Bov
- Thread starter smp3000
- Start date
K
Keith@FP
Remember that your car's ECU is calculating the amount of fuel to add based on the air it measures through the airflow meter. If you vent some of that air to atmosphere, it doesn't know. Thus the use of a recirculating BOV in the BEGI kits. Some BOVs (like the one included with your kit) will leak a little at idle, so you insist on venting to atmosphere make sure you don't have one of those.
If you all you need is the noise, there are electronic BOV noisemakers on the market
Keith
If you all you need is the noise, there are electronic BOV noisemakers on the market
Keith
Ya I went with the Greddy Type S. That was the product everyone seemed to recommend. Plus I got a pretty good deal on it.
I've heard both the pro's and con's on both recirculating valves and BOV's. I couldn't really see one or the other being "better" persay for my situation. But at least this way it'll help get rid of lag and will make me sound like I'm much cooler than I am, hehe.
I've heard both the pro's and con's on both recirculating valves and BOV's. I couldn't really see one or the other being "better" persay for my situation. But at least this way it'll help get rid of lag and will make me sound like I'm much cooler than I am, hehe.
K
Keith@FP
There's no functional difference between a recirculating BOV and a vented BOV. The recirculating one is friendlier for stock ECUs and quieter, the vented one is noisier and easier to plumb in.
Keith
Keith
keep the recirculating valve.......if you want a nice sound go with an external wastegate and vent that into the atmosphere. You can here the turbo spool from a block away and it doesn't take away from the performance of the car like the vented bov does
I know you already made your choice, think of this info as to benefit future readers
I know you already made your choice, think of this info as to benefit future readers
A wastegate can still take away performance. However, neither type of BoV (recirc or vent) makes much of a difference for our turbos (as Keith stated). There are always trade-offs with turbos. If you dont blow off, you can lose some turbine rotation, and damage the turbine after extended use (the forced air has nowhere to go but back in). On the other side, while you are allowing the turbine to spin more freely (and save the blades) by venting, you are losing any accumulated psi. The engine is a closed circuit, and if you dont blow (during a shift, say), some of that pressure can stay in the circuit. With a quick-spooling turbine and no waste, you can actually REDUCE lag.mp3_moran said:
If you use a recirc BoV, you can keep a nominally larger amount of psi than with vented. Overall, what you want is waste control, either through a 2- or multi-stage BoV, or a controlled "smart" BoV or wastegate.
But hey, I cant even put a turbo on yet, so I just salivate at all you lucky dogs who've got em (guess I cant say s****). As always,
Happy Hunting!!!!!!!!!!!!!
K
Keith@FP
Our opinion is that a BOV of some sort is required for a good turbo install. The compressor stall is a bigger problem than any loss of "accumulated psi". We recirculate on some of our kits and vent to atmosphere on others, depending on the engine management system used.
Keith
Keith
We have had experience with 2 turboed Pros. It seems to appear that certain bov's that vent into the atmosphere work fine with our MAF'S and some do not. Amongst these that work are the HKS SSBOV and the Greddy Type s. We tried the apexi twin chamber and idle droop occured. I possibly think that some of the bov's leak causing a bad idle droop. Or you can go for the sleeper sound and vent it back into the intake....... bahhhh........thats for foggies
I prefer the trumpet of boost exclusivity
my 2 cents
I prefer the trumpet of boost exclusivity
my 2 cents
K
Keith@FP
Sorry, I missed this the first time. Wastegates and BOVs are different things, designed to address different problems.
A wastegate controls the amount of boost a turbo generates by bleeding off excess exhaust gas once the set limit is reached. All turbos have wastegates. Some are integral and part of the exhaust housing, some are external and plumbed into the manifold. External ones can be vented to atmosphere or into the exhaust. Internal ones go back into the exhaust stream.
A BOV vents excess pressure when the throttle plate is slammed shut, bouncing a wave of pressure back into the turbo and stalling the compressor. A typical scenario is a shift. BOVs are not included in all turbo installations, but they really do make a difference. They can be vented to atmosphere or to the intake, as I mentioned earlier.
Some BOV designs do leak, and therefore can cause problems at idle if they are vented to atmosphere (ie, sucking in unmetered air) and there is an air meter of some sort in the system. It's a matter of design of the BOV.
Keith
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