do you think i cold put a pair of 200 evinrudes on the back of a 18ft manta?
 

i just came across a sweet 18ft manta, seems i have a thing for them after buying a 32 manta cc yesterday. lol

i would think a pair of 200 o/b s would weigh about the same as a sbc and drive, and about the same hp... what do you guys think? thx for any info, rm

it will be fast!

fast or stupid and uncontrollable fast? lol

What's the worst that could happen. You would have to start from the beach and end at the beach like a water skier. LOL. Look out Outerlimits. Your speed barrier is about to be broken.

lol... the manta has a notched transom, but i can fabricate a tandem stand off bracket to mount them. i was more concerned about the weight...rm

A buddy had a 24 carrera that someone converted with a 20" bracket and twin merc 250's I think. It was dangerous over a jet ski wake!

Got a Pic of this 18' Manta?.... As a kid we had a 16' Manta ( Knockoff of a 16' Donzi with a different deck) we had a 90 HP Merc inline 6. it went high 50's trimmed up. I can't imagine 2' longer handling 210 more HP and the added weight on the back.. When we sold the 16' Manta the guy put a 2.4 on it. I Rode in it with Steve Curtis Driving, It went High 70's and he would do "U" Turns going WFO :0 .. He'd trim it till it Peaked in speed & Rpm then trim it down and crank the wheel.. His Ballz are Bigger than His Brain (And He's a Pretty smart Guy)..Anyway, Show me this 18'.....

You can't compare the weight of two outboards with sterndrives. With the inboards the weight is way forward of the transom. When putting twins on the transom you will need to mount them hard on the transom. Any set back will create a problem with bouyancy and give poor rough water handling.

I believe the 18 Manta you are talking about is the one a gentleman that I know is selling... Is it brown all original ? If so, that boat is completely original....... Cool looking boatyard and super different as they only made like a handful or so....this one ?

http://miami.craigslist.org/mdc/boa/4011431264.html

The issue won't be getting on plane - it will be coming OFF plane. I think your motors will be getting a bit wet. There's just not enough ass back there to maintain the floatation for that weight that is on the wrong side of the transom. Big difference between the SBC on the forward side and two OB's hanging back 20" (and that's at the front of the motor.) The Manta hull is actually 17' and is a copy / pop of the 16' Donzi. Not much beam back there.

There was a 21' Superboat in Ft. Lauderdale back in the 80's that had two 2.4's. They were flush mounted and still had issues with the motors getting splashed.

ratman.... You'll sink it hahaha Even a single 200 is going to need a little attention coming off plane. Especially with a set back. That Manta 18 in Miami has the motor sitting on the transom rather than set back, so take that into consideration. The setback effectively leverages the back of the boat even farther into the water and changes the balance point. The result is going to be pretty nose high both getting on and off plane with a single. With twins, you have 600+ lbs hanging 12-18" off the back, the wave coming off plane will literally drown the motors

yes that it! i think i have someone that can go look at it for me tonight... do you know the boat well? any issue with rot in the stringers or transom? i plan ti repower it immediately, i have a 225 i can stick on it. thx for any info, rm

i have a pair o rude 200s is the only reason i was contemplating this swap...thx for your input guys. look like im sticking a single 225 on the back of it...

I don't know the boat to that extreme but its 100% original... And super rare!!!!

thx for the info. i have a guy looking at it tonight at 7 pm, i think it will be kinda cool having an 18 and 32 manta... in colombia outboards are the way to go for parts... no big or small block chevy stuff down here at all...rm

With a 225 that boat will FLY!!!

John-rudes are even heavier than the 2.4/2.5's. If you want radical take one of those V-8's off your 32.' That would make more sense.

Hey ratman, clear you inbox. Tom F

im doing this thing on a budget, i will scrounge up what i can in the 200 to 250hp range, freshen it up and have at it...

im keeping the 300s on the 32 manta, when they get tired they are going to monty racing for the 380hp treatment then back on the boat. i have a pair of rude 200s i will hang onto as spares so i wont be down more than a day or two if i have any sort of problem with the 300s...rm

cleared...

I looked at an 18' Manta once and it seemed rather low in the water. I do not think putting more than one engine on it is a good idea, especially a big fat one!

uh..NO!!