Forge Valve install/impressions

[subparpunk03]

beleive what you want man. We explained it as best as we could, and I showed you a post with tests that SHOW the cold pipe ISN'T venting 200 degree air back to the intake tract. In real driving conditions the air from the cold pipe is roughly between 80 and 130 degrees, and when venting the air expands which cools it more.... pv=nrt man. Thats basic physics.

I don't know what more we have to do to explain this, so now the onus is on you to show us that vta lowers the average temp in the cold pipe. All the evidence presented so far indicates that the noticed power difference is NOT from temp difference.

 

[sleeper3]

here is the difference:

if your engine is spinning at 1 rpm the air being used is 4000 times less than at 4000 rpm. think about it... each intake stroke is filling each cylinder with a volume of compressed air. the ratio between the air used on an intake stroke and the volume of air held in the ducting between the turbo outlet and the head of the motor will tell you how long the "effected" air will be effecting the power produced by your engine due to it's increased temperature. my guess is that it would be so short before the air is cleared that you would not notice.

 

[sleeper3]

beleive what you want man. We explained it as best as we could, and I showed you a post with tests that SHOW the cold pipe ISN'T venting 200 degree air back to the intake tract. In real driving conditions the air from the cold pipe is roughly between 80 and 130 degrees, and when venting the air expands which cools it more.... pv=nrt man. Thats basic physics.

I don't know what more we have to do to explain this, so now the onus is on you to show us that vta lowers the average temp in the cold pipe. All the evidence presented so far indicates that the noticed power difference is NOT from temp difference.

♥pv=nrt♥

 

[sleeper3]

here is something to think about:

I was thinking about what would be more efficient between completely venting the compressed air to keep the turbo impeller spinning as fast as possible, or venting not as much, so that on a very fast shift, you have a lot of residual boost in the intake tract, but the impeller is spinning slower.

I'm sure there has to be a happy medium between the two, but where would it be?

interesting....

 

[sleeper3]

oh also, I just took my girlfriend for a ride and she said she loves the sound the valve makes! she said it sounds like we're playing video games.

 

[Ziggo]

if my theory is correct than the over all temp is reduced by much more than 20 degrees and its the overall temp of the air entering the engine at 1rpm or 4000 rpm what diff does it make what rpm? the intake charge is way colder cuase its not getting that 190degree splash from recuric.

The point is for one revolution out of 60 the engine is getting slightly hotter air. It is only hotter due to heating by the wheel and some efficiency factor and I bet most of this heat is dissipated in the intercooler. Most of the temperature increase is lost due to the reduction in pressure as it is vented back into the intake. In fact, with an awesome intercooler, the air expanding out of the valve could be COLDER than ambient. Its how every refrigeration (save thermo-electric)system works.

Even if there is a minimal increase in temperature were to have an effect on the engine it would most likley only affect 1 revolution of the engine which when running at 4000RPM is only 15 milliseconds.

Thus the whole BOV>BPV arguement is based on a very slight performance decrease for 15 milliseconds, which is probably occurs before you even manage to get the throttle to the floor.

 

[sleeper3]

The point is for one revolution out of 60 the engine is getting slightly hotter air. It is only hotter due to heating by the wheel and some efficiency factor and I bet most of this heat is dissipated in the intercooler. Most of the temperature increase is lost due to the reduction in pressure as it is vented back into the intake. In fact, with an awesome intercooler, the air expanding out of the valve could be COLDER than ambient. Its how every refrigeration (save thermo-electric)system works.

Even if there is a minimal increase in temperature were to have an effect on the engine it would most likley only affect 1 revolution of the engine which when running at 4000RPM is only 15 milliseconds.

Thus the whole BOV>BPV arguement is based on a very slight performance decrease for 15 milliseconds, which is probably occurs before you even manage to get the throttle to the floor.

best first post ever.

 

[ElBartoRex]

Wow, im sorry I said anything.

Powerslave's argument makes no sense...

you are using a vent to atmostphere valve on a MAF sensored car...

you car thinks its getting x amount of air and is actually getting y amount.

Your car adds enough fuel for x amount of air..

your MAF readings are innacurate, your car runs rich, backfires, idles funny...the list goes on.

of all of tuners and manufacturers I have ever met, professional and novice, you are the only person i have ever heard of that claims a VTA valve makes more power...

I don't care what you read in 'turbo magazine'

 

[speed3shon]

here is something to think about:

I was thinking about what would be more efficient between completely venting the compressed air to keep the turbo impeller spinning as fast as possible, or venting not as much, so that on a very fast shift, you have a lot of residual boost in the intake tract, but the impeller is spinning slower.

I'm sure there has to be a happy medium between the two, but where would it be?

interesting....

there doesnt have to be a happy medium... either way, your venting compressed air from the hot side (post turbo) to the cold side (pre-turbo).

this allows the turbo to continue spinning regardless of whether the air vents to atmosphere, or back in the intake.

even if you tune for VTA, there is no benefit. if your saying its so much air, thats that much more air you have to send through a restrictive filter to replace it. but, its not that much air.

as long as the intercooler is relatively efficient, and not heatsoaked, the minimal difference will be irrelevent after the air passes through the intercooler.

