34s fine for a mild A14 or 130-140hp max all been perfect
38s on an L series think about twin hitachi 38s vs L18SSS
2 more extra 38s now less resonance issues, better response,
more torque & power setup properly compared to the SUs.

There is a KA24DE 2.4L running beautifully with R1 carbs

https://www.youtube.com/watch?v=-Bm_kN25WmQ
first start
https://www.youtube.com/watch?v=ptZW68fahPI
exhaust sound
https://www.youtube.com/watch?v=ybEvBdp3AVs

Depending on needs a 4 x 34mm can flow enough for 90%
of applications for the A series which usually are around
90-140hp ate depending on whats in your wallet.

A supercharger with a single 38m can likely also make 130hp