
Hello, my name is Kevin and welcome to my 1994 Pontiac Formula page. I ordered this car from the factory in December of 1993 and it arrived the following March. I did my first major motor modifications back in 1997 when the car had 48,000 miles on it. At that time I installed a TPIS ZZ-9 cam and had my cylinder heads mildly ported. This and a good exhaust was good for 320 RWHP and 340 lb/ft of torque on a Dynojet chassis dyno.
In January of 2003 with 98,000 miles on the odometer I experienced a broken valve spring on my #2 exhaust valve. As a result of the broken spring a piece of the valve guide boss broke off and pieces of it damaged 2 other pistons. The #2 piston itself was pretty beat up from the bent exhaust valve and the #3 and #5 pistons were damaged by pieces of the valve guide boss. The end result was 3 damaged pistons, 1 cylinder head with a bent valve and broken guide boss.
I had not planned on rebuilding my motor but was left with few options. I had the short-block machined and assembled by Mike Criss at Criss' Engine& Machine Shop here in Tucson. They did a very nice job on my motor and I would recommend them to anyone in this area looking for a good machine shop. The Cylinder heads were sent out to Advanced Induction in North Carolina for a full port job and bigger valves. The heads took about 5 months to get back but when they arrived they looked great. The following components were used in the build up:
|
Lift |
0.100 |
0.200 |
0.300 |
0.400 |
0.500 |
0.550 |
0.600 |
|
Intake |
68 |
139 |
197 |
238 |
263 |
269 |
272 |
|
Exhaust |
51 |
108 |
142.5 |
176 |
189 |
192 |
194 |
This link is to my Electric Water Pump Current Monitoring Circuit
I had my car Dyno tuned at Pro Dyno in Tempe Arizona. The techs there were very helpfull and I really had a good time learning about the tune in my car. We used my copy of LT1 Edit and my laptop to do the tuning. The first dyno run showed that my car was running lean at all RPMs. After 12 dyno runs and reprogramming my PCM 5 times we gradually enriched the Air Fuel Ratio to get me the best run that my current set up could provide: 410 RWHP and 392 lb/ft of torque. Dyno Plot
The dyno tech that was tuning my car told me that this motor still had some more in it. He said that he was not able to acheive the desired Air Fuel Ratio he wanted at torque peak. He indicated that If I upgraded my fuel pump and injectors their could still be another 10-20 HP to be had. Needless to say I have started saving for some 36-38 lb/hr injectors and a new Walbro Fuel Pump.
Last updated 20.6.2004