VIDEO: Stock Bottom End GN Nipping at The Tens

The Grand National is just one of those cars that has a unique place in the GM EFI landscape. It wasn’t a vehicle that was over mass-produced; like a Cavalier or a Civic. This Buick has a niche following that brings a group of brand-dedicated folks with it that make the nameplate truly special.

Today we explore Scott Jackson’s GN build. Starting from the ground up, the car is one of just over 5,000 Grand Nationals built in the year of 1986. At the heart of the beast, we have a stock bottom-end 3.8L LC2; that’s right, just 231 cubic inches of Buick V6 powers this machine.

On a previous setup, the car was able to sneak into the 10s, clocking in at 10.97@123, but then the turbo unfortunately decided that it would be no more. The mangled Limit Engineering TE-62 turbo would be replaced with another 62mm unit, this time it would be a billet wheel turbo boasting the Precision name.

Digging a bit deeper into the build, we find forged pistons and a custom 210/215 COMP Cams roller camshaft with .517 lift. The car retains the factory 8445 heads, but they’re ported to flow a bit better.


Looks mostly, stock – and that’s because underneath the high-lift camshaft, ported heads, and upgraded turbo system, it’s standard fare LC2!

Top it all off with a little bit of methanol via AlkyControl single nozzle progressive alcohol injection and you find yourself in a boost friendly environment. Most of the rest of what resides under the hood remains stock or stock replacement, making the times all that much more impressive.

Moving toward where power meets pavement, we find an original 200-4R trans (borrowed from a WH-1 T-Type) with a 3400 stall ProTorque 9.5” billet torque converter. The transmission is equipped  with a shift kit and the power is then unleashed through an original 8.5” 10-bolt rearend with a 30-spline Eaton posi unit and 30-spline Moser Engineering C-clip axles.

With a relatively mild setup, the car is currently good for solid low 11s, but we think with some tuning on the owner’s end, along with a few more traction aids, and mid-10s should be easy to accomplish. Make sure that you check out the machinery behind the little-V6-that-could in the video above!


Even with the chrome of the ’86 grille, the Grand National always had an intimidating presence from the front.

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