Drive pressure and exhaust brake(vgt)

G

G1625S

New member
Joined
Aug 14, 2009
Messages
340
I finally got a manual control on the shifter for the e-brake function on the vgt. I'm using the spring control method with a stock governo spring setting the start point and a cable pulling against the gov spring via a t-handle on the shifter. Works awesome, but....3rd gear downhill, 2200 (running empty), pull the handle and my 60psi drive pressure gauge is pegged:doh: Gonna pop a 100psi gauge in tomorrow, but the question is, how much is too much drive pressure in e-brake mode? I see about 40psi drive for 35psi boost when gettin on the throttle and the springs regulate it there pretty good. I saw a video of a 6.7 and it was all he could do to hit 60psi of drive under loaded e-braking....this thing definitely works awesome and sounds very 'real' jake like through the intake, but I might put a limit on the pull cable pending the advice given here.
Thanks!
greg
 
My BD brake hits mid 50s fairly easily. It wouldn't scare me if I saw 60psi. $.02
 
yup, got the valve springs. It brakes really well over 55psi drive, just don't want to push my luck....on edit, when I was dialing in the vgt spring setup, I pegged the dp gauge several times before I got soft enough springs.
 
I'll try and get some video tomorrow, my phone was acting up tonight. The cool thing is, I left enough slack in the cable in order to allow the vanes to open as far as they want under drive pressure. I can hold the t-handle and 'feel' the dp pull the vanes open. I can also hold the handle and control the vanes manually. The dp/vs/boost/vs/egt is not what I would have expected....
 
I'm pretty sure pac brake told me they set there's to 60psi. Make sure you are using a liquid filled gauge. Unless the vgt is different, when I was testing with the gauge off my air compressor it would bounce up to 100psi. With a liquid filled gauge it would stay at or under 60psi.
 
Huh, that's interesting. I'm just using a regular 0-60psi boost gauge right now. It 'seems' pretty sccurate when driving, but who knows. Think I've got a liquid filled somewhere in the shop.
 
G1625S said:
Huh, that's interesting. I'm just using a regular 0-60psi boost gauge right now. It 'seems' pretty sccurate when driving, but who knows. Think I've got a liquid filled somewhere in the shop.
Click to expand...

The gauge I was using was off of a craftsman air compressor and I'm sure it was as cheap as they come. If the needle on your gauge isn't bounceing around its probably fine. Mine would bounce in about a 40psi range.
 
You must log in or register to reply here.
Back
Top