Twin turbo? [Merged 11-6]

[Thxbrett]

Actually most of the sequential twin turbo systems run the same size turbos, not smaller and bigger ones. As far as I know the only sequential system that has two different sized turbos on the motor is the Mazda Cosmo 3 rotor 20B in Japan. Both the RX-7 and Supra have the same size turbos front and back. The only other production vehicles that I am aware of that had sequential twin turbos was the Porsche 959 and the Subaru Liberty B4.
The Subaru has a sequential twin turbo 2.0 liter 4 cylinder but makes it work because of it's flat 4 design. I don't beleive an inline 4 is a good platform to twin turbo. Better off going with a larger single. Here is a link of the Subaru B4:

http://www.autospeed.com/A_1229/P_1/article.html

Brett.

 

[Tranman]

Originally posted by OC TEAM ECLIPSE
never heard of 4 cylinder twin turbo....

Actually there are some, I remember seeing a twin turbo kit on a stroked SR20DET in a Silvia..I think it was displacing 2.4L. AND it was running HKS BB turbos, but I'm not sure how much power he was running. Of course the advantage of a SR engine in RWD format is the extra room for the turbos. There isn't much room in a FWD type of format.

 

[pneumo]

OK just for giggles, what if you do a twin T25 setup with exhaust from three cylinders going to one turbo for fast spoolup, and one cylinder powering the second turbo. Then add a wastegate on one of the 3 cylinder side going into the single cylinder turbo. So when this wastegate opens you get 2 cylinders flowing into each turbo. Then of course you need a regular wastegate to limit full boost. But the first wastegate can be set to open at maybe half boost so that both turbos are working to raise boost the rest of the way up. Know what I mean? It's just a thought. I have no intention of trying this, it's just a cool idea.

 

[GVR4#1353]

Originally posted by mclaren55
No, and have fun trying to run all that IC piping, exhaust piping, etc etc etc. Those combined probably flow less then a bloody 20g, it wouldn't be worth the time. Personally, I think it is a stupid idea to begin with.

ding ding ding, we have a winner....thank you for saying what I would have said.....btw.....a T25 is WAYYYYYY too small for a Camaro even on a TT setup......both ideas are really stupid

 

[Seamus]

Originally posted by Thxbrett
Actually most of the sequential twin turbo systems run the same size turbos, not smaller and bigger ones. As far as I know the only sequential system that has two different sized turbos on the motor is the Mazda Cosmo 3 rotor 20B in Japan. Both the RX-7 and Supra have the same size turbos front and back. The only other production vehicles that I am aware of that had sequential twin turbos was the Porsche 959 and the Subaru Liberty B4.
The Subaru has a sequential twin turbo 2.0 liter 4 cylinder but makes it work because of it's flat 4 design. I don't beleive an inline 4 is a good platform to twin turbo. Better off going with a larger single. Here is a link of the Subaru B4:

http://www.autospeed.com/A_1229/P_1/article.html

Brett.

the rx7s turbos have different compressor wheels. i beleive 54 andf 58 mm. So know, they are not identical.

 

[GRNDSM]

Originally posted by GVR4#1353


btw.....a T25 is WAYYYYYY too small for a Camaro even on a TT setup......both ideas are really stupid

I am not so sure about it... It might be too small to run above 14psi on a very efficient 4G63 above 6k rpms, but when you are talking about 2.8L of 2 valve per cylinder technology, all under 5500-6000 rpms and under 10psi of boost, it just might work pretty well.

Leon
RR

 

[LaserRST]

I found some one selling a twin set up for our cars on EBAY!!! If I can find the link I will try to post it!!!

 

[LaserRST]

Go to the search and type "Is THIS a sequential turbo setup?".... It has a pic of a twin turbo set up that sold for over 1,000.00 on EBAY. Looks pretty sweet and the seller claimed it can produce over 500 HP. Have fun dreamin.... pave the way for the skeptic, and never listen to any one tell you you cant do it.

