My twin turbo experiment = 46psi

[MissDrew]

Thanks

[Ley269]

Ahhh, now I see, it's all clear now. I had thought the compressor from the small turbo was going to the exhaust turbine of the larger turbo, but now I can see how you can get the adding of boost. As the second stage (small) turbo is getting it's air from the outlet of the large turbo, you will have to be careful it doesn't cause the small one to 'stall'. Good luck with the project. If I could figure out how to adjust the fuel on my 13-BT....

[Dzltec]

Ley, i happy thats all clear, I may have to fit an external wastegate to stop the ct26 from overdoing itself. What do you mean by stall??

I havent heard of that before.

If your 13bt is all factory turbo, fuel adjustment isnt that hard.

cheers

[dow50r]

Put a pusher pump in the fuel system....and see if it makes the extra kw's...

[dow50r]

The exhaust may have to much room to get out the exhaust manifold with 2 turbines in parallel....nice experiment

from that dyno sheet it appers that either or both (a) the big turbo is too big for the motor (b) the motor runs out of fuel at 125kW.

big boost without intercooling is not necessarily a problem in itself, and the fact that the EGT's are low suggest that the turbos are not adding a lot of heat to the inlet air so I wouldn't be too worried on that score - in fact it is probably the sheer size of the big turbo, hardly working, that means (a) low EGT's (b) boost building all the way to redline instead of building rapidly and plateauing.

do you have any specifications on the big turbo? A/R ratios and port diamters for starters?

[Snatchy]

Great to see someoone having a go at a Twin set up. The cummins 5.9 seems to be a common TT canditate in Nth America with ~50psi. About time someone tried the same treatment on the Jap diesels over here.... so nice one Dzltec.
I look forward to seeing how things progress.

[ats4x4dotcom]

My thoughts with the way the ineffecient inlet is set up on the 1h series was to split the inlet plenum with 2 intakes, and run 2 turbos, split from the exhaust, allowing smaller units to come on sooner, but make more boost combined than the one original.

[Rb25sil80]

..

[Dzltec]

Ats,

that thought had crossed my mind, toyota do it with he soarer.

However you have a smaller turbo being driven by 3 cylinders instead of 6, so it sort of counterbalances itself to some degree. They then dont produce the flow or ppressure that a compound system will.


Snatchy,

thats where I got the idea from. They go insane for their dodges. I have seen a dyno graph that does 1000+ hp at the tyres on a 5.9 dodge.


Am playing again in the near future, would love to crack 200rwkw, but we will have to see.

[dow50r]

Couple of things...if you boost up, you need to intercool or you loose efficiency from charge heat...remember the exhaust side is feeling thesame sort of boost pressure the inlet makes...also remember turbos work by differential pressure, so if the ct26 is restricting the larger ones exhaust side, you are loosing there at higher speeds...and this bumps up EGT and the hdt hasnt the best combustion chamber for discipating heat between the valves, so we have gone round and are back to intercooling..
So my suggestions are to cool the incoming air first. Then look at timing of std pump...to minimise backing off due to loss of internal pump pressure, due to volume injected....install that pusher pump to circulate the fuel
I see this system would allow less lag to one large turbo, but the smaller is restricting the high rpm flow exhaust wise aswell as compresser wise.
Maybe that larger turbo up where the ct26 is plus another bigger one underneath would result in std lag and huge power up high.
Lastly, get that filter sucking cold air out of the engine bay.
Andrew

[pioneer411]

great work dunno what u mind email me pics of turbo side of ur engine??? as i modify 12H-turbo now, its hard to modify the fuel pump, thats why thinking to modify 1HDT now on .. i also got fren runnning single turbo 1hdt with 15sec 0-400

[simkell]

is the flow of air from the larger turbo getting restricted by the smaller turbo.
If the large turbo is producing up to 30psi, would it beneficial to run a bypass system. this would eliminate the restriction of air going though the smaller turbo. i would also start thinking about intercooling as soon as you add more fuel your egt's will rise as stated earlier.

whats your goal from this?
is it to produce max power until the engine blows?
anyway good to see someone is trying something different.

[dow50r]

Maybe a supercharger till the large turbo spools up...then disconnect drive...as in toyota 1ggze charger controlled by a hobbs switch...that would make power from idle and no restriction on the exhaust side...
Andy...is the motor still alive?? ct26's like to shed impeller vanes at 14 or so psi...you are ending up with 26 psi from the gt turbo

[Dzltec]

Yes the engine and turbo are still alive, the system has now been transferred to my shorty patrol. 80 series is now back to standard setup as wifey wanted her car back.

The system worked very well even without intercooling, but i/c is the way to go. The patrol was making 180ish non i/c. We did some further mods, changed injectors went for a drive and the engine lunched itself. Guess I found a na td42 limits. Boost was a fairly flat 50-55psi.

Engine will now be toughened up to suit. The standard ct26 is still going strong.

Andy

[Tapage]

You are my hero dude ..

I thought with this amount of boost = air you can run 4" exhaust ..

And 46 PSI you will pushing hard rings, con rods and many stuff inside the engine ..

Did you make a comp test before and after your compound setup ..?

P.S. and I;m happy with 14 PSI

[Newhouse]

Hows the shorty patrol project coming along?? Would love to see some pictures.

[bj on roids]

Ats,

that thought had crossed my mind, toyota do it with he soarer.

Parallel turbos on the soarer

sequential on the supra

[bj on roids]

there is no pics on the whole thread :(

[Dzltec]

Happy to see this thread brought up again. There were pics at the start, but the outerlimits stopped hosting pics so they went.

I can do pics from my shorty, but you dont get to see much, its pretty tight.


