Mercury 300 V8 vs Mercury 400 L6 | In depth comparison and real world testing

n this video, Chris Bazor takes us on two 2020 Fountain 38 CC's. One powered by Triple Mercury 300 V8's and the other powered by Triple Mercury 400 L6's. We take the boats out for performance testing in a real-world environment and you can see the results first hand! Enjoy the video! Both of these boats are available at Grander Marine. Call us and check out our website!
www.grandermarine.com

[@EESDesignLLC]

Fantastic information, Thank you!!!! Looking forward to seeing this same type of video for the Mercury Racing 400R's and the new V8 450R's PLEASE DO THIS!!!! Thank you!!

[@Jassman3536]

Good video Chris. Very informative and straight forward.

[@Prototheria]

After recently returning to boats from a 30 year hiatus, all I can say is holy shit, both those boats are mind blowing.

[@brentstenslokken9258]

Great review!!! Do more boats like this!!

[@ekbusdriver]

Awesome vid!! Thank you. Have been dying to see the new V8s would perform. Impressive. Would have been nice to show the fuel flow on the 400s.

[@EdD-ym6le]

Great vid Chris . That's a great Hull .

[@drmarkadufrene8153]

That was fantastic… thanks for doing this. Insightful….

[@7287287]

Interesting thing to look at was the active trim on both test.

[@abdullaalkhoori3812]

amazing and very helpful video,, thank you guys

[@lizmigueli]

excellent information tank you very much

[@seabelle35sc98]

Great video, thanks

[@darrylclaxton7473]

This place is in orange Beach Al. I looked at these boats last summer.....serious redicoulous boats. Love it.

[@andrewcapone3345]

Glad to see someone doing these live on water comparisons. Wish they were identical boat option setups but still good! The 400's were on a heavier boat with 70 gal more fuel (1 gal gas = 6.3 lbs, so 441 lbs more in fuel) onboard and overall 300 lbs heavier just in engines compared to the 300's. Overall the 300's had more torque and less weight to push! I'm guessing identical optioned boats with same load for fishing you'll see a bigger difference in numbers due to the 400's being at an overall weight disadvantage in this test!? I would probably go V8's...you cannot always go top end...because it's not always flat..especially here in the Atlantic off NJ! Keep up the good work on these tests.

[@benniewolfe3379]

During this whole video all I could think about was how interested I would be to see some performance #'s from that 34cc with those triple 300 V8's sitting beside the 38cc.

[@chrislane5670]

Chris, glad your still running Fountain, think i found a quad boat for you in CT back in 2009 ~ when i bought mine... Im digging the new NX

[@GranderMarineElberta]

Thank you Chris,. Correct sir, that was out 2007 38 open with quad 300 opti, that was a sweet one. I hope life is treating you well.

[@chrislane5670]

@@GranderMarineElberta I ended up with a 58 Ocean SS ~ but been testing wife lately as i really miss the fountain!! This video is incredible the fuel efficiency ~ amazing... I think i love that 38 Open Bow.... Could be my next one...

[@WhalerGA]

Around 1:40 you say you are trying to gear them equivalently but I'm not sure you did. 28P w/1.85 gear on the 300 vs 23P w/1.75 gear on the 400 gives the 400 a 15% gearing advantage. I realize there are differences in the true effective pitches of the different prop models (Bravo I FS vs Revolution 4). Are you saying that the 23P Revolution 4's run more like 26-27P Bravo I FS's). And why run 4-blade on one boat and 3-blade on the other. That introduces a major variable between the two. Around 11:40 it sounds as if you were trying to prop the boats to get them both 2-300rpms below their rev limiters @ WOT. That would make sense but it's not the same as gearing them equivalently. But thanks for the comparison. It has provided great insight.

[@Respecet1981]

Great job

[@RomainSandt]

gorgeous boats. God those V8s sound good. Happy to seen the L6 are still great. Just wonder what twin 450s would do vs triple 300s.

