sequential twin turbo idea
wouldnt it be better if you wernt blocking off the downpipe but instead put one large wastegating in one of the up-pipes.
that way under the preset boost all the exhaust gasses go to one turbo, then as you hit say 10psi, the wastegate opens and feeds the other turbo.
youd probably need something like a 60mm gate
that way under the preset boost all the exhaust gasses go to one turbo, then as you hit say 10psi, the wastegate opens and feeds the other turbo.
youd probably need something like a 60mm gate
Last edited by smokinHawk; Mar 23, 2006 at 05:38 AM.
Thread Starter
single digit dreamer
iTrader: (6)
Joined: Mar 2002
Posts: 9,757
Likes: 4
From: omaha ne
Originally Posted by smokinHawk
wouldnt it be better if you wernt blocking off the downpipe but instead put one large wastegating in one of the up-pipes.
that way under the preset boost all the exhaust gasses go to one turbo, then as you hit say 10psi, the wastegate opens and feeds the other turbo.
youd probably need something like a 60mm gate
that way under the preset boost all the exhaust gasses go to one turbo, then as you hit say 10psi, the wastegate opens and feeds the other turbo.
youd probably need something like a 60mm gate
the pre turbo air would be less effected by a restriction and could get by with a single 60mm gate i bet.
TECH Addict
Joined: Aug 2004
Posts: 2,866
Likes: 4
i think its been discribed above but i will give imterpritation of it anyway! lol
why not just mount a throttle body in the hotside of one turbo???? then you can force the exhaust gases to go one way into one thtough one turbo! this would be great for street driving!
then when you wanted more boost then you could have the throttle plate WOT activavted! they take a couple of seconds to open but i bet you could get a faster one using a bigger electric motor or even a boost operated on!!
i have seen these valves used on Evos to vent the exhaust gas staright out to help spool and power! will see if i can dig it up!
and i think you should do some testing! hehehehe
thanks Chris.
why not just mount a throttle body in the hotside of one turbo???? then you can force the exhaust gases to go one way into one thtough one turbo! this would be great for street driving!
then when you wanted more boost then you could have the throttle plate WOT activavted! they take a couple of seconds to open but i bet you could get a faster one using a bigger electric motor or even a boost operated on!!
i have seen these valves used on Evos to vent the exhaust gas staright out to help spool and power! will see if i can dig it up!
and i think you should do some testing! hehehehe
thanks Chris.
Interesting idea.
The only thing I see as a concern is the obstruction to flow by placing the WG(s) in the down pipe... even a single 60mm gate would choke flow a fair amount. I like the idea of using a large electric cutout (sliding) for this, but I don't know how quick they react.
Give it a shot, I suspect it would work as planned. As stated above... it's easy to fab and convert over if it doesn't work.
Innovative thinking Dave.
The only thing I see as a concern is the obstruction to flow by placing the WG(s) in the down pipe... even a single 60mm gate would choke flow a fair amount. I like the idea of using a large electric cutout (sliding) for this, but I don't know how quick they react.
Give it a shot, I suspect it would work as planned. As stated above... it's easy to fab and convert over if it doesn't work.
Innovative thinking Dave.
Originally Posted by Wet 1
The only thing I see as a concern is the obstruction to flow by placing the WG(s) in the down pipe... even a single 60mm gate would choke flow a fair amount. I like the idea of using a large electric cutout (sliding) for this, but I don't know how quick they react.
the downpipe would have to taper to that which would restrict flow, id think youd want the downpipes 3" or bigger.
here is how a rx7 setup would look like on a V8 this would be the ideal set-up now if u noticed both intakes go to one and in a 7 there is no maf so they dont so if u go sd tuning u would run two filters (best way no one way valve and allow each turbo to have the largest cfms to suck in ) hope this helps oh i forgot in a rex the second turbo is prespooled slowly by the valve slowly opening where i have a cutout shown in the pic,also there is a another valve on the second turbos charge pipe that is open to air intill the boost reachs a set boost level and opens(which meets up with the 1st turbos charge pipe) that way the 1st turbo doesnt spin the 2nd backward.
Last edited by Moralesrx7; Mar 23, 2006 at 10:44 PM.
Originally Posted by smokinHawk
exactly why i said to put it in the up pipe instead of the down, the biggest wastegate is what a 60mm which is about 2.4" close to the normal 2.5" pipes you use for your up pipes
the downpipe would have to taper to that which would restrict flow, id think youd want the downpipes 3" or bigger.
the downpipe would have to taper to that which would restrict flow, id think youd want the downpipes 3" or bigger.