 

[sleeper3]

there doesnt have to be a happy medium... either way, your venting compressed air from the hot side (post turbo) to the cold side (pre-turbo).

this allows the turbo to continue spinning regardless of whether the air vents to atmosphere, or back in the intake.

even if you tune for VTA, there is no benefit. if your saying its so much air, thats that much more air you have to send through a restrictive filter to replace it. but, its not that much air.

as long as the intercooler is relatively efficient, and not heatsoaked, the minimal difference will be irrelevent after the air passes through the intercooler.

I wasn't talking about vent to atmosphere versus vent to intake. I was talking about how big the vent port is... does it let all the air out or just enough to minimize the backpressure on the turbo.

 

[speed3shon]

you want to vent ALL boost, and then AT LEAST as much air as the turbo pushes into the intake during the shift. if you cant vent that much, it will cause compressor surge, and slow the turbo.

if you cant do that with a bypass valve (lets face it, theres only so much air you can dump out of a 1" valve, and through a 1" tube) thats when it benefits to run a BOV with a bigass valve/vent.

 

[sleeper3]

you want to vent ALL boost, and then AT LEAST as much air as the turbo pushes into the intake during the shift. if you cant vent that much, it will cause compressor surge, and slow the turbo.

if you cant do that with a bypass valve (lets face it, theres only so much air you can dump out of a 1" valve, and through a 1" tube) thats when it benefits to run a BOV with a bigass valve/vent.

not true, as you have the rotational inertia of the impeller and the force of exhaust still being expelled from the engine (yeah, it's less, but there is still some) and the slight increase in air pressure upstream of the turbo, due to the venting. none of these create a huge advantage individually, but together they definitely count for something.

 

[speed3shon]

right, thats why i said you want to vent all boost + the air the turbo will continue to advance through the intake from the time the bypass valve opens to the time the motor begins to build boost again (closing the bpv).

keeping the rotational inertia of the impeller is, afterall, the whole point of a dump valve, whether its a bypass or blowoff valve.

 

[patty AT forge]

Actually the best possible set-up would be a vent to vacuum set-up. Honest

 

[speed3shon]

Actually the best possible set-up would be a vent to vacuum set-up. Honest

well, if your gonna go there, there are alot of systems that could be better engineered. they just arent feasible, economical, or necessary.

i mean, if everything came perfect on a car, there wouldnt be much of a need for aftermarket systems eh?

(wink)

 

[Powerslave]

ha. first of all. cylinder.

now that thats out of the way...

do you even know how heat relates to an engine? it actually causes the air fuel mixture to burn easier... which is called detonation in the event that it combusts in the cylinder before the spark plug fires... thus, for hotter air, you need more stable fuel (higher octane, because it burns slower) to prevent detonation...

cooler air is more dense (more oxygen particles in a given space), all that means is that you can push more fuel into the cylinder, thats where the power comes from...

yes, heat robs you of power.

no, venting off hot air will NOT gain you power, because you know what the motor will do? produce MORE HOT AIR.

give it a shot. use any logging tool, and log the differences in IATs vented and recirced on the same vehicle in the same conditions. you wont see a difference.

IF... and thats a big ******* if.... you see a difference, do you even know where to look for it on the logs? it will be during, or in the 1/1000ths of a millisecond after a shift (where you will be running too rich anyways, oops, there goes your power from dumping hot air). when you are not accelerating. try again to convince me it will make a difference

its called physics numbnuts. read a freakin book.

i know how it works and i know about the running rich part i'm taking care of that, you physics are backwards!! yes hotter air requires higher octane to prevent detonation cuase there is not enough oxygen. Your awnser is FLAWED AND DOENSNT MAKE ANY SENSE! your saying venting off hot air will make the engine produce hot air???(braindead If the intake temp is colder you have more oxygen, better combustion and more power. thats it, on boost vta is delivering the SAME amount of air as recur and it much colder than haveing a shot of 200 degree air. if your going to respond atleast say something that sounds halfway intelligent....

 

[sleeper3]

Actually the best possible set-up would be a vent to vacuum set-up. Honest

but if you vented to vacuum, the turbo would have to completely recharge the entire intake track with air. seems like that would take way longer than if the impeller just slowed down a bit. maybe I am not explaining myself well enough.

 

[subparpunk03]

(bang)

 

[sleeper3]

i know how it works and i know about the running rich part i'm taking care of that, you physics are backwards!! yes hotter air requires higher octane to prevent detonation cuase there is not enough oxygen. Your awnser is FLAWED AND DOENSNT MAKE ANY SENSE! your saying venting off hot air will make the engine produce hot air???(braindead If the intake temp is colder you have more oxygen, better combustion and more power. thats it, on boost vta is delivering the SAME amount of air as recur and it much colder than haveing a shot of 200 degree air. if your going to respond atleast say something that sounds halfway intelligent....

I think to convince anyone, you're going to have to produce IAT readings with VTA and Recirc or dyno charts with both. that's the only way I am going to believe you. I think you'll be surprised at the results.

 

[Powerslave]

Wow, im sorry I said anything.

Powerslave's argument makes no sense...

you are using a vent to atmostphere valve on a MAF sensored car...

you car thinks its getting x amount of air and is actually getting y amount.

Your car adds enough fuel for x amount of air..

your MAF readings are innacurate, your car runs rich, backfires, idles funny...the list goes on.

of all of tuners and manufacturers I have ever met, professional and novice, you are the only person i have ever heard of that claims a VTA valve makes more power...

I don't care what you read in 'turbo magazine'

you only run ritch between shifts you have effeciant boost when your on boost...make sense?