Sequential Turbos RB20DETT

[R32 GTSTT]

hey guys, I posted some information about my RB20DET with twin stock RB20 turbos, but ive been hearing from alot on people that is is going to be extremely laggy. So ive decided to make to the turbos in sequential.

We are going to put a valve in the exhaust manifold so that when one of the turbos is spooled up, the valve will open and allow the other turbo to spool up.

i believe that another 1 way valve will be needed where the compressed air is , so that it wont travel into the other turbo while one is only spooled up.

if anyone has any comments of knows how this works or if this will even work or ANYTHING please post

thanks

[BHDave]

If you have two 3-1 manifolds so three cylinders are feeding 1 turbo each it wont work. You will be wasting half your exhaust gas.

To get the boost response you want you would need to have a 6-2 manifold that has a shut off valve to one turbo to allow the other to spool up normally, probably slower than normal because of the messy manifold.

You would then have a massive flat spot when you open the valve because you halve the gas flow to the turbo thats making the boost and have to wait for the other to spool up. Plus there is a hell of a lot of plumbing, have a look at a factory sequencial car, plus the fact that sequencial cars have 1 small and 1 large turbo.

You will be better off with two smaller turbos on two 3-1 manifolds. get a pair of GTR turbos if possible, or a pair of T25s and modify the manifolds to a T2 flange. You will not get a good response from the 2 RB20 turbos, 5000rpm plus.

Sorry mate

[BOOSTD]

Is there any OE smaller A/R Exhaust housings that will bolt onto the RB20 turbos???

[BHDave]

I think the RB20/25 turbo share the exhaust housing and turbine wheel and it is one of the smallest on the mid frame turbos.

When you get smaller, as in T25/28, the turbo has a smaller core. I don't know whether one of the housings off these turbos will fit.

You'd still need to change the flanges on the manifolds though

[slip]

There is one question you need to ask yourself.

Why?

[R32 GTSTT]

Does anyone know exactly how sequential turbos work, and wats involved in doing it?

[Squizz]

Originally posted by slip

There is one question you need to ask yourself.

Why?

The same could be asked of an Aussie 31 driver spending way too much on brakes and suspension...

[Morgs]

Originally posted by Squizz

The same could be asked of an Aussie 31 driver spending way too much on brakes and suspension...

.... but that is such an easy concept to understand... brake and suspension upgrades so he can go faster...

... two turbos that are oversized, attempting to make a never seen (at least by me) setup on a RB20DET, hard enough to get the twins running without messing around with sequential setups... im sure someone more technical minded could expand, but I can't really see it being a viable exercise...

The simple (and cheaper) option would be as suggested smaller twins or a bigger single!

[Squizz]

I was just saying why should the guy have to justify his mods to others. Slip feels the love

[Morgs]

Slip always feels the love

You are dead right though, its his car and he can do what he wants... I'd just choose the easiest way

[slip]

Shut up squizz.

He needs to ask himself why.

He is talking about crazy plumbing valve setups for two turbos, and he doesnt even know how sequential turbos work.

Squizz - my brakes and suspension were suitable, realistic, and researched. They were done, and work extremely well. Very different to this crazy idea.