centrifugal and turbo
02-08-2010, 09:23 PM
#1
On The Tree
Thread Starter
iTrader: (31)
Join Date: Mar 2008
Posts: 172
Likes: 0
Received 0 Likes
on
0 Posts
centrifugal and turbo Okay I have yet to see anyone do this. I got it ready to go together. My plan is 2.5'' check valves or anti blowback valves so as i do not push boost backwards at the turbo before it spools and wont push boost back at the supercharger when the turbo spools. My plan is 12 psi from the blower and 16 from the turbo. I have a vortech v1 s trim and am still deciding between the t76 or t88. It is going into a full cage 2000 firebird with a forged 6.0 from a 04 silverado. stock ported heads 9.5:1 compression. 126 pound per hour injectors planning on running alcohol on this setup. this piped through a 4000 stall eliminator converter and th400. the only thing left i gotta get is the rear end and turbo hot piping. I am shooting for 1000 wheel and still drive it to work. So I guess after all this ranting I am seeing what people think about the twin charge plan. If it does not work oh well I jsut figure what the hell why not try. I am trying to find the 2.5'' check valves currently. anyone have any better ideas? maybe boost sensative throttle bodies on each poweradder?
02-08-2010, 11:53 PM
#6
You could do one throttle upstream from the centri so you could yoke off its air supply when it wasn't needed anymore, and another in the normal spot to let in air from either in non-spooled operation. You might need a bypass bleed from the centri output back to the inlet to prevent overheating when its throttle was closed but the blower was still being spun.
Lastly you could look into an electric clutch for the centri, like they use on air conditioning compressors. Being able to de-clutch the centri would avoid a lot of problems and power waste (from spinning it but not getting any value or work from its output).
JIm
Lastly you could look into an electric clutch for the centri, like they use on air conditioning compressors. Being able to de-clutch the centri would avoid a lot of problems and power waste (from spinning it but not getting any value or work from its output).
JIm
02-09-2010, 06:56 AM
#7
any reason you want to use a centri and a turbo? have you considered a Positive displacement and turbo setup for real low end grunt and good top end? you would have to run a side mounted blower and configure as follows...
Air Filter to Turbo. turbo to intercooler. Intercooler you 'Y' pipe. One suide of the 'Y' through a bypass valve to the intake maniofld. on the other side of the 'Y'pipe to the intake of the SC. then SC to an intercooler/chargecooler and then to the intake manifold.
With this setup you get all the benfits of the SC down low, but one the turbo is boosting the bypass valve openand allows the turbo to do ALL the work. This prevents the restriction/inefficenies normally seen with a conventional turbo/SC compund setup. Also once the turbo is spooling the SC will just be free-wheeling as the presure will be the same on both sides.
The only probelm is where to put the Throttle bodie. It would be ideal to run 2, one in front of the SC and one on the manifold.....
Alternatively hy not run a compound/sequentical turbo setup? I have been thinking about this for a while. You could run a Truck maniolfd turbo setup with a T70 turbo at the front. This should spool REALLY quick! then 2 60mm WGs feeding into a 3inch downpipe. run the 3iunch to the rear and then stick a 88 or even 91 mm turbo at the rear. this rear turbo would also need a WG. run the pipe work back to the fornt of the car and into the intake of the smaller turbo.
Now you have a choice, Compound turbo or sequentical turboing.....
For compound set the two front WGs to say 12psi of boost and take the feed from anywhere after the front turbo and the reference to the intake of the front turbo. then set the rear to whatever presure you want MISSUS the 12psi from the front turbo. so for 20psi set the front WG to 12psi and the rear to 8psi. The rear WG will need its reference just to the atmosphear.
If you want a sequntial setup you set the fornt gates to say 12psi and the rear gate to whatever presure you want (say 20psi). reference will all be to atmosphear and feeds will both need to be from the intake manifold. with this setup the front trubo will spool, then once upto presure the gates open and the rear turbo can take up the slack.
Just some food for throught.
