[Christ]

Originally Posted by JasonG

I can attest that exhaust compression brakes work very well.
They are basically a butterfly in the exhaust downstream of the turbo (yes I saw you are NA) connected to an actuator.
Really demonstrates the effect of exhaust restriction on a diesel.
Google "jake brake" for more info.
Oh, and they're fairly noisy too. Ever been next to a semi in traffic and heard that loud bbbwwaarrrrdrdrdrdrrr sound? Jake brake.
You probably won't find one sized for your car, but they are simple to make out of a biece of pipe, a rod, a 1/8" plate and an actuator such as an old popup headlight motor or an old cruise control actuator.

Check out how a pipe flue works for a wood stove. You can find those for 2" pipes, etc...

Put the rod through the pipe w/ the flue plate on it, tack weld it in place, put an arm on the rod w/ a cable attached to it, hook that to a lawnmower throttle control handle. When you need extra braking, that would be as simple as flipping the handle.