[@JamesBrown-ux9ds]

I liked the sound of the sixes more. And, besides the potential sound likes or dislikes, there seems still plenty good reason why BMW car holds firm on those strait sixes now for such a long time.

[@miketee2444]

I will take a round of either of them. I'm just wondering if the 600 is going to 750 or 8 when Merc starts force feeding it a bunch of air and fuel. I think they made a good call on the V 12. Seems giant outboard hulls are selling fast and 4 or 5 motors starts to reach a point of too much going on. Most boats can cut back to two or three big boys and be better off. Plus I never could get past how loud the seven Marines were. Merc does a dam good job in that category to.

[@marcoticci]

Good job 👍

[@jiggingjerks]

Insanely impressive. Well done Chris!

[@lochlannelson1901]

Sorry to be offtopic but does anyone know a way to get back into an Instagram account? I somehow lost my login password. I would appreciate any tips you can give me.

[@omarkason9236]

@Lochlan Nelson Instablaster ;)

[@lochlannelson1901]

@Omar Kason i really appreciate your reply. I got to the site on google and im trying it out atm. Seems to take quite some time so I will get back to you later when my account password hopefully is recovered.

[@lochlannelson1901]

@Omar Kason It did the trick and I finally got access to my account again. Im so happy:D Thank you so much, you saved my ass :D

[@omarkason9236]

@Lochlan Nelson You are welcome xD

[@shingnosis]

Very, very good video but I'm not sure I agree with your conclusion that the 400's were more fuel efficient at high cruise. I looked at the video and wrote down some numbers and I got roughly: 3x300@50mph: 1.55mpg 3x300@60mph: 1.25mpg 3x400@50mph: 1.44mpg 3x400@60mph: 1.21mpg So looking at the video I would say that (accounting for some margin of error) the 300's are more fuel efficient, or at least as fuel efficient, across the board. This also makes sense from a mechanical and theoretical point of view since a compressor fed engine should not be more fuel efficient at high revs than a naturally aspirated one. The benefit of a compressor fed engine is mostly in the low to mid-range, for higher revs they're not a very efficient design. Also a note about that mid-range "torque" you're feeling with the 300's. When you nudge the throttle the engine actually gives you more throttle and power than you ask for. This has to do with the Mercury ASC system which is "rpm seeking" rather than "load seeking". So when you move the throttle you're actually asking for a certain rpm and the engine management gives you quite a bit of power to get to that rpm. The effect is similar to opening the throttle more on the 400's and then dialing it back. Other than that excellent video, just the fact that you mention things like prop pitch, gear ratios, boat weight etc shows that you're a pro and know your stuff.

[@deven6518]

Didn't read much except the compressor part and I'd have to disagree. A compressor fed engine is usually more fuel efficient than naturally aspirated. Gas doesn't give you power, the air does. How much fuel you need to do so is down to your compression and air fuel ratio. But generally fuel for fuel, a compressor engine gives more power therefore you can have better fuel efficiency on them . Turbos and superchargers are mostly used for that purpose specifically. You can increase power quite a bit from compressed air intake before you need to increase fuel intake and as such the 400s would burn only slightly more fuel at Max load. But the thing is with more power, an engine will face less load and runs more efficienty. So yes, more power often means less fuel burnt within a certain margin. Like sort of the way a 2l car engine at Max revs may be getting 9 mpg to tow a pickup truck, but the big 5l V8 in that pickup truck towing that car may get 14mpg. It's the same weight, just less load on the engine because it has more power.

[@fullsendmarinedarwin7244]

I'm not sure if I'm a huge fan of the RPM seek (instead of plain throttle demand) ... it makes the engine surge at WOT ... not by much but get very inconsistent results at WOT even a small change in JP, Trim, Chop can make a 5-8kts difference in WOT speed ... at least with the 200hp v8

[@chippyjohn1]

@@deven6518 A compressor does give you more power, but you have to run it richer also to keep knock down.

