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1965 Chevy Chevelle 300 Deluxe - The Final Tune

Mark Gjavenis' '65 Chevrolet Chevelle 300 Deluxe.

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Jeff Smith came running up to us at the Car Craft Nationals to tell us about the Chevelle he had just seen, and he shouldn't be running. "Did you see that teal Chevelle? Whoa! It has a centrifugal blow-through and a big-block!" Jeff just stood there smiling and breathing.

We'd been cruising the grounds for about 11 hours, tapping guys for photo shoots and sending them off to Wes Allison for mandatory action shots. A couple of laps around the fairgrounds later, we cornered the car's owner, Mark Gjavenis, and made him open the hood and flash us the 1,000hp goods.

Mark couldn't remember why he was selling his '70 Chevelle to a guy who didn't need it, but when he got to his house to drop it off, he spotted a '65 sitting out in the cold. The buyer explained that he was simply out of garage space, so the car might stay outside over the long, cold, Minnesota winter. It was a '65 300 Deluxe sedan with original paint and interior colors, a GM disc-brake swap, a nitrous'd small-block, and a rollbar. "On the way home from dropping off the '70, I decided I had to have the '65, so I pulled over and called him. He said no, so I called him every day for three weeks until he broke down and sold it to me." Mark then drove back over and essentially gave the guy his money back and took the car.

Happy with his score, Mark pushed the Chevelle to 11.60s then pushed a piston out of the block. The replacement was a 406 from that flew the Chevelle to the same 11.60, only this time without the bottle. "I drove it around with the nitrous 355 for a summer, the 406 for another summer, and last fall, I decided to go big. There was nothing wrong with the 406, but I wanted a big-block.

"I had seen the Car Craft article ("Guide to Blow-Through Superchargers," Oct. '05) and already had a brand-new Dart M block that I bought from a friend. That's when I started to come up with all the crazy ideas," Mark says. "I was tired of messing around with 550 hp; I wanted 850 instead." The block went to local engine guy Mike Seagar, who assembled the short-block for the possibility of 1,000 hp. "I kept doing the math, and it said 1,000 hp, but no one believed me," Mark says.

Things got out of hand when the engine builder recommended adding a set of CNC-ported AFR 335 heads to the engine, and the dyno guys made a series of tune-ups that took the combination from 900 to 1,060 hp on the final tune. And they wanted more. "The dyno guys wanted to dig for more power using spacers and more tuning, but I told them this was plenty of power," Mark says. Soon, he started to realize that not only did the engine have to change but also the rest of the car. The headers needed to be custom made, and right after the dyno session, he went to Coan transmissions for a Powerglide that wouldn't split in two.

"Sometimes you don't even notice the tires are spinning until you look in the mirror and see the tires smoke," Mark says. "I was driving with a friend just below the 70-mph speed limit. Just for fun, I hammered on it. I felt the rear end shift, so I lifted. My friend said I burned the tires for 200 feet. The feeling is hard to describe." Then Mark took the thing to the track and ran high 10s. "I tried every combination of tires, and I can't get traction. But I know if I get it to hook, I will start snapping parts."

Mark refuses to cut into the stock wheeltubs because he says they are just too nice, so he thought of a new plan. "Next is more boost with a smaller pulley, an intercooler with race gas, and it will make more like 1,500 hp. It will likely become a dyno shoot-out car because that seems to be the big thing right now. I don't think it is a sleeper anymore.

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