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^^^^

Its a very smart idea back in the days tho. It can work our really well just depending on how it has been set and twicked. If I ended up owning a supra or building a sequential setup for my guinea pig, I'll sure be able to make top HP with minimum lag.

I can't think of any company that makes a sequential setup really worth all the effort.

With modern turbo design, a single just makes everything neater and if you're that hung up on milli seconds of lag, you shouldn't be on the street anyway.

Ever humped the exhaust manifold, turbos, gates, valving etc from a 2JZ. It's bloody heavy and stupidly complicated.

They're prone to sticking so the primary turbo ends up doing all the work, secondary doing nothing.

You think your Skyline exhaust manifold studs are working hard, they're holding a fraction of the weight compared to a sequential, and all the additional manifold struts don't help with the thermal expansion.

In a truck engine with maybe a 1000rpm usable rev range, the complications of sequential and exhaust recovery turbines are accepted whereas any modern car engine has a much larger usable rev range.

Cat C-15 Acert went the sequential route, Detroit DD15 went single turbo plus exhaust recovery turbine.

Cat is buried under lawsuits, clients suing for loss of income...........while MTU Detroit powers on.

yeah sequential is great IF its working correctly, mazda (13BTT) and toyota (1J) gave it a shot but i believe they both went back to singles (also more cost efficient)

you are quite correct, the 1J no sequential turbo but the 2j did

jc cosmo had sequential (1990 to 1995)

toyota supra mark 4 had sequential

mazda rx7 fd3s had sequential

Well if you spend enough time on adjusting the valves and actuators there is no dealt that the sequential system can work perfectly. Most of the setups are made for stock turbos at factory boost level and it works fine on the setup its designed for.

Interesting thread

Im not familiar with RB26 motors and twin turbo setups so my question is this. Being a parallel setup, RB26 motors have two turbos that are the same size and share the work load at the same time but with a sequential setup you have two turbos of varying size and the smaller one works at the lower rev range whilst the bigger kicks in when you work up the rev range. Is this correct? And are all RB26 motors (32, 33 and 34 GTR) parallel setups? What about the new GTR?

Cheers guys

Sequential is where two turbos the same size are staged.

Ie the 2j below 4000rpm (ish) all 6 cylinders blow through one turbo. Above that. Both turbos are used there is a noticeable dip in the power at the change over point.

A small/large turbo setup is compound turbo charging. Where the exhaust outlet of the smaller turb feeds to turbine inlet of the larger. Same for the intake (cold) side

Cheers guys,

PIGGAZ, I received a response from a forum member saying that as the R35 is a V6 and not a straight 6, the setup would be different. But Im assuming that despite the difference in setup, it will nonetheless be a "Parallel" setup yeah?

Cheers

Cheers guys,

PIGGAZ, I received a response from a forum member saying that as the R35 is a V6 and not a straight 6, the setup would be different. But Im assuming that despite the difference in setup, it will nonetheless be a "Parallel" setup yeah?

Cheers

One bank of 3 cylinders feeding one turbo with no funky valving. Same same on a straight 6 like the RB26. On either engine there is no "staged turbo" arrangement.

Sequential is where two turbos the same size are staged.

Ie the 2j below 4000rpm (ish) all 6 cylinders blow through one turbo. Above that. Both turbos are used there is a noticeable dip in the power at the change over point.

A small/large turbo setup is compound turbo charging. Where the exhaust outlet of the smaller turb feeds to turbine inlet of the larger. Same for the intake (cold) side

Not true. 2JZ was indeed sequential with 2 equal sized turbos. Rotaries though, were sequential with small and big turbos. The turbos still flow in parallel, its just that they are staged so that one doesn't come in until higher revs/more flow.

Compound turbo arrangements require that the air flows through first the bigger compressor stage, then the smaller compressor stage, whilst the exhaust flows through first the smaller turbine, then the larger turbine. Depending on how much work you need to do on each of those compressors, there is probably some freedom as to which turbine they are each connected to. There is also some freedom to use more than 2 stages, and to variably choose whether to compound all the stages of both sides, or run the turbines in parallel, or various other options.

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