so i finally got my car up and running on a set of itb's. the car runs great just need to adjust a few minor things. but what i found is that the brakes suck. and im 99% sure its due to my vac manifold setup

currently running a golden eagle vac manifold.

will setting up a larger vac manifold solve this? i know itb's are notorious for very low vacuum and lots of fluctuation, so im not sure if a larger can would help the issue? but ive seen so many different setups, i know someone must have itbs with normally functioning brakes.

thanks for the help.

 

You can either create a larger vacuum chamber to store up more of it or you can do what 2point6 did and get an electric vacuum pump.

I've also heard of people using C5 'vette electric smog pumps to get a vacuum.

 

or get another GE log for the brakes only

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PirateMcFred &raquo;</TD></TR><TR><TD CLASS="quote">You can either create a larger vacuum chamber to store up more of it or you can do what 2point6 did and get an electric vacuum pump.

I've also heard of people using C5 'vette electric smog pumps to get a vacuum.</TD></TR></TABLE>

i figured that was the answer. for a second when i thought about it it just didt seem to make sense that it would work since the vac is so low.

ill have to find time to try it.

 

At cruise and part throttle you should be pulling about 500mbar pressure or less. That should be plenty of vacuum for the brakes. The larger vacuum reservoir should "charge" while you cruise at part throttle and should have a check valve to keep the vacuum contained when you're at idle or WOT.

I have some big nonVTEC cams and the lack of vacuum had me concerned that my brakes would not work at the track. Despite all the WOT there's enough part throttle and engine braking that it pulls plenty of vacuum when not on the gas. Brakes work fine.

 

where are you running a check valve?

i might try sticking a check valve in each line from throttle runner to the vac manifold maybe? atleast that would let me kwwp what i have?

i mean my brakes work, but only stos at like 60-70% of what i think the potential should be

 

Yes you need a check valve between the runners of the TBs and the vac log to maintian the accumulated vacuum for your brakes.

Mind you, depending on your setup, you should NOT put your MAP sensor on the same vac log. lol

What are your minimum MAP pressures you're running?

 

i havent looked at the map pressures, my computer has decided to not like neptune anymore, so i wont know till i go for my tune friday.

as of now the map is on that manifold, thats why i was more leaning towards the bigger manifold...although i probably have the check valves laying aorund so i may try and see what happens.

 

Try the valves. Then if that's not good enough try a larger reservoir.

 

a one way valve shouldnt effect the map readings right? if anything help maybe because it will see more constant pressures?

 

My car idles at around 95kpa, the power brakes were none existent, switched over to a Wilwood master and its allot better than before.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PirateMcFred &raquo;</TD></TR><TR><TD CLASS="quote">You can either create a larger vacuum chamber to store up more of it or you can do what 2point6 did and get an electric vacuum pump.

I've also heard of people using C5 'vette electric smog pumps to get a vacuum.</TD></TR></TABLE> The AIR or EGR pump?

I have a spare AIR pump and some free time &gt;_&gt;