Why are the Mercury 4 strokes so slow?

[Smokeyr67]

Keeping it simple, and not going down the speed versus velocity rabbit hole, I agree with you in principle.

I was pointing out that the method of measurement isn't the issue with why bass boats are slower with 4 stroke Mercs (if they actually are).

Many have asserted that it's because GPS is a more accurate measure of speed, I correctly pointed out that in reality it isn't.

I'll side with those who (in my opinion) correctly point out that if you put 3 MFD's, a TM, 36 volts worth of electricity etc etc into the same size hull, then of course the performance will suffer.

[bassfisher444]

Keeping it simple, and not going down the speed versus velocity rabbit hole, I agree with you in principle.

I was pointing out that the method of measurement isn't the issue with why bass boats are slower with 4 stroke Mercs (if they actually are).

Many have asserted that it's because GPS is a more accurate measure of speed, I correctly pointed out that in reality it isn't.

I'll side with those who (in my opinion) correctly point out that if you put 3 MFD's, a TM, 36 volts worth of electricity etc etc into the same size hull, then of course the performance will suffer.

What is a more accurate measurement of speed than GPS then? Certainly not a boat speedometer.

[Crankinh20]

I’m gonna say two strokes just develop more torque and faster.

[av]

Like Tim said it's set up always has been,

[Dennis S.]

Back in the day:
Attachment 541394

Now:
Attachment 541395

This exactly. My little 19 footer had hit 74.9 gps with me behind the wheel at one time. Now with 2-10" graphs (instead of 1-5" 'Bird), and an Ultrex instead of a Fourtrex along with the Garmin black box has impacted my top end speed to the point I am more worried about the ride than the speed. 69 is the best I see nowadays. And that is on a good tournament day.

[BOATS]

Level II coxswain school in Little Creek had Metal Shark boats for training, some had twin 2 stroke 150's and others had twin 4 stroke 150's. The 2 strokes would leave the fours in the hole but the four stroke would eventually walk by them.

[majorbanjo]

New boats are fat pigs.....overloaded with fat boys, electronics.....batteries and fishing tackle......has nothing to do with the new motors......if they were on the old boats they'd fly.....

[Kb444fishing]

Ill repower my stratos 201 soon has a 225 now going with a 250 hoping just not to loose any speed ill be happy if its the same.

[OK_BassBum]

Like Tim said it's set up always has been,

And always will be!

[GFM]

Ya, I get it. I do believe we had must less equipment on the boat 20 plus years ago. Our current equipment does (in my option) have much more wind resistance. However, I have found with lithium batteries you have less weight in the back and I have found, that hurts your speed. My buddy has the same 2023 Z20 Nitro with mostly the same equipment and tackle, same jack plate and prop. I have 4 MPH on him with regular 31 group AGM. Not sure if that is really the case, but I does make sense. Thoughts?

[hoss1908]

Ya, I get it. I do believe we had must less equipment on the boat 20 plus years ago. Our current equipment does (in my option) have much more wind resistance. However, I have found with lithium batteries you have less weight in the back and I have found, that hurts your speed. My buddy has the same 2023 Z20 Nitro with mostly the same equipment and tackle, same jack plate and prop. I have 4 MPH on him with regular 31 group AGM. Not sure if that is really the case, but I does make sense. Thoughts?

I'd say it's all in the setup if all accessories (power poles, graphs, etc) are the same. Lots of variables...same prop?, prop to pad height, weight distribution, the list goes on. If I put lithiums in the rear and lost speed, I would do what u can to shift weight from the front of the boat back to the rear. Theoretically, if im understanding correctly, holeshot would be better with weight forward, but top end would be better with weight to the rear. Based on the boats I've run anyway.

[mactlman]

Ill repower my stratos 201 soon has a 225 now going with a 250 hoping just not to loose any speed ill be happy if its the same.

will be mid to upper 70's IF set up correctly

[Klinger N Ok]

Look at the front deck of modern bassboats- they are huge compared to older models. It takes a lot of extra HP to lift that heavy bow, HP that could otherwise be used for pushing the boat forward.

[davidsa]

Look at the front deck of modern bassboats- they are huge compared to older models. It takes a lot of extra HP to lift that heavy bow, HP that could otherwise be used for pushing the boat forward.

This is my number one theory. I don't have massive graphs and I've always used gps speed so I discount these in my case. I notice that my 175hp 4s is less fuel effecient on my Phoenix 818 then my 150hp 2s was on the phoenx 618. I think the motors on fuel effeciency are very simlar so this leads me to believe I'm push much more hull width.


When I had a merc 2s 150hp optimax we had posts on the board that the motor actually put out a tested 167hp. The 175hp 2s merc was something like 187hp as memory serves. Do have have any data saying that the 4s Mercs play this game? They certainly weight a bit more.

[Bassin Bob71]

My previous boat was a '12 Z520 with a 250 Pro XS 2 stroke, no poles, and a 24V TM. Current boat has a 36V TM, 2 8' blades with a 250 Pro XS 4 stroke. Current boat has a better holeshot by alot, better midrange and is a little faster, about 1 mph, on top end with a heavier load. There is nothing I miss about the 2 stroke.

[PatriotAW4]

My previous boat was a '12 Z520 with a 250 Pro XS 2 stroke, no poles, and a 24V TM. Current boat has a 36V TM, 2 8' blades with a 250 Pro XS 4 stroke. Current boat has a better holeshot by alot, better midrange and is a little faster, about 1 mph, on top end with a heavier load. There is nothing I miss about the 2 stroke.

Rangers are exempt from this thread, they have never been quick either way.

[Bassin Bob71]

Rangers are exempt from this thread, they have never been quick either way.

Great comeback

[188Musky]

Like Tim said it's set up always has been,

Set up is the second most important thing to consider.

The first is horsepower to weight ratio.

[AZcal2021]

Hang that extra weight on a wider hull along with two power poles, 4 or more big screens, extra batteries, and a heavier trolling motor and this is what you have now.

[ChuckTR21]

I have a BCB Eyra. Had a 250 PXS 2 stroke originally and now have a 4 stroke. Last time I fished back in November, ran 77 and change with live wells full and 3/4 tank of gas. The two stroke wasn’t really any faster so I can’t say the 4 stroke is slow or slower.