I say build the damn thing... it will work!
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Originally Posted by ddnspider
Isnt this already what they have in summit called the "super B" or something for diesels?1 turbo flows into a larger turbo after a certain value or something like that?
what about an elec exhaust cutout wired thru a boost referenced relay? it sounds like youve got it pretty much all thoughtout except for the "check valve" in the downpipe...just thought id throw this out there...
-cam
-cam
Teching In
Joined: Oct 2005
Posts: 8
Likes: 0
From: Suburb of Montreal
Originally Posted by Wet 1
I agree with you about the placement, but I still wouldn't use a WG... they disrupt the flow too much even when wide open. Ideally you'd want a blade type valve (like a TB) or a sliding valve (which doesn't have the shaft to disrupt flow), you'd want something that offers open and straight through flow. In order for the valve to be able to react fast enough, I'd think some type of boost referenced diaphragm actuator would work very well assuming you could find (or make) one which would stay closed under the pressure until you wanted it open.
I say build the damn thing... it will work!
I say build the damn thing... it will work!
TECH Addict
Joined: Aug 2004
Posts: 2,866
Likes: 4
lulu thats the sequential setup for the new 'performance' opel 2.0ltr diesel engine! looks great and a test driver said that it was seamless power all the way to the red line!!!!
this does rewquier some enginering and a lot of pipe work! but it could be done!
Chris.
this does rewquier some enginering and a lot of pipe work! but it could be done!
Chris.
Closed ex-Sponsor Account
iTrader: (1)
Joined: Jul 2004
Posts: 2,797
Likes: 0
From: Wichita Falls, TX
I could see an issue with air surging. #1 turbo duning all the work until #2 is needed. once the #2 is needed the the gates or flappers open and a huge amount of flow is going to hit both sides of the #2 Boost pressure trying to spin out to the air filter, and exhaust trying to spin out the down pipe. At that moment in time what will happen, not sure, but your boost should show a stumble or dip until #2 can catch up.
Interesting for sure.
Ricky
Interesting for sure.
Ricky
Teching In
Joined: Oct 2005
Posts: 8
Likes: 0
From: Suburb of Montreal
Originally Posted by chuntington101
lulu thats the sequential setup for the new 'performance' opel 2.0ltr diesel engine! looks great and a test driver said that it was seamless power all the way to the red line!!!!
this does rewquier some enginering and a lot of pipe work! but it could be done!
Chris.
this does rewquier some enginering and a lot of pipe work! but it could be done!
Chris.
Teching In
Joined: Oct 2005
Posts: 8
Likes: 0
From: Suburb of Montreal
Originally Posted by NXRICKY
I could see an issue with air surging. #1 turbo duning all the work until #2 is needed. once the #2 is needed the the gates or flappers open and a huge amount of flow is going to hit both sides of the #2 Boost pressure trying to spin out to the air filter, and exhaust trying to spin out the down pipe. At that moment in time what will happen, not sure, but your boost should show a stumble or dip until #2 can catch up.
Interesting for sure.
Ricky
Interesting for sure.
Ricky
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
On paper, its a nice idea, and does have massive potential.
Supras used it, as did twin turbo Subaru Legacy's. Im pretty sure both cars suffer what some Subaru guys call the "Valley of Death", which is the horrible bit in between when you switch turbos.
If mainstream car makers cant get it to work perfectly, and they would spend millions trying, it isnt going to be easy to get a good workable setup without that backing.
But if you have the time money, and skills to try it, it would be great.
Supras used it, as did twin turbo Subaru Legacy's. Im pretty sure both cars suffer what some Subaru guys call the "Valley of Death", which is the horrible bit in between when you switch turbos.
If mainstream car makers cant get it to work perfectly, and they would spend millions trying, it isnt going to be easy to get a good workable setup without that backing.
But if you have the time money, and skills to try it, it would be great.
SSU Moderator
Joined: Nov 2001
Posts: 4,857
Likes: 0
From: Austin, TX
You'd spend a 1/10th on a single with a valve or a ball bearing turbo custom made for you. But hey...if you want LOGS running into a maze of pipes, some being closed, causing sun-like surface temps and the cost of two turbos, pipe, valves, etc. go ahead.