twin turbo setup for L series

[A to Z]

Have any of you had luck with a twin turbo setup on the L series.  Seems that 2 small turbo's might help with lag and really provide a movre livable street setup

[evildky]

There were a couple of well done twin turbo builds way back, Thaggard was one of them, cant remember the other name, search I'm sure it'll come up.

[Zetsaz]

12 hours ago, A to Z said:

Have any of you had luck with a twin turbo setup on the L series.  Seems that 2 small turbo's might help with lag and really provide a movre livable street setup

 

The issue with a build like this these days is that for the cost and effort you're really not getting much of a benefit over going with a modern turbo. The effort and cost to source or create a manifold for twins is more than creating a manifold for a twin scroll. that coupled with modern ball bearing turbos that spool faster and are more efficient than old designs means there's not much benefit (or at least not enough for most people to justify the increased cost and complexity)

 

That said, Todaro Racing did a nice twin turbo VQ37 build, and Koshikubi engineering out of japan has a REALLY nice Twin L series being built right now that could provide some inspiration you can find them on instagram @koshikubi_engineering 

[Dat73z]

Livable is subjective, with a modern properly sized single on the L paired with modern compression and tuning you're already spooling off idle with good drivability. Nowadays I think it comes down more to the novelty aspect, as the packaging gets pretty crazy in the s30 chassis. 

[Zetsaz]

Just now, Dat73z said:

Livable is subjective, with a modern properly sized single on the L paired with modern compression and tuning you're already spooling off idle with good drivability. Nowadays I think it comes down more to the novelty aspect, as the packaging gets pretty crazy in the s30 chassis. 

 

Can confirm. For reference @A to Z, me and @Dat73z have very similar engine builds (as far as the turbo bits go), except I'm EFI with stock L28ET compression and I'm still at full boost by the low 3k rpm range, and some boost not that far off idle.

 

At cruise speeds with my current gearing I'm going into boost the moment I push the gas pedal even in 5th. Around town it's not quite the instantaneous response my G37S had, but it's also lower displacement, lower compression, and doesn't have the modern VVL technology. With better compression I'm sure I'd be close enough to only notice if I was REALLY paying attention to rpm.

[Dat73z]

@Zetsaz full spool around 3k is also where my engine makes peak torque. For a "livable" street car you start running into traction issues as well. Punching it in 2nd on onramps I was lighting up 225 rcomps at 60mph lol

[240Z Turbo]

Twins should spool well if properly matched with the right turbo.  Keep the runners small using Schedule 10 1.25" Pipe (1.44" ID) for anything below 1000hp and this will keep exhaust velocity up to improve response.  I wouldn't go bigger than G25-550 and you'll need to play around with the A/R.  Knowing what I know now I would probably opt for a single turbo in a twinscroll configuration with something like a S362 SXE.  You'll have to find someone to build the manifold and it needs to be paired correctly with two independent wastegates.

 

My two twinturbo setups....