In a world of small-blocks where bigger is better, the 327 still gets a lot of respect. Compared to the original 265, the 327 was obviously larger and more powerful, but where the 327 fell short was after the introduction of the larger 350. The 350 had more torque and a production lifespan that endured for decades until the end of the Gen 1 SBC.
Despite being down on inches to the 350, the 327 Chevy still lays claim to the most powerful production conventional small-block ever produced, the L84. Rated at 375 hp, the fuel-injected 327 was a high-winding screamer, as satisfying to drive as any big-block. At the other end of the spectrum, the 327 was also offered at much more pedestrian power levels, as low as 210 hp (gross). Regardless of the original output, the 327 (like any small-block), is a solid foundation for a performance build up. Like many of you, we still love the 327 and wanted to do a quick buildup with one.
Loyal readers will remember that some time back, we included the 327 in our salute to the legendary small-blocks. Taking a look back through the pages of history, we built and tested a number of the most popular and powerful small-blocks from yesteryear, including the DZ302, the LT-1 350 and the L76 327. Those of you who didn't catch the results can look online at superchevy.com—it makes for good reading.
1.Our 327 build up started with a four-bolt 350 block. The block was bored 0.030-over befo
The borrowed fuelie heads and expensive factory dual-plane, high-rise intake were all returned, but the upshot of all that testing was that we were left with a healthy 327 short- block just begging for upgrades. For those just tuning in, the short block used to simulate the 365hp L76, included a four-bolt block, a 3.25-inch (cast) crank and forged domed pistons that produced the requisite 11.0:1 compression ratio with 64cc chamber heads.
The idea behind this story is to provide a route for increased performance for 327 owners. The best way to demonstrate the merits of our modifications was to compare them to a known baseline. Given the vast number of different 327 configurations available over the years, it was difficult to pinpoint the ideal candidate. For this test, we simply relied on the L76 numbers generated previously for our legendary small-block series.
The 365hp 327 configuration served as a high water mark for factory motors, so our baseline motor was best case scenario. With the exception of the injected L84, every other factory 327 would start out producing less power than the L76, making the gains offered by our proposed modifications that much more impressive. Equipped with the legendary fuelie heads, hot Duntov cam and aluminum high-rise intake, you might think this combination would be tough to beat.
Well, time and technology have marched on since the introduction of the L76 and though it was certainly hot for its day, modern cams, intakes and (especially) cylinder heads offer huge power gains over their factory counterparts. Despite the 365hp rating offered by Chevy, run on the dyno, our L76 327 reproduction produced peak numbers of 353 hp and 368 lb-ft of torque.
2. Though the 302, 327 and 350 all share the same 4.0-inch bore, they all run different cr
3. Our build up featured a set of 6.0-inch Crower rods, though the factory rods will suffi
4. Wanting to duplicate the 11.0:1 compression used in the L76 327, the short-block featur
5. Valvetrain components were from Comp Cams. Even though we have less duration with this
6. Moroso supplied a trick pan, pump and windage tray for our 327.
7. One of the keys to performance on any motor is head flow. The Dart Pro 1 heads featured