AVCR and vacume help PLEASE!!

[koukiKA240]

Im at that point in my install when i need to figure out all the vacume lines. I have a 91 240 but im using a 95 manifold. So i guess my question is to the s14 guys with AVC-Rs. I dont even know where to start. Ive wired it up and it turns on. ive got the harness through the firewall but i cant seem to follow the instructions too well. What vacume lines did u tap for each regulator for the avcr. What about the wastegate, and BOV (if it needs vacume). Is there anything i have left out? Thanks in advance.~Sam

[daniel240]

i just finished helping my friend install his avcr in his mr2 a few hours ago. you need to tap into the wastegate line and a vac line from the intake man. the fpr vac line will work.

[koukiKA240]

In the diagram in the instruction manual it shows that i need a vacume line that goes from somewhere on the charged end of the turbo before the TB to the bottom of my wastegate. And i need to tap that line to go to one side of the solenoid then the other side goes to the top of the wastegate. What line can i tap? Can i use the fpr line?? Is that one that gets its air from before the TB? Im really confused at this point with the whole vacume line ordeal. Any help is appreciated.~Sam

[WDRacing]

The way it should work, bare with me I've never installed one, is to have a vac signal from the manifold go to the AVCR solenoid, then from the solenoid to the wastgate. This is so the AVCR can tell the wastegate when to open.

Here's my theory on vacuum, for wastegates, I always use a vac source from the intake plenum somewhere. I usually install my own bung of some type, but the FPR line will work for most everything. The reason I suggest using a source from the manifold is that you don't have to worry about any pressure drop from IC piping or intercooler restriction. So your your boost gauge shows exactly what PSI your motor is ingesting, assuming your gauge is also on the intake mani side.

Most turbo's have a threaded hole on the compressor for a fitting to go for a wastegate signal. I don't ever use that.

Long story short, yes, just use the FPR line for your vac signal. If you need to get mutiple signals, use a muti tap T-fitting, don't use a bunch of single taps.

Hope that helped some.

[koukiKA240]

The instructions show that the wastegate should already have a vacume line from the center part of the wastegate to the manifold after the TB. It then says to T into that line and connect to one side of the solenoid. From the other side of the solenoid connect a vacume line from the solenoid to the top off the wastegate. There is a seperate pressure sensor that the instructions say to install with a T on the FPR line. The guru of cars who has been a great help for me belives that the solenoid would need the reading before the TB as the instructions illustrate but i have NEVER seen a setup like that.

On a semi-related note. I have a greddy type S BOV, i will be venting to the atmosphere. Do i still need to connect a vacume hose to one of those vacume nipples? And if so where?

[MaxType 240]

I've got one side of the solenoid directly to the WG. The other side, I have a tee, binding the compressor and the WG. The pressure sensor hooks up from the intake mani. Too easy.

Utilize the top port on the BOV for vacuum.

Jesse

[koukiKA240]

where should i connect the BOV vacume too?And i have since figured out the AVCR vacume problem. I am going to connect a vacume line from the solenoid to a port just before the TB that alreadys exhists on the intercooler i have.But as far as the BOV vacume hose. What exactly does that do?

[MaxType 240]

BOV basics man, please research the functions of your parts before you blow up your car (blow your turbo in the BOV's case). Anyways, tap off the FPR for vacuum or anywhere else off the intake mani...

Jesse

[koukiKA240]

Be nice man. Why do u think i asked the question? It was to better understand why I need that vacume line. I could have NOT asked and blown everything up, but i didn't i aksed. And thanks for the info.~Sam

[MaxType 240]

Google:

"To eliminate compressor surge when changing gears. Excessive backpressure is created when the throttle is closed during gear changes or deceleration, causing turbo cavitation. This is detrimental to the life of your turbocharger; however fitting a BOV will substantially improve this problem."

You will have to adjust the BOV spring(s) to avoid compressor surge (backpressure forced back into the compressor vs atmosphere or intake stream) on your setup.

Learinng is a process, none of us know it all, we all have to start somewhere