Cheers
Chris.
Air Filter to Turbo. turbo to intercooler. Intercooler you 'Y' pipe. One suide of the 'Y' through a bypass valve to the intake maniofld. on the other side of the 'Y'pipe to the intake of the SC. then SC to an intercooler/chargecooler and then to the intake manifold.
With this setup you get all the benfits of the SC down low, but one the turbo is boosting the bypass valve openand allows the turbo to do ALL the work. This prevents the restriction/inefficenies normally seen with a conventional turbo/SC compund setup. Also once the turbo is spooling the SC will just be free-wheeling as the presure will be the same on both sides.
The only probelm is where to put the Throttle bodie. It would be ideal to run 2, one in front of the SC and one on the manifold.....
Alternatively hy not run a compound/sequentical turbo setup? I have been thinking about this for a while. You could run a Truck maniolfd turbo setup with a T70 turbo at the front. This should spool REALLY quick! then 2 60mm WGs feeding into a 3inch downpipe. run the 3iunch to the rear and then stick a 88 or even 91 mm turbo at the rear. this rear turbo would also need a WG. run the pipe work back to the fornt of the car and into the intake of the smaller turbo.
Now you have a choice, Compound turbo or sequentical turboing.....
For compound set the two front WGs to say 12psi of boost and take the feed from anywhere after the front turbo and the reference to the intake of the front turbo. then set the rear to whatever presure you want MISSUS the 12psi from the front turbo. so for 20psi set the front WG to 12psi and the rear to 8psi. The rear WG will need its reference just to the atmosphear.
If you want a sequntial setup you set the fornt gates to say 12psi and the rear gate to whatever presure you want (say 20psi). reference will all be to atmosphear and feeds will both need to be from the intake manifold. with this setup the front trubo will spool, then once upto presure the gates open and the rear turbo can take up the slack.
Just some food for throught.
Cheers
Chris.
Trending Topics
02-09-2010, 06:58 PM
#8
On The Tree
Thread Starter
iTrader: (31)
Join Date: Mar 2008
Posts: 172
Likes: 0
Received 0 Likes
on
0 Posts
I promise I am not in over my head lol. I like the electric clutch idea though but not sure how much they will hold when a supoercharger is spinning 50k rpm and that much rotation. I imagine I would run into slippage with that set up. the plumbing idea with the y and two throttle bodies is probably the way I will go. Curious why spring check valves. I figured the swing like the old mass air flow sensors that used a potentiometer to measure air flow are pretty close to the same thing. those seemed to work for ford. I was close to twin charge on my last ss cobalt but a trailer laying across the freeway prevented that from happening. So here i am. I do not see it being done anywhere else. If it works cool if not whatever. The car was a V6 turbo before this that made 377 wheel on 12 psi so I have done more worthless things with building cars than attempting this. I like the bypass valve idea because it allows you to gradually switch from sc to by just normal spring opening characteristics. If i went with the y pipe configuration on the centri and turbo what benefit would there be putting a throttle body infornt of the supercharger? would it be operated in reverse of the other? my only problem with that setup is i can see massive iat temps.
02-10-2010, 03:30 AM
#10
I promise I am not in over my head lol. I like the electric clutch idea though but not sure how much they will hold when a supoercharger is spinning 50k rpm and that much rotation. I imagine I would run into slippage with that set up. the plumbing idea with the y and two throttle bodies is probably the way I will go. Curious why spring check valves. I figured the swing like the old mass air flow sensors that used a potentiometer to measure air flow are pretty close to the same thing. those seemed to work for ford. I was close to twin charge on my last ss cobalt but a trailer laying across the freeway prevented that from happening. So here i am. I do not see it being done anywhere else. If it works cool if not whatever. The car was a V6 turbo before this that made 377 wheel on 12 psi so I have done more worthless things with building cars than attempting this. I like the bypass valve idea because it allows you to gradually switch from sc to by just normal spring opening characteristics. If i went with the y pipe configuration on the centri and turbo what benefit would there be putting a throttle body infornt of the supercharger? would it be operated in reverse of the other? my only problem with that setup is i can see massive iat temps.
