offthefront

Are you sure the 89 311 has TRS ? and the 88 has Bravo's? Seem the other way around? m

ThirdBird

It may actually be a minus. The 311 hull was originally designed for the TRS set up, engines forward more. This allows the boat to ride much more flat in the water. We with the Bravos experience porpoising and need planes in somewhat at all times to flatten the ride out.

Personally, if I were to buy a 311 over again, I'd get one with TRS. The TRS shifts like a dream and sets the bow down nicer. If I had to rebuild the tranny, so be it. I would miss the space in front of the engines though.

Having said that, who wants to trade a mint '89 454 Mag/Bravo 311 for a mint TRS 311?

go chiefs

well, pretty sure, looked at so many different things i could easily have made a mistake, what would make you think i may have it wrong? was the trs setup not offered in 89????

high cotton

Yes the 1989 3-11 was offered with the trs setup I have one and love it.The boat shifts great and rides smooth. The only problem I have had with it was a leaking bellow and water got to the tailstock bearing in the process of replacing it now. I have had both types of boats the trs setup and the bravo and would not trade the trs for anything.. Just my thoughts though..

go chiefs

not to be taken the wrong way by any means, but how do you know that the 311 hull was "designed" for the trs setup? i would never have guessed that to be the case or for that matter ever thought to ask the question.

ThirdBird

That’s a fair question. The short of it is that Formula said so. The long of it is that I deduced that before I asked them based on a few observations. One is that all that space in front of the engines (in a Bravo set-up) seemed odd to me. Two is that at the time the 311 came on the market, ’86 or so, if you wanted big power, you had to run TRS. They were putting 454s in front of Alphas but anything more than that would blow an Alpha to bits. Third was my previously stated observation about running attitude. The boat is just a bit too tail heavy with Bravos.

So, I had correspondence with Formula and they admitted that the boat was actually designed for the TRS set up. The Bravos work fine but the weight distribution of the TRS is better.

handfulz28

Weight distribution/ride attitude aside, what are the thoughts on a 420/TRS vs 365/Bravo? Correct me if I'm wrong, but isn't the 420hp rating a crank HP #? And the 454MAG-365hp is a propshaft HP#? So once you run the 420 through the trans and TRS, aren't you pretty close in "at the prop" power?

I'm no engineer, but understand a fair amount about CG. The TRS-311 carries engine weight a little further forward than a Bravo-311. BUT, you still have a pair of trans at the transom, plus a pair of drives that are heavier than Bravos correct? With a 150gal fuel tank in there, I just don't think there's that much difference in CG between the two. Not to mention the variables with passenger & equipment. Oh yeah, just thought about changing out exhaust; on a Bravo boat swapping iron for aluminum could make a huge difference.

As for ride attitude, that can change drastically with just a prop change. I know when I changed the Mirages out for Hydros, drive trim is totally different. But that applies to both drive types.

I've never shifted a TRS drive, and maybe I'm just super lucky, but my Bravos shift great. I think linkage and cables have a lot to do with that.

ThirdBird

Well, we have a friend with a 311 TRS boat - it rides flatter than our Bravo 311s.

As for exhaust, that's why I'm swapping out my cast iron manifolds for aluminum, we'll see.

As for props, I swapped out my 3 blades for Hydros. Big gain in midrange cruise. Gained 5 mph at 3000 rpm. But, I noticed no stern lift from those "stern lifting" props.

go chiefs

that is the answer that i expected, thank-you very informative


so i guess we are right back to were i started, personal preference, without regard for resale

got twins ?

Hey Michael,

Thirdbird does have some very valid facts on the running characteristics of a 311 with or without trs drives.

For example there are 3 of us with 1988 311s with all three engine and drive combinations available in 1988. At one point all three were bone stock . Mine has 330s w/bravos ... the most efficient but the slowest. Kris has 365s w/bravos fastest , middle as far as efficiency and Ted had 420s w/trs the worst efficiency and slightly faster than me.

Ted's boat lifted in the rear far better and ran cleaner in the water than the other two. The transmissions sucked up alot of horsepower which in turn cost him in cruising speed and efficiency. He always had to run approx 500 to 700 more rpm to cruise with us.

That being said he upgraded his power to 585hp a side and put on 26 pitch Bravo 4 props ....... totaly different boat now .... the runs the fastest hands down and is running alot less rpms than we are at whatever cruising speed we pick.

With the bigger hps and the bigger wheels he is turning this boat runs flat in the water with no azz end sink and little to no tabs ....

Just my 2 cents for what it's worth .....

Jeff