When you do a clutch job,...
When you do a clutch job, it's always a good idea to pop for a new pilot bearing for the back of the crankshaft. Once that was installed, the Ram billet steel flywheel was mounted next using some thread locker on the bolt threads.
Having previously launched the car at 5,500 rpm, we thought it wise to back the launch rpm down a bit to compensate for the cold track. Baldwin held the throttle at 4,500 rpm and popped the clutch on the third amber. The tires spun badly and when he dialed up Second gear, Baldwin was put on "shift waiting." Once he found Second gear, he pulled the engine up to 5,800 rpm (a feat that wasn't possible before the new heads due to valve float) and shifted the remaining gears to cross the finish line in 15.47 seconds at 104.35 mph. The heinous 3.19-second 60-foot time told the whole story. Baldwin's second pass was much better.
Dropping the launch rpm to 3,000, the Capri spun slightly but moved out to a 1.92 short time. Three gear changes later, the clocks lit up with a 12.89 at 107.99 mph. It was going to be a challenge to get the Capri to leave hard without spinning, so on the next pass, we lowered the tire pressure from 15 psi to 13 psi. We also opted to rev the engine a little higher on this next run, and a 3,000-rpm launch followed by 6,200 rpm shifts turned a 1.88 60-foot time into a 12.74 at 107.88 mph. Baldwin reported that the car didn't feel like it pulled that high, so for run number four, we backed shift points down to 6,000.
The Ram clutch setup was next....
The Ram clutch setup was next. The flywheel did not come with dowel pins, but luckily we were able to pirate some from another project. The factory clutch bolts were the wrong pitch thread as well, and we had to drop by the hardware store for some metric fasteners. If you're ordering head bolts from Summit Racing, you can order these at the same time.
At this point, we handed the keys to the rookie, Chris Crosby, who runs low 12s with his naturally aspirated heads/cam/intake Fox-body coupe. Crosby specified 12 psi of air in the tires and attempted a 4,000-rpm launch, to which the Capri responded with bad wheel spin. Crosby aborted the run and wheeled around for another go. This time, a 3,000-rpm launch resulted in mild wheel spin and a 1.88-second short time, followed by a 12.80 run at 107.97 mph.
Crosby followed this up with a final run of 12.61 seconds at 108.74 mph-a better 1.82 60-foot time surely helped. With a lot more air flowing through the engine and cold dense air being sucked down the carburetor, we thought it was time to try a jet change, which is something we have wanted to do for a while now, but couldn't until Holley set us up with a complete jet kit.
With the cold weather and...
With the cold weather and track surface, we were forced to launch the car at a somewhat soft 3,000 rpm rather than 5,500, which worked at our last track outing. Because of this, our 60-foot times were subsequently off. Nevertheless, we still dropped a second off our best elapsed time, but there is more in the car, so we'll be addressing the suspension next.
For run seven, Baldwin jumped back in the hot seat after swapping out the Holley's 65 jets for a set of 70s. We opted to make a big change in the sizing to see a good change one way or another. As it turns out, that plan didn't exactly work. Baldwin let the clutch fly at 3,500 rpm and the Capri responded with a 1.88-second 60-foot time. It crossed the stripe in 12.84 seconds at 107.53 mph. At the driver's request, we ditched the paper air filter element and air cleaner, and headed back to the starting line.
The staging lanes closed at this point, so this would be our last run. Baldwin took a risk and left the line at 4,500 rpm. The first 60 feet passed by in just 1.75 seconds-our best time of the night. The timing lights lit up with a 12.54 at 108.72 mph. That's a full second off our previous best e.t., and a gain of nearly 9 mph. The Capri is definitely making some steam thanks to the Flo Tek cylinder heads and the B303 cam. Not bad for budget parts.
As triumphant as the last run was, it was also the scariest looking. The car hadn't made a straight pass all night, and Baldwin went near the center line twice. The Capri wanted to launch left every time and unloaded rear tires pretty good at every shift, so we think we have some suspension work ahead of us. With the help of Lakewood Industries and Moroso, that's our plan for next month. We're also going to finally drop the front antiroll bar (yes, it's still on there), as well as maybe add a few more ponies with a couple of small bolt-ons that we've passed by.
Are 11-second e.t.'s possible for our Capri? Come back next month and find out.
Making jet changes to the...
Making jet changes to the 4160-series Holley carburetor is pretty easy. Place a container or numerous rags beneath the front bowl to catch the extra fuel that comes out after you remove the four front bolts; then the jets turn out with a stubby, flat blade screwdriver. In a pinch, a penny will work too.
Holley provided us with a...
Holley provided us with a jet change set so that we could fine-tune our combination. We only had time to make one change, and we pulled the 65s that were in the carb and replaced them with 70s. We didn't really see any change in performance despite such a large numerical change in jet size. Pulling the air filter didn't do anything either, so we will look into a possible fuel supply issue as the reason for the lack of change.
Rather than use a typical...
Rather than use a typical parts store tire pressure gauge, we contacted the folks at Moroso to get one of their Pro Series tire pressure gauges (PN 89560), as well as some Race Write marker paint for the track. The Race Write stuff works great, wipes off easily, and even works when its 40 degrees outside.