 

[Thxbrett]

The RX-7 has two identical Hitachi turbos of 51mm each. I worked for a RX-7 shop for two years and owned one of these fine time bombs. The newer 99 turbos are actually a little smaller at 50mm each but have an abraidable seal and spool a little quicker. Both sets of turbos are identical in size as are the CT series turbos on the Supra.

Brett.

 

[Seamus]

you are right, i ran out to the garage(my 7 is in peices) and the wheels on both are 51mm i was always under the impresion that secondary was a little larger. turbine sides are 57 htough i am pretty sure.(their still joined can't measure)

 

[GVR4#1353]

Originally posted by GRNDSM


I am not so sure about it... It might be too small to run above 14psi on a very efficient 4G63 above 6k rpms, but when you are talking about 2.8L of 2 valve per cylinder technology, all under 5500-6000 rpms and under 10psi of boost, it just might work pretty well.

Leon
RR

I am sure about it.....name one turbo kit for a Camaro that uses a T25....just one.......there isnt any. Every TT setup for a Camaro uses a T3 or larger....usually the T3 setups cant make over 500hp either, the turbo's max out too quickly and just dont flow enough for the motor, the usual setup for a V8 Camaro is twin T3/T4's

edit: btw....when you say 2 valves per cylinder you also have to remember that even though there are only 2 valves per cylinder they are much much larger than a valve from a 4 cylinder motor

also the difference between a 2.0L and 2.8L is a big azz difference when you're talking flow rates (since you're talking 2.85L per turbo) look at the 280ZXT, that is a 2.8L motor and those run T3's, the T25 would be way inefficient on that motor, just like its a joke to even think about putting those dinky things on a Camaro

 

[GRNDSM]

>I am sure about it.....name one turbo kit for a Camaro that uses a
>T25.... just one.......there isnt any.

I can’t imagine any V8 guy doing such kit… DSMers toss this idea a lot because we have a rather large supply of cheap T-25 turbos around, but that would not be a natural turbo of choice for anyone outside of DSM world.

>Every TT setup for a Camaro uses a T3 or larger....usually the T3
>setups cant make over 500hp either,

I see you point, and I should have mentioned the hp level. Naturally, you could not make 600+hp from two T-25’s. But ~400hp should be possible. Another problem with this argument, is that most V8 guys would rather make 400hp with out the turbos .

>btw....when you say 2 valves per cylinder you also have to remember
>that even though there are only 2 valves per cylinder they are much
>much larger than a valve from a 4 cylinder motor

Right, but their volumetric efficiency is still much worse than on a 4 valve motor. That means that means that it will be much easier to maintain the same level of boost. But who is talking about the same level of boost? I was talking about building around 8psi of boost. Which T25 should not have much trouble with. 8psi on 2 valve motor is something like maintaining 5psi on 4 valve motor (~5psi is made up to illustrate the point, but it should be less than 8psi).

>the difference between a 2.0L and 2.8L is a big azz difference when
>you're talking flow rates (since you're talking 2.85L per turbo)

And what about RPMs? Do RPMs make any azz difference to offset the displacement?


>look at the 280ZXT, that is a 2.8L motor and those run T3's, the T25
>would be way inefficient on that motor,

I have no idea what turbos come on those cars but just because it is a “T3” does not mean that it flow much more than a T25…

>just like its a joke to even think about putting those dinky things on a Camaro

All depends on what power you are looking to get…

I was considering using two T25s on my Durango. I think that they would make a perfect turbos for small boost system. Like increasing the power from ~230hp to ~ 350hp. It would not transform it into an 11 sec monster, but it should give it a healthy boost in power.

