I did not want to hijack someone elses thread but there has been a few articles lately about brakes, issues etc and I wanted to add something. After I installed my 2016 LT Chev engine they do not have vacuum on the engine due to the cylinder deactivation feature (which I deleted in software) but they come with an engine driven, oil lubricated vacuum pump for brakes. With this system on line to my booster the braking of my JK with stock brakes and CC pads is absolutely perfect. I can even use the brake pedal up and down as often as I want and there is no loss of efficiency. They are good to the point that I was contemplating a BB kit now deemed no longer necessary. To my fellow Jeepers I suggest finding a better vacuum pump and having more vacuum on the booster as opposed to going with bigger discs expense. Pads are at about 50,000kms and are starting to show wear but they are just a maintenance item anyway. Even high speed freeway oh shit stops are achieveable now. Just thought this might help.

 

I don't disagree with that idea at all, but it kinda seems like maybe one of those easier said than done things. I've been under the impression that the pump is only really working when the variable timing isn't producing enough engine vacuum. Am I wrong or is that operating 100% of the time? If it is only working part of the time, then how would you get that to be on all the time to make use of it? Also, I presume that would require knowing what kinda vacuum this pump is creating and then finding some other alternative that is capable of producing more vacuum and then wiring that in instead? On a side note, I really had no clue that OEM pump costs so much -

 

look into hyroboost. It will be the best you can do. Runs off the power steering system.

 

Resharp - yes there is vacuum when running on 8 cyls but the vac lines run only from the pump. Not sure of the internal cutoffs but it is on 100% with engine running. It is about the same size as a smaller AC compressor and bolts to oil ports on the block. I agree it may take a bit of investigating to see if this excercise is worthwhile as one has to find a better more suitable electric pump. Price of Mopar part

Dirtman - I agree with you as well as I had hydraboost from a GM van on my 73/451/610HP Challenger and used Cordoba front discs and Viper calipers. That thing would stop. Folks the hydraboost units are like $20 at a Pick N Pull yard. There is quite a bit of work to make them function but they delete the brake booster completely.

 

is there something on the back of the intake manifold that looks like they cast it with the idea of adding a hose to it?
I'm only familiar with the LS, but the original intake from my LS (Gen4) has it in the back.
The block I used has the AFM towers, but it's not drilled out for the deactivation feature (factory GM 6.0 bare block, got a great deal on it in 2020).

 

I don't think that was there when I had the manifold off. Back end was pretty flat on the vertical side. Its just there is no/low vacuum when the engine is in 4cyl mode which pulls way better in V4 than the LS and stays longer under load. But I disconnected mine in HPTuners by simply selecting "disabled".