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Did you also install a speed density sensor to properly tune the car for the atmospheric bov? Because a maf sensor based car cant and wont support an atmospheric bov. Are are just throwing random parts on a car to sound cool?
 

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No I was not aware I needed that, I watched a ton of videos and did some research and was unaware tuning was needed.
Where did you do your research? Reddit or facebook? Because this is a well documented thing. Everyone wants to sound cool with a BOV so the girl at the mall knows he drives a turbo'd car. But, the issue is that the maf sensor reads air entering through the intake, the ecu uses this metered air to adjust your AFR. When you install a BOV, it is releasing air from the system, leading to extremely rich conditions when bov activates and discharges the air. Over time this will cause premature engine wear and can lead to failure. Only way to tune for a BOV is by having a speed density sensor. Which is a costly and silly upgrade just to make noises.
 

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Discussion Starter · #7 ·
I am 100 percent catless and it has small pops and crackles when shifting which is absolutely normal. I was wondering about the blow off valve, I have a recirculating Hks which means the air is not leaving the system so I shouldn’t need a speed density kit right or am I still wrong?
 

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I am 100 percent catless and it has small pops and crackles when shifting which is absolutely normal. I was wondering about the blow off valve, I have a recirculating Hks which means the air is not leaving the system so I shouldn’t need a speed density kit right or am I still wrong?
As long as it is recirculating you should be good. But that would make it a BPV, not a BOV. When most people say BOV they mean an atmospheric blow off valve, no recirculating. So as long as you have it set to recirc., you're good.
 

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Discussion Starter · #9 ·
Sorry for the confusion, I’m new to the community but I bought the Hks system and it gives you the choice. I could leave it as a BOV or recirculate it. So I shouldn’t be worried?
 

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Sorry for the confusion, I’m new to the community but I bought the Hks system and it gives you the choice. I could leave it as a BOV or recirculate it. So I shouldn’t be worried?
Nope, as long as you have it set to recirc you are good. But really, it was money wasted because I can promise you that you arent making more power than the stock unit can handle. Regardless, leave it on recirc, and you are good to go.
 

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I'm really curious about the popping.

I know the EJ is a different beast but I couldn't make mine pop without effort. It did the usual burble but a pop means you've got raw fuel and oxygen entering the exhaust.

On a built vehicle where it's fueled for big hp you can see it because of the amount of fuel delivery.

Have you cleaned the MAF or messed with it at all?
 

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Sorry for the confusion, I’m new to the community but I bought the Hks system and it gives you the choice. I could leave it as a BOV or recirculate it. So I shouldn’t be worried?
Read the specs about it, I have seen BOV with options to recirculate that only recirculate a portion of the air, rest is still atmospheric, if that’s the case of your model then you have half of the problem solved. Make sure it is 100% recirc


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I'm really curious about the popping.

I know the EJ is a different beast but I couldn't make mine pop without effort. It did the usual burble but a pop means you've got raw fuel and oxygen entering the exhaust.

On a built vehicle where it's fueled for big hp you can see it because of the amount of fuel delivery.

Have you cleaned the MAF or messed with it at all?
You know the power im making, it will burble every now and again. But when im on E85 and ripping on it, the 3 foot flames from the exhaust when I shift are pretty cool lol.
 
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