blowoff valve

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gmartin

gmartin

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One thing I've noticed in gt3, which I hope they fix in gt4, is the sound of the blowoff valve. Most cars these days that come with a turbo from the factory don't have a blowoff valve. And actually, there isn't really a need for it. It's not like you're gaining any power, you're actually losing power because it's letting all the air out of the turbo so the turbine has to spin all over again. If you can't hear the blowoff valve in gt3, get a turbo'd car and get the inside view while reving it, you'll hear a sort of hissing sound. While I like the sound the blowoff valves makes, the sound in gt3 is kinda fake and should be fixed in gt4. Or, at least have an option to take it off. The sound in need for speed underground is probably the closest I've heard to a real blowoff valve in a racing game. It actually changed depending on how high the rpms were which was cool. Anyway, that's my two cents.
 
You actually gain power with a blowoff valve. It lets the air out so the turbine will wind up again quicker, allowing you to get away quicker
 
Actually no. If the air is released from the turbo, then it has to spin the turbine again, thus taking longer to give the engine more power. If the air is still in the turbo (with no blowoff valve) then the turbine doesn't stop spinning giving you more turbo responsiveness at a lower RPM and power when you need it.
 
I'll just stay out then. I'll stop emarrasing myself now, before it gets to bad. Yep I think you're right about that *starts whisteling*................................ *starts looking around all wierd* What? I didn't post anything before. :lol:
 
Every factory turbocharged vehicle that I can think of, and that I have seen, has a compressor bypass valve. A cbv is plumbed back into the intake and is almost impossible to hear from outside or even inside the vehicle.

A blow off valve or relief valve is typically vented to the atmosphere. No matter what valve design you have, they all serve one purpose: Prevent compressor surge

If the air is released from the turbo, then it has to spin the turbine again, thus taking longer to give the engine more power.
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Exhaust spins the turbine - The turbine is connected via a shaft to the compressor - The compressor brings in the air. When you let off the gas pedal the throttle plate closes and that extra air that didn't make it into the manifold slams into the plate causing it to go backwards and attack the compressor, forcing it to spin in the opposite direction = bad news. A bov-cbv prevent that air from ever reaching the compressor, and in turn keep it spinning in the right direction.
 
Originally posted by Monster7


Exhaust spins the turbine, the turbine is connected via a shaft to the compressor, the compressor brings in the air, when you let off the gas the throttle plate closes and that extra air slams into the plate causing it to go backwards and attack the compressor forcing it to spin in the opposite direction = Bad news. A bov-cbv prevent that air from ever reaching the compressor, and in turn keep it spinning.
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Exactly.... Well said......


;)
 
I am soooo hoping for blow off valves in GT4 (audible in inside and outside veiws). And not just one sound like in GT2 and GT3.

There are plenty of different sounding ones in real life. (like those on Skylines and those on EVO's etc)
 
Well my car has a bov, and its really load if you add an open air filter. But mine has a recirculater that sends the released air back in to the intake.

Plus after market BOVs give cars the abilty to use higher boost. Example., My car, a 97 Eclipse GST can only get a max of 14 psi but i may be wrong. Adding a aftermarket BOV would give higher boost capability. This a fact I read off of DSM.org

I dont know where you got the idea that the BOv had anything to do with the turbine spinning :)
 
Of course it has something to do with the turbine spinning... that's what produces the pressure to make the bov bo (teehee)!
 
You know what I mean. As in making it spin :irked:
 
Originally posted by gmartin
While I like the sound the blowoff valves makes, the sound in gt3 is kinda fake and should be fixed in gt4.
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They sounded real, not all BOV's and Bypass Valves sound like the ones in NFS:U. But anyway i suppose to add to the realism in GT4 they should add a few different aftermarket ones.
 
Personally, I enjoyed how audible the Blow Off and Bypass Valves were in GT2 and hope that GT4's valves will have new flavor and diversity to add to the realism!;)
 
Adjustable boost would add a touch of realism to the game, as would a functional psi or bar boost gauge. Of course the downfall to more boost is more heat, so there would have to be a way to combat that.

You could use high boost during qualifying or on certain tracks. Or have the option of using racing fuel or a better intercooler to keep the temps low. I don't see it happening but I can always hope.
 
Originally posted by Monster7
Adjustable boost would add a touch of realism to the game, as would a functional psi or bar boost gauge. Of course the downfall to more boost is more heat, so there would have to be a way to combat that.

You could use high boost during qualifying or on certain tracks. Or have the option of using racing fuel or a better intercooler to keep the temps low. I don't see it happening but I can always hope.
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I completely agree. I don't think we can expect that kind of realism for another few titles though.........

Oh, and I love the new avatar......... 3.2 litre VR6 + AWD = Drool......

I wish my Jetta GLI had AWD........




;);)
 
I totally agree with you too, Monster. Boost would be a fun thing to adjust. I think that maybe in GT7 or 8 we'll be able to adjust boost pressure along with A/F ratios, timing, and all the other REAL tuning fun stuff, making cars wicked fast. Who knows though (letting out a patient frustrated sigh:) only time will tell...:banghead:
 
Saw the R32 at our local Auto show (drool).

