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After driving Xboy's GTR, the turbines kick in at around 3500rpm, and boy do they kick in :) however until you get there it's a little dead. So would it be possible to put a third small turbo or even supercharger to cover say 1500-3000rpm or so?

I've driven the Liberty B4 and the power comes on rather early <2000rpm with the first turbine, then the second at around 4000rpm.

My extreamly limited knowledge of car mechanics would say why not put a third smaller turbo on the GTR, I've heard of supercharged twin turbos on small cc engines, why not on a larger engine or even a tripple turbo? I am assuming that this concept is either ridiculas for some reason otherwise somone else would have done it?

well i dont' know if it really is possible .. i'd say no .. but i'm no expert .. if u wanted it to kick in earlier i'd say the choice of the turbos are more important along with the tune ... i'm sure the turbos can reach boost earlier .. say 2.5krpm with the right settings ..

It would be a bitch to design as the small turbo would have to ajoin the plenum of the 2 big turbos. PLus the constraints of the room in the engine bay, plus pipin to intercooler, i doubt in practice it would ever work, however in theory it would.

Anymore questions

The GTR's aren't sequential.. so you're probably out of luck with what you suggest.. maybe more appropriate on a TT Supra where its a sequential setup.

See the Liverty is sequential.. so its been designed as a refined daily driver and just driving around on boost most of the time with power always ontap across the range via two smaller turbos.

What you're experiencing on the GTR isn't a "gap" in the range, its just how its engineered as a non-sequential twin turbo setup.. to give full kick when you really need it - that is mid to high range power.

I think there was a concept RB26DETT motor with a supercharger (its posted on here somewhere).. it wasn't in a car for some reason.. I think it had to do with basically just fitting - as the supercharger pushed the width of the engine out too far to fit in an engine bay. Anybody correct me as to why they couldn't get it in a car??

NASA developed a 4million horsepower engine with one VERY large turbo feeding into another large single turbo, then that feeds 2 x smaller twin turbos (all in sequence) and makes 400psi boost. They now use these engines in their planes that fly on the edge of the atmosphere or statosphere. The turbos are 4 times the size of the engine itself, which is no bigger than a 4 cyl engine....

Also, I can't remember who, someone on here will, but a rally car driver had a Delta S4 which was supercharged and turbocharged. Best of both worlds....

My 25 to 30cents worth

Guest MFX_R33

Twin charging is alot of stuffing around for very little gain. If you are getting good boost by 3000rpm that is fine. All you need to do is to adjust your driving style. With a redline of 8000 (you could even push further than that), you have a rev range of 5000rpm. That is quite a good useable rev range for most driving.

Jeff.

Yes it is a bit of a dreamer idea. but thought I'd check it out. Looks like the concept is fine, and a suprecharger would be the way to go, if it would fit :(

Don't mind having the power up in the higher rev range, but would like a bit more down low for just "normal" driving. Would be ideal as you could then have nice progressive power with the option to give it boot when you want to really bring it on :D

Guest INASNT
Originally posted by rb25

NASA developed a 4million horsepower engine with one VERY large turbo feeding into another large single turbo, then that feeds 2 x smaller twin turbos (all in sequence) and makes 400psi boost. They now use these engines in their planes that fly on the edge of the atmosphere or statosphere. The turbos are 4 times the size of the engine itself, which is no bigger than a 4 cyl engine....

Also, I can't remember who, someone on here will, but a rally car driver had a Delta S4 which was supercharged and turbocharged. Best of both worlds....

My 25 to 30cents worth

big boats use the same system feeding compressed air from 1 turbo into another in another etc

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