BOV signal source
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OK. I'm a bit confused. I'm looking for where to get the BOV signal from. I was reading the Flying Miata install manual and it states that the BOV should get its signal from the intake manifold (past the butterfly). But I've been reading some forum entries where some of the more knowledgeable members were saying that it should come from a location between the IC and the throttle body (it seems to me that this is the same source as one of the sides of the BOV).
I was under the impression that when the butterfly on the throttle body closes, it creates a vacuum that pulls open the BOV. Otherwise, it sees a boost on that line and keeps the BOV closed.
Is that not the way it works, or am I crazy?
Tony
I was under the impression that when the butterfly on the throttle body closes, it creates a vacuum that pulls open the BOV. Otherwise, it sees a boost on that line and keeps the BOV closed.
Is that not the way it works, or am I crazy?
Tony
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The BOV signal must come from the intake manifold, after the throttle body.
The BOV intake must come from the intake tract prior to the throttle body, preferably after the intercooler.
The Wastegate (or MBC) signal can come from any one of three places:
1- After the compressor but before the intercooler. Easiest to route, but leads to boost dropoff.
2- After the intercooler but before the throttle. Best for a street car- regulates boost very evenly.
3- After the throttle plate. This is for race cars only- the turbo will be spooling like mad all the time.
The BOV intake must come from the intake tract prior to the throttle body, preferably after the intercooler.
The Wastegate (or MBC) signal can come from any one of three places:
1- After the compressor but before the intercooler. Easiest to route, but leads to boost dropoff.
2- After the intercooler but before the throttle. Best for a street car- regulates boost very evenly.
3- After the throttle plate. This is for race cars only- the turbo will be spooling like mad all the time.
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The BOV signal must come from the intake manifold, after the throttle body.
The BOV intake must come from the intake tract prior to the throttle body, preferably after the intercooler.
The Wastegate (or MBC) signal can come from any one of three places:
1- After the compressor but before the intercooler. Easiest to route, but leads to boost dropoff.
2- After the intercooler but before the throttle. Best for a street car- regulates boost very evenly.
3- After the throttle plate. This is for race cars only- the turbo will be spooling like mad all the time.
The BOV intake must come from the intake tract prior to the throttle body, preferably after the intercooler.
The Wastegate (or MBC) signal can come from any one of three places:
1- After the compressor but before the intercooler. Easiest to route, but leads to boost dropoff.
2- After the intercooler but before the throttle. Best for a street car- regulates boost very evenly.
3- After the throttle plate. This is for race cars only- the turbo will be spooling like mad all the time.
In the photo below you see a DIY hot side intake/BOV intake adaptor (came in the used kit I bought) I also notice that there is a plug in it currently. Would I be best to take the WG signal from that plug as in example #2 above? I can just stick an adaptor with a nipple in there.
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Can you also tell me if this is the proper signal for my boost guage (blue line with the white T-fitting) and which one of these other lines can I use for the BOV signal?
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I have the FM intake tube and that is where I stuck my stock IAT sensor. Is that correct or does it fuel better on the hot side. I guess I just answered my own question as I thought about that sentace - the actual air getting combusted is the hot side air so the fueling amount/timing should be relative to that correct? If so why does FM have that location for the IAT is it for cars withou IC's ?
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If so why does FM have that location for the IAT is it for cars withou IC's ?
Where do FM and BEGI place the factory IAT then? I mean am I safe doing it this way, I guess I would have richer A/F's having the IAT in the cold side than in the hot side so at least Im safer for now until I figure out my next move.
What gains will I see by placing it in that hot location, 1 or 5 or more % more hp? I'd rather be safe right now as it's all new to me.
Can I still run the WG signal there - is that preferred ?
I do remember way back reading about a GM IAT is that one threaded - I'll do some searching?
Where do FM and BEGI place the factory IAT then? I mean am I safe doing it this way, I guess I would have richer A/F's having the IAT in the cold side than in the hot side so at least Im safer for now until I figure out my next move.
What gains will I see by placing it in that hot location, 1 or 5 or more % more hp? I'd rather be safe right now as it's all new to me.
Can I still run the WG signal there - is that preferred ?
I do remember way back reading about a GM IAT is that one threaded - I'll do some searching?
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So BEGI puts the stocker in their cold air box i see.
Looks like you all prefer locating it in the IC piping after the IC. I think I'll get the car running then decide on a GM IAT later.
Thanks for identifying that bung/plug I had no idea.
Looks like you all prefer locating it in the IC piping after the IC. I think I'll get the car running then decide on a GM IAT later.
Thanks for identifying that bung/plug I had no idea.
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If you put the IAT in that bung, it will be sitting behind the radiator and will get heatsoaked like a ****. You'd be better off leaving the WG reference on that bung like you have it and drilling a new hole for the IAT that's in the end tank of the IC itself, or in the piping after the IC, somewhere not directly behind the radiator so it's not getting blasted with hot air all the time.
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Are you kidding me, have you not been to Canada. How do you think we pay for all that A/C to keep it so cool up here, that money has got to come from somewhere! It comes in the form of everthing you buy down there add 50% - 100% up here.
If I buy the IAT then I have to but a tap for the IC which means I have to drive to the store so now that $22 part is $136.54CDN dollars.
Allright I had no idea they were that inexpensive. I still need to get rid of my stock exhaust first and believe me up here a 3" exhaust is not cheap.
If I buy the IAT then I have to but a tap for the IC which means I have to drive to the store so now that $22 part is $136.54CDN dollars.
Allright I had no idea they were that inexpensive. I still need to get rid of my stock exhaust first and believe me up here a 3" exhaust is not cheap.
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