In an earlier post I wrote about the Buick that embarrassed GM - the 1987 Grand National. We did some minor work on the car, fixing a few issues and installing a new oil cooler but other than that the car is basically as stock as the day it was made. Today we did a power pull on it to see what it has some 34 years later.
Here are a few specs from the time when the car was produced:
so - after 34 years and a little over 46,000 Km (not miles) on the odometer, you would expect to see a performance drop.
Here's a few shots of the car getting prepped for the dyno. After the car gets looked at on the hoist, tire pressure is checked and the car is strapped down and the dyno adjusted. From there boost sensors, back pressure, lambda, ambient air temps etc. are all connected before the warm up run. We never run tests on cold engines, for obvious reasons, so the first while on the dyno is a smooth steady run to bring things up to temperature. After that we do a run to calculate the losses produced by friction in moving parts like the transmission and differential so that calculation can be factored in.
In this case Stefan also removed the 'kick down' cable to stop the car from shifting to a lower gear under boost. We try to run as close as we can to a 1:1 gear ratio which can be tricky in a car of this era, particularly since this one has a lot of torque at low rpm. So, 34 years later...how did it do?
Well - pretty damned good.
243 horsepower pretty much flat across the range above 2000 RPM, but...402 pound feet of torque from right down at the low rpm range. The engine has that low end 'grunt' when you need it and was part of what went into making it the fastest production car of 1987. Yes - a Buick.
By the way - we are posting videos to YouTube, and the dyno pull will be going up shortly check out our channel