Leon
RR

 

[abrxy3]

about the supras goin from TT to single. true that allows supras to reach high hp ratings and most street supras will feature this setup, but when you wanna reach hp in the 1100 + range twins are the only way to go, a single just wont support that without goin hella high psi. look at the twin GT2835 and GT3037 kits for the supra, that allows them to reach 1200 hp + with lower boost levels. single is ideal within streetable ranges, but twins are the key to insane hp, at least in the supras case.
btw there are 6 cyls taht dont come with single kits only dual, ie the vr4

 

[GVR4#1353]

Originally posted by GRNDSM
I can’t imagine any V8 guy doing such kit… DSMers toss this idea a lot because we have a rather large supply of cheap T-25 turbos around, but that would not be a natural turbo of choice for anyone outside of DSM world.

thats because its pointless to use that small of a turbo and spend the money on the manifolds and turbo parts to make 500hp when $600 for nitrous will make more power....the only way its worth it is to go with a turbo that will actually do something for the motor

I see you point, and I should have mentioned the hp level. Naturally, you could not make 600+hp from two T-25’s. But ~400hp should be possible. Another problem with this argument, is that most V8 guys would rather make 400hp with out the turbos .

correct, as I said above, why bother

Right, but their volumetric efficiency is still much worse than on a 4 valve motor. That means that means that it will be much easier to maintain the same level of boost. But who is talking about the same level of boost? I was talking about building around 8psi of boost. Which T25 should not have much trouble with. 8psi on 2 valve motor is something like maintaining 5psi on 4 valve motor (~5psi is made up to illustrate the point, but it should be less than 8psi).

you are right about the volumetric efficiency, however if you have $5k lying around and are concerned about that they do make 4 valve per cylinder heads for small block chevys (that conversion alone on a LT1 motor takes you from 300-420hp with no further mods).....and on the boost issue, again, why bother spending all that money on the turbo setup when nitrous is cheap and very effective....not to mention you can go buy a ATI Procharger to run at 8psi and crank out around 450RWHP (LT1/LS1) right out of the box without having to do any custom fabrication to fit any turbos

And what about RPMs? Do RPMs make any azz difference to offset the displacement?

yeah, it does play into the equation but you are very misinformed if you think a pushrod V8 cant rev like a 4 cylinder....take a 400ci Pontiac motor with a 350ci Chevy crank and you have a 377ci pushrod motor that can rev to 9k rpms....or just use some chromoly pushrods with some comp cam dual valve springs and some roller rockers and you can get 7k-8k rpms out of a stock 350

I have no idea what turbos come on those cars but just because it is a “T3” does not mean that it flow much more than a T25…

its a Garrett T3, and from my understanding those flow a lot more than the T25 on the DSMs

All depends on what power you are looking to get…

I was considering using two T25s on my Durango. I think that they would make a perfect turbos for small boost system. Like increasing the power from ~230hp to ~ 350hp. It would not transform it into an 11 sec monster, but it should give it a healthy boost in power.

I just dont see the point in using such small turbos on such a big motor when there are plenty of less expensive options that have much more potential....unless you just have money burning a hole in your pocket

 

[GRNDSM]

>take a 400ci Pontiac motor with a 350ci Chevy crank and you have a 377ci
> pushrod motor that can rev to 9k rpms....or just use some chromoly pushrods
>with some comp cam dual valve springs and some roller rockers and you
>can get 7k-8k rpms out of a stock 350

That might be the case on specialty build V8s, a typical V8 would be limited to 5500-6000rpms…

>its a Garrett T3, and from my understanding those flow a lot more than the T25 on the DSMs

There are literally dozens of “T3” turbo combinations! Depending on which one you are talking about, it can be smaller than a T25. To say that they used a “T3” turbo is like to say that they used a “6 cylinder engine” and not mention the size…

BTW Did you ever the see size of the wastegate hole on a popular 5 bolt T3 housing that is used in many DSMs? It is around 5/8”, I hate to imagine just how small of a turbo it must have been meant for by Garrett.


>I just dont see the point in using such small turbos on such a big motor

Even if all I want is 350hp?

>when there are plenty of less expensive options that have much more potential...
>unless you just have money burning a hole in your pocket

Lets see:

Popular Supercharger kits for Magnum motor (6-7 PSI) $2800-$3800 w/out intercooling. Improvement ~ 100hp.

T-25 turbos (~$100 each), I can do all the other stuff for under a grand, so we are still talking about at least ½ the price of “off the shelf” supercharger kit….


So turbo kit can be a lot less money. Unless you know of a place where I can get a Powerdyne SC for under $2k, please let me know and I will buy it instead .

