# Sequential Turbo set up.



## MikeBrown (Nov 19, 2009)

Looking to get some talk going on this. This is not about twin turbos it is all about sequential turbos. I think you are all familiar with the concept. I am just trying to get some talk going about specs. I have a 24v vr6 and im batting ideas on turbo sizes. 
And for anyone that dose not understand what im talking about pictures.
 
The small turbo feeds the big one giving less lag and more boast faster.


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## Jeebus (Jul 8, 2001)

*Re: Sequential Turbo set up. (MikeBrown)*

Honestly with the new billet wheel ball bearing turbos from Garrett and Precision these setups are becoming less and less necessary. Even large turbos are beginning to have great spool up. Buy the right turbo and you'd save yourself a hell of a lot of hassle and money. 
Just my .02c


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## TBT-Syncro (Apr 28, 2001)

*Re: Sequential Turbo set up. (MikeBrown)*

sequential is pointless on a FWD car. all you'll be doing is creating more wheel spin.


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## Jefnes3 (Aug 17, 2001)

*Re: Sequential Turbo set up. (MikeBrown)*

The pic posted relates to COMPOUND charging...
Typical boost for this type of set-up is 45-70+psi.
Proper turbo sizing: Reference the pic
Turbo 1: same size as you would for typical street VR6 Turbo project. Something like, 60trim To4E, GT30, 60-1
Don't go too big on the turbine housing.
Sized for 350whp.
Turbo 2:
pick turbo designed for ~350+whp motor, to make 7-800whp on 'low' boost.
Something like: T80, S476, GT45, GT47
To Start:
Set both turbos to run 2:1 pressure ratios. (this is equivilent to ~15psi on single turbo set-up)
This will yield approx 45psi boost pressure at the manifold.
How: compound boosting, 2:1 and 2:1 will make 4:1 net, less atmophere gives you 3 bar boost, or roughly 45psi
my opinion(s):
expensive science project. LOTS of details not even mentioned.
Also I'd plumb it differently:
Big turbine before small turbine
Big compressor feeds small compressor
small compressor feed engine
A true sequential setup 
use 2 ~small-medium sized turbos.
100% exhaust/intake flow is thru one turbo, for quick spool.
When some power level is reached, bring the 2nd turbo online.

-Jeffrey Atwood


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## nothing-leaves-stock (Mar 1, 2005)

*Re: Sequential Turbo set up. (Jefnes3)*









[IMGhttp://farm4.static.flickr.com/3325/3182424891_0cc0455c24_b.jpg][/IMG]


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## DieGTi (Jun 19, 2001)

toyota intake manifold


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