[@deven6518]

@@chippyjohn1 not necessarily. Per gram of fuel, a compressor gives more power. You can get more power at the same fuel, alot more power fir more fuel, or the same power for less fuel. It all depends on what you want. If the goal is a large power increase, then obviously one would need to increase fuel. Generally you avoid knock and misfires/ early detonation by adjusting timing and compression ratios. Only throwing more fuel at it will rarely solve your issue. More power though, still means the ability to achieve the same performance at less strain, and that power can be achieved, within reason, on the same fuel and some turning.

[@chippyjohn1]

@@deven6518 That is more relevant to diesels. A diesel can run leaner, but petrol will have issues when running lean. These engines being petrol port injection, under full load a forced induction engine will have to run richer. The average factory petrol engine runs no more than 50kpa of boost, after this point the economy returns are significantly reduced. A forced induction engine is better in volumetric efficiency, but not fuel efficiency. So you can make more power with less engine weight/size, this is important for keeping an outboards weight down and any engine and in turn the weight saving will bring back more economy, but the BSFC will be higher. I have done a lot of research into this, I am not a novice. Theoretically, you could run a forced induction engine with a better BSFC, however it is difficult and so many factors to consider, so for the average mass produced novice owned engine it is not the case.

[@MichaelKallelisOn2Wheels]

Looks like it was a fun day riding those two boats. For this old guy, 70mph on the water is nuts. So plenty of power, too much for me. Twins will serve me just fine and comfortable 30-40 mph.

[@stevefowler2112]

39 Fountains with triple screws...some nice fishin boats there. I am going to look at a 2018 Key West 239 FS cc tomorrow, my big draw is she has the Verado V8 300 with only 80 hrs....the boat only weighs 2,700 lbs without the engine so approx. 3,300 with a the 300 Verado, should run nice.

[@robertsouthrey3480]

very cool thanks

[@zachfrye-lofley184]

Any idea on speed of this is y’all did quad 450s? I know you have the quad 400s that hit 91.9

[@ayrtondeandrade5607]

How does the 38 perform offshore does she pound or cut through 4-6 footers at like 35 mph

[@richardrose2457]

I like the 300 Thanks

[@roncaptain9527]

Thank you very much for your comparison test ... I am in the market for 300 hp Mercury's... I am repowering a Boston Whaler 27 FC ... We use our boats for towing and Salvage work ... We tow vessels from Key West to South Padre Island Texas ... What would you recommend? Electric shift and throttle ?..Or Cable shift and throttle ? Very Sincerely, Captain Ron, Naples FL

[@robgrundwald]

87 octane in the 300 over 91 octane in the 400 is what made me choose the V8 in my next boat, something that should be mentioned.

[@mcplutt]

V8 300 is a no-brainer in most cases.

[@jeremyjmailloux]

Not to mention the cheaper maintenance costs. The 400 Verado needs the serpentine belt changed every 100 hours, the expensive 25w50 engine oil, just more stuff to go wrong. That's a lot of power out of a 2.6L i6 compared to a 4.6L v8 so your sacrificing some durability. I've had verados in the shop for low power and it was a blown charge pipe clamp. Neither are easy to work on however.

[@stevefowler2112]

I thought the recommended fuel for the 300 V8 Verado was 91 octane too?

[@jeremyjmailloux]

@@stevefowler2112 nope 87 octane with upto 10% ethanol in all 300hp V8's is the recommended minimum. The I6 Verados need 91 because of the supercharger.

[@mcplutt]

@@jeremyjmailloux Not to mention the V8 sound :-)

[@robhobbs9980]

What numbers do they run with more than vapor in the fuel tank? Realistically full of fuel, ice, tackle, bodies?

[@JWnFlorida]

Love the testing.. but you could run to the bahamas though.. do some fun stuff bro, you rock!

