Standard Midsection VS Offshore Midsection

[Krazymaan]

If your not building a boat to go beating across the rough ocean and circuit racing. Is there any benefit to even own an offshore midsection.
Saying you are using 1 piece adapter plates and solid mounts for both comparisons.
Maybe you want to do a couple of 1000' drags a year and mostly lake and river runs and play time the rest of the time.
I have both and the offshore is so damn heavy compared to a regular midsection. I would think that would actually slow you down in the 1000' and it definitely will press your transom down in the water an extra 1" or so.
Instead of the typical its a stronger unit comment and where the exhaust exits. I don't really recall anyone that has broken their regular midsection.
I know you have twist and flexing going on, but like i said not a circuit racer or ocean racer. What are the odds of it actually breaking? Slim to none? 20%?

[Primal 98]

No sure if this is relevant or not, but I was once following a 2.5 powered lightweight on flat water at around 85mph. the 2.5 through a blade (I seen the splash as it landed), then seconds later the gearbox was launched off due to the vibration. Unfortunately I did not see the failure point of the gearbox (studs, casing or the mid itself) as we were racing and the boat was recovered and left before we returned to the dock. I am not sure if the offshore mid is any stronger, or just the clamp/brackets etc., either way, it shows that failures can happen on flat water under these circumstances. Anyone else shed any light on 2.5s throwing gearboxes off the mid after propeller failures, and whether the offshore mid is beefed up to prevent such failures?

[WillySteve]

I've run the early single ram fishin stuff my whole life with no problems. Ran over Stumps, ran N20 and totally abused them with no mid problems what so ever! Can't say about all the other stuff bent and broken!
JS

[Dave S]

Sand cast.... diecast. When Merc makes a few it's sand cast ... a lots of them diecast. Sand is thicker... not sure of how much stronger, maybe less brittle.

[Krazymaan]

Good to know. So basically if your just a weekend warrior on a lake, having a standard mid might be a weight advantage. That was what i was thinking too. Besides if your going all out then there is usually a safety crew there to save you and catastrophic failure doesn't often seem to be in the midsection area.

[WillySteve]

Sand cast.... diecast. When Merc makes a few it's sand cast ... a lots of them diecast. Sand is thicker... not sure of how much stronger, maybe less brittle.

How does that affect the mid if they're the same between OS and Fishing? Do we know for sure they are different?

[Onetime]

I've seen a couple of bass mids break in two. Break right below the exhaust plate bolts.
Boat was not babied but not abused either. Just wake crossing.

Thinking it it also depends on how fast the boat is and what kind of horsepower relating to the loads being put on the mid.

[Krazymaan]

nothing crazy just something like an ultra light boat with 350hp. that should do it.

[mjw930]

Are we talking a 3L mid or an older one? I believe the 3L “bass” mid is significantly stronger than the older “bass” mids, at least that’s what I was told by Mercury last year.

[Krazymaan]

For me I'm just talking about 2.4 L stuff maybe older 2.5 stuff too

[90 5.0]

nothing crazy just something like an ultra light boat with 350hp. that should do it.

Ultra light boat with “only” 350 hp, I wouldn’t do that without a 15” offshore mid but that’s just me.

[Coryc]

I have always had a bass mid on my 21' Superboat. This year I switched to a late model smoothback o/s mid. And there is a huge difference. If you put a bass mid and an offshore mid side by side and looked at them from above standing the mids straight up with no adapter plates you'll realize the offshore is at least twice as strong, if not three times as strong. Much stronger mid all around. It looks badass and it sounds badass too. But with that aside I believe it's much stronger. If you are putting a motor together you might as well put an o/s mid on it. It's a lot cheaper to do it now then to realize you need one or to have something happen to the bass mid. I only use my boat as pleasure and I don't drive the boat overly hard. Just my opinion.

[Krazymaan]

I have regular mids, bass mids, a ridge back and a 280 offshore and a custom made lightweight offshore mid. I was just thinking about how many times i've heard of a regular mid break apart upon regular/heavy use. None really that i know of. Not including home made bass holes, drilled mid's, add a snout mids or any other home brewed slice or drilled into mids. Those are alll susceptible of failure for obvious reasons. Thats why i'm not really interested in those ones and thats why i am interested in peoples experiences with regular mids and did you ever break one.

[Onetime]

The "regular" mid and the "bass" mid are the same mids. The bass mid is drilled for exhaust relief at the factory and uses solid mounts.

Keep in mind that mid was engineered and designed in the 80's for 200 horsepower engines. It's been used by the factory up to 280 horsepower. Putting 350 horsepower to it I'm thinking is going beyond whatever engineering safety factors it was designed with. Don't get me wrong as I'm sure it will work but it's going to break easier and sooner with the high horsepower.

Look at the 15" swivel bracket that is being used on 3.0 liter engines and 400 four strokes now. They're breaking pretty regularly. It was originally engineered for a 2.5 liter.

[Capt.Insane-o]

I've broke a half dozen fishing cans. Mostly on my hst. One cracked by a lower mount, the rest right under the power head studs. I'm rather fond of the boats cornering ability though.

[RIVERRUMMER 70]

260 on a bass mid will break and ive seen more than a few.
watched a good friend dive for his new sporty after one weekend on the lake .....never found it....:nonod:
if your real easy it might last a while but who is easy on a 260 with a lead flip flop? 350 hp fugetaboutit!
if you are that serious that 20lbs is a factor then 15" ros or drag mid is the way to go, otherwise the 280 os mid is what i would use with
pump in the boat vs 3ram bass is not a big deal .;)

[WillySteve]

I hope like Hxll y'all ain't jinxin'me reading all this.
My current mid came on my '95 260 Bass and never had a problem.....and as stated earlier, I've ran the carp out'a this style mid from a '78 175 to a '84 HiPerf efi Bass, to a Bridgeport and then this 260.
I've ran over everything imaginable from stumps to an ice bag which wrapped around my lower and took out 2 cyls on the '84 and back when I was younger I only knew idle and WOT!!!
Maybe I should drill some holes and install a couple'a safety straps to save my sporty!

[FUJIMO]

...If your not building a boat to go beating across the rough ocean and circuit racing. Is there any benefit to even own an offshore midsection?...
...No...

[SUNKIST]

if you run'em real hard with twins and too much chop........

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[Forkin' Crazy]

I have regular mids, bass mids, a ridge back and a 280 offshore and a custom made lightweight offshore mid. I was just thinking about how many times i've heard of a regular mid break apart upon regular/heavy use. None really that i know of. Not including home made bass holes, drilled mid's, add a snout mids or any other home brewed slice or drilled into mids. Those are alll susceptible of failure for obvious reasons. Thats why i'm not really interested in those ones and thats why i am interested in peoples experiences with regular mids and did you ever break one.

I can tell you that you will not break an OS mid. Unless you are considered reckless abandonment!!! I haven't weighed them, but I bet my 20" OS mid weighs as much as a V6 consumer 20" with the integral trim. So then add the pump, etc. If you are racing smooth water, I would stick with the light stuff. Cory is right. They sound awesome even with the restricter plates!

[Coryc]

TBH if I were you, and this is just my opinion, I would not worry too much with the 260 vs 280 mid issue. Any smoothback will be a huge jump from a bass mid. You do get the raised snout for better idle on the 280 mid and you do get the updated stronger 4 hole mounting for the adapter plate. (I'm not sure if there's any other changes) but I don't think those are necessary to pass up a good 260 smoothback for.