How does transom angle play a factor in how well a surface drive performs on a boat?

What seem to be the average angle on most MM rigs; and what angle works best for the different brands?

I have a custom hull and my transom angle is about 17 or 18 degreez, Transom angle has a huge role in how your mud motor performs.......

This is a big factor on why the average ribbed hull does poorly with a MM cause
it's angle is setup for the average outboard....

Short answer - LT won't care about angle as much as height - balanced SD won't either
but the weighted back designs need a specific angle to work right and each has a different
"ideal angle" - which you find on their brand hull.... Best reason to buy a matched set
or use a custom builder who knows how to tweak exact height - trailing edge design - and
also angle - for your MM brand of choice ! ! !

How does the different angle cause problems?

Transom height needs to be right. Trim won't fix a long shaft on a 16 r 17 r 18 inch transom.
If u want 2 get the extra speed at wot get a hydraulic jack plate.

i wasnt referring to height. strictly just angle

I do understand the whole transom height game; but was questioning on the transom angle setup.

In general shouldn't a surface drive be able to run on almost any boat that has a transom angle other than straight (outboard setup only), just by adjusting the trim?

You need both height and angle to be right to get full performance!! Trim helps some but depending on angle will hurt you , either won't go low enough or high enough!!

All I know is my GDSD 35 and my MB 35 both like 23 degree transoms