Alright, BOV question for you all... - Page 2

UncleBob · #16 02-13-2007, 12:15 AM

hehe, is this a question or just bragging?

The reason it blew off is because you used the $20 Kmart special BOV. Get one that actually has a bolt on flange instead of that rediculously cheasy pinch bolt setup, and I promise you, it won't blow off anymore....even with your amazing 1000psi capable engine.

Of course, that would ruin the bragging rights eh?

2.2 Straight six · #17 02-13-2007, 12:24 AM

Quote:

Originally Posted by CassiesMan

I see that sarcasam is not your strong suite...

1,000psi is almost 70 times atmospheric pressure, the silicome hoses couldn't stand anything like that, and neither could much of the solid piping.

does that catch can blow off? i can't see any reason it would, i think it was probably just the BOV firing out from near the grill and buggering everything around it.

Moppie · #18 02-13-2007, 01:32 AM

Quote:

Originally Posted by 2.2 Straight six

1,000psi is almost 70 times atmospheric pressure, the silicome hoses couldn't stand anything like that, and neither could much of the solid piping.

It was sarcasm, your supposed to laugh

Moppie · #19 02-13-2007, 01:37 AM

After watching that Video, are you sure it was only the BOV that came off?

There was a LOT of orange flame and pressure released when it popped.
Looked more like the head tried to make a break for freedom.

Moppie · #20 02-13-2007, 01:49 AM

Alright, I just watched a higher res video on the visionboy website.

The BOV deffinitly came out the top of the engine, the bonnet was lifted off and flexed around the hinges and front catch.
There is also considerable fire damage to the front of the bumper, the paint is well and truly toasted.
When the bang happens there is a large orange fireball in the right front corner, where the BOV is located, this appears to cause the fire damage to the bumper, and also appears to cause a lot of flex in the side of the bumper. I would assume its this fireball that also dislodges the BOV and throws it out of the engine bay through a gap in the flexed bonnet.

Now either thats one f-ing big blow back through the intake, or, note the location of the oil catch can, and the fact that it's missing after the explosion.

CassiesMan · #21 02-13-2007, 09:33 AM

Quote:

Originally Posted by Moppie

Now either thats one f-ing big blow back through the intake, or, note the location of the oil catch can, and the fact that it's missing after the explosion.

Thats what I've been saying. The only problem is VB hasn't listed anything on his website about it at all, and I and my bud have gone to a bunch of IS/2JZ forums, and again, nothing.

Moppie · #22 02-13-2007, 05:48 PM

Generaly when a race car has a major accident, the owener tends to be very reluctant about sharing with the world why.
There is a huge amount of pride involved.

It looks to me like the oil catch can blew up.
The cause of ignition, and explosive vapour is open to speculation, but thats what it looks like.
Its not the first time Iv seen it happen either.

Igovert500 · #23 02-14-2007, 04:48 AM

Love to see some pics under the hood now. While it's certainly possible to blow the BOV off with a hell of alot of pressure at 2bar... (I shot a pressure tester across a garage and dented the wall 12 feet away at 1 bar) ...that doesn't explain the explosion.

Is his intake down below the passenger headlight...looks like it. It appears that the explosion was below the oil catch can. Pics of the damage would help. But I'm gonna guess one hell of a blowback.

CassiesMan · #24 02-14-2007, 09:28 AM

No pics of the damage besides the ones in the vid, sorry. Guess we just have to leave this one up in the wind?

Steel · #25 02-15-2007, 08:25 AM

I will officially put my stance on gremlins.

^those ones.

2.2 Straight six · #26 02-15-2007, 08:48 AM

if you watch the video, at about 56-58 second in, the engine "looks" different to how it does in the photo on the site. by that i mean it has the plastic cover on and you can see the air filter, i think the catch can was added after the video was shot.

KiwiBacon · #27 02-16-2007, 08:15 AM

Quote:

Originally Posted by 2.2 Straight six

you do realise that you don't even need a BOV? turbo'd race race don't use them. they have something similar called a pop-off valve which is an over-boosting fail-safe.

BOVs are a street car thing.

Have you never seen or heard a WRC car?
Big turbos, as much boost as they can pull through the restrictors and blow off valves which chirp loudly every time the throttle is closed.

2.2 Straight six · #28 02-16-2007, 02:16 PM

from what i was told by some guys who work at my college and a merc dealership, that's the wastegate, and some noise is made by vibrations in the inducted air bouncing back and forth when the throttle plate is closed.

on top of that, in the pictures i have of various rally/race engines, they don't have BOV, only pop-off/surge valves.

UncleBob · #29 02-16-2007, 02:24 PM

all race cars have BOV. Depending on the model of BOV, they can also act as a "pop off valve" (ie, over-boost protection).

Basically any turbo engine that has high boost wants a BOV to prevent surging and also keep the turbo spooled when closing the throttle. Only time I would recommend not having one is if you had a very low boost setup, IE, under 10psi.

KiwiBacon · #30 02-16-2007, 03:07 PM

Quote:

Originally Posted by UncleBob

Only time I would recommend not having one is if you had a very low boost setup, IE, under 10psi.

Or if you've got a diesel with no throttle plate.

It cracks me up how the ricers go out and buy the loudest BOV they can for their 5 psi of boost to make it sound impressive.
Especially fitted to cars with a MAF on the airbox, you see them go so rich they spew black smoke just after the BOV opens.

POST REPLY TO THIS THREAD