2nd turbo to RB25DET

[Rasi]

Your thoughts,

While riding my bicycle home last night I had a brain wave, whether it being from lack of oxygen to it or something.

I am lead to believe (from information in this forum) that the series 1 turbo cannot be safely boosted above around 12 psi. This seems to be the weak point in the engine system to allow more boost as the usual way to increase boost would usually be a larger or hiflowed turbo. Would it be possible and economic to add another series 1 turbo (as it is relatively cheap 2nd hand) to the system so that both turbos do not have to work as hard to increase the boost to say 18-20 psi? Can the internals of the engine handle that?

Obviously, the following would need to be in place; larger intercooler, air intake, exhaust, upgraded fuel pump and injectors, and an engine management system.

What are your thoughts on this system, possible costs of the added turbo only, and any other constructive thoughts?

Mike

[blind_elk]

To get 18-20 psi in the system, BOTH turbos would need to be pumping 18-20 psi. Its a simple law of pressure - the pressure in an enclosed space is distributed equally in all directions.

[browny]

Forgive me if this is a dumb question but can turbos be put in series?

Even if it could be done I dont think it would be that great a proposition after adding in the cost of custom manifolds and pipework and whatever else you would need.

[turbomad]

I think what your thinking of is like the system that those race trucks use where 1 turbo feeds boost into the 2nd turbo's intake thereby increasing the final boost the engine recieves, really wouldn't work on stock R33 turbo's though, and not practical for a street car.

Another idea would be to setup a 2nd turbo after the dump pipe of the first so that both turbo's recieve all the gas flow of 6 cyclinders, hence no extra lag but double the airflow, similar to the Supra twin turbo.

[Guest INASNT]

y not just buy a gtr and save yourself all that time,trouble and money!

[Maxx]

well, he own a Silver '4dr' R33 GTST , 4 door GTR is very rare (very expensive too)

[MattyB]

why not just get a t78 or something nice and big.

[Blackness]

Rasi has a point with the "cheaper" price of std RB25 turbos .......

I had given it some thought as well ... however the cost of a custom six cylinder dual turbo manifold would make it a lot cheaper to go a different turbo ....

[JimX]

With all the manifold work you'd have to do, plus the price of the extra turbo, you're probably better off selling your original and just buying a bigger turbo.

[Rasi]

Yeh,

Like I said, it was one of those thoughts that may not have any substance as there was a lacking of oxygen from riding my bike. Just a thought tho'

A 4dr GTR would be great as the cars I buy are required to have certain criterias to be filled (due to the wife's demands) and 4 doors is one of them. Luckily boot space wasn't, but now is. Looks like this cars here to stay.

[JimX]

You can get 4 door GTR's but they cost a bomb. If you're after more power, just sell your old turbo for around $500 and buy a new Garrett for around $2500. It'll work out to be around the same cost as adding another turbo (assuming that's even possible).

Also, for some reason insurance companies don't like twin turbos put onto cars that didn't come that way from the factory. My insurance company don't care that I've got an aftermarket turbo on, but they wanted to be sure that I didn't put a twin setup on. They don't actually care what the single turbo is though! Can't wait until I can afford a T88 For some stupid reason they seem to think that going from single to twin turbo makes it insanely powerful. I didn't bother telling him that it's often the other way around.

[meggala]

why not fit an rb26 to your car I know its not cheap but you get twin turbo's lots of power etc.

meggala