single over twin

[zSP3CTERz]

How is it ususally setup with twins? is it like 3 cylinders gets one turbo and the other 3 get the other turbo. or are some manifolds setup so all 6 cylinders go to one and then split off for the 2 turbos. So there both feeding all 6 like a single. which i would think would be pretty good.

 

[Gritz]

I would guess you save in weight reduction with single...thats a plus

 

[flight doc89]

rather than sequential, how about a compound setup? How does that compare to a big single?

 

[zSP3CTERz]

dang "flight doc89" that looks freaken mean. i cant even tell how that setup works lol :aigo:

 

[tturnpaw]

dang "flight doc89" that looks freaken mean. i cant even tell how that setup works lol :aigo:

That's completely ass backwords. I don't know who designed it but it's not going to do anything but overspool that small turbo and surge like a mofo. Now if the compressor side on the smaller turbo fed the intake on the large one that would be what I was speaking of-spooling a larger turbo at faster rates without aid.

 

[tturnpaw]

How is it ususally setup with twins? is it like 3 cylinders gets one turbo and the other 3 get the other turbo. or are some manifolds setup so all 6 cylinders go to one and then split off for the 2 turbos. So there both feeding all 6 like a single. which i would think would be pretty good.

I think you're missing the point. OK so I'll break it down. Say the stock twins flow 20lbs/min each. So together that's 40lbs/min right? Now, you buy a single with the same a/r that flows 40lbs/min. There will be no major difference in power besides that I believe the twins to cause a lot of turbulence. Thus no faster spool time because an engine is basically an air pump. The faster you get more air in and out the more power. Now a staged twin setup like I mentioned before in my previous post will be like running a dual stage nitrous setup. It will allow that larger turbo to overcome vacuum much sooner to reach positive air pressure faster with a smoother powerband than if you didn't have it. This why diesels run them more commonly (they only rev a few thousand rpms)

 

[JASONA70]

rather than sequential, how about a compound setup? How does that compare to a big single?

what the hell???? I'd like to see some numbers on this set up, and some flow tests.

 

[zSP3CTERz]

Yea your right, that little turbo looks like its getting the hell spooled out of it

 

[tturnpaw]

what the hell???? I'd like to see some numbers on this set up, and some flow tests.

Look at it again, it's a diesel. Ironically I didn't realize this till after I posted. Numbers that it would put out would not reflect a gas engine.

 

[Nalleywhacker]

dang "flight doc89" that looks freaken mean. i cant even tell how that setup works lol :aigo:

Hey keith thats the setup that silver tacoma has on it, and yes that is how a compound set up is plumed. its very nice if your wanting to run 30+ psi.

 

[honestabe]

After taking a ride in Ken Blakes MKIV yesterday that putting down 589 RWHP with methanol injection, I've decided to go single. The lag wasn't that bad. Plus the lag also allows for more streetability.

 

[zSP3CTERz]

Is the compound setup just as good as a single setup. Like could it perform just as good in high horse power plus spool fast

 

[Gritz]

After taking a ride in Ken Blakes MKIV yesterday that putting down 589 RWHP with methanol injection, I've decided to go single. The lag wasn't that bad. Plus the lag also allows for more streetability.

How long have you been scared to go single...:icon_bigg

 

[tturnpaw]

Everyone has a different view on "lag". I myself believe that on even a stock 1j at 3krpm there is no reason to have 15psi already built and ready to drop off by the time the powerband comes on at 5krpm. I say if you're really worried about boost that low you need more torque. No pun intended but that's all boost that low will give you on a 1j(port velocity=tq.) Now, if boost is fully built 500rpm before the powerband starts, I believe it's perfect not only because your powerband won't suffer but it will carry to redline and still have room to go. If you're wanting to manuver around quickly, no reason to be at 3krpm, so downshift!

