not we can get this car into the 12s for under $4,000.

At this point, we have a respectable-looking, quick-running car. Also, we have reached this point without any really serious mechanical work. Next month, we will look at an alternative route to a 13.2-second quarter. We'll achieve it without the nitrous yet still hold the total vehicle budget under $4,000. This will include how to rebuild an engine for less than $300. When that's all rolling, then we will hit the nitrous once again-12s here we come.