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Engine/Transmission (1998.5 - 2002) Sentinel exhaust brake

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Engine/Transmission (1998.5 - 2002) More exhaust sound

This looks to be a fixed orifice design similar to the early Pacbrake design (no calibrated spring loaded valve to cover the orifice at low engine rpm). The later Pacbrake PRXB design uses this valve and has far more effective braking power at lower engine rpm, clear down to a 1,000 rpm.

I ran the early design Pacbrake for over 400,000 miles and it was still operating as it should when I replaced it with an in-line PRXB. The PRXB has so much better braking power below 2,000 rpm - so much better that I can use one gear higher driving down grades than I did with the earlier design.

- John

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This looks to be a fixed orifice design similar to the early Pacbrake design (no calibrated spring loaded valve to cover the orifice at low engine rpm). The later Pacbrake PRXB design uses this valve and has far more effective braking power at lower engine rpm, clear down to a 1,000 rpm.

I ran the early design Pacbrake for over 400,000 miles and it was still operating as it should when I replaced it with an in-line PRXB. The PRXB has so much better braking power below 2,000 rpm - so much better that I can use one gear higher driving down grades than I did with the earlier design.

- John

View attachment 143114

View attachment 143115

Thanks for the reply . Would you go with an inline design or a turbo mount design if you did it again ?
 
Would you go with an inline design or a turbo mount design if you did it again ?

As far as performance, I could go either way, but I am basing this on the installation on my OEM 3" exhaust system. With a 3" inch exhaust I don't think the location of the exhaust brake plays that large of a role in performance because the additional air volume is much less than say, a 4" exhaust system. Just my opinion here.

I do like the in-line exhaust brake as it is quieter than my previous direct mount. I think this may because it is farther downstream than the direct mount, so the additional quantity of compressed air may muffle some of the harshness.

In my situation (3" exhaust system), the direct mount 4" exhaust brake would have been a much easier installation and no welding would have been required. The in-line exhaust brake (4" diameter) had to be adapted to the 3" exhaust system - definitely more work, however, in the end - well worth it.

Another thought that is in favor of the in-line exhaust brake is that the air cylinder is in a much better ambient temperature location - the seals will likely last longer - and, if they do fail - much easier to change out the cylinder.

- John

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Direct mount. Less points to leak, faster reaction, save from the environments. Proven good by millions and millions of vehicles.
 
Direct mount. Less points to leak, faster reaction, save from the environments. Proven good by millions and millions of vehicles.

I had a direct mount on my 93.5 I realy liked it . I honestly didn’t know a inline was a thing . I do like the inline idea for ease of mounting . Myself I like the noise almost sounds like a Jake brake kinda :):)
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As far as performance, I could go either way, but I am basing this on the installation on my OEM 3" exhaust system. With a 3" inch exhaust I don't think the location of the exhaust brake plays that large of a role in performance because the additional air volume is much less than say, a 4" exhaust system. Just my opinion here.

I do like the in-line exhaust brake as it is quieter than my previous direct mount. I think this may because it is farther downstream than the direct mount, so the additional quantity of compressed air may muffle some of the harshness.

In my situation (3" exhaust system), the direct mount 4" exhaust brake would have been a much easier installation and no welding would have been required. The in-line exhaust brake (4" diameter) had to be adapted to the 3" exhaust system - definitely more work, however, in the end - well worth it.

Another thought that is in favor of the in-line exhaust brake is that the air cylinder is in a much better ambient temperature location - the seals will likely last longer - and, if they do fail - much easier to change out the cylinder.

- John

View attachment 143117

that looks like a nice unit
 
Inline has more air to compress, which makes the time to effective braking slower. You also have a larger volume of air to release, which can be louder depending on your muffler situation.
 
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