Stock BOV test
Stock BOV and Forge DV testing
While I was working on my car, I had the vacuum pump out so I hooked it up to the stock BOV (not on car). With me blowing on the end of the valve that sees boost (probably 8 psi or so) the valve started to leak presure at 14 inches of vacuum and opens at 16.5 inches of vacuum.
I know, not very scientific but when I get a chance I want to compare that the Forge that is on the car.
I know, not very scientific but when I get a chance I want to compare that the Forge that is on the car.
Last edited by timzcat; Jul 9, 2003 at 10:30 AM.
Which model Forge do you have? the vta or recirc??
I was planning on doing a stealth (the black one) forge recirc as my first mod.
And thanx again for checking your tt harness for me man. I'm gonna give the car a few weeks to act up again before I reattach my boost gauge or turbo timmer, but when I do reattach the turbo timer I'll be reversing the blue green config to match what we talked about.
I was planning on doing a stealth (the black one) forge recirc as my first mod.
And thanx again for checking your tt harness for me man. I'm gonna give the car a few weeks to act up again before I reattach my boost gauge or turbo timmer, but when I do reattach the turbo timer I'll be reversing the blue green config to match what we talked about.
More on the testing.
I took the forge off the car to test it.
The Forge valve opens at about 1/2 to 1 inch of vacuum. Remeber I am using a mightyvac pump and they are not dead accurate.
The Forge valve relies soley on the vacuum barb to control the valve. That is why it doesn't matter how it is installed.
This is quite interesting though. By this theory, the Forge is wide open at idle and remains open until you drop the engine vacuum back down to 0 and start to make boost. Then the valve is closed and remains that way until the manifold loses boost preussure by closing the throttle. as soon as 1 in.Hg is in the intake the valve can open again and it is pin open at 14 in.Hg.
In theory this valve should be very responsive to compressor surge since it it only takes 1 inHg to start the valve open. Interesting that it is still not as smooth as stock. I think I am going to have to buy the spring kit and see what a softer spring does. Since it really doesn't affect keeping the valve closed to much since the valve is often open.
The only variable left is the size of the valve openings. If they were larger it would probably have enven less oppurtunity to
surge. But in all actuality in reference to my other post, two valves would bleed off more air all at once. There is no diaphram in the valve, it uses two o-rings th seal the aluminum piston on the vacuum side. very simple design that works well an it is easy to maintain.
Edit: An explanation can also be found in the https://www.evolutionm.net/forums/sh...&highlight=bov post.
I asked Forge to comment on these findings.
I took the forge off the car to test it.
The Forge valve opens at about 1/2 to 1 inch of vacuum. Remeber I am using a mightyvac pump and they are not dead accurate.
The Forge valve relies soley on the vacuum barb to control the valve. That is why it doesn't matter how it is installed.
This is quite interesting though. By this theory, the Forge is wide open at idle and remains open until you drop the engine vacuum back down to 0 and start to make boost. Then the valve is closed and remains that way until the manifold loses boost preussure by closing the throttle. as soon as 1 in.Hg is in the intake the valve can open again and it is pin open at 14 in.Hg.
In theory this valve should be very responsive to compressor surge since it it only takes 1 inHg to start the valve open. Interesting that it is still not as smooth as stock. I think I am going to have to buy the spring kit and see what a softer spring does. Since it really doesn't affect keeping the valve closed to much since the valve is often open.
The only variable left is the size of the valve openings. If they were larger it would probably have enven less oppurtunity to
surge. But in all actuality in reference to my other post, two valves would bleed off more air all at once. There is no diaphram in the valve, it uses two o-rings th seal the aluminum piston on the vacuum side. very simple design that works well an it is easy to maintain.
Edit: An explanation can also be found in the https://www.evolutionm.net/forums/sh...&highlight=bov post.
I asked Forge to comment on these findings.
Last edited by timzcat; Jul 9, 2003 at 10:31 AM.
