Next we bolted down these awesome-looking valve covers from ProForm and topped off the Edelbrock intake with the Barry Grant Speed Demon 750 carburetor. The Speed Demon will offer excellent drivability, idling characteristics and most of all - power!
Finally we installed the ProForm HEI race distributor (PN66941R), which comes complete and ready to use, providing 50,000-volt spark through 7,500 rpm. Now for the moment of truth. We packed up and headed over to B&B Performance Machine in Rahway, NJ, to get the digits on our revamped 350.
TFS ProCharged kit
Once the mouse was mated to the SuperFlow engine dyno, it fired right up with 40 psi of oil pressure and sounded mean. After a few jet changes to the carburetor (we settled on 77 primaries and 84 secondaries), and multiple timing adjustments (37 total worked best), the numbers were in. TFS rated its kit at 445 hp and 40 5 lb-ft of torque. We squeezed out 428.4 hp and 421.4 lb-ft of torque-a little shy on horsepower, but way up on the torque side. Remember, we're using an old, low-compression, smog-compliant short-block, which after being topped with the TFS package checked in at a still low compression of approximately 9.0:1. TFS recommends a minimum compression of 9.5-10:1.
Now that's impressive, and adding a flat-top piston to the equation alone will net us well over 450 horse! We took a worn 350 short-block equipped from the factory with low compression, threw a total of around $2,500 worth of quality components at it, and gained 253 hp over the stock rating. That's about ten bucks per horsepower. And we ended up with a serious street/strip slayer that can run on 87-octane gas all day long!