Recirculated my BOV, still stalling at lights and stop signs

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rn240sx
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Recirculated my BOV, still stalling at lights and stop signs

Post by rn240sx »

Well, after everyone insisting that my stalls were due to open atmos bov, i went and recirculated it back to the turbo intake and im STILL STALLING out..!!

That was a waste of $30...

Anymore suggestions..??
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98 240sx KA-T Full built motor JWT ecu 60-1 turbo 10 lbs
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Post by Jordan Gladman »

Raise your idle.
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Post by 89NoSwap »

Put your BOV on the hot-pipe side.
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Post by doggunracing »

It helps to point the BOV re-entry toward the turbo, so it doesn't backflow into the MAF.
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Post by rn240sx »

Ok, after months of searching i found out from others that the entry method for the bov going back to the intake side does not matter.

It does matter for the wastegate entry back to the exhaust stream. I had it 1st routed into the exhaust stream at a 90 degree angle and it caused boost creep. I then changed the entry to enter at a 45 degree angle and the boost creep was gone..!!

Now, im not sure if this goes true for the bov re-entry... Maybe it does matter, maybe it doesnt. All I know is that everyone was saying to recirculate it to cure this stalling problem. I did and im still stalling out..!!

Also i was told that mounting the bov on either side will not effect the stalling as long as it is recirculated..!!! On my previous S14 i had the bov mounted on the same cold side, OPEN bov and never stalled out..

One other guy told me that since i have the asp pulley and the fidanza flywheel and WITHOUT the mechanical fan the rpms will drop faster than normal giving the motor a higher chance of stalling out.

I guess i will raise up the base idle to about 900-1000 to see if that cure's. Also one other guy that i know is running open bov and all he did was raise his idle to 900 rpm and he has NO stalling problem when comes to a light or stop sign.
www.shopboldimpressions.com
98 240sx KA-T Full built motor JWT ecu 60-1 turbo 10 lbs
14 Genesis Coupe 2.0T stock turbo w/Bolt ons
98 Supra MKIV stock twins w/Bolt-ons
2012 Frontier V6, 4-door, 6ft bed (Daily Driver)
09 Ninja ZX-6R, Full exhaust, K&N pod filters
06 Suzuki Boulevard S40
/\ all still current 8.30.20
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Post by doggunracing »

I think the idea is to get the recirculation as close to the compressor as possible and as far from the MAF as possible. The thinking is that the BOV flow could backflow into the MAF and give a reading for airflow, pump extra fuel, and die. Since you want the air to go towards the compressor, I just aimed mine that way to be safe.

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Post by rn240sx »

UPDATE:
I raised the idle to 1000 rpms and that did NOT help. The motor still stalled out.

A guy on freshalloy wrote me a nice PM telling me what my problem was. The problem IS the bov dumping to atmosphere. So I asked him WHY is it that when i recirculated the bov it did not help. Well, simply because i am running a Greddy Type S.
The greddy type S will only work properly if used as an OPEN dump bov. If it is routed as a recirculation type bov, it will not WORK properly.
WHY...?? I dont know, im still waiting on his explanation.

So, in order to run the type S as a recir bov it needs to be INTERNALLY modified. Basically open it up and REMOVE the inner (smaller) spring and put it back together. NOW, its set to run as a recir bov..

Well i did that and now my car does NOT stall at all......!!!!!!!!
I reved it to about 6k rpm at idle, and the rpm dropped and STOPPED at 800 rpm and maintained solid. I did this about 5 times in a row and it worked 5 times...

I then took it out for a test drive. I hit 5 stop lights and about 6 stop signs. it did NOT stall one time..!!!

During the test, i did notice that the rpm now drops SLOWER than it did b4. Before it dropped quite FAST and then stalled out.. And now when i am under boost and shift gears, im back to 15 psi almost instantly... Now i dont have to build up that pressure that i dumped to atmosphere. Man it felt GOOD...

The only down fall is that now i CANT hear the bov blowing :(
Its quiet now during shifts :(

I dont understand why NOW i have to recirculate it to keep this motor alive when i come to a light or stop sign... When this same motor was in my previous S14, i ran open bov and didnt have these stalling problems.
Maybe its due to the upgraded fuel system or the dual 248 cams i put in, or maybe its due to the upgraded jwt prog... Something now is more sensative and needs more attention..... ??? Who knows...

ITS FIXED AND IM HAPPY :)

Lets see how long it holds for....
www.shopboldimpressions.com
98 240sx KA-T Full built motor JWT ecu 60-1 turbo 10 lbs
14 Genesis Coupe 2.0T stock turbo w/Bolt ons
98 Supra MKIV stock twins w/Bolt-ons
2012 Frontier V6, 4-door, 6ft bed (Daily Driver)
09 Ninja ZX-6R, Full exhaust, K&N pod filters
06 Suzuki Boulevard S40
/\ all still current 8.30.20
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Post by nissanfanatic »

Cool. I'm running a Type S anbd mine doesn't stall but it does drop to about 500. Keep me informed on the BOV mod. I was just assuming the MAFS was double metering air that was being recirculated. Thanks for the heads up.
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