Should I put M-80s on my 18?

[Bushwacker]

The trim tabs are still very effective on lateral trim (roll angle), although they are probably a bit less effective at controlling running angle since the boat is now significantly stern heavy with a 430 lb motor set back 30". However motor trim has MUCH more effect on running angle than it did before with a 20" motor hanging on the transom, so tab effect on running angle is somewhat irrelevant! I suspect that the 30" longer lever arm called the bracket is the prime cause, but the longer 25" shaft motor may also have something to do with it.