Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   Prefabbed Turbo Kits (https://www.miataturbo.net/prefabbed-turbo-kits-3/)
-   -   installed bov, and car stalls when off throttle (https://www.miataturbo.net/prefabbed-turbo-kits-3/installed-bov-car-stalls-when-off-throttle-16056/)

Braineack 01-23-2008 12:10 PM

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:

http://pixyland.org/peterpan/Imagezz...tand_small.jpg

so one only assumed. :bowdown:





compromised.

urgaynknowit 01-23-2008 12:25 PM

im from Europe originally

FHS 01-23-2008 12:43 PM

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.

urgaynknowit 01-23-2008 01:53 PM

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

Braineack 01-23-2008 02:28 PM

basically.

your AFM is metering air, and you're releasing it.

so not only is the mixture off, you have a big vacuum leak while the valve is open.

dirtyboost 01-23-2008 03:20 PM

i vote for no bov!

pschmidt 01-23-2008 04:11 PM

get an adjustable BOV like a GFB or HKS SSQ. You'll be able to crank it down enough to get it to idle properly, but still pop off when needed.

reddroptop 01-23-2008 04:40 PM

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.

Trent 01-23-2008 05:29 PM

Oddly, I ran that DSM BOV on my car for years and never once stalled out. :confused: Of course, i had a slightly high idle as well. (~1100 rpm.)

miataspeed1point6 01-23-2008 05:40 PM

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.

Gotpsi? 01-23-2008 08:05 PM

I have a hks knok off and have no idle isues at all runs great

urgaynknowit 01-23-2008 08:47 PM

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

Bryce 01-23-2008 09:30 PM

FWIW, watching my wideband gauge while cruising on the highway, even the slightest lift will cause it to vent to atmosphere.

urgaynknowit 01-24-2008 03:01 PM

3 Attachment(s)
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

Attachment 214711
Attachment 214712
Attachment 214713

Bryce 01-24-2008 03:09 PM

Looks pretty good, but needs more intercooler.
I have that exact same air filter.

urgaynknowit 01-24-2008 03:45 PM


Originally Posted by Bryceness (Post 204190)
Looks pretty good, but needs more intercooler.
I have that exact same air filter.

thanx, the air filter is an ebay one lol, didnt want to fit in the motor bay,
i made it fit


and ill install the intercooler as soon as its not snowing, and windy and shitty

elesjuan 01-24-2008 04:09 PM


Originally Posted by Braineack (Post 203397)
besides crap out some jb welded shit pipes you may/may not get in this century? oh nothing.

Yeah, so I answered my own question. :)

Hes waaay too busy working on his old ass 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..

cjernigan 01-24-2008 04:09 PM

Hell you can't recirc that valve anyway, what a waste of time. Clean bay though.

reddroptop 01-24-2008 04:28 PM


Originally Posted by urgaynknowit (Post 204185)
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

No problem dude, Glad I could help.

Not what I would have personally gone with, but if it works for you that is great.

urgaynknowit 01-24-2008 05:36 PM

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


All times are GMT -4. The time now is 06:53 AM.


© 2024 MH Sub I, LLC dba Internet Brands