But I decided to post anyway. I was really inspired by the guy who twin charged his sunfire a year or so ago. I love the customization and originality of it so I was thinkn, what can I do original? I put that together with the fact that I love the LOOK of a twin turbo set up on cars. So I thought, "Hey, what if I twin turbo my 2.4???"

Now before you start flamin the hell outta me please know this:
1) I am aware that twin turbo's are normally used on 6cyl or more (8,10, etc).
2) I am aware that custom intake manifoldS will be needed and custome turbo manifoldS will be needed.
3) I am aware that a good single turbo setup will probably stomp the @!#$ out of it. but again IM goin for originality
4) I am aware that I would have to build the block, internals, etc for turbo.


At the moment that is all... I prolly left something out...

Anyway, plz dont say "its all about what your lookn to spend" cuz i know that too, and I'm wiling to put money into it. I am posting b/c I want everyone's opinion on the subject. Well, everyone who has respect for originality, and realizes its not all about who finishes the 1/4mile first.
Having said that, I am actually more into muscle cars...meaning I would rather have a muscle car to have quick 1/4 mile times, but I do like the not so new anymore 4cyl thing goin on in today's society. so this is where I want something that will not only turn heads, but when i hit the track they will say "wow thats pretty respectable for a 4cyl." and when they look under the hood say "WOW...really??? thats awesome!"
I personally have never seen a 4cyl, twin turbo, much less a cavy. But I am sure it's been done, and I haven't looked either.

My only concern is that there will be one turbo adding boost to 2 cyls rather than 3 or 4. I don't see hwo it would be any different, and could easily be compensated but not running that much boost. I plan on going all out on this project unless there is a BIG issue that makes this impossible. And I'm also worried about space.

I plan on gettnig this started within the end of this year, into next year so I want to start reasearch early, b/c although im familiar with single setups, IM kinda clueless as to how a twin setup would be. IT would be too easy if it was directly like single setups, although Im hoping its only minor differences

So please hold the flames, and I ask you only to respond if you actually are interested in helping, or providnig information.


thanx
-Rob

Rob Silvera wrote:
My only concern is that there will be one turbo adding boost to 2 cyls rather than 3 or 4. -Rob

Well for starters making comments like that really says you may want to research a little more before spending money on any parts. Check out "maximum boost" by Corkey Bell for some good boost backround. Your entering a project that will eat you alive if you don't know what your doing.

purplhaze wrote:

Rob Silvera wrote:
My only concern is that there will be one turbo adding boost to 2 cyls rather than 3 or 4. -Rob

Well for starters making comments like that really says you may want to research a little more before spending money on any parts. Check out "maximum boost" by Corkey Bell for some good boost backround. Your entering a project that will eat you alive if you don't know what your doing.

Uh, what?


How would it do that ... even at all?

in terms of originality, yes i think it would be cool. for the money and time spent, it'd better be.

id like to see it. get on it man!

just make sure both turbos flow through one throttle body, lol


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

This is just an idea.... But what if ya turbo'd it with one normal setup under the hood, and then with a remote turbo setup also. I don't see how you will ever find enough room under the hood to mount two turbos. i really doubt that you're gonna end up doing a twin setup, but if you are one with some real motivation around here, i think this is your best option for originality!

and make sure both turbos are flowing equally if they are not there will be big problems!!

Tom

You could do a new style setup that are starting to be seen more on idustrial diesel motors where they have two turbos, one larger and one smaller. The larger one would take all of the exhaust into it and its tubine exhaust would enter the smaller turbos turbine and out in the the exhaust. Then the smallet turbos compressor will push into the intake of the larger turbo. This way the small turbo will spool early and you will see small boost very quickly, then the larger turbo will kick-in once you get enough exhaust going through it to spool it up for higher bost numbers.

The only thing you gotta watch out is make sure you size the smaller turbo perfectly as to not create to big of a blockage for the big turbo. Too small of a turbine housing will spool very quickly but will run out of breathe faster and hold back the larger turbo from really kick'n a$$. Same idea on the intake, big turbo sucking from small straw.

