From: "Greg Goulden" To: Subject: Re: [DTLC] engine brakes Date: Sun, 7 Dec 2003 21:45:45 +1100 Reply-To: dtlc@helios.net ----- Original Message ----- From: > > > Is anyone using the exhaust brake that Toyota makes for the 13B-T, 1HZ or > 1HD-T engines? If so how effective are they? > > I drove an HZJ77 with one on it and it sounded cool but I didn't go down > any big long slopes..... > > Dave Stedman Dave, I did once try an exhaust brake from a light truck on my HDJ80. Fairly standard 3 bolt flange unit bolted straight to the turbine outlet, and with a little custom machining even used the Toyota crush style gaskets each side. All I had to do was shorten the dump pipe some. The dyna ones are vacuum operated, as I had compressed air on board I used a simple solenoid and air actuator to operate it. On the lower compression ratio TD, the effect was more noticable at higher rpm (say 2000+), but for off road decents it would allow you to use one gear higher and still peg rpm back. On the higer compression ratio 1HZ for example, it should perform better at lower rpm. Fitting it at the turbo outlet does cause some gas restriction, and I'm guessing a sudden drop in turbine rpm when triggered (shock load?). If I was to do it again, I'd fit a bigger ID unit, and mount it at least a couple of feet from the turbo so that when triggered the time taken to compress the gasses would slow the turbine more gradually. Regards, Greg Goulden 2000 HDJ105