howto: bypass stock bypass valve

[topher91]

Hey guys,

I've installed another BOV on my sr20 but I need to block off or bypass the stock bypass vavle that is on my car.

Hey Laurier, I think this is why the SARD bov wouldn't work either?? :confused:

Oh and will there be anything that would cause the car to run poorly becuase of the new BOV venting to atmosphere instead of recirculating??

The bov valve is located just before the stock SMIC and after the MAF (I think) so would it cause a problem??

:dunno: :dunno: Help!!

TIA

CHris

[dymz999]

won't cause any problems. Removing the stock bypass valve? you dont have to remove it actually, keeping it in there will not do anything. It will still function normally. The open atmosphere blow off valve will just make you loose a bit of gas mileage is all.

Recirc setups can be good in some circumstances. The only thing you need to get used to with open atmosphere is that if your going 80km/h and need to come to a stop your car can and will stall if you dont two foot the stop, bit of gas and a lot of break. It will keep the engine idling nicely.

I got sick of my recirc setup last year.

[R-Audi]

By not re-circ your BOV you will run rich after you shift. The ecu is excpecting the air to be back in the system, and supplies fuel on that assumption. Not a terrible thing, but not great for performance and gas consumption. In instances like above the car can stall.
Even being re-circ. you should still get the noise although not as loud. My feeling is the car is designed that way, so why change it?

[topher91]

ok so HOW do I remove the stock bypass valve?? Or is there even one??

[dymz999]

If you take the vacuum supply off of it it will eliminate the stock by pass. then take that vacuum line and hook it up to the new blow off valve.

That should get rid of it, it will still be there just no longer functioning. It is located in the piping that runs right into the intercooler. Then again i've never used a SMIC, but thats where it was on my front clip :)

[topher91]

Nick at Speedtech said it should be behind the SMIC and that I can just block it off with some rubber plug that you can get at crappy tire. But if I can just take that vaccum line off and that will do the trick, that is wayyyyyy easier!

[dymz999]

take the vacuum off and it will not open or it shouldn't. the rubber plug idea is if you are using a greddy Front mount kit. if you just plugged the recirc valve you'd have a hole sitting in your intake piping. Quite honestly if you want I can come to your place and check it and out and make some custom piping for your intercooler setup, would be way cleaner and nicer looking and wouldn't cost overly too much.

But its not as simple as just removing it since it is connected back into the turbo and such.

I can post some pics tomorrow of the custom piping i've done on a few cars. I tend to use polished stainless steel since it just looks nice.

[topher91]

Originally posted by dymz999
take the vacuum off and it will not open or it shouldn't. the rubber plug idea is if you are using a greddy Front mount kit. if you just plugged the recirc valve you'd have a hole sitting in your intake piping. Quite honestly if you want I can come to your place and check it and out and make some custom piping for your intercooler setup, would be way cleaner and nicer looking and wouldn't cost overly too much.

But its not as simple as just removing it since it is connected back into the turbo and such.

I can post some pics tomorrow of the custom piping i've done on a few cars. I tend to use polished stainless steel since it just looks nice.


Well I don't think I need custom piping for the stock SMIC, but when I go FMIC you can help me out for sure then!! I tried to get to the intercooler but find that I have to remove my wheel to get to it.

I only wanna bypass the valve as the BOV won't go off at all, or is there another problem I should be looking at??

Chris

[dymz999]

Do you still have the black fiber crap inner wheel well there? If you do you can jack the car up and get to it from the bottom since that is actually where it is located. you can get better access to it from the bottom if you still have those inner wells in.

The good thing about custom piping if you ever want to do it is that i can create a blow through MAFS for you. aka put the MAFS on the cold pipe to prevent any stalling. This is how i have my Z32 MAFS done...

Did you disconnect the vacuum source to the recirc valve? When you do that it should stop it from opening. If you cant get to the source on the blow off valve just take the source out that comes from the intake and run a new line to the blow off valve. It will work if you can't get to the recirc valve. It is in a shitty location from what i remember. Just look for this thing that is big and round and ugly and has one inlet and one outlet, it's a can't miss...

[topher91]

OMG, just pulled out my SMIC to find that there is no bypass valve back there!!!! :eek:

SO WTF?? I have an external wastegate on my T25, can I disable that somehow by also removing the vacuum line from it?? Or is it not recommended to disable the wastegate??


ahhhh!!!!!!!!!!!!!! :banghead:

Chris

[dymz999]

how do you have an external wastegate on your T25? That would be a huge waste on a T25 lol.

Check the hotpipe there has to be something there that would show if the recirc was taken out or not. Also check the rubber itnake pipe going into the turbo. there should be something that has been changed or blocked off. Check to make sure.

Cuz you said the other blow off valve you put in wasn't working right???

[topher91]

Originally posted by dymz999
how do you have an external wastegate on your T25? That would be a huge waste on a T25 lol.