Joshua Dearman wrote:You could do a new style setup that are starting to be seen more on idustrial diesel motors where they have two turbos, one larger and one smaller. The larger one would take all of the exhaust into it and its tubine exhaust would enter the smaller turbos turbine and out in the the exhaust. Then the smallet turbos compressor will push into the intake of the larger turbo. This way the small turbo will spool early and you will see small boost very quickly, then the larger turbo will kick-in once you get enough exhaust going through it to spool it up for higher bost numbers.

The only thing you gotta watch out is make sure you size the smaller turbo perfectly as to not create to big of a blockage for the big turbo. Too small of a turbine housing will spool very quickly but will run out of breathe faster and hold back the larger turbo from really kick'n a$$. Same idea on the intake, big turbo sucking from small straw.

sounds like a sequential TT steup, didnt JDM RX-7's and Supras have those? wouldnt the turbos from them work for a cavy?


no more cavy...now 240 =]

I see a cool-air intake
It's got a NOS-fogger system and a T-4 turbo
I see an A.I.C. controller
It has direct port nitrous injection
Yeah, a stand-alone fuel management system
...Not a bad way to spend $10,000

I have no idea to be honest what the hell they call it, I'm just viewing the most recent turbo setups on the fluid pumps we use at my work. However this type of setup starts to boost at 1200RPM, where the older setup(twin offset - big and little turbo on the same manifold flowing idependantly) doesn't start to spool until around 1850rpm.

could you maybe do dual TB's me and my friend are trying to design a twin turbo system for our cars and the only thing we could think of was 1 TB for 2 cyl and just custom fab 2 intake manifolds

ahah my set up is still remembered even to this day .. would be nice to see some one come up with something different like i had done... just i personally do not know what other combo would work though...

and by the way the Twin charged set up still lives, just with a new appearance and a fair amount more power...



The First Twin Charged jbody
blue car (R.I.P) - 240whp @7psi..
silver car - 305whp 315lbs.tq @15psi (91 Octane) or 420whp & 425lbs.TQ @20psi (94 octane+Alcohol Injection)
All dynos run on a Mustang dyno

I'm using a log manifold with a single w/g, welded up the wastegates of 2 T-25 turbo's. I really dont know about engine fitment yet... but you make a normal flange near to the pulleys and about 1-1/2" offset to the trans, and the top of the manifold.
next to the firewall, it would take less space than a bigger one.. the bottom turbo o2 housing would be good but, you need a custom made one for the top turbo, or just have a shop make you a good dual downpipe.

So, you pretty much have 2 turbo's going into 1 charge pipe, 1 intercooler, and 1 exhaust. you need to spend extra money on making the dual downpipe, oil flex lines, and 2 sets of watercooling lines, extra welded t-2 flange, extra wieght. but you are also limited to the amount of boost you want to make. this setup would be good for only 9-11psi of clean boost... don't expect to go higher or the turbo's could get damaged. I don't even know if it would sound cool either.

____________________________
Dracula called, and he's coming tonight!

You don't need an extra intake manifold, just an extra flange on your exhaust manifold, and a y into your downpipe, along with a y into your charge pipes.
He's one on a 4 cylinder:
HMT FTW
and another...

Joshua Dearman wrote:The larger one would take all of the exhaust into it and its tubine exhaust would enter the smaller turbos turbine and out in the the exhaust. Then the smallet turbos compressor will push into the intake of the larger turbo.

Actually, all that should be the other way around. Exhaust goes into small turbo, then big turbo. Intake goes into big turbo, then small turbo.
This is a compound setup, sequential is different.



fortune cookie say:
better a delay than a disaster.

^Hmm...not on these setups....I'm looking at them and the exhaust goes into the larger first then the smaller one, but I was wrong about the intake, the smaller turbo intakes from the larger one.

Rob: I would at least do a twin offset turbo setup at the very least if not go for trying a compound setup. At least then you have something worth reading about and you will be first to try something that would considered a decent option to try. If you try two of the same sized turbos with two TBs(or one) and stuff all you have done is make a exspensive crappy twin turbo setup and achieve nothing of interest. At least with an offset or compound setup you can have the ability to start spool low and then flow up top with like a GT30R or something.

Edited 1 time(s). Last edited Monday, April 23, 2007 9:42 AM

It wouldn't make sense to run the larger turbine first, think about the inlet/outlet ratios...



fortune cookie say:
better a delay than a disaster.

