Pacbrake PRXB?

[Winston Wolf]

I've been thinking of an exhaust brake for my 3G for awhile and have seen a few comments about there not being much braking power available w/o high RPMs.



Now I notice a new e-brake from Pac called a "Premium Performance Exhaust Brake", or PRXB. See:

http://pacbrake.chargedmultimedia.com/products.php?item=Exhaust_Brakes/PRXB//Information.html



The way I read it, this new design provides more braking power at mid-RPMs.



But... don't see an app listed for our beloved Ram+Cummins.



Anyone know if Pac is working on a version for us?



Thanks.

 

[Doubleclutch]

Last time I talked to them, they were to release after Christmas... might have to call again. Sounds pretty trick, and I'm also interested. If you call before I do, please post the results, I'm sure there are others who've been wondering.

Greg

 

[TCDiesel]

It will not be available until after spring. Who knowns Maybe summer. I too was wanting the New PRXB . Last Fall I was willing to wait. I just order the direct mount with Ecm bypass and Auxiliary tank.

 

[Winston Wolf]

Call to PacBrake

Okay, I did call the toll-free line.



PacMan said "Late this spring. " "It will replace the current brake". "Much better braking at mid-RPMs. " And "Cost will be slightly higher. Maybe $100 or so. "



I think I gotta wait for it.

 

[Winston Wolf]

It will not be available until after spring. Who knowns Maybe summer. I too was wanting the New PRXB . Last Fall I was willing to wait. I just order the direct mount with Ecm bypass and Auxiliary tank.

TWest... not sure I get what the ECM bypass thing is all about. Further comments appreciated.

 

[Doubleclutch]

WW- It's probably installing an "old style" throttle switch instead of tapping into the ECM throttle input to turn on the brake. I'm guessing, but either way works. (brake needs to "know" when throttle is off before engaging)

Greg

 

[TCDiesel]

No delay with Ecm Bypass. If you have a stock trans the Ecm Bypass may Not be a good Idea ,Also the Rail Does may not drop pressure. Pac has had no claims of rail problems with the Bypass.

 

[sangell]

TWest,

When you get your kit, read the Installation Procedures for the Optional ECM by-pass Mechanical Wiring. First paragraph, ninth line. I qoute "Under no circumstances should both systems (ECM By-pass and Air Tank) be installed, engine damage will result. " The reason for this is the air tank and ecm by-pass do the same thing, quicker brake activation, just with a different method. When using both systems the rail does not have time to clear. I went with the air tank on mine.



Scott

 

[Piers]

I have one of the new Pac brakes on my 04. 5, we are just beginning a series of tests for Pac. Once we finish they'll be ready to go... unless your like Fred at Desert Diesel, then you can have one early and do your own testing. We do have 10 of these brakes in a 5" configuration, for the guys with twins or big exhaust, that were used for two hours each in testing, these we'll be able to sell at a discount because they are slightly used. Although I feel they are better than new... . they have been tested

 

[SRadke]

Was there a noticeable diffrence in your testing? I have an old style 4" inline and I'm thinking about twins so I'm trying to decide to keep it or just step up to the 5". Thanks



-Scott

 

[Fred Swanson]

Scott, if your going to twins, you will want the 5 inch brake. Thanks Piers, I almost beat you getting one on, but thanks to you I have one on the way.

The PRXB(Pressure Release Exhaust brake) will be available for the 04. 5 models as a direct mount, no word that they will make one for the earlier models. There is a 4 inch and a 5 inch inline that will be available.



If mine shows up by Friday, I'll have it on this weekend for some comparison's to the 4 inch inline original design pac I took off.



The info on it states less downshifting required, as it will maximize engine braking even at lower RPM's. This I have to see for myself.

 

[SRadke]

Thanks for the info Fred, I look forward to your comparative comments.



-Scott

 

[TCDiesel]

TWest,

When you get your kit, read the Installation Procedures for the Optional ECM by-pass Mechanical Wiring. First paragraph, ninth line. I qoute "Under no circumstances should both systems (ECM By-pass and Air Tank) be installed, engine damage will result. " The reason for this is the air tank and ecm by-pass do the same thing, quicker brake activation, just with a different method. When using both systems the rail does not have time to clear. I went with the air tank on mine.



Scott

Yeah , I saw it ,Pac May update that,Quote. That was a comment from a outside source of a potential problem that never has develop. Thanks for heads up.

 

[TCDiesel]

last Fall I did a test drive in a 8. 3 . it had the PRXB installed ,It"s differently better ,no matter what RPM"s are . It was a Eaton 8 speed automatic which I did not care for. I talk to many companys about a engine Brake for the 5. 9 . All made the same statement less than 8. 0L is just to small,the Exhaust brake will get you the same benefit.

 

[SRadke]

I was thinking about this last night..... I know, I could have really hurt myself! Here's my question.



I assume this pressure release brake has some sort of mechanism and spring in it designed to vary the amount of gasses it allows to escape thereby maintaining a constant backpressure (60psi?)... ... . does that mean it will be more forgiveing of exhaust leaks in front of it? I fought my current 4" for a while to get the downpipe sealed up and with this unit available in 5" for twins I expect an even greater possibility for leaks.



-Scott

 

[Fred Swanson]

Here's a couple of shots of the new PRXB 5 inch inline.

Brake w/adapter ring to allow it to fit a normal 5 inch lip flare.

#ad




Brake looking at the internal release mechanism

#ad




Kit with mounting group. Notice the smaller looking lip flare, that's a 4 inch flare. The brake air cylinder is twice the size of the 4 inch inline one.

#ad

 

[Gypsyman]

Thanks Fred! Really appreciate you taking the time to post those. That's the first pictures I've seen other than the brochures.



Richard

 

[Fred Swanson]

If all goes well I should have it on later today.

 

[Doubleclutch]

Fred- The center picture is showing a dangly part sticking into the exhaust flow, behind the butterfly valve. How does that feedback to the spring mechanism?

Greg

 

[Fred Swanson]

Greg, that is the pressure release level that strikes a plate on the butterfly that is also spring loaded, and it opens it slightly to keep pressure at peak and not go above.

I have it mounted now, but need to adjust it. Not getting enough back pressure yet, and I can tell when the pressure release hits. With a permanent drive pressure gauge, it works as a back pressure gauge when out of the throttle.

The release is also spring loaded, so you can adjust the effect of the release, it's just getting everything setup right.



I'm going to adjust it tomorrow.