installed bov, and car stalls when off throttle
aiight. at least you have an excuse. Being a redneck is no excuse for Magna.
however, you're from MA and look pretty white in this pic:

so one only assumed.
compromised.
however, you're from MA and look pretty white in this pic:

so one only assumed.

compromised.
Check this thread out:
https://www.miataturbo.net/forum/sho...ght=Bailey+VTA
Ran my Bailey's VTA with my Greddy set-up on Jim's throttle body intake piece (yes, i had to JBweld it there) with only slight rich conditions while shifting. Not sure if any of this info translates to your set-up with your BOV, but it might be helpful while you put together your recirc system.
https://www.miataturbo.net/forum/sho...ght=Bailey+VTA
Ran my Bailey's VTA with my Greddy set-up on Jim's throttle body intake piece (yes, i had to JBweld it there) with only slight rich conditions while shifting. Not sure if any of this info translates to your set-up with your BOV, but it might be helpful while you put together your recirc system.
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From: worcester ma
thanx alot
i get no bucking when shifting, nothing like that,
it just stalls when i lift throttle slowing to a light and throw it in neutral
but if i ween it off boost, say lift off, then keep it in gear,
and slow down to say 2500rpm and then put it in neutral it idles down just fine
so im assuming its just getting too much fuel and kills it self,
so if i throttle it down while not in boost, its fine
i get no bucking when shifting, nothing like that,
it just stalls when i lift throttle slowing to a light and throw it in neutral
but if i ween it off boost, say lift off, then keep it in gear,
and slow down to say 2500rpm and then put it in neutral it idles down just fine
so im assuming its just getting too much fuel and kills it self,
so if i throttle it down while not in boost, its fine
Yes, as everyone has basically stated here you issue is the BOV is open at idle. Basically you are getting an intake leak. The ECU expects there to be x amount of air in the combustion chamber, gives y amount of fuel. The problem is x is less then what the ecu thinks since air is now escaping from the intake tract via the open BOV. This causes a constant rich condition which is your issue with the car wanting to die.
This is a major issue.
A minor issue (imo) is the fact that with a MAS/MAF/AFM based system when the BOV opens (between shifts under boost, or simply deaccel under boost, aka basically when the BOV SHOULD open) the ecu once again thinks there is more air then there actually is, and you go rich. This is much less of an issue because it only happens for half a second at most, while the open bov at idle happens constantly.
Your fixes are:
1. Replace the DSM BOV with a good VTA BOV.
2. Plumb the DSM BOV recirc pipe back into the intake tract before the turbo.
3. Run an EMS (standalone or some piggybacks) that allow you to convert to MAP based air metering system.
That is pretty much it.
This is a major issue.
A minor issue (imo) is the fact that with a MAS/MAF/AFM based system when the BOV opens (between shifts under boost, or simply deaccel under boost, aka basically when the BOV SHOULD open) the ecu once again thinks there is more air then there actually is, and you go rich. This is much less of an issue because it only happens for half a second at most, while the open bov at idle happens constantly.
Your fixes are:
1. Replace the DSM BOV with a good VTA BOV.
2. Plumb the DSM BOV recirc pipe back into the intake tract before the turbo.
3. Run an EMS (standalone or some piggybacks) that allow you to convert to MAP based air metering system.
That is pretty much it.
I have had my Turbo XS Type S vented to atmosphere for at least a year and it has never stalled. I know it's not the right way to do it, but it works.
Do you have the evil idle dip? When I had the JRSC on my car it would stall ALL the time when rolling to a stop. If you have that, a rich mix and a BOV leak at idle...there is no hope with VTA.
Do you have the evil idle dip? When I had the JRSC on my car it would stall ALL the time when rolling to a stop. If you have that, a rich mix and a BOV leak at idle...there is no hope with VTA.
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From: worcester ma
ok, checked it a bunch today,
bov does not leak while idleing, car idles great
it used to dip a bit when slowing down before turbo, but after flywheel install
it is 9lbs
so im assuming that the rich condition with my normal 800rpm idle combined with my flywheel makes me stall
if i take out the rich condition, say i blow off at 4k and keep it in gear while slowing to a light, and then put it in neutral sat at 2500, then it idles down, dips a bit but catches it self
i have a greddy replacment in my house, ill try that on for a few runs, see what happens,
if problem persists, im going to recirc,
ill tell u guys all about it as i do it,
thanx for all of your help
ps,, cruising home, i let the bov go off next to a scion tc that had his window open
he stared at me all the way down the 2 lane rd
i got a kick out of it
bov does not leak while idleing, car idles great
it used to dip a bit when slowing down before turbo, but after flywheel install
it is 9lbs
so im assuming that the rich condition with my normal 800rpm idle combined with my flywheel makes me stall
if i take out the rich condition, say i blow off at 4k and keep it in gear while slowing to a light, and then put it in neutral sat at 2500, then it idles down, dips a bit but catches it self
i have a greddy replacment in my house, ill try that on for a few runs, see what happens,
if problem persists, im going to recirc,
ill tell u guys all about it as i do it,
thanx for all of your help
ps,, cruising home, i let the bov go off next to a scion tc that had his window open
he stared at me all the way down the 2 lane rd
i got a kick out of it
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From: worcester ma
reddroptop - went with ur advice, option 2, ordered the etd cross over while i wait to install the front mount
it came with the turbosmart bov, i installed everthing and car runs like stock
thanx alot guys
here are some pics
DSCF3230.jpg
DSCF3229.jpg
DSCF3228.jpg
it came with the turbosmart bov, i installed everthing and car runs like stock
thanx alot guys
here are some pics
DSCF3230.jpg
DSCF3229.jpg
DSCF3228.jpg

Hes waaay too busy working on his old *** beater lotus projects to cater to us miata drivers. Afterall, he doesn't even own a miata anymore, sold out to the :gay: front engine porsche club..
Not what I would have personally gone with, but if it works for you that is great.
Thread Starter
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From: worcester ma
cjernigan - i have a greddy type s that ill eventually recirc, but its way too cold to stay outside for longer than a few min at a time
reddroptop - ill prob change this setup 100 times until i find somthing that i like lol
reddroptop - ill prob change this setup 100 times until i find somthing that i like lol







Of course, i had a slightly high idle as well. (~1100 rpm.)