Which brand of BOV r u Speed3ers running? Also is it VTA or Recirc?

is there a growing sentiment that VTA should be OK in the long run? I'm concerned about blasting too many hydrocarbons at my cat (ughdance)
 
I don't understand??? Why is VTA bad??? Can someone explain this? Every other turbo car comes stock like ours did...then everybody always switches to VTA and no problems. So why is everyone against it on our car?
 
mspro19 said:
I don't understand??? Why is VTA bad??? Can someone explain this? Every other turbo car comes stock like ours did...then everybody always switches to VTA and no problems. So why is everyone against it on our car?

Whah happens when you vent to air is that the turbo sucks the air in, then when you clutch in and the air is let out of the charge pipe, instead of it going back into the system after the MAF but before the turbine, it is released from the system entirely. This causes a momentary rich condition which can effect drivability of the car.

You may notice the car puffing black smoke on full throttle shifts and if you clutch in and coast, the car may even stall. This may not have a huge effect at first, but over time the plugs are going to get fouled from fuel deposits that do not burn properly due to the fact that there would be way too much fuel in teh combustion chamber then there is supposed to be.

This was a very common issue with DSM's as well as the WRX. If you're not worried about the occasional puff of black smoke and your car stumbling from time to time on clutch in, as well as the need to replace plugs more often, then go ahead with the VTA. I'd reccomend that you recirculate or at the least use some sort of hybrid valve like the WRX guys use. That would lessen the negative effects and still give you the sound you're looking for when you're getting off the throttle.
 
ill_eagle94 said:
Whah happens when you vent to air is that the turbo sucks the air in, then when you clutch in and the air is let out of the charge pipe, instead of it going back into the system after the MAF but before the turbine, it is released from the system entirely. This causes a momentary rich condition which can effect drivability of the car.

You may notice the car puffing black smoke on full throttle shifts and if you clutch in and coast, the car may even stall. This may not have a huge effect at first, but over time the plugs are going to get fouled from fuel deposits that do not burn properly due to the fact that there would be way too much fuel in teh combustion chamber then there is supposed to be.

This was a very common issue with DSM's as well as the WRX. If you're not worried about the occasional puff of black smoke and your car stumbling from time to time on clutch in, as well as the need to replace plugs more often, then go ahead with the VTA. I'd reccomend that you recirculate or at the least use some sort of hybrid valve like the WRX guys use. That would lessen the negative effects and still give you the sound you're looking for when you're getting off the throttle.

Well not to say that you are wrong, but my car doesn't feel any different from when I first bought it...back in Oct. 06. Now the car does get real black in the tailpipe but that happened as soon as I drove off the lot...as do most turbo cars. Everyone that I know that has a turbo has VTA and no problems. My car def. does not stumble or feels like it going to stall...don't know but I'm keeping it the way it is and works fine...
 
mspro19 said:
Well not to say that you are wrong, but my car doesn't feel any different from when I first bought it...back in Oct. 06. Now the car does get real black in the tailpipe but that happened as soon as I drove off the lot...as do most turbo cars. Everyone that I know that has a turbo has VTA and no problems. My car def. does not stumble or feels like it going to stall...don't know but I'm keeping it the way it is and works fine...

That's cool. I'm not saying that it is definately going to happen, I'm just giving the possibilities, as well as examples of MAF meterd cars that people have run with VTA and hed undesirable effects.
 
Again vta isn't so great. Million threads about this. I use a CP-E HKS SSQV kit with recirculation. I have the obvious stumble and poor driveability when using VTA. And as a side note my WRX ran like crap in full VTA. I always had a hybrid valve on that car to counter the poor running.
 
Another thing to realize is that when you run the VTA, the unmetered air escapes, and the fuel goes through - that fuel is spit out onto the exhaust manifold where it ignites and throws flames at your cats, not a good thing. Cat efficiency will likely be effected over time and they aren't cheap to replace. To my thinking this is only another reason to go catless. Keep your stock parts - swap them on for inspection, then switch back and run a more free flowing exhaust.

FWIW - Even a full recirc(aka BPV) setup still has a bit of this problem, but not anywhere close to a VTA setup. It's the nature of the beast when coming off boost. If you are catless you will get small amounts of afterfire with a BPV and larger amounts with a BOV.

Like anything else - it is what it is.
 
Micah said:
Another thing to realize is that when you run the VTA, the unmetered air escapes, and the fuel goes through - that fuel is spit out onto the exhaust manifold where it ignites and throws flames at your cats, not a good thing. Cat efficiency will likely be effected over time and they aren't cheap to replace.