WOW...this post took off, and No flames, im shocked. Thats cool

Anyway, I was concerned that there wouldnt be enough space. I figured I could easily move the battery to the back, take out the windsheild washer fluid tank, ac, and maybe move the Coolant tank somwhere else. Its just a tank so maybe if i got a smaller tank off a diff car and maybe moving it somewhere where else. I do however want powersteering

Um im tryin to respond to all of you in one message.
ok here's the deal

I figured I could try the sequential setup, but I'm just not a big fan of sequential, and let me see if I understand this right. U say have both turbos go thru one charge pipe and into ONE t/b. then have TWO exhaust manifolds? Doesn't that defeat the whole purpose of a twin turbo? Also say I do have both turbos going into ONE charge pipe...that would mean that I need a larger diameter charge pipe, or otherwise i just have all this backed up air.

I appologize for just jumping around, but I'm gettin excited that I actually have support and I'm so anxious to start and Ideas are just running through my head...lol

As far as the intercooler goes... do twin turbo setups have 2 intercoolers or do they both run through one? I was kinda hoping maybe i could get one intercooler and have both pipes running through it.

Here is what i was thinking....
Have the turbo manifolds run around the same way to the turbos (there is more space on the driver side than passanger side). the turbos would be sitting closer to the rear to minimize space consumption by the down pipes. Ill worry about the pipes comeing from the downpipes later.
From the turbos, i would have the pipes again running the same direction to the intercooler and to the intake manifolds. I figured I would pair up cylinders (1,2,3,4) 1 and 4 and 2 and 3. that way i could again minimize space consumption from both manifolds by haveing them "sit ontop of each other"
The only problem is i wouldnt know where to put the intakes...
This would be a whole lot easier to see if I actually had it on the car.

Naturally This car needs to be fast when its done...so to save space, smaller turbo. smaller turbo, smaller pipes, more space. It would spool faster, but I'm not sure how much power this thing would have.

I need to take this one step at a time. Since space is prolly the biggest concern at this time, if I could ask your guys' help, what turbo would be sufficient and what size diamerter pipes are we talkn here?

I think you're missing one huge aspect... If you try to run two decent size turbos off of just two cylinders, you're gonna have some serious turbo lag and still won't make any serious power even up top. And if you run two small turbos you might get some decent spool time, but still not make any serious power.

Yes you can still just run one intercooler. And yes, you will wanna Y your charge pipes together into one and only run one charge pipe up to just ONE throttle body. No reason to do things any other way.

ok...y do it with one y pipe...and how does the turbo lag work? im still not fully understanding that. Im here posting, as part of research so...

my big thing about the y pipe issue is what is the benefit/reason for doing it that way? to me that defeats the whole purpose...

Turbos do nothing but build pressure, you're gonna be pushing the same amount of pressure whether it's all in one charge pipe or in two. It'll basicly just be alot cleaner and easier to just do one.

As far as the spool time... basicly the exhaust gases/heat is what spools a turbo. The higher the flow of exhaust the faster the turbo will spool. four cylinders are gonna feed a turbo faster, and more evenly than just two.

OHV notec wrote:It wouldn't make sense to run the larger turbine first, think about the inlet/outlet ratios...

Ya, I dont know what to tell ya....but thats how this setup works...and it works really good. My thoughts is that at the lower flow than required to spool the larger turbo it flows through the larger turbine and then spools the smaller one which then the smaller turbos compressor sucks from the larger one. That way the smaller turbo when spooling creates a slight suction through the intake compressor of the larger turbo and helps the larger turbo spool up. I could see a big problem when running the smaller turbine first since the smaller housing will create a bottleneck for the flow of exhaust to the larger turbine. The larger turbines gotta be first then you can run a wastegate and the smaller turbo after the larger turbine to let all the gases out into the downpipe.

Joshua Dearman wrote:

OHV notec wrote:It wouldn't make sense to run the larger turbine first, think about the inlet/outlet ratios...

I could see a big problem when running the smaller turbine first since the smaller housing will create a bottleneck for the flow of exhaust to the larger turbine. The larger turbines gotta be first then you can run a wastegate and the smaller turbo after the larger turbine to let all the gases out into the downpipe.

