Will this work?
Im planning on buying a ka24de over the summer and rebuilding it. I was hoping to strap on a big turbo, and then another small one that would spool up faster. And what all would i have to get to rebuild the ka-de? Im a noob when it comes to rebuilding, i couldnt tell u the difference between a header and a rod. if anyone could tell me if my dual turbo idea would work and what all i would prolly need to get to rebuild my engine and set up my dual turbo i would appriciate that, thanks in advance.
Planning on gettin ka-tt
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C-Kwik
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This has been discussed before. Chances are it will be very complicated for the results you are probably thinking of. The simplest twin set up would be to run the turbos in parallel. But using two different sized turbos will make chossing the right turbo and predicting the response a lot more complicated and perhaps erratic. But this will also negate what I am guessing you want out of this. Fast spool up with high efficiency at almost all RPMs. Running two different turbos in parallel will divide the airflow of the exhaust gases proprtionately to what each turbo needs to produce the intended boost. A pure twin(same size turbos) parallel system will divide the airflow in half and both turbos will be doing the same amount of work. In both cases, the turbos will spool up slower than a single turbo from either set-up will by itself. To achieve the quick response with high efficiency at high flow rates, you need a sequential system of some sort.
A few cars have this. The MKIV Supra and the RX-7 are two examples. But both use two same size turbos. Only one is active all the time. But at a certain RPM and load, closed throttle plates in the intake and exhaust open up to allow flow through the second turbo. It basically turns it into a twin parallel set-up.
Running two different sized turbos may be optimal for the results you want, but becomes even more complicated. Coupling a smaller turbo with a larger one is likely going to bring down the overall efficiency and flow to less than that of a well matched single turbo. So what will likely have to happen is the first turbo would be active during low RPM and/or low loads. But at high RPM's and high loads you'll want the larger turbo to take on the load. This means you will need to block off airflow to the smaller turbo. Sequntial twin turbos are complicated enough, both in hardware and tuning. And it only has to open throttles. To make the most of two different sized turbos you'ld have to add more hardware to block off the smaller turbo and tune it to run properly or even optimally. It's an easy enough idea to conceive. But can be very complicated to actually try. Chances are a well chosen turbo will provide much better results.
And if you do decide to try any kind of a sequential set-up, study and perhaps even take apart a sequential system from a Supra or RX-7. If it doesn't discourage you, it will at least give you some idea of how to accomplish this feat. I've removed the turbo systems off of 2 Supras. One of them we put back on, but used a modified turbo in one. The other we ditched in favor of a larger single turbo. The one with two different sized turbos naturally did make more power, but it did not have a seamless transistion between the first turbo and the spool-up of the second turbo. It provided quite a kick when the second one came online. The system with the single turbo made a ton more power at much less boost and while it wasn't responsive, it was not a big deal. It was much smoother and controllable.
And since you self proclaim yourself a noob, I highly recommend you learn in pretty good detail how a turbo works and what the differences in turbos really are. This isn't something as simple as bolting on a prefabbed kit. Perhaps start with a good book. And if you do not know motors, I'd start at the basics.
A few cars have this. The MKIV Supra and the RX-7 are two examples. But both use two same size turbos. Only one is active all the time. But at a certain RPM and load, closed throttle plates in the intake and exhaust open up to allow flow through the second turbo. It basically turns it into a twin parallel set-up.
Running two different sized turbos may be optimal for the results you want, but becomes even more complicated. Coupling a smaller turbo with a larger one is likely going to bring down the overall efficiency and flow to less than that of a well matched single turbo. So what will likely have to happen is the first turbo would be active during low RPM and/or low loads. But at high RPM's and high loads you'll want the larger turbo to take on the load. This means you will need to block off airflow to the smaller turbo. Sequntial twin turbos are complicated enough, both in hardware and tuning. And it only has to open throttles. To make the most of two different sized turbos you'ld have to add more hardware to block off the smaller turbo and tune it to run properly or even optimally. It's an easy enough idea to conceive. But can be very complicated to actually try. Chances are a well chosen turbo will provide much better results.