Andy

[Newhouse]

Hey Andy,

Pics would be cool, and any dino results, thoughts on how the shorty goes would be awesome. Did you get my PM?

Cheers,

Chris.

[LuxyBoy]

What do you mean by stall??

The surge region, located on the left-hand side of the compressor map (known as the surge line), is an area of flow instability typically caused by compressor inducer stall. The turbo should be sized so that the engine does not operate in the surge range. When turbochargers operate in surge for long periods of time, bearing failures may occur. When referencing a compressor map, the surge line is the line bordering the islands on their far left side.
Compressor surge is when the air pressure after the compressor is actually higher than what the compressor itself can physically maintain. This condition causes the airflow in the compressor wheel to back up, build pressure, and sometimes stall. In cases of extreme surge, the thrust bearings of the turbo can be destroyed, and will sometimes even lead to mechanical failure of the compressor wheel itself.

Common conditions that result in compressor surge on turbocharger gasoline engines are:

A compressor bypass valve is not integrated into the intake plumbing between the compressor outlet and throttle body

The outlet plumbing for the bypass valve is too small or restrictive

The turbo is too big for the application

[LuxyBoy]

Maybe a supercharger till the large turbo spools up...then disconnect drive...as in toyota 1ggze charger controlled by a hobbs switch...that would make power from idle and no restriction on the exhaust side...

Wouldn't this cause a big shock loading on the motor as you rev up each gear
You have one system shutting down and one kicking in; I would have thought you would need to match this changeover to be at the exact time and for the turbo to start on the exact power that the S/Charger system had reached.
If not matched it would be a very jerky ride too.

Very interested to hear your responses

[dow50r]

Brad, your most probably right, the fact none i know of are getting around probably means its too hard to control. If it werent, we would all have power from idle to redline.
Ive found it hard to get the mind around flow and the result of flow...pressure. The facts are, Andys hdt improved its power figures and more importantly, it hauled ass...food for thought for those of us who like to play

[turbogu]

Detroit diesels run superchargers and turbo chargers at the same time on some of there 2 stroke diesel engines so it can be done, have seen guys with detroits making boost just idling!!!!! Some guys in the states are now doing that on there 5.9 cummins motors to

[LuxyBoy]

Detroit diesels run superchargers and turbo chargers at the same time on some of there 2 stroke diesel engines so it can be done, have seen guys with detroits making boost just idling!!!!! Some guys in the states are now doing that on there 5.9 cummins motors to

I would assume that they would have to run a positive displacement super charger (as opposed to a centrifugal) then the turbo; be silly not to intercool that setup too.

It would be very interesting to see the flowing rates:
After the charger
After the turbo
Final engine input rate after intercooler and all the plumbing.

Also how long they last:
Charger from back pressure
Turbo from front and back pressure
Engine from taking it all

No point having a fun toy if you can't afford to run it, as it breaks every 100,000km

[dumbdunce]

Detroit diesels run superchargers and turbo chargers at the same time on some of there 2 stroke diesel engines so it can be done, have seen guys with detroits making boost just idling!!!!! Some guys in the states are now doing that on there 5.9 cummins motors to

I would assume that they would have to run a positive displacement super charger (as opposed to a centrifugal) then the turbo; be silly not to intercool that setup too.

It would be very interesting to see the flowing rates:
After the charger
After the turbo
Final engine input rate after intercooler and all the plumbing.

Also how long they last:
Charger from back pressure
Turbo from front and back pressure
Engine from taking it all

No point having a fun toy if you can't afford to run it, as it breaks every 100,000km

all two stroke diesels have a scavenge blower, which is positive displacement, but not necessarily a supercharger. a two stroke needs the air to be forced into the cylinders or it just won't run. It is possible and frequently happens that the blower is overdriven to produce a mild boost. The turbo, if present, sits upstream of the blower, and they are quite often run without an intercooler.

[tuffsahara]

so is this turbo setup a sequential type setup? if so theres a guy over here in perth whos done two sequential setups with great results i work with him theres a few secrets to getting it to work hes done two successfully so far one on a jza80 supra with a 2jz and another on his own car an mr2 which he's done a 1mz v6 conversion to it and then put sequential turbos on it with amazing results pm me if you want his website address email etc... wont post it on here so its not advertising

[Chucky]

Detroit diesels run superchargers and turbo chargers at the same time on some of there 2 stroke diesel engines so it can be done, have seen guys with detroits making boost just idling!!!!! Some guys in the states are now doing that on there 5.9 cummins motors to

I would assume that they would have to run a positive displacement super charger (as opposed to a centrifugal) then the turbo; be silly not to intercool that setup too.

It would be very interesting to see the flowing rates:
After the charger
After the turbo
Final engine input rate after intercooler and all the plumbing.

Also how long they last:
Charger from back pressure
Turbo from front and back pressure
Engine from taking it all

No point having a fun toy if you can't afford to run it, as it breaks every 100,000km

all two stroke diesels have a scavenge blower, which is positive displacement, but not necessarily a supercharger. a two stroke needs the air to be forced into the cylinders or it just won't run. It is possible and frequently happens that the blower is overdriven to produce a mild boost. The turbo, if present, sits upstream of the blower, and they are quite often run without an intercooler.

You will also find that many of these 2 stroke diesels are classed as N/A as the exhaust valves are still open after the piston closes the intake ports in the cylinder. As DD said, these diesel won't even start without the blower attached.

[Z()LTAN]

thats how 2 stoke works... you need the blower to enable the scavenging stoke...

[ledgend80]

dzltec some pics of the setup on the shorty would be great even better some of when it was on the cruiser would be even better. also a little off topic but what have you found to be a good replacement turbo for the ct26 on 1hdt enginge any help much appreciated