Exhaust Brake-Anyone built their own?

[cdennyb]

nothin special to report

Well, the ride down south was uneventful. (just like we like it!) I loaded up a full bedroom set, cal king size mattress, box spring, frame, dresser, 2-night stands, and a chest of 4 drawers. Not much weight and tarped it good. (It was supposed to rain on and off and I figured I'd rather tarp it before it started raining.
The trailer was my old 30' flat bed, weighin in at around 1800# plus load. I used the brake on and off the whole trip and had no problems. The finished numbers are this:
loaded at 60 mph, cruising, back pressure (BP) was around .4 psi. With the brake applied fully it started at 11 psi and slowly dropped as the rpm dropped until at 40 MPH the convertor unlocked and the idle dropped to 800 rpm, If I engaged the brake and took it out of overdrive, forcing the convertor to stay locked as it slowed down, at 2800 rpm at 50 or so it was a high of 14 psi and dropped from there as the rpm dropped off. I hope these numbers are of some value to anyone who wondered.
The total area reduction is around 92.4%. I figured the pipe was flowing around 570-580 cfm before the blade closed and then of course the same flow was being forced through the equivelent of a .4 sq inch hole. That's some kinda reduction in flow area.

 

[cdennyb]

finished product done

I finally got it all done. It works perfectly. Warm up in the morning will last about 18-20 minutes before the air supply is exhausted...but the second the boost goes back up the tank recharges. I did weld in a quick disconnect joint, and the sealing rings to get a better backpressure reading. Any questions?

 

[rubberfish]

Any questions?

Yup,,,,,2 of them.

When do they go into production?
And how much are they?

 

[cdennyb]

like I said in a previous post, I'm busier than a one legged man in an a$$ kickin contest! I just don't have time to build 'em, but...
I'll give you what I have in knowledge and research and help you build your own.
Maybe I could put together a parts list and source sheet and get it out. I'm into this little critter for about $175.00 in parts. best I can do...sorry.
Don't be scared, you can do it.

 

[holtzer1]

one question....what does it sound like at the tailpipe when kicked in? so far every cummins i heard with an exaust brake had a muffler...so all it sounded like was a huge vacuum leak coasting by.

 

[cdennyb]

yep, just sounds like the exhaust is muffled and makes a big hissing sound. not the traditional "jake brake" sound like the NTC series make but it does slow you downand that's what it's all about.

 

[Whit]

I would be interested in a parts list, this could be a fun project, I need an inline anyway so I can get a different turbo and rid the Jacobs hooked to it now

Thanks fer all the R&D so far

 

[holtzer1]

yep, just sounds like the exhaust is muffled and makes a big hissing sound. not the traditional "jake brake" sound like the NTC series make but it does slow you downand that's what it's all about.

damn...i wish theyde come out with a real world jake brake...that would sound so damn cool on a cummins...just close your eyes and imagine you driving through town loaded with a trailer...hit the ol jake brake switch on the straight pipe....mmmmm, (wiping up drool)

 

[Mopar1973Man]

damn...i wish theyde come out with a real world jake brake...that would sound so damn cool on a cummins...just close your eyes and imagine you driving through town loaded with a trailer...hit the ol jake brake switch on the straight pipe....mmmmm, (wiping up drool)

Stop it! You got me doing it too... (Droolin')

Now I like the exhaust brake idea... It looks like it would be better than the Jacobs Brake I've got now... But the air idea will not work for me... I've got mountain roads to come down with a full load of firewood and I might not see boost for over an hour! 35 miles of rough road traveling at about 10-15 MPH and jakin' the whole way down...

So I would have to reverse it back to a vacuum system.

Cool anyways!

 

[cdennyb]

jake brake, you bet!

I'm all for the jake brake thing. I love the sound, (in moderation!) since I was an owner/operator for 8 years. But the problem you have, lots of downhill is a consideration. If you use a push-pull type of air cylinder (Bimba type) then you can pull the blade shut with vac on the opposite side. You can get vacuum from the air control pump if you'd like or add another small vac pump. That woulod be alittle more expensive. I don't have an hour of downhill anywhere I live so it wasn't a consideration. I do have my brake operational since I'm the one who started this thread long ago and it's working perfectly. I had a small situation once about 3 months ago when the 1/4" plastic air line got a little too close to a moving bracket and got a hole rubbed in it. Other than that, no issues, yet.

Good luck onconvincing Jacobs Mfg to build (all of us) a jake brake for the ISB cummins in our dodge trucks! Sign me up for one.

db

 

[rubberfish]

Sign me up for one too. They'd have to make
them available for all generations, or
there'll be rioting in the streets over this.

 

[Mopar1973Man]

I got to admit the design is very clean and simple... I wish I had the materials and the tools to do such myself... Using your idea you could build any sized exhaust brake you wanted... 3", 4", or even 5" pipe!

Now you got me thinking of future plans of 4" exhaust and a in-line exhaust brake... Hmmm... Sounding really good now!