Does anyone know if the mid-pipe from the GS350 will fit the GS450h?
They have different part numbers, but from visual inspection and measurements, they *appear* to be identical

The exhaust manifolds are definitely different... the GS450h is a pure log manifold, likely to clear the HV cables, whereas the GS350 manifold has better design for flow. So I was just wondering if the GS350 mid-pipe is different as well.

Thanks!

 

Are you sure that the gs350 has a different manifold?

 

GS450h manifold - notice the log-type collector where the exhaust port is almost attached to the pipe, the exhaust slams 90 deg into the collector.


GS350 manifold has at least some semblance of primary runners, the flow looks much better than the GS450h version

I have studied this for months... our GS450h's came with a log-type collector, likely for clearance issues. Maybe the GS350 manifold will net us 5-10hp somewhere due to the smoother transitions... not even sure if it makes much of a difference, since ours is mostly a low-ish-RPM engine

Any thoughts?

 

On the note of engine differences - the 2gr-fse in the gs450h also has different intake VVT.

If the pic above is from an OEM gs450h manifold - looks like we've got another difference to explain the slight horsepower downgrade.

 

Thats interesting, similar to the GS460s log style manifold compared to the LS460s.

It means the 450h would benefit even more from a long tube header upgrade among other things.

 

The other consideration is that... we poor hybrid folks can't rev our engines past 5500rpm due to the MG1/MG2 tether until we hit 100+ kph.

I just can't figure out if the mid-pipe is the same... otherwise I'd just buy the GS350 manifolds to try

 

Uhh...
@rl9010 might have some input?
I think you've seen his build thread, but if not - go there now. Not a midpipe, but I'm pretty sure that he's researched the options.

Can't help much other than that, GS350s have sadly never been sold officially here and I wasn't even aware of the manifold shape differences (silly me).