[@angryseagull3898]

We got a 250 verado V8 and when we got it the boat was out of the water and on the sports setting and when they started up i jumped it was so loud

[@timshull59]

Looking at 22ft pontoon with the L 200, just wanting to know if it's a decent power plant..

[@smashley61587]

What some people don’t understand is that smaller motor has to work harder which = more fuel consumption. The bigger motors don’t have to work so hard to push the boat = less fuel consumption

[@jaarryifleshblood315]

I’m suprised how efficient the v8 is. I don’t think I see any vids on how efficient the Mercury’s are.

[@FLseahawk]

Boston Whaler has spec sheets for the 350 OR with triple V8s and triple 400 L6s. At WOT the 400s burn 38 gph each for 112 gph and for the above fountain that pushed the speed t over 70. At WOT the above Fountain would be closer to .6 mpg, almost half of what the Vessel View was indicating. Using the same data from Whaler and personal experience the Merc V8 300s only consume 24.5 gph WOT each, for a total of 73 gph. So two top speeds near 70, the V8 annihilates the 400 in hole shot and mid range and the V8s burn 39 GPH LESS at WOT. It makes sense, a V8 is more efficient; more pistons doing work on a given rotation and the larger displacement will yield more torque. The V8 300s can be had for somewhere north of $20k.

[@offshoreapparelsales3364]

Why bravo FS on the v8’s and not rev4? Or rev4 xp?

[@guntman6084]

Are the v8s much louder? I like as quiet as possible.

[@bigguy1403]

What's the difference between the l6D 400 veradovrs the l6M 400 verado

[@ivanhall9638]

Why didn't you compare both 300 rated engines?

[@cmcconn100]

Thanks for the informative comparison. I'm looking at a totally different class of boats but considering the Verado V-8. It certainly sounds better. I'm looking at a 24-foot pontoon boat, probably with around 250 horsepower. One guy is pushing Mercury, the other is pushing Honda. I'd like to throw Yamaha and Suzuki into the mix. Any thoughts? This is going to be an all-around use boat, lot of cruising, some fishing, watersports. I care about bang for the buck, reliability, and resale. The MErcury looks great and sounds great, but in the end, that won't make the decision for me.

[@sdvten]

Suzuki is the best bang for the buck outboard available IMO, very reliable at a very good price. I'd take a Honda, Yamaha or Suzuki over a Mercury myself.

[@melrose9252]

Chris M < Go with Mercury then Yamaha if you can’t get a Merc.

[@ajkalwaysneedsmoreinfo.576]

Curious what do those boats cost?

[@flyingfox10001]

nice

[@stephenskierski5633]

Great test! 300's are the better choice... 1.7 mpg at 50 mph and only 8 mph slower on the top end.

[@starrsnowden6103]

www.bostonwhaler.com/family-overview/conquest-boat-models/325-conquest/ test data look at 5000 rpm range for MPG 350 hp inline 6 better and no where near rpm limit V-8 almost to rev limit on lighter boat.... Merc is pushing new look down our throats.

[@benjigans1419]

@@starrsnowden6103 Yeah, id say. I just repowered my 05 305 conquest whaler. It had twin 2005 Gen I L6 250 verados and I just bought a pair of brand new 2020 350 L6 verados. These motors are the most powerful outboards I've ever seen (yes, even better than the 350 Yammies or 350 Suzukis), incredibly fuel efficient, and more. I went from 29 mph at WOT with my 250 verados and now I do 40 at WOT and I go 29 at 3900 rpms on an average day with an average load. The V8 Verados don't seem like real verados, they're more of a pro-xs with verado features

[@gwagb27]

Do 3 450r’s!

[@Semperfi2011]

Number one motor I’ve seen being cranked on more than once at the boat launch/marina- Mercury. While me and my Yamahas are already on the grounds

[@starrsnowden6103]

obvious reply is get a life, mere owners got laid the night before.

