Jump to content
SAU Community

Recommended Posts

Where is the best most efficient place to plumb back your bov.

into the front of the turbo or into the exhaust manifold before the turbo?

i cant find many people that have plumbed it back into the exhaust manifold, is there a reason for this?

Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/
Share on other sites

Where is the best most efficient place to plumb back your bov.

into the front of the turbo or into the exhaust manifold before the turbo?

i cant find many people that have plumbed it back into the exhaust manifold, is there a reason for this?

Before the turbo, but after the Air Flow Meter (AFM) or what ever meters the air on the intake side

(in my case, its the map sensor in my Megasquirt, connected to the intake manifold)

Nigel

post-13098-1263973458_thumb.jpg

Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5045353
Share on other sites

what looks like when it is plumbed into the manifold is the external wastegate. very similar in design and operation

the outlet of the BOV needs to vent to an un-pressureised section of the piping, if it is venting to a boosted pipe, it aint gonna do too much at all....

How noddle has his is ideal.

Radiator hose is good for connecting to the outlet of the bov too...

BTW noddle, those hose clamps look tough as... where did you source them from? and what DIA pipe are you useing?

i just orded a stack of 2.5 inch, hope its not TOO big

Edited by MAG86
Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5045492
Share on other sites

external wastegate is plumbed in after the turbo into the exhuasts dump pipe.

what im suggesting is that the vented air from the bov is pushed into the ex manifold so the turbo gets a thrust of air to keep the turbo spooling between changes.

maybe im looking too much into it..

Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5045633
Share on other sites

what happens if you plumb it back before the afm?

my afm is in my cooler piping after the cooler and before the tb?

i was gonna plumb the bov from between the tb and the afm and throw the air into the front of the turbo.

Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5045811
Share on other sites

i think that if an extra puff of air went past the AFM off throttle it would lean out to buggery.

i think do it AFTER the afm... and yes close to the turbine to help keep it spinning

BUT if its a big 'dose' of air it may go back through the afm anyway.... good point you have there...

Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5045934
Share on other sites

Plumbing the BOV into the exhaust manifold IN theory could result in a minor antilag effect, but could(and probably would) cause backfiring due to unburnt gasses receiving a shot of oxygen. the shockwaves inside the manifold would likely sheer the exhaust wheel after a while.

Personally I wouldn't do it, but it could be something to have a play with on a throw away engine...dont use your pride and joy.

cheers

Jason

Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5046168
Share on other sites

what happens if you plumb it back before the afm?

my afm is in my cooler piping after the cooler and before the tb?

i was gonna plumb the bov from between the tb and the afm and throw the air into the front of the turbo.

if I read this right, air filter to intake pipe to turbo to cooler (inter-cooler I assume) to afm to pipe to throttle body

If you put the BOV before the afm and vent it to atmosphere it wouldn't upset anything

"i was gonna plumb the bov from between the tb and the afm and throw the air into the front of the turbo."

if you put it after the afm back to the intake of the turbo or vent it, you WILL have issues with metered air (rich)

my suggestion, move the afm before the turbo, have the bov in front of the throttle, back to turbo intake after the afm (between afm and turbo)

draw a picture of it, you will see what I'm saying

Nigel

Edited by noddle
Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5046274
Share on other sites

i dont fully understand the afm bit, if it gets more air wont it just read it as more air?

its just air.

the more air the afm see, the more fuel it will injected into the engine, ( it only see the air going through it, it has no idea that you have plumbed it into anywhere)

here's a picture, the one with the cross will work, but it will run rich when the BOV opens

Nigel

post-13098-1264055272_thumb.jpg

Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5047385
Share on other sites

the first diagram is what my mate had with his RB30et we built a few years back. moving the afm to AFTER the cooler was the best thing we did...

and nigel... hose clamp details mate! (your bits are getting packaged over the weekend)

Nubco nubco.com.au

looks like they are only a Tassie Firm, how about that, most of the time it a mainland firm that doesn't have a outlet in Tassie..

but I have seen these types off clamps on the net though

the pipe size is,

Pod to inlet to turbo is 3 inch, turbo to intercooler to throttle body is 2.5 inch, turbo exhaust is 3 inch, no cat, muffler at the end just before it comes out the back

Nigel

post-13098-1264071369_thumb.jpg

post-13098-1264071386_thumb.jpg

post-13098-1264071400_thumb.jpg

post-13098-1264071416_thumb.jpg

post-13098-1264071433_thumb.jpg

Edited by noddle
Link to comment
https://www.sau.com.au/forums/topic/304715-plumb-back-bov/#findComment-5047843
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Dunno what to tell you, when I look at it on Consult I can see this warmup timing map kicking in around 40C coolant temp and it sticks around for a while:  At part throttle on the normal base timing map it peaks around ~43 degrees of timing or something like that, this warmup timing map drops it to like 12-15 degrees. 
    • I don't think that's what you're seeing. Something else doing that. The only time I've seen it get so retarded is when it's trying to control idle (in which case we're not talking about mapped timing tagets anyway) and when there is an extreme coolant temperature sensor fault. The RB26 ECU is essentially the same as the 20 ECU and I knew that ging inside out. There is no facility for it to retard that heavily on cold start. The OEMs never used to do it back then. I mean, shit, the catalyst is abotu 3 miles down the exhaust anyway. Early light-off was just a twinkle in some EPA arsehole's eye back then, not a regular engine control strategy.
    • I must preface my comments with a general expression of ignorance. I have no specific knowledge of these NA automtaic things. I can only assume that the "steering wheel button" is for enabling the tiptronic controls. Wierd that it would even need/want a button for that... But anyway.... Was the car previously tiptronic? Did you put a new cluster in as part of all this?
    • Regardless, it doesn't seem wise especially on RBs to actually chase MBT. Timing scatter is the big one on stock CAS, even if that's fixed overshoot is worse than undershoot. 
    • It's all about reducing the overall output. Reduce the source of it, you have wayyyy less to deal with in every other step and trick you play with. It's why something like a modern vehicle, so VW, Audi etc, there's thousands of tables for the ECU to calculate what it should be doing with the engine.   Why would you NOT reduce emissions the most effective way possible, when it has very minimal tradeoff, AND manufacturers are always struggling to meet the current standards.
×
×
  • Create New...