So I bought a 88 10 meter last year & I love it. It's got 600 hp 509's & TRS drives. My dad also has an 88 12 meter that he upgraded from #3's to #5's last year. They were just rebuilt before he found the 5's. Was kicking round idea of putting the 3's on my boat. Was wondering if anyone on here has tried it & were the results worth all that work? My TRS's are like brand new with no problems. Would it slow boat down, they say takes more power to spin a 3? My engines are farther foward in my boat than his, so would have to deal with that.

The Konrad, replacement for the TRS would be your best way to go. Parts for the #4&5 are becoming harder to locate, I would imagine #3 are not far behind.

not sure your engines are further forward..same transmissions and engine placement..konrads are your best bet hands down.and a direct bolt up..awesome pricing going on....

To convert to 3's from TRS, you are correct. The engines have to move back like 2''. So you will need to drill the stringers. At that point, you will also probably want to raise the engines height wise too.

Personally, if you have the #3's, go for it. Most it might cost you is a couple grand in misc parts, like ssm tailstocks for the trannies, and transom assemblies if you dont have them. Thats ALOT cheaper than spending 20-25k for new drives.

Set your propshafts about 1.5-2" below the bottom, you may have to notch the rubrail. The boat will more than likely go faster than the current trs setup, and throw a cool rooster tail. The 3's will live forever with 600's in a 10 meter, and if you wanna step up to 750's, they will work fine for that too.

Mild, have you run a set that high? With or without a notched transom?

Yes, my 38 has Ssm iv's . Was a Trs boat. Propshafts are 1.5" below the bottom. No boxes, notched transom. With 4 blades prop slip is 10-12 percent.

Do you think the 4's different skeg and cavitation plate make a difference? Just asking because I'm getting ready to start cutting on my hawk for the 3's. I think I'm going with 2.5-2.625 below.

There was a guy on here with a 10 meter with iii's and very high x . No boxes. I wanna say with about 425-450hp he ran mid 70's.

Lil red you may not be able to go that high on your boat, being 40ft and heavy, deeper drives may help carry the bow better and net more speed. No cavitation plate on the iv's. I think your boat would do well about 3" below the bottom. But that's just my thought , and I am by no means a rigger !

Thanks for the info! Good points that I was forgetting. I had originally decided on 3, then said I could squeak a little more..... Forgetting that I'm trying to push a barge!

You switched yours over fro TRS, yourself or did you have someone do it? How much of a nightmare was it? We have everything except tailshafts. My dads boat is a 88 12 meter. It had 1.68 ratio when he bought it new. Couple years ago he had drives rebuilt and went to a 1.50. Now it's got 5's with 1.50 and 1000hp, and is quite a bit faster. What ratio you running? Shortening the tailpipes seems scary.