I have always been skeptical of the Banjo style fittings if they could flow enough or had any sort of restriction, so I decided to do a quick test between 3 different style elbow fittings. All parts in the -8an to 8an size. I tested a Racetronix traditional style 90, an Aeroflow “full flow” 90 which has been my personal preference, and a podavelle banjo 90 from amazon. I used a fuelab 93905 at full speed and measured the amount of gasoline moved in ~20 seconds using a scale. At no pressure this pump flows roughly 1200L/hr (5.5GPM) so this is a very high flow test.

The results are in the pictures but long story short, they all flow roughly the same. with the Aeroflow fitting flowing slightly better (2-3%) than the other two. I would have no issues using a banjo 90 if space required it. It is also nice they float so there isnt any stress on the hose.

Follow-up Testing: I included pre-fitting pressure as well as tested a straight fitting for comparison. Results: The straight fitting and Aeroflow 90 flow basically the same with the same pressure drop (2psi). All pressures are very similar (between 2 and 3.5psi). The banjo had the worst pressure drop at 3.5psi with the traditional style 90 at 3psi. I bought a Radium banjo to compare but summit shipped the wrong size by mistake. Conclusion: You are still fine with any of them.