EXHAUST BRAKE COMPARISON

[DTanklage]

wish this woulda been a sticky bout 3.5 months ago:

these are both supposed to be 4" inline brakes

4" PAC PRXB above and 4" BD below



as you can see the prxb is tiny compared to the bd. (approx 3.5", but then you have to subtract out the area of the shaft, plate, pressure relief, and the actuator arm for the press relief)

DO NOT ORDER A PAC 4" BRAKE IF YOU ARE LOOKING FOR A FREE FLOWING EXHAUST SYSTEM

[ford69557ci]

i want a 6" brake wtf makes one of those?

[DTanklage]

PAC BRAKE SUCKS

[flashgordon]

PAC BRAKE SUCKS

Mine is a Jacobson ext brake, activated by a "delay relay" and vac form
Your vac pump. have allso found out that my'n is for a 2nt gen,
and it works grate. if you are not pulling a load down a steep hill you my not realize the holding power.
Mine didn't impress me at all, untell i was hauling my Cuda to the races and headed down parleys canyon I became a believer

Flash.

[DTanklage]

the purpose of this thread is to worn others (that are into high hp ve trucks) not to get sucked into buying a pac brake

they have two models - one that stops great but doesnt flow for sthi

and one that flows real nice but doesnt brake well (like i am gonna spend a grand on a brake that doesnt brake!)

what is the id on your jacobs?

[CAJUN 93]

well, my turbo mounted pac brake doesn't seem to suck at all. i'de say that after 3 years of maintenance free use, it has worked pretty good. now i'm not saying it flows really well, but its turbo mounted and its the same size as the outlet on my 16cm housing. keep in mind my truck is more tow oreinted than some of the hot rods on here. my wifes truck is the toy and it has no exhaust brake. i dont know why a toy needs a brake and why on a work truck exhaust restriction is that big a deal. maybe your asking too much of one vehicle.

daryl

[flashgordon]

well, my turbo mounted pac brake doesn't seem to suck at all. i'de say that after 3 years of maintenance free use, it has worked pretty good. now i'm not saying it flows really well, but its turbo mounted and its the same size as the outlet on my 16cm housing. keep in mind my truck is more tow oreinted than some of the hot rods on here. my wifes truck is the toy and it has no exhaust brake. i dont know why a toy needs a brake and why on a work truck exhaust restriction is that big a deal. maybe your asking too much of one vehicle.

daryl

mine is a different brand but is a 3" elbow that v clamp to the outlet of the turbo and has a large butter fly valve with a designed hole drill in the flapper valve so that the valve can be close completely.
Mine too, is more of a puller then a play toy........but its still fun to play with

If you have a 4" down pipe this could be a little bit restrictive.

Flash.

[DTanklage]

i dont know why exhaust restriction is that big a deal on a work truck.

maybe your asking too much

well, if you dont understand when fuel is almost 4 bucks a gallon i dont think you are ever gonna understand.

"asking too much?"

dude, i spent $1,000.00 (plus shipping) on a 4" ex brake.

it is not 4"

who's fault is that?

[CAJUN 93]

kinda took me out of context there. you must have some politician in you somehwere.

i didnt see anything in your pac brake bashing about fuel mileage considerations. i guess my mind reading is limited with your capacity. i dont know but i would think fuel mileage will be affected very little on a tow oriented rig with the smaller brake. i concede your point, if it says its 4" then it should be 4". maybe its like exhaust pipe. theres a difference in 4" id and 4" od. maybe thats where the difference lies.

nowhere did i say you are expecting too much of your $1k brake. i said you maybe expecting to much of your dual purpose truck.

kinda touchy, aint ya?
daryl

[DTanklage]

touchy? me? lol. you would be touchy too if you had been driving around with nothing but a down pipe on truck for the last 3 months

"call back next week", "call back next week"

tubing is always measured on the od

pipe is always measured on the id

when you hear ex guys refer to i.d/o.d. they are talking about the ends of a pc of tubing or u-bend

[Begle1]

By "4 inch exhaust brake", they mean "an exhaust brake that will fit a 4-inch exhaust system just fine". And the unit is an exhaust unit that will fit a 4-inch exhaust system just fine, as is evidenced by the hundreds of guys out there with them on their 4-inch exhausts.

It's obviously a restriction, and now I know to recommend the BD over the Pacbrake, but I don't think I'd go as far as to call it false advertising. I don't think you're ever going to see that much of a difference either. It's probably less of a restriction than the pyro probe...

[ford69557ci]

i wish someone would make a 5" that works good cuz i would still like to tow my boat around and i get tired of ridin the brakes down the big ass hills. i have the pac brake that was bolted to my cat turbo when i got it and it is 3 3/4" id but i called pac several months ago about it and the said my calipers must have been wrong.dee dee dee.

[DTanklage]

It's probably less of a restriction than the pyro probe...

uhhhh NO

[DTanklage]

It's probably less of a restriction than the pyro probe...

uhhhh NO

ps - i didnt spend fregin $300 bucks modifying PDR's pos $250 down pipe (that you can now 3.900" roll a ball thru) so i could spend another thousand bux on a 4" brake that is really smaller than 3.5"

pps - aaron, that is why they told you your calipers were broke, cuz it aint even 3.75"

lol

jk - i have no idea what model brake you have

mine is the supposed 4" PressureRegulatedExaustBrake model

[CAJUN 93]

touchy? me? lol. you would be touchy too if you had been driving around with nothing but a down pipe on truck for the last 3 months

"call back next week", "call back next week"

tubing is always measured on the od

pipe is always measured on the id

when you hear ex guys refer to i.d/o.d. they are talking about the ends of a pc of tubing or u-bend

yeah, i could see where that would affect my attitude . i've been on the phone with pacbrake a couple times and havent had any problems but i can see where your situation would tee me off.

on the id od thing, i've ordered pieces of pipe and bends and such from the walker catalog at my wifes work and i thought i remember id and od on everything but i may be wrong (hey, its happened before )

daryl