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Is it efficient to build a 1.8l 4 cylinder engine in a twin turbo configuration?

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hello everyone I would like to have your opinion on a subject: is it efficient to build a 1.8l 4 cylinder engine in a twin turbo configuration?

Hi Jean,

Depends what your end goal is and packaging space. When you say twin turbo, is that in a sequential forum or a compound set up (where one turbo feeds the intake of another)

Have you thought about a super charger and a turbo if your thinking of a lower down power boost? Or to reduce lag.

All really depends on what the goal is and then look at methods of implementation.

It will also depend on the turbo' size(s). Done properly, it should be very effective, done badly it's a huge money pit with terrible results.

DC, there're good results from some builders with a third variation - #1&4 to one small turbo', and 2&3 to the other.

Off the top of my head without doing the calcs I'd be tempted to say an 1800cc 4 cylinder or rather 900cc twin wouldn't flow enough air for a pair of common aftermarket turbos, at least at anything less than 9000rpm, a single turbo would be a more efficient way of doing things but it depends on your goal; if you're undertaking this as an academic exercise then yes its possible if you take a look at using a similar turbo to the Fiat Twinair engine. I'd expect this to be at its limit at say 140bhp meaning 280bhp - this is more than achievable with a single GT25/K04/VF28 or even a Rotrex C30 and would weigh a lot less and package considerably better. If driveability is a concern then as David suggested a supercharger/turbocharger combination could be the answer or even converting to a 48v BSG system with an e-supercharge from a late model JLR/Mercedes/Audi etc. if you wanted a bigger project.

Hello everyone and thank you for your answers. my goal: I want handling and performance with a lot of low-end torque (I also want a system with as little complexity as possible). Where I live there are a lot of very recent cars with hybrid turbos that are difficult to compete with .....

Scotty88 do you know the 48V Electric Turbo Supercharger from TorqAmp ?? it doesn't look very complex but is it reliable ....

Something we haven't asked, and should have, is exactly what you're using the car for and what you expect from it?

Depending on that, you're probably going to be better with a balanced build, so you can use what you have/expect to have.

Hi Gord,

sorry it's my fault I did not specify. it is a street car that will sometimes be used in street races.

The electric turbo is an interesting but expensive alternative (and I don't know if it is reliable over time).

The association of a compressor and a turbo is also very interesting but too complex for me to build (in my region nobody has his skills)

all you have to do is buy a good turbo with a twin scroll exhaust manifold.

what do you guys think?

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