SCREAMIN01SS

When installing an ATI prochrger, exactly where did you install the hose that goes from your purge valve to? the directions say hook it up to a vacuum source. I did that and when the car in in neutral and being revved i can see the valve open and close but when driving around i dont think it is opening and closing correctly because it does't make a purge sound after you let off but a weird muffling type sound and the boost gauge bounces around instead of a sudden drop in boost like it is purging through the blower itself...any ideas?

SCREAMIN01SS

I was just doing some research in my manual and it ays under high rpm decelerations, minor compressor surge (a fluttering sound) can be heard and this is normal. This is exactly what i was talking about but it is pretty loud and im still a little bit concerned about my boost gauge bouncig....i gues im just worried about a compressor surge...what is everyone else's experience with it?

ItsNotStock

iTrader: (24)

What source did you hook it up to? That could be your problem. An inadequate source can lead to surge. But you also have to remember that the ATI unit is a BPV and does not operate exactly like a BOV. Either way I would get it taken care of soon as you could damage the head unit.

SCREAMIN01SS

i hooked up up to the passenger valve cover breather just like the manual said to. I am just looking for first hand experience from someone who has the same setup I do. This is not my daily driver and only gets driver like once a month for a few minutes. Also could you clarify what you are talking about the difference between a BPV and BOV are. ATI describes it as an anit-surge valve... thanks for the input

dlandsvZ28

My ATI manual was printed in 2005 for a D1SC. Later editions might be different.

The vacuum source with pictures is displayed and explained on page 39 Section K.

It's unlikely the vacuum source that ATI suggests to use will be defective. You can suck on the vacumm line attached to the ByPass value with someone looking at the ByPass valve too see if it opens or not.

You might or might not hear the valve open and vent if you are venting to atmosphere. If you are not venting to atmosphere then I don't think you will hear it purge as it circulates back into the plastic inlet hat isolating the noise when it vents.

In 05 ATI supplied a very cheap plastic ByPass valve. I never heard it vent. I replaced it with the newer style black ByPass value with a small K&N filter. I can sometimes hear it vent - sometimes not.

The screws fell out of the original plastic valve locking it in the open position. I replaced the screws and used red threadlocker on them so they wouldn't vibrate loose. After that espisode I replaced it with the newer style ATI ByPass valve not trusting the use of possible cheap parts inside the valve as well.

ItsNotStock

iTrader: (24)

Haha, I was thinking he meant the big red-Not the stocker one. Makes a little bit more sense that he can't hear it now. I have heard the race version and you have to be deaf to miss it. The only reason I thought it might be an inadequate reference is a poor reference point can lead to lag in opening and closing.

How much boost are you running?

SCREAMIN01SS

in my manual, the instructions are in section "L" not "K". Not that it makes a difference. I put in the blower last summer and the bypass valve (surge) is black. Like I said, when i tested it while the car was in nutrel, (with me laying under the car and my friend reving the engine) I could see the valve opening and closing I was just concerned about the "fluttering sound" the manual describes...i gues i was expecting a quick sound similiar to a tire when you let the air out through the valve stem not a slower fluttering sound. if this is what you all are experiencing, then great I just want to make sure. I am suppose to be running 8psi of boost but the gauge only peaks at like 5psi, i think my blower pulley is too big for my altitude but thats another issue, i can't seem to find a vacuum source for my mechanical boost gauge that I am comfortable with. I have tried all soucres from LS1Tech but don't geat great readings- t-fitting off back of intake gave me only vacuum and would only show like 1psi at full boost, brake boost line wasn't much better, i even tried to hook up my line to the throttle body where the ATI manual has you remove the tube that connects it to the passenger valve cover breather and place a plastic cover over on page 41. it actually seems to be the best source but concerns me during deceleration becasuse the gauge "flutters" what do you all think about tapping directly into the plenum--i'm thinking that would be the most accurate source...open to any thoughts
thanks again