Bypass valve and wastgates w/ Supercharger
11-11-2015, 02:57 PM
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Bypass valve and wastgates w/ Supercharger So I have read lots on here about all kinds of ways to release air from the system. I just want to make sure I have everything correct in my head.
I have been wanting to do a FMIC on my 6.0 F! procharger set up and want to pulley down and make more boost (maybe 20ish) quicker and blow it off (on the street, yes I know this is going to put more strain on the head unit plan to keep below max 70K rpm)
So from what I understand is I will need to switch out the small procharger Bypass valve that I have now with a larger one (maybe a Big Red race valve/Tial) and either vent it back into the system or the atmosphere.
Then I will have a wastegate (66MM???? bigger/smaller??)or blowoff valve (with a boost controller attached) before the IC with a spring (say 10 lbs) once it gets to 10 lbs it will blow excess off. Boost controller set up Boost to bottom to open @ low boost, add psi to top of Wastegate or BV to boost over spring?
Please let me know if this is correct and what you would do different, my goal is to have high boost when I would like it but to keep around 10-12 lbs of boost for the street.
thanks
I have been wanting to do a FMIC on my 6.0 F! procharger set up and want to pulley down and make more boost (maybe 20ish) quicker and blow it off (on the street, yes I know this is going to put more strain on the head unit plan to keep below max 70K rpm)
So from what I understand is I will need to switch out the small procharger Bypass valve that I have now with a larger one (maybe a Big Red race valve/Tial) and either vent it back into the system or the atmosphere.
Then I will have a wastegate (66MM???? bigger/smaller??)or blowoff valve (with a boost controller attached) before the IC with a spring (say 10 lbs) once it gets to 10 lbs it will blow excess off. Boost controller set up Boost to bottom to open @ low boost, add psi to top of Wastegate or BV to boost over spring?
Please let me know if this is correct and what you would do different, my goal is to have high boost when I would like it but to keep around 10-12 lbs of boost for the street.
thanks
11-11-2015, 09:51 PM
#3
Your on the right path for your goal.
I'm in the middle of my F1a with a wastegate build myself. My goals are little different than yours but the theory is the same.
This is all experimental & theoretical for me at this point as I am another month away from completion but from what I've read and heard from others is that a 44mm - 50mm wastegate will do the trick.
Yes, mounted before the IC ( closest to blower is best). I was told that the springs on the wastegate don't behave the same as they do when on the hot side of a turbo application. 10 lbs spring may hold till 15 lbs etc. ( doesn't compute to me but that's what I was told ). I'm using a boost controller to keep things accurate & controllable.
Also important to keep the un governed boost # within 5 lbs or less than the peak potential. More than that will result in too much parasitic loss as well as un necessary IATs. Ie: 20lbs peak potential, 15lbs via wastegate.
There is quite a bit if controversy surrounding this path as it's a great argument to point to the inefficiency that is created. However, if the goal is to limit peak boost/ power while taking advantage of the quick boost & lowend power then it works. In your case it seems that you just want a streetable power plant to bridge the gap between track visits.
Your goal is not uncommon & I've talked to quite a few people that do exactly what you are attempting. Limit the street power & turn it up at the track.
Key points.
50mm wastegate ( approximately)
Boost controller
Strong IC system possibly meth ( mitigate added IATs which will undoubtably occur due to ineficiency up top)
Keep potential boost & target boost within 5lbs or less of each other.
Aster bracket to limit belt slip.
Unlimited line of credit at the Tire Rack as the low end TQ will roast whatever you let touch the street.
Note: yes it will add extra strain on the head unit but not as much as 20lbs would. While it may spin @ 70k rpm it's not pushing the pressure of 20lbs ( it's at 15kbs) The rationale is that until that wastegate opens the system is operating exactly as it's designed to. Gate opens, artificial boost leak occurs and your losing efficiency from that point forward.
This an interesting article on the subject.
http://www.superchevy.com/how-to/eng...tegate-debate/
I'm in the middle of my F1a with a wastegate build myself. My goals are little different than yours but the theory is the same.
This is all experimental & theoretical for me at this point as I am another month away from completion but from what I've read and heard from others is that a 44mm - 50mm wastegate will do the trick.
Yes, mounted before the IC ( closest to blower is best). I was told that the springs on the wastegate don't behave the same as they do when on the hot side of a turbo application. 10 lbs spring may hold till 15 lbs etc. ( doesn't compute to me but that's what I was told ). I'm using a boost controller to keep things accurate & controllable.
Also important to keep the un governed boost # within 5 lbs or less than the peak potential. More than that will result in too much parasitic loss as well as un necessary IATs. Ie: 20lbs peak potential, 15lbs via wastegate.
There is quite a bit if controversy surrounding this path as it's a great argument to point to the inefficiency that is created. However, if the goal is to limit peak boost/ power while taking advantage of the quick boost & lowend power then it works. In your case it seems that you just want a streetable power plant to bridge the gap between track visits.
Your goal is not uncommon & I've talked to quite a few people that do exactly what you are attempting. Limit the street power & turn it up at the track.
Key points.
50mm wastegate ( approximately)
Boost controller
Strong IC system possibly meth ( mitigate added IATs which will undoubtably occur due to ineficiency up top)
Keep potential boost & target boost within 5lbs or less of each other.
Aster bracket to limit belt slip.
Unlimited line of credit at the Tire Rack as the low end TQ will roast whatever you let touch the street.
Note: yes it will add extra strain on the head unit but not as much as 20lbs would. While it may spin @ 70k rpm it's not pushing the pressure of 20lbs ( it's at 15kbs) The rationale is that until that wastegate opens the system is operating exactly as it's designed to. Gate opens, artificial boost leak occurs and your losing efficiency from that point forward.
This an interesting article on the subject.
http://www.superchevy.com/how-to/eng...tegate-debate/
11-12-2015, 07:15 AM
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Thanks man for your input, I do understand that the spring might not be the exact lbs but I'll have a couple and figure out which one works best. I have heard a 5 lbs spring releases at 10lbs of boost and I have heard it is less than double... guess I find out for myself haha
I have not heard this before
"Also important to keep the un governed boost # within 5 lbs or less than the peak potential. More than that will result in too much parasitic loss as well as un necessary IATs. Ie: 20lbs peak potential, 15lbs via wastegate"
I have the big procharger intercooler (4 1/2- good for 1500hp)that I picked up from someone on here for a great price and I ordered a aster bracket earlier this year in prep for this move... had to break up the cost along the way.
I have not heard this before
"Also important to keep the un governed boost # within 5 lbs or less than the peak potential. More than that will result in too much parasitic loss as well as un necessary IATs. Ie: 20lbs peak potential, 15lbs via wastegate"
I have the big procharger intercooler (4 1/2- good for 1500hp)that I picked up from someone on here for a great price and I ordered a aster bracket earlier this year in prep for this move... had to break up the cost along the way.