Yellow Bullet Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
616 Posts
Discussion Starter #1
Is it possible to force the BOV open with 20psi on a Precision 76mm on a 331 ford. I had a master power T-70 on 17psi and it ran 113mph in the 1/8th. Now with the 76mm on 20psi, it still runs 113mph and about a tenth and a half faste. Just wondering if I could be leaking boost by pushing the valve open.
 

·
Custom Engine Shop
Joined
·
3,812 Posts
Is it possible to force the BOV open with 20psi on a Precision 76mm on a 331 ford. I had a master power T-70 on 17psi and it ran 113mph in the 1/8th. Now with the 76mm on 20psi, it still runs 113mph and about a tenth and a half faste. Just wondering if I could be leaking boost by pushing the valve open.
What is the hotside AR?

How much hotside back pressure?
 

·
Registered
Joined
·
632 Posts
when you are under boost the boost reference hose that goes to the top of the BOV will put the same amount of boost on top of the BOV as whats under plus the little extra from the spring. when the throttle body is closed you then have vacuum on the intake side for the throttle body which in turn will have lower pressure on the top of the BOV so then the boost will push it open to dump the boost
 

·
Super Moderator
Joined
·
9,240 Posts
Are you getting the boost in faster at 20lb vs. 17lb? That may be your ET gain.

Is the boost steady on top end? If so, you probably don't have a leak at the blow off.

Sometimes more boost does not equal more airflow/power. The turbo gets to a point where there's too much backpressure, and too much turbo speed, to make more power.
 

·
Registered
Joined
·
616 Posts
Discussion Starter #7
The hotside a/r is .96 on a t4 frame. It has a 3 inch downpipe all the way out. I know the car will be faster when I get the 60' times down. I feel like there is a lot more power left in the turbo though. Precision rates it at 30 psi and 1200hp.
 
1 - 7 of 7 Posts
Top