At this point a custom tune was
required to pull the modifications
together. Michael enlisted the help of pcmforless.com in Mooresville NC
according to Mike they supplied him with a mail order tune that
performed flawlessly. The new tune pushed the car to a respectable
12.62 @ 109.53 mph, the 60 foot times timed out at 1.89.
In an effort to improve traction
and the cars 60’ time Michael decided
to try a set of MT ET Drag Radials. To improve durability a Dana 44,
with 3.73 gears and billet bearing blocks was installed. In the quest
for more power, Mike purchased a set of Trick Flow185 GenX cylinder
heads. The castings were exceptionally good as cast, but he decided to
clean them up a bit with some porting and polishing. Comp springs and
retainers were then installed at 1.785". Comp 7.290 hardened push rods,
guide plates and ARP rocker arm studs finished off the valve train. The
engine was then topped off by a Lloyd Elliot ported intake, 30 # SVO
injectors and a Performance Products 58mm throttle body. A Racetronix
255 lph fuel pump was then installed to insure that the larger
injectors were getting adequate fuel flow.
The cars new power curve revealed
a weak link in the C4 drive train.
The 3-4 clutch pack in the stock 4l60E automatic transmission failed
shortly after the head swap. Mike dropped the stock 4l60E and upgraded
it with an 8 disc 3-4 pack, and a Transgo HD2 reprogramming kit.
the transmission was already out, he decided to install a Yank PT4000
converter that was better suited to the new engine combo. With the new
heads and higher stall, the car showed a significant improvement by
running a 12.09 @ 113.03.
The power mods to Michaels
C4 have proved to be very street able. Mike
extends his wholehearted thanks to all his good friends for helping him
to build a very quick C4.