A couple of months ago, we rolled our '84 Z28 out of mothballs and put it in primer ("Primed and Ready," Mar. '07). This month, lest you think this particular Camaro is destined to be all show and no go, we're adding some go-fast parts to the mix.
You know the score: Third-gen Camaros are very affordable performance platforms. On the other hand, many of these cars--especially the early versions--need a lot of help in the power department. In a nutshell, that's where we're at with our subject. It's a challenging mission, since we're embarking on what many consider a fool's errand: extracting more power from our third-gen's original 305ci powerplant.
Why bother, you may ask. Despite its shortcomings, many of you want to see what we can do with the ugly duckling of Chevrolet's small-block lineup. Truth be told, we want to give it a shot too. These engines ended up in tens of thousands of cars from the mid-'70s through the early '90s. Plain odds dictate that some people will want to use a 305 for their performance build; many others will do it out of necessity, creating an engine piece by piece--sort of like what we're doing here.
Despite our Z28's haggard appearance, we've actually got a decent starting point. Our $1,000 eBay find came with an RPO L69, 190hp H.O. motor made available in '83-86 Camaros. In the performance wasteland that was the '80s, this engine was one of the more potent mills around. Ours was still in good shape. The car's odometer showed just shy of 75,000 miles when we got it, and after our friend Ralph Serrano at D&D Service rebuilt the untouched, computer-controlled Quadrajet, the thing was a decent little runner. Our baseline numbers, recorded on Primedia's Mustang chassis dyno, backed up our hunch. While 158 hp and 181 lb-ft of torque are well south of impressive, let's do the math. The L69 motor came rated at 190 hp at 4,800 rpm, along with 240 lb-ft at 3,200 rpm, both measured at the flywheel. Subtract 20 percent for driveline loss through our 700-R4 tranny, and we're right in the ball park.
That's the good news. The bad news is that our properly functioning, stock L69--fitted with factory-optional 3.73:1 gears and a set of BFGoodrich drag radials--could only propel our Z28 to a 16.59 quarter-mile, with a rip-roaring trap speed of 83.15 mph. OK, we know various magazines reported much faster test times back in the day, when these cars were new. It'd be hypocritical of us to say that you shouldn't believe what you read, so we'll just say that today, in 2007, our example was good for 16s. It was definitely time to get to work. Of course, here in California, we couldn't undertake this project without considering the smog police. We want our Z to be street legal, so it has to be able to pass the test. Put bluntly, our philosophy was this: Anything that can be seen on the car has to be legal for use in Cali and have the necessary EO (executive order) number to prove it. Anything that's not immediately visible, in our book, is fair game--as long as the car passes the sniffer test.
Our first stop was the Primedia Tech Center, where we began our quest for power by upgrading our Camaro's exhaust system with an Edelbrock after-cat system and TES headers, teamed with a Random Technologies Super Stainless catalytic converter. The improved flow provided by this setup netted us some nice power gains, but we also installed the new system in anticipation of what was to come: a set of Trick Flow's Small Chevy cylinder heads. We'll give you more details in the sidebar, but for now we'll point out that these lungs are made especially for 265-305ci engines and, best of all, they're smog legal. Trick Flow also hooked us up with a matching hydraulic flat-tappet cam. It's small, by the standards most of us are used to, but remember we're working with the smallish 3.736-inch 305 bore, and trying to keep the thing smog legal.
In the end, we came up with a real "good news, bad news" scenario. The good news is that our bolt-on barrage netted us gains of 53 hp and 45 lb-ft of torque, which lead to a 1.29-second drop in our quarter-mile time. The bad news is that our Z is still slow. But there's more good news: We haven't yet dialed in our subject's Q-jet to work with the new combo, and we've got some other ideas floating about, so there are certainly more gains to come. These are only the first ingredients added to a little Camaro concoction we're calling The Mulletov Cocktail, and so far, the mix looks good.