 

[Nalleywhacker]

Is the compound setup just as good as a single setup. Like could it perform just as good in high horse power plus spool fast

The compound setup is the best there is, but its almost pointless on a gasoline motor, the problems with the setup is its complecated and on a gas motor your always going to be trying to keep the boost down. if your running 7psi on both turbos you'll be seeing over 30psi, which on a gas motor is alot! they can obviously be built to handle that and more but your talking alot of money! basically stay twin untill they go and then get a good streetable sized single and trust me you be plenty happy and plenty broke by then:biglaugh: oh and to answer your question its better than a single setup and it will out perform it in high horsepower and def spool fast! that tacoma see's 30psi at 3000rpms!

 

[Gritz]

Everyone has a different view on "lag". I myself believe that on even a stock 1j at 3krpm there is no reason to have 15psi already built and ready to drop off by the time the powerband comes on at 5krpm. I say if you're really worried about boost that low you need more torque. No pun intended but that's all boost that low will give you on a 1j(port velocity=tq.) Now, if boost is fully built 500rpm before the powerband starts, I believe it's perfect not only because your powerband won't suffer but it will carry to redline and still have room to go. If you're wanting to manuver around quickly, no reason to be at 3krpm, so downshift!

well said...

 

[tturnpaw]

The compound setup is the best there is, but its almost pointless on a gasoline motor, the problems with the setup is its complecated and on a gas motor your always going to be trying to keep the boost down. if your running 7psi on both turbos you'll be seeing over 30psi, which on a gas motor is alot! they can obviously be built to handle that and more but your talking alot of money! basically stay twin untill they go and then get a good streetable sized single and trust me you be plenty happy and plenty broke by then:biglaugh: oh and to answer your question its better than a single setup and it will out perform it in high horsepower and def spool fast! that tacoma see's 30psi at 3000rpms!

There's so many things I could argue with here, but instead I'll keep it simple. Wastegates are nice.

 

[Nalleywhacker]

There's so many things I could argue with here, but instead I'll keep it simple. Wastegates are nice.

No please correct me if iam wrong on something, iam just going off of the compound setup that my buddy is running on his tacoma.

 

[tturnpaw]

The compound setup is the best there is, but its almost pointless on a gasoline motor, the problems with the setup is its complecated and on a gas motor your always going to be trying to keep the boost down. if your running 7psi on both turbos you'll be seeing over 30psi, which on a gas motor is alot! they can obviously be built to handle that and more but your talking alot of money! basically stay twin untill they go and then get a good streetable sized single and trust me you be plenty happy and plenty broke by then:biglaugh: oh and to answer your question its better than a single setup and it will out perform it in high horsepower and def spool fast! that tacoma see's 30psi at 3000rpms!

Again the charge pipe between the two was backwords. It may be fine for a diesel but the major reason for having a setup like that is to aid in spoiling the larger turbo. It's not complicated if you understand how they work. There is no trying to keep the boost down when you have a wastegate. There isn't one on that setup again because diesels are different. They can be tuned to 60-80 psi easily. Gasoline is a more unstable fuel with a much lower combustion temperature and diesels run off of compression not spark. You cannot compress compressed air! In other words running 5psi from one turbo into another does not recompress the air it just forces the second turbo to spool faster. It's about volume not pressure.

 

[Nalleywhacker]

Again the charge pipe between the two was backwords. It may be fine for a diesel but the major reason for having a setup like that is to aid in spoiling the larger turbo. It's not complicated if you understand how they work. There is no trying to keep the boost down when you have a wastegate. There isn't one on that setup again because diesels are different. They can be tuned to 60-80 psi easily. Gasoline is a more unstable fuel with a much lower combustion temperature and diesels run off of compression not spark. You cannot compress compressed air! In other words running 5psi from one turbo into another does not recompress the air it just forces the second turbo to spool faster. It's about volume not pressure.

I have to totally disagree with you on this, you can recompress air to make it much denser. if not how can you run 7psi on the first turbo feed it to the second turbo which is also being wastegated to 7psi and see 30 psi at the manifold? like ive said my buddy has a tacoma with the 3rz with a compound turbo setup (two wastegates one per turbo) running a 6psi spring in both. and was seeing 30psi. ill try to get some pictures of the setup here in the next couple days.