Just as a correction- it has nothing to do with flames or heat... if your HC emissions were to ignite within the cat, the increase in temperature would be so negligible compared to the exhaust gas temps on a car (let alone at FI car) that that really wouldn't be an issue.

The excessive HC's just eat away at the compounds within the cat and render it ineffective.

Another thing that I don't really know nearly as much about but don't the HC's accelerate the deterioration of polymer in the exhaust system and the vanes in a turbo? (scratch)

I really like the sound of VTA but I can't justify it if switching is going to rush my car toward breaking down.(boom02)
 
3000 miles on mine, runnin a HKS in full VTA

no problems at all.



The first time it stumbles, stalls, or back fires it will be changed. Untill then... it's stayin
 
Ms3Xeoc said:
3000 miles on mine, runnin a HKS in full VTA

no problems at all.



The first time it stumbles, stalls, or back fires it will be changed. Untill then... it's stayin


again boyz, you guys are so worried about "how it feels to your butt/ass" ...

the BUTT DYNO ain't always the best tool to use.

You need some type of scanner to read the A/F so you can see exactly what full VTA does in between shifts, etc...

i gaurentee when you see what is actually does and how it fouls ur plugs and you can actually lose performance, you will change ur ways.

until then, rice it up. VTA or the sound of the BOV is nothin except Rice (kissass)
 
Yeah, this subject has been beaten to death on the DSM (eclipse/talon) forums time and time again. It's always better to recirculate instead of vent. There's a reason they call the stock valve a diverter (or compressor bypass) valve and not a BOV, it doesnt just vent pressure when you let off the throttle, it also opens under very light loads to allow air to bypass the turbo, which puts less load on the engine under very light acceleration.... which means better gas mileage under light load driving. My MPG dropped by 2mpg when I vented the stock BOV on my eclipse. The car ran fine, but the MPG dropped anyway. I hooked it back up. Well... for a while. I eventually got a blow-thru maf sensor that went between the BOV and the throttlebody so the air venting was unmetered and I put a greddy BOV on with the tighter spring, which clamps shut all the time, even under light vac. It does surge a little bit, but the spool time dropped like a rock. I dont know if a tighter BOV on a MS3 would drop spool time though, I remember reading somewhere that the ECU smooths out spool to reduce the felt torque steer. I wouldnt want to surge the turbo on a new car anyway, the stock CBV is way more responsive than an aftermarket BOV and has almost zero surge. It's nearly identical in design to the 1g dsm CBV, except the eclipse one is metal. I kind of wonder if the 1g dsm one would directly fit... or vice versa.

Also, does anyone know what PSI the stock MS3 valve starts leaking at? I know the stock 1g dsm valves start to leak at 20 to 22 psi.. (which is why I had to replace mine with a greddy).
 
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destrux said:
Yeah, this subject has been beaten to death on the DSM (eclipse/talon) forums time and time again. It's always better to recirculate instead of vent. There's a reason they call the stock valve a diverter (or compressor bypass) valve and not a BOV, it doesnt just vent pressure when you let off the throttle, it also opens under very light loads to allow air to bypass the turbo, which puts less load on the engine under very light acceleration.... which means better gas mileage under light load driving. My MPG dropped by 2mpg when I vented the stock BOV on my eclipse. The car ran fine, but the MPG dropped anyway. I hooked it back up. Well... for a while. I eventually got a blow-thru maf sensor that went between the BOV and the throttlebody so the air venting was unmetered and I put a greddy BOV on with the tighter spring, which clamps shut all the time, even under light vac. It does surge a little bit, but the spool time dropped like a rock. I dont know if a tighter BOV on a MS3 would drop spool time though, I remember reading somewhere that the ECU smooths out spool to reduce the felt torque steer. I wouldnt want to surge the turbo on a new car anyway, the stock CBV is way more responsive than an aftermarket BOV and has almost zero surge. It's nearly identical in design to the 1g dsm CBV, except the eclipse one is metal. I kind of wonder if the 1g dsm one would directly fit... or vice versa.

Also, does anyone know what PSI the stock MS3 valve starts leaking at? I know the stock 1g dsm valves start to leak at 20 to 22 psi.. (which is why I had to replace mine with a greddy).
the flange is the same... you can bolt on a dsm valve to a ms3.
i just ordered the forge motorsports valve for the 1st gen eclipse.
it is a great valve on those cars, and i am not 100 % pleased with my greddy.
 
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