I just purchased a brand new 36 hp prodrive. Its a tall transom engine.
i had it on a 19.5 inch transom, and the engine seemed to do pretty good in reverse. I swapped boats, and the transom on my new boat, is 21.5 inches. it doesnt seem like much of a difference, but theres a big difference when in reverse. I dont get as good of a grab in reverse with the taller transom.
Before i decide to cut the transom or make any modifications, can someone help me? maybe give me info on whats the best thing to do? Would cutting my transom down 2 inches be the best thing to do? Any info is greatly appreciated! Thanks again!

Pro-Drives are designed for a 19.5" transom. If you want the best performance out of your motor, thats what your transom height needs to be.

so, best bet would be to cut the transom down right? i wouldnt be able to think of anything else thats better.

Or a 3 blade prop. Blades are shorter

I really had the visual that the actual cavitation plate is supposed to go under the boat. am i right? or is it supposed hit the transom?

My cav plate rubs the bottom of my Prodrive boat/stops prop from hitting

wrong transom height...your gonna have to cut it down. There is nothing else you can do. well you could buy a boat with the correct transom height or cut yours down.

So, it should be cut down to 19.5 inches. and my cav plate should be able to go under my boat?

How many more times do you need to be told the same thing.

lol delta. I have a buddy who has a 27 and his cav plate doesnt go under the boat. some say it should be like that, and others say it doesnt. im just trying to make sure before i do some cutting and fabbing up.

call prodrive, they will tell you.....trimmed all the way up when you spin the lower unit, cav plate and all go under the boat....you can trim down a little but you dont want the cav plate rubbing or its hard to steer. Whatever anyone tells you it dosent matter, you should always go with what the manufacturer tells you.

Thanks, thats what i was looking for. i appreciate it!

It will put a dint in the back of your boat if not a hole trim it up . I fount out the bad way

I have a PD X-series boat an if u trim the motor down too much it will hit the back of my boat in reverse u just have to figure out how low u can trim it

20" max for a PD.

I'd go 19 and then you will be able to shim it back up 1/2" if necessary. Every boat will run different even if they were popped out the same mold. I have a boat in the yard that runs best at 19 inches.

what about transom angle. Are they different. I have seen the wrong transom angle do this.

I agree it would make since for it to go under the transom but I have a Prodrive (factory) boat and motor with 21" sides and the cavitation plate will hit the back of the transom about 2" from the bottom, they even have a double layer of aluminum in that spot for added protection. Bug has one with 18" sides with a taller transom, same thing... These are factory built Prodrive boats for Prodrive tall transom motors. It's basically up to you if you want to cut or not, to each his own...

I had a factory pd and my prop or cav plate never hit my transom if i was trimmed up all the way....when i trimmed down to get more push instead of lift it did.

Correct, you can trim down to where the top of the motor is just about level before it hits....

wonder if those with the small rake at the bottom of the transom have this problem. The rake is about 3" up, might miss it.

cav plate might not hit it but prop would......

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It works really well, I have a few different designs out, but this is one of the better performers. When you lift up it has more room to clear its self and the longer/ higher rake lets more shit slide under it rather than piling up in front. Also if you look at the pic above that motor has a 1/2" spacer between the transom and the clamp. This also allows you to make the front the skeg longer. This combination of skeg and modified cav plate work very well together and weed cutter turns a normal props salad into coleslaw.

Had same issue with a PD and gator trax lived with it for a year and had KP cut it to 19.5" Now I kick myself for screwing around with it for a year.

Now im thinking about putting a jack plate on the boat. It'll set the engine back only 3 inches or so, and i will have it to where it will be dropped 2 inches or so. anything good or bad about a jack plate for a prodrive? its not hydrolic or anything, just something to lower the engine!

Just cut your transom down. Uncle J is doing it for me now. Its not worth fooling around with the jack plate.

Want to bring this back up. Building my new rig in shop now. What actually is the best transom height for a PD 36 long shaft?

19-19.5, imo

Pro-Drive will tell you 19.5

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