Leon
RR

 

[GVR4#1353]

Originally posted by GRNDSM
That might be the case on specialty build V8s, a typical V8 would be limited to 5500-6000rpms…

ok, if you wanna be like that then LS6 or LT5, LS6 will go to 7k and LT5 can go to 8k with minor mods (those are factory motors)
my LT1 can go to 6500 on stock valvetrain

There are literally dozens of “T3” turbo combinations! Depending on which one you are talking about, it can be smaller than a T25. To say that they used a “T3” turbo is like to say that they used a “6 cylinder engine” and not mention the size…

this is true and I dont have the exact specs so I'll let this one slide, however, if you look at the compressor wheel on the T3 from a 280zxT compared to a T25 from a DSM you'll see what Im talking about

Even if all I want is 350hp?

YES!!!!!.....the Camaro is what we're talking about here and if all he wanted was 350hp out of it (its 300hp stock) then all he needs is some long tube headers, exhuast and a K&N filter......exhuast alone on a 350ci motor will at 20rwhp and I've seen some good long tubes add 30rwhp

Lets see:

Popular Supercharger kits for Magnum motor (6-7 PSI) $2800-$3800 w/out intercooling. Improvement ~ 100hp.

T-25 turbos (~$100 each), I can do all the other stuff for under a grand, so we are still talking about at least ½ the price of “off the shelf” supercharger kit….


So turbo kit can be a lot less money. Unless you know of a place where I can get a Powerdyne SC for under $2k, please let me know and I will buy it instead .

last time I checked Chevy was still using Chevy motors in their Camaros which is what we're talking about here....forget the Mopar crap, and for your information you can always buy used superchargers for 1/2 the price.....dont think he was buying brand new T25s for the setup and a turbo manifold for a Camaro will cost around $400-$600 per side for fabrication, the piping will probably run you around $200, then you have the intercooler $400-$1000 (depending on how you want to do it......then there's always that pesky room issue......go down to a Chevy dealership and look under the hood of the Camaro then come back and tell me where you're going to mount those turbos, there are kits for them but I believe the kits place the turbos under the car where they can scrape......hence all the Camaros running nitrous or a supercharger instead of turbos

another thing.....the ATI Prochargers come with intercoolers, and if you want a Powerdyne (dont see why) Summit has them for $2400

 

[23LBS]

I checked out the extreme mortorsports web page and got the list of parts and stages to build my car for the track so far everything is going according to plan im was ready to go and get the 20g turbo but im contemplating if it is possible to go twin or sequintial turbo?

would i be better off getting a bigger turbo or would a twin turbo even work on my 1g??


if anyone knows can you let me know... im trying for march 15th weekend to have this car ready for the tracks..

regards

 

[GRNDSM]

Here we go again...

 

[23LBS]

what's that suposed to mean im asking a simple question???

 

[Tallen]

ITS A 4 CYLINDER! a turbo per 2 exhaust ports will not do all that great. it has been done and i see no benefits

 

[23LBS]

so i would benifit more an produce more power with one big turbo and not sequential ones... even considering turbo lag and all?

 

[Tevenor]

Yes, you can twin turbo your 4 cylinder 2.0l engine.
No, it won't give you any more gains over a single turbo.
No, it isn't worth the time or money.
Yes, it has been discussed many times.
No, it won't be more efficient and you will still have some lag.
Yes, Doug Derby from Doug's dynopower did this once upon a time.
No, he doesn't sell kits for a good reason.

 

[23LBS]

Thanks for input guys i apprechate it!

reagards,

 

[blackawdturbo]

Originally posted by 23LBS
what's that suposed to mean im asking a simple question???

This was just recently discussed in great detail that's why. Check the archives but you'll find it's not worth it. If you have too much time and money then by all means do it.

 

[L2RTSiAWD]

Yes this has been discussed in great deal before and in years past.

Check these threads.

http://www.dsmtuners.com/forums/showthread.php?s=&threadid=26874&highlight=twin+turbo

http://www.dsmtuners.com/forums/showthread.php?s=&threadid=24736&highlight=twin+turbo

Please search before posting as this took about 5 sec to find.