But you would want that 'bottleneck' before the big one, not after it. If you place the bottleneck after the larger turbine, you create backpressure. Since the turbine mainly operates off of the pressure differential between its inlet and outlet, you would be decreasing it's energy production by increasing pressure at the outlet...
Also, placing the smaller turbine in front helps increase that initial 'suction' you referred to.
I was reading some posts by a couple guys who work on the newer turbo diesels and they said that the smaller came first, that's the only reason I'm even really questioning...



fortune cookie say:
better a delay than a disaster.

rob silvera wrote:I am posting b/c I want everyone's opinion on the subject.

originality and performance don't go hand in hand

the reason is because people do what works.
two turbos on a 4 cylinder is just a waste, especially when one turbo is more than enough to get the job done.

if you want to win shows, this will definetly give judges a boner
if you want to win races, you're wasting your time and money

so from what I'm getting, you want to run two seperate turbo systems on one engine, and basically split up 2 cylinders to have its own turbo system, and the other 2 the same thing

...<sigh>

if you do that.. remember a 4 cylinder only has one exhaust pulse per rotation

a normal 4 cylinder turbo sees an exhaust pulse every time a cylinder hits its exhaust stroke (once per revolution)

1 turbo = pulse-pulse-pulse-pulse

so its constantly being fed exhaust gas, and constantly sped up to generate the boost that you want
its also constantly feeding its compressed air into the engine since there's always one cylinder opening up for intake air.


the system that you're talkin about building would be two seperate turbo systems completely isolated from one another

keep in mind, each turbo would be pausing at points waiting for the next exhaust pulse

turbo 1= pulse - wait - pulse - wait
turbo 2= wait - pulse - wait - pulse

so both turbos would be spooling then slowing down, spooling some more, then slowing down again

not to mention you'd have to run 2 seperate intake manifolds, with two blow off valves, since as the turbo is compressing air and only one cylinder can take air in at a time. If both the #2 and #4 cylinders are closed, whats going to happen to that turbo's boost? its going to back up and damage the turbine. you'd need to run a blow off valve on both manifolds, which will bleed off the boost you're trying so hard to build, so the turbo would have to start all over everytime.

the setup you're dreaming of is a complete nightmare of overcomplexity and an engineering disaster.

I'm begging you please, don't pursue it further.. it won't work in the least bit of the sense.. and even if by some miracle it did, a rediculously small (T25) single turbo setup would make more power.

it'll be original in its execution, but it'll be the same as everything else that doesn't work

if you want to run a normal twin turbo setup with two turbos feeding into one intake manifold, that would work but its still a waste of time. unless you're looking for compound boost and 65psi or higher then its a waste.

OHV notec wrote:If you place the bottleneck after the larger turbine, you create backpressure. Since the turbine mainly operates off of the pressure differential between its inlet and outlet, you would be decreasing it's energy production by increasing pressure at the outlet...
Also, placing the smaller turbine in front helps increase that initial 'suction' you referred to.
I was reading some posts by a couple guys who work on the newer turbo diesels and they said that the smaller came first, that's the only reason I'm even really questioning...

I was referring to the compressor behind the larger turbo to generate suction through the larger turbos compressor. I dont know how a turbine would create suction.
I understand what your saying but the smaller turbo is a very small turbo and they use a (very loose?)waste-gate in parallel with the small turbo as to limit the back pressure. Being what it is I wouldn't be surprised if there isn't an electronic exhaust dump setup on there I missed to prevent the back-pressure like you were talking about. But sure as hell the larger turbine is first. I didn't do much more than look at it and notice the larger turbine then small and a WG. Theres crap loads of pipes behind the turbos which leads me to believe there might be some dumps in there too.

Like I said....on these, the larger is first....shrug.

Also, the motors I'm talking about are 3,200HP~22.0L diesels custom manufactured for Schlumberger's hydraulic fracturing pumps. On these motors they actually use 8 turbos, 4 compound sets, 4cylinders / compound setup. Theres so many ways they could route the exhaust between each setup.....but sure as night and day, the larger turbine is first on every setup. Hard to tell whats going on after that, but looks like straight into the smaller one with a WG in parallel.