Out of Curiosity
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Well to shed a little light on the subject of wether stock twins or single is better. The stock twin turbos do an awsome job for a factory turbo that was never really meant to run more than 12psi-+ . Now as far as how they compare to a single turbo(60 mm p trim .58 a/r on up)the single turbo will smoke the stock twins.
Now you have to extend your rpm's so you have a more usuable power band(if you try to take off at low rpm's on a single turbo supra you don't need to be driving it).What I'm trying to say is that you drive these car's diffrent.
Also just like any high horsepower car when you start making more than 500 rwhp traction will be an issue but with the proper tire and suspension set up you can make more use of your new found power.
I do own a single turbo supra MKIV and have owned stock twin supra both auto and 6-speed.
I would rather have a small single turbo over the stock twins.
Now you have to extend your rpm's so you have a more usuable power band(if you try to take off at low rpm's on a single turbo supra you don't need to be driving it).What I'm trying to say is that you drive these car's diffrent.
Also just like any high horsepower car when you start making more than 500 rwhp traction will be an issue but with the proper tire and suspension set up you can make more use of your new found power.
I do own a single turbo supra MKIV and have owned stock twin supra both auto and 6-speed.
I would rather have a small single turbo over the stock twins.
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Aftermarket parallel twins are actually less efficient than a single with the same potential outputs. The reason being is that there is more disturbance in 2 exhaust housings than one. The disturbance which causes velocity losses is the inside surface area of the housing. Air hitting the housing is slowed and since twins have twice this area there is more exhaust velocity lost.
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The little 5.0 that could
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Originally posted by Mr 2
Aftermarket parallel twins are actually less efficient than a single with the same potential outputs. The reason being is that there is more disturbance in 2 exhaust housings than one. The disturbance which causes velocity losses is the inside surface area of the housing. Air hitting the housing is slowed and since twins have twice this area there is more exhaust velocity lost.
Aftermarket parallel twins are actually less efficient than a single with the same potential outputs. The reason being is that there is more disturbance in 2 exhaust housings than one. The disturbance which causes velocity losses is the inside surface area of the housing. Air hitting the housing is slowed and since twins have twice this area there is more exhaust velocity lost.
THE HAMMER
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so how does the stock supra regulate boost to the engine? Is it through a flapper gate system like on the RX-7?
Sorry I just thought that on the MKIV that both turbines were exactly the same size and fed 3 cyls each with the same boost.. thus being in sync.. not sequencial.. so at 3K rpm both turbines being exact sizing are at the same rpm producing the same boost, not that one was helping it to 3k-4k and then the other (larger turbine) was taking over...
I figured that they were both the same size and 2 of them because toyota
A: Has a ton of CT's already, didnt have to change much in their ordering cept maybe wheel trims and stuff (not sure on the size of the supra twins compared to the MR2 or something, might be the same i dunno)
B: Twin turbo sounds cooler than a big single (which they coulda gone for a T3-T4 sized turbine stock and gotten the same results... or maybe a T4 of some kind..) Also since the 300ZX was already Twin Turbo (since it has to be) and the skyline as well (prob for cheapness reasons kinda like the supra) were all TT.. having the supra be not Twin Turbo would hurt sales due to less coolness factor.....
I just thought that turbos on the supra were in tandem like on the 300zx / skyline
Not in sequence (1 then 2 after more RPM) like the RX-7 with its flapper gate switchover..
Sorry I just thought that on the MKIV that both turbines were exactly the same size and fed 3 cyls each with the same boost.. thus being in sync.. not sequencial.. so at 3K rpm both turbines being exact sizing are at the same rpm producing the same boost, not that one was helping it to 3k-4k and then the other (larger turbine) was taking over...