GT7? GT8? Jeez man... I'm just hoping that GT4 will actually make it out this year :)
 
Yeah, I was being a bit sarcatic, but I am in the same waiting boat as you and everybody else:irked:
 
Originally posted by silviadrifter
I completely agree. I don't think we can expect that kind of realism for another few titles though.........

Oh, and I love the new avatar......... 3.2 litre VR6 + AWD = Drool......

I wish my Jetta GLI had AWD........




;);)
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Thanks man. :) I went from loving, to hating, to loving v-dubbs again after seeing the R32 actually being made.
(I used to own a '68 Bug and my father has been a VW driver for life) An awd Jetta would be cool ****.

By the time GT4 hits the stores, I'll be able to afford an R32. :irked:
 
Originally posted by Monster7
Thanks man. :) I went from loving, to hating, to loving v-dubbs again after seeing the R32 actually being made.
(I used to own a '68 Bug and my father has been a VW driver for life) An awd Jetta would be cool ****.

By the time GT4 hits the stores, I'll be able to afford an R32. :irked:
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I feel ya man...... I lose a year of life (due to stress), everytime they push back the release date. I just can't wate any longer. I need to be playing with all those new cars..... tracks...... features...... Oh man, I soiled myself again.....


;)
 
I frickin want to scream every time I find that the release date has slipped. I mean... what the hell could they be adding that is SO important that we have to wait? The longer I have to wait, the higher my expectations are.

I like VWs, and had a '91 8-valve GTi myself. Unfortunately the last 5 years or so VW's quality has really sucked. :( I hope the R32 isn't in the same boat, 'cause that looks like one fun GTi!
 
Originally posted by Latka
I frickin want to scream every time I find that the release date has slipped. I mean... what the hell could they be adding that is SO important that we have to wait? The longer I have to wait, the higher my expectations are.

I like VWs, and had a '91 8-valve GTi myself. Unfortunately the last 5 years or so VW's quality has really sucked. :( I hope the R32 isn't in the same boat, 'cause that looks like one fun GTi!
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I currently own a 91' 8v Jetta GLI Wolfsburg. I love it, but I'm in the process of selling it, so I can purchase another Silvia......


;)
 
May I add the turbo does not recieve any air from the side the blow off valve is on. The throttle body piping which the BOV is connected turns into exhuast which enters the exhaust housing. The only side which deals with air is through the turbine housing from the intake and Fount mount intercooler.... replying to "qmartin" therefor you "Do Not" lose power from the bov you lose gasmilage from the Mass air flow sensor readings being bouced all over. Or you can just turn it into a bypass valve. Perhaps what you were hearing in the game was a wastegate rather than a bov. They make similar noises to the hissing you described. :)
 
nah I didn't really mean the hissing, I like that sound. What I meant was the burst of air when you let off the throttle at high rpms. It just sounds fake to me that's all. GT4 has potential to make it sound better I hope :)
 
Yeah, it would be super neat to put a Super Sequential on to my Turbo NSX.
I wish there was a boost controller in GT. I have had so many occasions in which I have not been able to balance a car the way I wanted because it had to much power. You should also be able to increase boost with factory units. Speaking of audible differences, I would like to be able to have different exaust systems. God knows Trust (Greddy), HKS, Turbonetics, Garret, and the rest would love to give full support.
I would also like to have a more realistic boost gauge.
 
I tell you, as much as I love racing, cars, and racing cars, overboost is turning out to be a hot topic to this Chat. The reason why people wouldn't want to have Overboost in a game is because real racers don't use such a thing. Overboost is kind of more like drag racing and illegal street racing (even though I don't endorse it). I don't think an overboost will sell for GT4 cars even though a Trial-tuned Toyota Celica SS-II will most likely be in GT4. I wouldn't even recommend it for racing in GT4. I wouldn't recommend it especially for passing. It would make GT4 more of an arcade game than a arcade/simulation.

Well, that's what I think. And I tried to tell my side without saying "ricer," "rice rocket," or anything like that, because that's not my style.
 
I think that they should have seqeintual (spelling?) blow off valves and/or waste gate blow off valves.I also think that the rally cars should have the waste gate blow off valve sound like the real WRC cars.
gtr.gif
 
They should have turbo lag in the game.
 
yes! Turbo lag! where did it go!?!
GT1 had major turbo lag, and it was fairly realistic (but a bit excessive sometimes). The only thing they screwed up in GT1 regarding turbo lag was the fact that you still had lots of lag when revving in neutral, which isn't very accurate.

In GT3, you can take a 1,000 HP supra with a basketball-sized turbo, and it will make full boost at 1100 RPM! The big turbos have no disadvantage anymore, except for wheelspin. I hope turbo lag returns.
 
Originally posted by godzilla_GTR
I think that they should have seqeintual (spelling?) blow off valves and/or waste gate blow off valves.I also think that the rally cars should have the waste gate blow off valve sound like the real WRC cars.
gtr.gif
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I'll bet $100 you don't know what any of that means
 
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