GM Small Block Build - The Mighty Mouse of Might

Expanding Blue Thunder's performance has been my goal from the beginning of this project and I believe I've accomplished that task, both in handling and in acceleration. While some would have preferred that the entire budget went towards improving quarter-mile elapsed times, I demanded more than that from my daily driver and therefore improved its road-holding capability as well as its looks.

Having installed just about every bolt-on available for the third-gen F-body, I thought it was time to delve a little deeper into the 305 cubic-inch Chevy powerplant to see if there's any power left hiding within its miniscule 3.73-inch bore. That small bore size is really the downfall of the 305, as it reaches its maximum valve size limitations rather quickly before the valves become shrouded.

Some have resorted to notching the cylinder to make more room, but I didn't want to be grinding on the block that would remain in the car. As far as aftermarket choices are concerned, the list is short: there is World of course, and Air Flow Research used to make a 305-specific casting, but a lack of interest/buyers persuaded them to halt production.

Truthfully, there are only a handful of 305 followers who would bother to hang on to the 350's small-bore brother anyway, and going with a 350 and its 4.00-inch bore really opens up the possibilities. But I've decided to join that chosen few who like to do things the hard way, and working within those confines, the next step was to procure a set of performance heads and a bumpstick to tickle the valve springs. This search led me to World Products and its S/R Torquer 305 cylinder heads.

The Torquers are performance cylinder heads for the enthusiast on a budget. Average retail for these complete castings comes in at a little over $700 for the pair, and for this you get screw-in studs, 171cc intake runners and 58cc combustion chambers. The heads will work on any of the 265-400ci first gen small blocks, although their bigger brother sports slightly larger valves which many opt for. Along with the new heads, I planned to install a new camshaft and timing chain since both of those items have been in the car for way too long. It would have been interesting to see what the heads would do with the stock cam, but since the car would be torn apart, I couldn't resist stuffing a little lumpty lump in there as well.

Not wanting to stick just any old hydraulic roller in there, I ordered a custom unit through More Performance. What came in the mail is one monster of a cam for a street-going 350, let alone a 305. Post-install, either the wild camshaft or something else has thrown the stock computer into a frenzy, with starting and even idling being quite the chore. We managed to make one dyno pull on SLP's SuperFlow unit, but the idle and part-throttle air/fuel ratio was nearly 25:1 and WOT only came down to 14.7:1.

I had expected the computer to be out of its mind trying to tame any camshaft let alone one of this magnitude, and Ed Wright from Fastchip offered to tweak the board, but thanks to a winter storm that dropped a good 12 inches of the fluffy stuff on New Jersey, Ed was not able to make the journey to the Garden State. Therefore this tech story will be broken up into two parts. The jury is still out on whether or not the heads and cam will work, but next issue will have some results one way or another.

Part one details the installation of the World Products heads and the More Performance-spec Comp Cams hydraulic roller. To ease assembly, I called up Summit Racing for a complete Trick Flow gasket kit, as well as a new timing chain and replacement roller lifters. Aside from the usual high-mileage rusty bolts that like to strip and break, the installation was relatively straightforward. Follow along and look for the results in the next issue.

Hopefully the track will have opened and I'll be able to bring you some track times as well.

With the runner removed, you can take off the lower intake manifold. Now would be a good time to remove the headers or exhaust manifolds.	You may want to replace your water pump if you haven't done so in a while. With the pulleys removed, we used a gear puller to take off the balancer.	Next are the valve covers, rocker arms, pushrods and lifters. These are followed by the cylinder heads. There are some ground wires at the back of the heads that you'll want to make sure you reattach later on.
Our Trick Flow gasket set offered just about everything we needed. For $183, P/N TFS 31400917 gave us gaskets galore, including the 350 head gaskets that the World Products heads require.	Summit's timing chain (P/N G6601) costs a mere $42 and offers three positions for cam installation. P/N CRN 10530-16 gets you these Crane Cams factory replacement hydraulic roller lifters. Retail price is $183.	The Torquer 305 combustion chamber is 58cc, and the Manley valves use a larger 1.940 intake along with a 1.500 exhaust valve.
Here SLP tech Tony "V-6s are my bag baby" Kalapach installs the new cam. You'll need to move the center support for the front bumper cover as well as the radiator. The AC condenser also needs to be moved, but you can get away with carefully bending it out of the way.	Tony installed the cam straight up and torqued the timing chain sprocket down. This was followed by the newly sandblasted and painted timing cover and then the water pump and balancer.	The new lifters are installed, followed by the cage.
One obstacle with the head swap is that the sensor holes in the Torquer heads are too big for the stock sensors. We remedied this by hogging out some bushings and tapping them to accept the stock sensors.	Here Tony adjusts the lifter preload.	Blue Thunder's old head gaskets were on their way out. Here you can see how the fire ring around the combustion chamber started to separate. We used a set of ARP bolts (P/N 134-3601) to secure the new cylinder heads. The stock ones have seen far too many heat cycles to be reused, especially in a high-performance situation.
SLP's Brian Reese poured some silicone molds...	...	...
...of the intake and exhaust ports to show you the difference between the stock and World Products heads.	Well, Blue Thunder's back together but as previously mentioned, the computer is having a hard time dealing with its new director of air ingestion services. Hopefully Fastchip will get everyone to communicate and work together.