[@powerboatguy2308]

More efficient than the V8 4 liter Johnsons two strokes I ran on my boat back in the old days.

[@elibnem4126]

Thanks for reminding me ill never own such amazing boats. Cool vid though

[@25Coronado]

What is the cost difference?

[@raykrv6a]

What's the price of each boat and price of the 400 vs 300? BTW, really nice video.

[@KMT15]

The 300 and 400 are about the same price

[@jonathanmack8487]

You should have tried low planing speed to test torque not just the high end speed

[@mcplutt]

Delay from the supercharger? There is no delay from the supercharger.

[@CoastieRob]

There is on these

[@inblue3141]

V8 n/a vs L6 turbocharger 이겠죠? 당연 터보차져가 더 킅 출력을 내겠죠. 초반 가속력도 좋고

[@jamesmerkel9442]

the 300s r not enough high speed for ferrying but most ppl normal boating will love them.

[@rodcouey2617]

Not sure you can call it real wold when you are spinning a different prop and 100 gal less fuel. I get the different pitch but they should be the same prop. from one style to the next can change everything. hell, I have ran the same make model and pitch prop and they are a tad different. and 700 lb of fuel is huge. when it comes to efficiency everything matters..... I got 6 mph out of 1/4 higher X . I like that you took the time and it will give a general ball park but I could get 5 mph min out of either boat in an hour so dialing in.

[@jasoncooperpcola]

Yall changed the props out on the 400 L6 Verados to even out the gear ratio. Is that how yall would prop that boat out for optimum performance?

[@kcolmeh62]

Good question. Were the 400s hitting up against the limiter? The sensible comparison is to prop both boats as you would so that WOT would be in the range it should be. I think you said the 200-300 below the rev limiter? The other thing I noticed is that the speed was still changing when you were noting economy numbers. If the boat is slowing as you record an eco number it will be skewed to the high side and of course the reverse is true if the boat is accelerating through a number. To get a more true eco number at some of those speeds, you need to let the boat settle into that speed a bit longer. On the whole, great video. Very much enjoyed watching the collection of data.

[@dezray5547]

Triple V12s on the 38

[@marioncobaretti2280]

I like the top speed , l6,s my choice even though I'm a v8 person

[@drewp25831]

ill take 2 of the new V12's... cha-ching

[@kenfung664]

Trip 300s hitting 70 isnt bad at all

[@vinriffic]

Shouldn’t it be an I6?

[@davidfrank6666]

u would think. good "?".

[@StockIndexFuturesALGO]

Careful with that trim, she was looking a tad squirrely @78mph

[@edt.9218]

could have equalized the weights....

[@shawntandy4326]

think i will drop down there and buy both lol........one engine cost more than my house!

[@stephenlane2826]

Good vid but an 800 to 900 lb difference in weight totally leaves alot open for interpretation.

[@Deepimpactocean]

Can anyone confirm that the new 300 Verados are any more reliable than the supercharged 300 Verados?

[@321thach]

S Works if you a want reliable engine get a Yamaha

[@slit4659]

I don't know why they still put the ROPE PULL STARTING ROPE on these big Motors.....I guess it's just a Safety thing.

[@riverakers]

I would think these engines would have an incremental rpm control.

[@rsdna9698]

They do, but only for trolling up to 1000 rpm's.

[@marshmellow3110]

V8’s

[@jamesmerkel9442]

9:12 last code & 12:22 this video code roach on left hand. comment number 87 showing.

[@dingo397]

Man you went through all that explanation on fuel economy...lmao....Bottom line they were both out of this world and they Purrr....lol

[@colbybud]

The good thing is if hit a deadhead or log you would simply skip over it. you would essentially be flying lol.

[@thedeanofbacon5270]

If you're looking at 40 feet and 3 engines, it's all gravy anyway.

