jake brake

[2dogs]

does anyone know if the 87' 8v92 has the high/low installed and just need the wires connected?? 8% grades every trip!! we have low--(on-off) thanks for any info.....

[fulltiming]

Are you sure you just have the low connected? On the '90's Newell's with DDEC-2 8V92's with a single-stage Jake brake it activated all 8 cylinders. Jake's don't provide the retarding power on a two-stroke as they do on a four-stroke. Mine got better after the Detroit Diesel mechanic found a broken wire under the valve cover that was preventing the Jake on two cylinders from activating so I was only getting benefit of the Jake on six cylinders instead of eight.

Jakes work better at high rpm's so keep the engine speed up in the 1800-2100 range to maximize the affect of the Jake. Detroit Diesel did make 8V92's with 2 speed Jake's but I don't know if Newell ever used them.

In 1989, Jacob's released a Jake Brake Tune-Up Kit part Number 017057 that would retrofit the design used previously.

Performance data with the 017057 Jake on an 8V92 was:
1100 RPM 110 Retarding HP
1300 RPM 135 Retarding HP
1500 RPM 170 Retarding HP
1700 RPM 185 Retarding HP
1900 RPM 230 Retarding HP
2100 RPM 260 Retarding HP

[Wally Arntzen]

I have a 1988 with an 8v92 and my jake works on all 8 cylinders and really does a job, especially in the mountains

[2dogs]

Thanks mike for the info. I was thinking that because there was only one wire, the purple one going to the back. that the factory for safety reasons did not include high. hence just on/off.

Brian