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I'm not very good with all the little things with engines such as BOVs. I have a couple of questions before I start my NA to 3rd gen 3SGTE Swap.

1. What piping does the BOV connect to?

2. Do aftermarket BOVs give performance?

3. Do aftermarket BOVs give the same fluttery sound as the OEM BOVs (Love the Flutter on the stock BOV)?

Thanks in advance!!!
 

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1. The intercooler piping immediately after the turbo, as well as a vacuum reference line (can use the stock vacuum line)
2. No, not really.
3. No, more of a whoosh sound
 

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BOV really just keep the turbo spinning after let off the throttle... if it blows into the atmosphere that’s when you really hear the woosh... unless you have a MAP sensor (94-98) that’s really the only way you can run open...’if it’s a AFM (90-93)setup then it has to get Plummer into the IC tube or The ecu will see it as Un-meteor’d air and it’ll run like ****.... this help??
 

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Yes it will “fit”.. I have the same thing and it was a smij off on the driverside, I just took a 2” metal plate and drilled two holes... they work great and more than half the price
 

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My first MR2 was a 93 turbo, had the MAF.
I put a Apex BOV on it (my car was red, it had a red ring on it lol, plus it's a very reputable brand)...while I liked the sound, as stated above, it changed how it ran.

So youre boosting along, the air coming into the filter, through the MAF and the ECU knows how much air is in the system and how much fuel to dump in. When you get off throttle the air rushes out, but the fuel is still getting dumped in.
So it runs rich for a second and CAN (and DID) stall the car out.
I got good at blipping the throttle to introduce more air and 'even' it out a bit, but it's tricky when pulling up to an intersection or something and getting the little blip in.

While I liked the sound, dont know if I'd do it again.
My Gen3 swap doesnt have this issue, and has stock bpv (bypass valve), and still gives a sweet little sound, but nothing as loud as a BOV would. But im pleased

There are NO performance gains to be had, to my knowledge
 

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No gains at all, unless your drag racing and have two haha... on my last car I had an HKS T51 Kai turbo setup and didn’t even run a BOV.... never had any issues...
 

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Every car might sound differently, depending on the deviation from stock. I have no BOV at all (GT3040/3082 has had no issues since 2003 and never rebuilt), and it is my absolute favorite sound... it's like a dragon breathing and the craziest flutter sound, like a flute. Nothing is stock, 5sgte... but it sounded similar with previous 3sgte bottom end, and with variations in the exhaust manifold and 4" exhaust as well. The size/type/nature of your intake tubing, intake manifold and IC, and IC location will have the most dramatic effects on intake sound, regardless of BOV or not. Thicker, heavier materials like heavy oem cast stuff will be much quieter, whereas thin-wall aluminum tubing will translate the most sound. Some versions of the 3sgte were actually silent without a bypass valve from factory, and so came without any from Toyota. This lends to the assumption that bpv's were largely for intake noise suppression.
 

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^^ best post so far. Loads of debate on the subject and I reside firmly in the BOV delete camp. Why lose all that energy for a bit of noise? Been running without a BOV for 6 years now without any issues at all. Best sound is hearing the turbo do it’s work.
 
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