Check the hotpipe there has to be something there that would show if the recirc was taken out or not. Also check the rubber itnake pipe going into the turbo. there should be something that has been changed or blocked off. Check to make sure.

Cuz you said the other blow off valve you put in wasn't working right???


ok so I'm not sure if its an external wastegate. I thought it mite be a wastegate cust there is an actuator bar that goes from the back of the turbo to the front that is attached to a disc shape thing that looks like a bypass vavle. There is a vacuum line that is connected to the top of that bypass looking thing (maybe I should try to get a picture). The line goes right to the intake right after the cone filter and MAF.

But ya, when I looked at the SMIC, it looks like that's how it was like it wasn't modified or anything. There is no other lines coming off the hotpipes or the intake that looks like it was removed.

I'm soooo lost now.......I dun know much about these motors as this is my first non honda!!! :D

I'll get some pix by tomorrow nite to show you that wastegate thingy...... :banghead:

And yes, the BOV I installed doesn't work yet.

Thanks for all the help so far dymz999.

Chris

[^SkylinE^]

LOL sounds like you need a turbo 101 class. take the vac line off your old BOV that will disable it. put that same Vac line on your new BOV. If your car is turbo it will have a BOV, also i sounds like your have an internal waste gate. what ever you do DO NOT DIS CONNECT THAT VAC LINE. YOu need to be careful because your waste gate and BOV are critical to not over boosting and preventing compressor surge. If you need a hand get someone on beyond to help you out or go to a meet and get a hand. take some pictures and im sure we can help you out in locating what you need!:thumbsup:

[dymz999]

Well its not a wastegate, its an actuator. That is all that is.

The recirc valve has to be there somewhere unless the tard in japan disconnected and was running without a recirc. Something I haven't seen since the wonder company named dodge created the turbo shadow.

None the less if you want i can come by and help you out with it. Will likely only take me 5 to 10 mins to figre it out for you. Nissans are a breeze for me :)

[topher91]

Here is the pic of the intercooler piping. Just one tube down and one up. There was no other tubing coming off the ones that are there.

http://memimage.cardomain.net/member_images/9/web/357000-357999/357313_29_full.jpg

[topher91]

and here is the wastegate. Can someone explain to me what the difference is between internal and external wastegates?? My guess is this was an external ????

http://memimage.cardomain.net/member_images/9/web/357000-357999/357313_30_full.jpg

[topher91]

Here's another angle. Now you can see where the actuator is attached to the turbo.....
http://memimage.cardomain.net/member_images/9/web/357000-357999/357313_31_full.jpg

[topher91]

Oh yea....I forgot to mention that when I release the gas, there is a fluttering sound...??? What makes that noise cuz I know that my BOV isn't working, the BOV I have isn't supposed to flutter...?? :confused: :confused:

[dymz999]

That is an internal wastegateg turbo because the wastegate is actually inside the turbo. There is a small flapper that is the wastegate. The actuator in the picture with the arm controls how much the flapper (wastegate) is opened and closed and thus controls boost levels.

[dymz999]

can you get a pic of what is under the two pipes in that picture aka where the SMIC is installed???

also i pm'd you my number so you can call me saturday around errr 10am or 11am and i can come by and help.

There is a recirc if you hear fluttering...

[topher91]

Originally posted by dymz999
There is a recirc if you hear fluttering...

Thats what I thought.... :D

And no, I can't get behind there w/o removing it again. There is some sort of funnel that runs from the front of my front bumper in the grill to the intercooler where its kinda sealed around the whole of the intercooler.

[dj_honda]

the fluttering sound is probably compressor surge, due to your bov not opening.

when we did gpomps car, i remember the bov wouldnt open and the car would make a fluttering sound due to compressor surge with the spring he had in there, so we had to trim it.

[dymz999]

the fluttering sound is likely the recirc valve. it is what they sound like when they let air go by in that little rubber tube lol. It sounds well lame all in all. Call me saturday k and i can fix you up!!!

[topher91]

OK OK..... :thumbsup: :thumbsup:

Thanks for all the help guys!! But I stopped by Speedtech after work and my Knight in shining armour (Nick @ Speedtech) figured it all out for me.

He also wanted me to let everyone know that he did in fact bleed for me as he sustained a minor cut while helping me out.... :(

NOW, no more fluttering sound except while at very low boost after releasing the gas. I don't know if there really is a recirc bypass valve anywhere cuz we couldn't find one.

What we did was change where the vacuum line was sourced from. Before I had it right after the intercooler, then Nick said we should move it closer to the intake manifold. Then like magic the BOV was pshhhhhh-ing !!! :clap: :clap:

Thanks again Nick and to all the guys who tried to help me out!!

Chris
This issue is :closed:, now for a MBC...... is 1 bar safe??