Cheers
Chris.
02-10-2010, 05:13 PM
#11
On The Tree
Thread Starter
iTrader: (31)
Join Date: Mar 2008
Posts: 172
Likes: 0
Received 0 Likes
on
0 Posts
air filter into turbo turbo pressure side into supercharger inlet, 2 bov's bypassing the supercharger (bypass valves whatever) into the throttle body, those springs set to 12 psi and the supercharger boost side into intake. i figure this way when i exceed 12 psi from the turbo it will flow past the centri and be the main power adder. If i do check valves it will be different though.
02-10-2010, 11:20 PM
#13
Don't forget that in compound boost applications boost is not a factor of addition but rather multiplication.
I understand that you are looking use a bypass to limit boost but a word of warning is that if your bypass valve(s) get stuck it could blow up a even a built motor fairly quick.
I agree with blowing a turbo into a positive displacement. Easy to do and a good power band.
I understand that you are looking use a bypass to limit boost but a word of warning is that if your bypass valve(s) get stuck it could blow up a even a built motor fairly quick.
I agree with blowing a turbo into a positive displacement. Easy to do and a good power band.
02-11-2010, 02:17 AM
#14
i can see a centi into a turbo working. Small turbo gives GOOD low end power and then the SC can at power at the top.
Another solution might be to have a small centri feed a BIG turbo. obviously the SC would then become the restriction so you would need a one ways valve BEFORE the turbo (AFTER SC) that contacted to another air filter. Then as the turbo starts to consume more air than the SC can produce then vavle open and the turbo pulls ADDITIONAL air from the other filter.....
Chris.
02-11-2010, 11:02 PM
#15
On The Tree
Thread Starter
iTrader: (31)
Join Date: Mar 2008
Posts: 172
Likes: 0
Received 0 Likes
on
0 Posts
so should the centri pressure into the turbo that way all boost is cooled or turbo feed the centri? I think either way I am going to find restrictions but I am most experienced with roots and screw blowers and heat issues. does tghe centri produce similar heat characteristics? if so I may just put the centri through the turbo. and if not I will pressure the turbo into the centri and centri into an intercooler.
02-12-2010, 12:46 AM
#17
TECH Fanatic
iTrader: (18)
Join Date: Sep 2006
Location: Nor Cal
Posts: 1,002
Likes: 0
Received 0 Likes
on
0 Posts
You are going to have a high(to me atleast) stall converter on your auto, a turbo is all you need. At the end you won't be making anymore useful power with both and it will cost you alot more.
02-12-2010, 02:34 AM
#18
9 Second Club
What a dumb idea.
You want to use a really small supercharger, that makes no boost low down, to feed a big turbo, that also makes no boost low down ?
No valves or crap are needed though. Just blow one compressor into the other. Which way round probably wont matter, as the supercharger is simply the wrong choice.
If you're going to do it, at least use a proper PD style, where it WILL improve low rpm performance.
You want to use a really small supercharger, that makes no boost low down, to feed a big turbo, that also makes no boost low down ?
No valves or crap are needed though. Just blow one compressor into the other. Which way round probably wont matter, as the supercharger is simply the wrong choice.
If you're going to do it, at least use a proper PD style, where it WILL improve low rpm performance.
02-12-2010, 06:39 PM
#19
I'm with stevie on this. It's a bad idea, too complicated, lots of parts needed to work right, won't make any more power than a well-matched single turbo, plus some basic laws of thermodynamics are being ignored.
As long as you are spinning the centri, you aren't getting the "turbo advantage". Might as well just run a centri alone. Even with the discharge routed to atmosphere, it will be sapping up 50++ hp.
As long as you are spinning the centri, you aren't getting the "turbo advantage". Might as well just run a centri alone. Even with the discharge routed to atmosphere, it will be sapping up 50++ hp.