I figured that they were both the same size and 2 of them because toyota
A: Has a ton of CT's already, didnt have to change much in their ordering cept maybe wheel trims and stuff (not sure on the size of the supra twins compared to the MR2 or something, might be the same i dunno)
B: Twin turbo sounds cooler than a big single (which they coulda gone for a T3-T4 sized turbine stock and gotten the same results... or maybe a T4 of some kind..) Also since the 300ZX was already Twin Turbo (since it has to be) and the skyline as well (prob for cheapness reasons kinda like the supra) were all TT.. having the supra be not Twin Turbo would hurt sales due to less coolness factor.....
I just thought that turbos on the supra were in tandem like on the 300zx / skyline
Not in sequence (1 then 2 after more RPM) like the RX-7 with its flapper gate switchover..
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THE HAMMER
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Originally posted by Mr 2
Aftermarket parallel twins are actually less efficient than a single with the same potential outputs. The reason being is that there is more disturbance in 2 exhaust housings than one. The disturbance which causes velocity losses is the inside surface area of the housing. Air hitting the housing is slowed and since twins have twice this area there is more exhaust velocity lost.
Aftermarket parallel twins are actually less efficient than a single with the same potential outputs. The reason being is that there is more disturbance in 2 exhaust housings than one. The disturbance which causes velocity losses is the inside surface area of the housing. Air hitting the housing is slowed and since twins have twice this area there is more exhaust velocity lost.
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Originally posted by MR2driver
That was sure a lot said by a guy who isn't even turbo
That was sure a lot said by a guy who isn't even turbo
It was the only black/black for sale under 20 at the time... and it was in Texas. So keep your smartass remarks to yourself.
Last edited by SupraKid; Jan 17, 2004 at 05:14 AM.
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Originally posted by Mr 2
Aftermarket parallel twins are actually less efficient than a single with the same potential outputs. The reason being is that there is more disturbance in 2 exhaust housings than one. The disturbance which causes velocity losses is the inside surface area of the housing. Air hitting the housing is slowed and since twins have twice this area there is more exhaust velocity lost.
Aftermarket parallel twins are actually less efficient than a single with the same potential outputs. The reason being is that there is more disturbance in 2 exhaust housings than one. The disturbance which causes velocity losses is the inside surface area of the housing. Air hitting the housing is slowed and since twins have twice this area there is more exhaust velocity lost.
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Originally posted by TheShow50h
Ty, this question isn't to put turbo's on my car (although I wouldn't rule anything out
), but to just be more informed on the subject because I have a friend who just went to a single turbo in the t60 size, but that's not exactly what his turbo is, just the relative size of it. I just figured logically that the single wouldn't have near the power that the twin sequential had down low which is very important for a daily driver, but I guess when you start from a 70mph roll it doesn't really matter,
Ty, this question isn't to put turbo's on my car (although I wouldn't rule anything out
), but to just be more informed on the subject because I have a friend who just went to a single turbo in the t60 size, but that's not exactly what his turbo is, just the relative size of it. I just figured logically that the single wouldn't have near the power that the twin sequential had down low which is very important for a daily driver, but I guess when you start from a 70mph roll it doesn't really matter,
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Originally posted by SupraKid
When you go parallel twins, you have to remember you've only got three exhaust ports per turbo as opposed to the six ports for the big singles. Obviously, six ports create more exhaust energy than three, but the bigger heavier big singles offset this somewhat. With twins, two smaller turbos are doing the job of one large turbo and, apples to apples, the twins should spool quicker and, together, generate as much top-end power as the big singles.
When you go parallel twins, you have to remember you've only got three exhaust ports per turbo as opposed to the six ports for the big singles. Obviously, six ports create more exhaust energy than three, but the bigger heavier big singles offset this somewhat. With twins, two smaller turbos are doing the job of one large turbo and, apples to apples, the twins should spool quicker and, together, generate as much top-end power as the big singles.
THE HAMMER
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IF turbo A is one size and turbo B is (A*2) then its prob safe to assume that....
Twins of turbo A would have the same results as a single of turbo B..
This is a rough gestimate, but I dont see why it would be different...
Twins of turbo A would have the same results as a single of turbo B..
This is a rough gestimate, but I dont see why it would be different...
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