And if you do decide to try any kind of a sequential set-up, study and perhaps even take apart a sequential system from a Supra or RX-7. If it doesn't discourage you, it will at least give you some idea of how to accomplish this feat. I've removed the turbo systems off of 2 Supras. One of them we put back on, but used a modified turbo in one. The other we ditched in favor of a larger single turbo. The one with two different sized turbos naturally did make more power, but it did not have a seamless transistion between the first turbo and the spool-up of the second turbo. It provided quite a kick when the second one came online. The system with the single turbo made a ton more power at much less boost and while it wasn't responsive, it was not a big deal. It was much smoother and controllable.
And since you self proclaim yourself a noob, I highly recommend you learn in pretty good detail how a turbo works and what the differences in turbos really are. This isn't something as simple as bolting on a prefabbed kit. Perhaps start with a good book. And if you do not know motors, I'd start at the basics.
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HolyShiznit
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- Car: Working on my car
In my case, I wanted to have fun and be different. And I like spending time on my car. just bolting up a T3/T4 and calling it day wasn't nearly enough time, blood, or money wasted for me.
Anyway if I were you, first I would read corky bell's maximum boost. Then I would go read the thread in the forced induction forum about sequential turbos.
I still think that for a sequential setup the way to go would be a small T25 and a T04b with a very large wastegate setup to open the exhaust gases to the larger turbo at a set boost/rpm level.
Another way to do it would be to run everything through the large turbo, and then run two pipes off the turbine outlet, one through the small turbo and another through a large wastegate and through a pipe, then Y them back together.set that wastegate to open at a certain rpm (once the small turbo reached full spool).in this way the gases would pass through the large turbo then spool the small one. once the small one reached max boost (presumably the large one would already be spooled at that point) the wastegate would open, bypassing the smaller turbo and opening up the second exhaust pipe so as not to create a restriction.
Dunno, there are more than one ways to do it. It would be interesting to see how it worked out.
Anyway if I were you, first I would read corky bell's maximum boost. Then I would go read the thread in the forced induction forum about sequential turbos.
I still think that for a sequential setup the way to go would be a small T25 and a T04b with a very large wastegate setup to open the exhaust gases to the larger turbo at a set boost/rpm level.
Another way to do it would be to run everything through the large turbo, and then run two pipes off the turbine outlet, one through the small turbo and another through a large wastegate and through a pipe, then Y them back together.set that wastegate to open at a certain rpm (once the small turbo reached full spool).in this way the gases would pass through the large turbo then spool the small one. once the small one reached max boost (presumably the large one would already be spooled at that point) the wastegate would open, bypassing the smaller turbo and opening up the second exhaust pipe so as not to create a restriction.
Dunno, there are more than one ways to do it. It would be interesting to see how it worked out.
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240marcuSX
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- Car: E34 525i
E46 M3
no woman I have ever met would be able to discern the difference between a sequential and parallel twin turbo system. Most of the women I have ever met couldn't tell the difference between twin turbos and a single turbo. A lot of the women I've met couldn't tell if an engine was turbocharged at all.Of the above, the majority don't care either way.Of the ones that remain, very few would be attractive enough to matter.
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240marcuSX
- Posts: 4005
- Joined: Sat Feb 22, 2003 11:00 am
- Car: E34 525i
E46 M3
if you read carefully I left it open. There are a handful scattered around. just not many. Anyway back to the TT thing, don't let people talk you out of it. Once you read up you may realize just how much work it is... and realize you will be doing it all yourself cause there isn't this cookie cutter **** "oh, well do this." I realized those things, went ahead, and trust me its easy to get in real far before you know it. but if you really wanna try it I would encourage you. The ka24de is an excellent choice. the 240 is RWD, and it has plenty of room in the engine compartment to house the turbos and stuff.