i was talking to the guy who owned the rx7 b4 i did and he said there was a bypass valve that gave it more horsepower is this true.

or am i dumb?ha

 

The only bypass valve I can think of is the Air Bypass Valve or the stock "blowoff" valve on a turbo rx7. It mounts on the air cleaner box and receives a vacuum line from the "air inlet duct/tube" that comes right off of the turbo. On quick throttle release it diverts air back into the box before the AFM so the air doesn't cause turbulence in the turbo.

I'm pretty sure you can route it the atmosphere, but I dunno about power...

 

for future reference, about half the people that say they ever owned an RX-7 have little to no idea what they're talking about (in reference to RX-7's). I know a guy who works at a local parts store who OWNS a 1st gen and he couldn't even remember what 'rotors' are called. you have to be careful, BUT here you are being careful, asking whether your friend is right or not, so good job +1

I've heard that venting the stock bov to atmosphere doesn't give you anything, in fact probably reduces power if anything. the bov releases metered air into the pre-turbo area but is still after the MAF, so the air is still accounted for. if you vent to atmosphere you'd probably run rich shortly after every time you blow off pressure.

There's a bypass air solenoid valve, but that helps with idle under load I believe and couldn't really increase power capacity... I don't know of any other sort of bypass on the stock setup.

 

thanks. yeh i though he was bsing me.

but yeh i dont have a turbo though. i have a n/a vert.ha

 

Not calling you on anything, but how does the stock bav vent to the post-afm area? Wouldn't that meant everybody running atmospheric bovs are going rich after theirs blow off?

Reason why I ask is because I have a FMIC and I'm going back to the TMIC (So I need the stock bov or a flange for an aftermarket) and I plan on using the original bov. I'm going to mount it on the turbo outlet piece and let it go atmospheric like any other bov would. Can I do this?

 

probably. I don't think it's a huge deal, and despite running rich at that point it may do very little to affect power used on the road because of when it happens.

the stock bov vents to the TID, which is after the MAF. I've heard the stock bov doesn't make a good atmospheric bov. you might want to use something else *shrug*

and everyone venting to atmosphere with the stock ECU probably runs rich at that point, standalone systems might have a way to avoid that, but it may even be undesirable or not worth the trouble to adjust fuel delivery when venting intake pressure.

 

It probably isn't rich enough to matter, not to mention better rich than lean. I've heard that the stock bov can handle at most 10 psi and works fine as atmospheric. Like said earlier in the thread, take everything you hear from somebody with a grain of salt. Likewise for this board, tons of people on here believe they are right and make threads about terrible ideas. We are all guilty of it.

 

The stock bypass valve will only work as designed.
If you vent it to the outside, it will leak under vacuum, unless you add a check valve.

Aftermarket BOV's are made to not leak under vacuum.
And yes, an atmospheric BOV will dump metered air which gives a short rich burst in the AFR on gear changes.

Want this one? Send me $20.