Pac Brake or Jacobs Brake pricing info
11-19-2009 | 01:18 PM
#16
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Joined: May 2004
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From: Caistor Centre, ON, Canada
What you consider falling short I consider a positive. I like that the braking pressure decreases with rpm, I find it much easier (in theory) to control speed when i can pick retarding hp. These brakes are very effective and quite often I upshift to reduce psi to get the braking I need.. I don't think (in theory) I could do that as well with the PXRB. i.e if I put in in 6th at 65 mph I am at 1875 rpms, which is about 50psi and I hold the speed. If I need more braking then I downshift to 5th and am at 2575 rpms and have 60psi. But more often than not 6th will be the correct amount of braking and the brake doesn't cycle as often (which I prefer)... The PXRB will have 17% more retarding pressure at 65 in 6th and the brake will have to cycle much more often..
So it comes down to brake cycling, I prefer mine not to cycle all the time.
So it comes down to brake cycling, I prefer mine not to cycle all the time.
I agree, and I don't not have an argument or explanation for one brake generating more peak retarding power over another if we can assume they all hold a max of 60 psi of back pressure. Average retarding power is a very different story...which I happen to think is more important.
11-19-2009 | 02:40 PM
#17
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Joined: Nov 2007
Posts: 4,737
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From: Kuna, Idaho
This is your theory that I'm taking as conjecture. It does not play out in practice how you have theorized it. You obviously need to drive a truck with a PRXB. After owning and driving trucks with a standard Pac, Jake and PRXB, I'll take the PRXB hands down. There is no additional cycling of the brake, either.
I agree, and I don't not have an argument or explanation for one brake generating more peak retarding power over another if we can assume they all hold a max of 60 psi of back pressure. Average retarding power is a very different story...which I happen to think is more important.
I will say that on an auto truck I would take the PXRB, but on a manual where I can always get my rpms to 2500-3200 I will stick with the Jake... just my .02 (thats whey we love America)
11-19-2009 | 03:15 PM
#18
Chapter President
Joined: May 2004
Posts: 3,539
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From: Caistor Centre, ON, Canada
Ahh....I'm understanding more about what you mean by the brake cycling. The PRXB has a small internal blow off valve in the large, main butterfly valve that does all of the regulating. The large valve does not budge when regulating the pressure - it is either open or closed. The small blow off valve is designed to react fast and work rapidly and has nothing to do with the main valve operation. The small blow off valve is certainly time proven to work well and be very durable. There are a lot of PRXB's out there and you hear very little complaints about them.
11-19-2009 | 03:19 PM
#19
Chapter President
Joined: May 2004
Posts: 3,539
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From: Caistor Centre, ON, Canada
And all I'm saying is that you don't have to rev that high to do the same thing with a PRXB. When I am empty, I engage at 2500 rpm and slow down from there. When I don't have to slow down in a hurry, I can engage a 2000 rpm and slow down from there and down shift at around 1600 rpm. There is no need to rev higher....all the braking power you need occurs earlier.
11-19-2009 | 03:25 PM
#20
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Joined: Nov 2007
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From: Kuna, Idaho
Ahh....I'm understanding more about what you mean by the brake cycling. The PRXB has a small internal blow off valve in the large, main butterfly valve that does all of the regulating. The large valve does not budge when regulating the pressure - it is either open or closed. The small blow off valve is designed to react fast and work rapidly and has nothing to do with the main valve operation. The small blow off valve is certainly time proven to work well and be very durable. There are a lot of PRXB's out there and you hear very little complaints about them.
And all I'm saying is that you don't have to rev that high to do the same thing with a PRXB. When I am empty, I engage at 2500 rpm and slow down from there. When I don't have to slow down in a hurry, I can engage a 2000 rpm and slow down from there and down shift at around 1600 rpm. There is no need to rev higher....all the braking power you need occurs earlier.
11-19-2009 | 03:49 PM
#21
Chapter President
Joined: May 2004
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From: Caistor Centre, ON, Canada
I run the brake manually on the shifter switch.
11-19-2009 | 04:57 PM
#22
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Joined: Oct 2002
Posts: 425
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From: Spruce Grove Alberta
Jim O
11-19-2009 | 05:13 PM
#23
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Joined: Oct 2006
Posts: 751
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From: Mesa AZ
Well when I was looking to put an EB on I too did alot of research and talked with people that had both. As always evryone has the fav. I ended up finding a shop in town that does both and nothing really good to say about Banks(ok over engineered and 8hr install) or B&D(really nothing good) as they also install all 4 as well. They said there were more come backs with Jac but not major not enough to quit selling them. For the Pac that was there top seller/install. He said 1000+ installed over many years(Pac/PBXR) they have had only 2 come back, air ram failer or compressor. Good thing about that is if it does fail it fail safe(open) Now he said on the Jac on the few that it was the vac pump that quit so carry a factory belt just in case.
So after that I decided to go with the Pac and its works perfect for me.
So after that I decided to go with the Pac and its works perfect for me.
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