Greddy Type-S Bov install???

[kareem17]

hey guys, I just installed my new Greddy Type-S bov today. With the stock bov my boost gauge would read 0.95 kpa (14.05psi) at the max, but after the install when I went for a drive my boost gauge read 1.06 kpa (15.68psi)... I have the boost gauge holding the peak boost. Is this bad that it is reading 1.06 kpa after a greddy swap with the stock bov? Do I have to worry about anything?

 

[Fahrenheit]

Your stock bov was leaking and now that you put on the type s it wont leak and should hold whatever resonable boost you set it to. Since you have the t-28 i would turn your boost down till you get a fuel pump and a rewire. But on the stock turbo 15-16 is fine.

 

[kareem17]

Your stock bov was leaking and now that you put on the type s it wont leak and should hold whatever resonable boost you set it to. Since you have the t-28 i would turn your boost down till you get a fuel pump and a rewire. But on the stock turbo 15-16 is fine.

since i don't have a mbc yet, is this boost level fine?

 

[JoeWagon]

If you don't hit fuel cut, 100% IDC, or knock, then yes... that boost level is fine.

 

[DCsGST]

You will be fine at that boost until your fuel system is up to par. I ran 15 on mine when I installed it, and I never hit fuel cut with only a rewired FP.

 

[kareem17]

thanks guys.... also there is a adjustment screw on top of the bov. How many threads is everyone leaving?

 

[DCsGST]

Since you are only running 15 psi, you will have a lot of threads showing. Loosen it up til it won't leak at idle, then add 2 turns to it. When you raise the boost later, add a few threads. If the car bucks at part throttle blowoffs or you hear compressor surge, you have it adjusted too tight. The type S is a PITA to adjust just right, but once it's set you'll have no problems.

 

[kareem17]

what does compressor surge sound like or feel like?

 

[DCsGST]

You won't really "feel" compressor surge, but you'll hear it. The best way to test for it is to either have somebody in the car and with it runing do some blowoffs both full and part throttle. On part throttle blowoffs, you will either hear a weezing whistle, or a fast wurr wurr wurr sound as the air slams back into the comp. wheel.

If you feel crazy enough, unhook the pressure source from the BOV and do ONE revv making a few pounds of boost using your hand at the TB. THAT will definatley give you comp surge, but I wouldn't reccomend it since it isn't good for the turbo.

I did this by accident when used to have the pressure source to the BOV T'd for a mbc and when I redid my BOV lines I went with the pressure source off the comp housing instead. Well, I capped off that unused nipple on the T to the BOV that I was no longer using. Well, to make a long story short, that cap popped off under boost one night and the next day I was adjusting the Type S and noticed a hissing sound (vacuum leak) and the BOV wasn't reacting and I was getting nasty surge. That's when I noticed the cap missing.

Point you ask? I now know the horrible sound of compressor surge as it's burned into my memory forever.

 

[kareem17]

is the "whistling" sound compressor surge? right now i have 8 threads above the nut. Do I add more threads? like make it 9, 10, 11? because I am getting some whistling with 8 on there now

 

[DCsGST]

the whistling is normal. I'll have to count mine, but I think I've got 7 threads or so and I can hold 19 psi fine. Sounds like you have it loose enough, now just make sure it's not leaking at idle and you'll be fine.

Some people leave 4 or 5 threads, but when I did this it was WAY too tight and the car would buck under part throttle blowoffs.