Aftermarket bov

[derbeck]

If you want the car to have a blow off valve you can install a map sensor and ecu this works because it reads manifold absolute pressure so it's reading the pressure not the amount of air that passes it and you won't get the rich points or stalling

[Evans]

relocate the MAF to the opposite side of the throttle body? all jokes, that wouldn't be beneficial at all.

[Skym]

EIDS can help to stop engine overfueling and stalling when deaccelerating.

Look at the PDF above, as it shows the 2x screws (I said knobs) and what they do. One screw adjust's rich / lean and the other screw for how long (time).

[BongRips]

So if you get the HKS EIDS, that'll make an atmo bov stay closed at idle? Because I noticed that when I put on an aftermarket atmo bov, either it will be closed on idle but not open under boost and cause surge (just tried stand still rev so I didn't get huge amounts of vacuum) or it will stay open on idle and once I rev, or drive, it will close and open at the proper time when I shift but sometimes stall out while de-revving

[Ghost]

AKA a .50 cal... as i like to call em... makes people at bus stops jump or duck sometimes... *giggle*

[redrocket]

I'm not too knowledgeable on this with Skylines, but I don't see how that would create a rich condition. Even when it's recirc'd it's plumbed in after the MAF, so it's unmetered to begin with. I know that's the case (rich at shifts) with Subaru's and many other newer cars, but I don't really see how a BOV could cause a rich condition with the Skyline's engine management. I could be wrong though.

exactly it is plumbed in after the maf that means that the ecu just assumes the extra air will be there and doesnt correct anything when you stop putting that air there (fitting and atmospheric bov) so it really doesnt make the ecu put more fuel into it, it just puts the same amount in and you are physically tricking the system into getting less air on the shift by stopping that recircing air from re entering the system that assumes it will be coming. thats why when you shift you might get a *BANG*, or a pop and a flame

[Ghost]

Not all turbo'd cars have this issue, just cars with MAF's.
Yes, a tune helps get rid of it. And it is hit or miss with MAF cars without a tune.

Most tuners doing high hp builds get rid of any sort of blow off valve, thats why you hear the high hp supras and skylines flutter (wututututu) when they let off the gas/shift. The turbos they use can handle it.

Thanks for elaborating, I did forget to mention MAF factor, Grrrr. Kinda posting in the fly via phone kinda pain to type long explanations. :P

[quadracer111]

I'm not sure I understand your first sentence, but BOVs from factory are recirced for a reason...with recirc you dont get off throttle shuffle.

I meant that running no blow off valve or no recirculating valve on a skyline with a ceramic turbo is not smart. Sorry about that lol.

If run a atmosphere BOV, HKS created a device (EIDS) to reduce the rich condition when rpm needle returns to idle -

http://www.hksusa.com/products/?id=2175

Has 2x knobs you adjust on HKS EIDS -

http://www.hksusa.com/content/pdf3376.pdf

I had no idea they made something like this.

[Skym]

If run a atmosphere BOV, HKS created a device (EIDS) to reduce the rich condition when rpm needle returns to idle -

http://www.hksusa.com/products/?id=2175

Has 2x knobs you adjust on HKS EIDS -

http://www.hksusa.com/content/pdf3376.pdf

[johnZ32]

i have a hybrid atmo/recirc. sounds awesome because of the atmospheric portion, but doesn't screw with my idle/fuel dump as much.

[Tairance]

I'm not sure I understand your first sentence.

Im in the same boat^

Alot of good information here though, You guys have helped me out alot. I'm still holding off on the BOV install till I clear some thing up. I hear alot of people adjusting the springs.. I might try this or I think ill just run factory because at high RPM's it still gives off a "woooossh" when shifting and i'm not that large of a ricer I need the entice city hearing my BOV lol.

But thanks guys, You have really helped me and please keep the info coming!

[DarkCaporaL]

No type of recirc valve/bov on a skyline isn't smart. Most have ceramic turbos... They like to shatter.

I'm not sure I understand your first sentence, but BOVs from factory are recirced for a reason...with recirc you dont get off throttle shuffle.

[quadracer111]

This us true with almost all turbo'd cars. My Subaru backfired every so often wih an ssqv on it, it happens. Once tuned it's easier to manage the air fuel ratios a bit better and help eliminate he frequency of excess fuel dump/ backfires... But not eliminate it completely. At higher hp builds I believe going atmospheric is almost a must, not 100% sure on that.

From what I've seen so far with BoV's on skylines it's very hit or miss. Some seem to run fine with them while others seem to stall alot and idle/ RPM weird. It took a bit, but once I got he spring tension adjusted properly on mine, everything worked out just fine. The odd backfire will happen, it's not uncommon on any turbo'd car to do once going ABoV, and doesn't cause damage as far as I know.

But don't quote me on that I'm no guru by any means.

Not all turbo'd cars have this issue, just cars with MAF's.
Yes, a tune helps get rid of it. And it is hit or miss with MAF cars without a tune.

Most tuners doing high hp builds get rid of any sort of blow off valve, thats why you hear the high hp supras and skylines flutter (wututututu) when they let off the gas/shift. The turbos they use can handle it.

[Ghost]

No type of recirc valve/bov on a skyline isn't smart. Most have ceramic turbos... They like to shatter.

Yeah, the MAF meters the air, then it is released before it gets to the engine, so the ecu dumps fuel that isn't needed causing a rich condition.

This us true with almost all turbo'd cars. My Subaru backfired every so often wih an ssqv on it, it happens. Once tuned it's easier to manage the air fuel ratios a bit better and help eliminate he frequency of excess fuel dump/ backfires... But not eliminate it completely. At higher hp builds I believe going atmospheric is almost a must, not 100% sure on that.

From what I've seen so far with BoV's on skylines it's very hit or miss. Some seem to run fine with them while others seem to stall alot and idle/ RPM weird. It took a bit, but once I got he spring tension adjusted properly on mine, everything worked out just fine. The odd backfire will happen, it's not uncommon on any turbo'd car to do once going ABoV, and doesn't cause damage as far as I know.

But don't quote me on that I'm no guru by any means.

[quadracer111]

I decided to cheap out on a BOV and just unhooked and blocked the recirc hose. I was having terrible idle and stalling all the time. I quickly hooked everything back up. I just bought a blitz bov. Is this going to happen when I install it too? What was the reason?

No type of recirc valve/bov on a skyline isn't smart. Most have ceramic turbos... They like to shatter.

I'm not too knowledgeable on this with Skylines, but I don't see how that would create a rich condition. Even when it's recirc'd it's plumbed in after the MAF, so it's unmetered to begin with. I know that's the case (rich at shifts) with Subaru's and many other newer cars, but I don't really see how a BOV could cause a rich condition with the Skyline's engine management. I could be wrong though.

Yeah, the MAF meters the air, then it is released before it gets to the engine, so the ecu dumps fuel that isn't needed causing a rich condition.