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Comparison of turbo to supercharger

when you close the throttle plate to shift the air thats at the throttle plate has to go somewhere, that somewhere is backwards towards the compressor. the whole point of a BOV (or bypass) is to get rid of that extra air moving backwards so it doesnt get to the compressor causing the compressor to surge. by putting the BOV before the MAF the air now has to go backwards through the MAF to get to the BOV.

Im not confuesd on how yours is setup. the position of the BOV relative to the MAF has nothing to do with wheather its a blow through or draw through setup though. there simply isnt room after the MAF on your setup for a BOV so i understand why you put it where you did, its just not recomended to do so.
 
Chris (blackcoog) talk to Eternalone, I know he was exploring something like that.
 
striker2 said:
when you close the throttle plate to shift the air thats at the throttle plate has to go somewhere, that somewhere is backwards towards the compressor. the whole point of a BOV (or bypass) is to get rid of that extra air moving backwards so it doesnt get to the compressor causing the compressor to surge. by putting the BOV before the MAF the air now has to go backwards through the MAF to get to the BOV.

Im not confuesd on how yours is setup. the position of the BOV relative to the MAF has nothing to do with wheather its a blow through or draw through setup though. there simply isnt room after the MAF on your setup for a BOV so i understand why you put it where you did, its just not recomended to do so.
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Actually having the BOV before the MAF or a BOV at all means it's a blow through. You can't put the BOV anywhere else on a blow through setup. If you put it after the MAF, which I could have if I really wanted because I do have room, it would be dumping metered air and the car would run very rich every time the BOV went off. The BOV before the MAF on a draw through system wouldn't do much good because it would be before the compressor. So saying the BOV is before the MAF could only mean it's a blow through system.

I understand what you are trying to say about the air backing up when the throttle plate closes but I'm not so sure air actually moves backwards through the system. As soon as the throttle plate STARTS to close the BOV opens and all the air that is trying to rush in isn't going to back up because it will be dumped before it gets to the MAF. The air already there is still moving into the engine because the IAC is pulling air in to keep the car running. Either way my car runs the same with our without the supercharger on it. I'm monitoring a wideband and the air/fuel still looks perfect so there are no ill effects of the blow through setup that I can find.
 
i guess thats technically true cause any other setup you have to have a bypass valve and recirculate the air instead of just dumping it.

as for the MAF if the air doesnt move backwards then it will be fine. if it does at least its running good and strong. either way im curious as to the life of the MAF. hopefully it wont be effected.
 
striker2 said:
i guess thats technically true cause any other setup you have to have a bypass valve and recirculate the air instead of just dumping it.

as for the MAF if the air doesnt move backwards then it will be fine. if it does at least its running good and strong. either way im curious as to the life of the MAF. hopefully it wont be effected.
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I don't see why a momentary flow of air over the MAF with a closed throttle valve would be a problem anyway. The throttle is closed, so if anything the mix would be only slightly rich for an instant. Not a biggie, I would think.
 
TourDeForce said:
I don't see why a momentary flow of air over the MAF with a closed throttle valve would be a problem anyway. The throttle is closed, so if anything the mix would be only slightly rich for an instant. Not a biggie, I would think.
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The computer does have a method to smooth the airflow readings anyway. There is always bits of reversion that are present from valve overlap when the engine is running.
Combine that with what you stated above and I agree it would not be something to worry too much about.
 
TourDeForce said:
I don't see why a momentary flow of air over the MAF with a closed throttle valve would be a problem anyway. The throttle is closed, so if anything the mix would be only slightly rich for an instant. Not a biggie, I would think.
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its not so much what it reads as the problem as it is that MAFs dont like having air going backwards over the sensor. it likes one way airflow.
 
striker2 said:
its not so much what it reads as the problem as it is that MAFs dont like having air going backwards over the sensor. it likes one way airflow.
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Define "likes." Are you implying some kind of potential damage to the thermistor or something? I don't think so.
 
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i have heard and seen MAFs go bad from having air move backwards over them. now its not real common but it does happen.

however all the ones i have seen were from GM, i have yet to see a Ford MAF have that problem so it may (hopefully) be just fine.
 
It's nothing more than two wires in an airstream. I don't think they care which way the air is flowing. Only potential problem would be calibration issues with upper/lower wire or differences in inlet/outlet aperture & configuration. Big difference in configuration in our cars, but still, the only problem would be calibration for the airflow in that direction - and that would be momentary at best and have near zero effect on things.
 
The only way I could see the MAF going bad from the slight bit of reversed airflow is if some of the air contained any oil (from the PCV). Since my intake tube has never had residue inside it, I don't think this is a problem. Besides, you should regularly clean your MAF anyways.
 
yeah or dyno slips at the same amount of boost. id like to see the TQ curve to which is going to suit my needs better since i dont like to run past 5 grand
 
maybe each type of setup can talk about emissions with their product and is how it's relates to the limitations of each setup? there are obviously people on the board where this is a major concern.
 
Yes.. he did ride in it.

YamahaRacer: If you don't plan on running past 5K rpm, then I don't REALLY see where the choice is. This is taking the MAJOR DIFFERENCE in power output, and powerband and negating them. If you aren't going to go over 5K, you will need to get all your power before that. a SC is RPM driven, making MAX HP at MAX RPM.
 
lol, acutally i rode in it at our first meet at the Varsity. And at nopi.

and then rode in it again this last summer out in Texas with Ray:cool:

no i havnt ridden in a S/C CSVT. i have driven/rode in many other S/C'ed vehicles. im thinking about acutally putting the bs aside and doing it in one week. i gotta order a few things but other then that i can technially put it on. i'm not worried about the tranny/motor. if they blow they blow. better reason to upgrade.
 
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