[@jamesmerkel9442]

The V12s save me needing 5th motor 3,or 4 engines per mini is enough, but if running 450s will need 5th motor for sure.

[@jamesmerkel9442]

I meant 400s will need 5th motor for sure, VS 450s or V12>600s. Either can get by w/450s or will hve to go 600s not sure what way better 5 engine at 450s or 4 V12 at 600.

[@manuelfuertes5875]

400

[@THESHADOW97139]

Ok.....now,same with 400 V10 ....3 boat

[@Kadetttreter78]

There’s nothing over a V8 !

[@cornfilledscreamer614]

The 400's would cost just about $18k more than the 300's. You can buy a lot of gas, beer & bait with that...

[@jamesmerkel9442]

HP 2250 is better code then 2400 but hve to add up all the mini's upfront not as big a deal cost of operation fuel burn & long term high use & heavy loading. 6 mini's 8mini's or 10 mini's at 2250 or 2400= V12 bad coding across the math. Codes busted 5 engines per mini as well no go. Must b a diff engine option not 450, not 400, & not 600s, is there another option of engine coding I can try that is bullet proof.

[@jamesmerkel9442]

700lbs vs 600lbs is more than man can pick up and beetle bug work on so not a factor, just easy of design to work on is a factor.

[@honda8720]

I think the v8 has more torque

[@starrsnowden6103]

no shit but 800 less rpm.... do you want to run hundreds of hours 200 rpm under redline or 1000 rpm under redline?

[@marioncobaretti2280]

L6 revs higher

[@gregoryh4601]

Sir there a little mistake you made V6 = 1200 hp. Your V8 = 900 hp come on dude, add one more to the V8 to be FAIR.

[@4to20ma6]

Ill never be able to afford to fuel them up. Bye

[@aaron-fauth]

See ya

[@KMT15]

Later peasant.

[@colintraveller]

Jazzed up speedboat .. IMO . It's not something you would buy if you were wanting to stay out overnight .. And if you live in a colder climate ypu would want something that offers better protection from the elements . More suited to warmer climates . I can garuntee I will not see one of those scooting about the River Clyde .

[@jockeolzzon1222]

8 mph trolling speed? lmfao

[@marioncobaretti2280]

v-8,s sound better but 9 mph slower

[@bmunson76]

I hate that look of those 300s though. They're ugly.

[@timbrewer9066]

Just so everyone knows, the Mercury 300 is not a V8.

[@sheepdog1102]

Yes it is! The new V8 300 4.6 liter. And also make a 450 V8 4.6 liter supercharged .

[@starrsnowden6103]

yeah um they needed to catch up to the 700 HP v8 so mad a new standard V-8 and now the 425 to 450 are the supercharged v8... yamaha has the 475HP it looks like you took a nissan hood and flipped it vertical...

[@shingnosis]

Very, very good video but I'm not sure I agree with your conclusion that the 400's were more fuel efficient at high cruise. I looked at the video and wrote down some numbers and I got roughly: 3x300@50mph: 1.55mpg 3x300@60mph: 1.25mpg 3x400@50mph: 1.44mpg 3x400@60mph: 1.21mpg So looking at the video I would say that (accounting for some margin of error) the 300's are more fuel efficient, or at least as fuel efficient, across the board. This also makes sense from a mechanical and theoretical point of view since a compressor fed engine should not be more fuel efficient at high revs than a naturally aspirated one. The benefit of a compressor fed engine is mostly in the low to mid-range, for higher revs they're not a very efficient design. Also a note about that mid-range "torque" you're feeling with the 300's. When you nudge the throttle the engine actually gives you more throttle and power than you ask for. This has to do with the Mercury ASC system which is "rpm seeking" rather than "load seeking". So when you move the throttle you're actually asking for a certain rpm and the engine management gives you quite a bit of power to get to that rpm. The effect is similar to opening the throttle more on the 400's and then dialing it back. Other than that excellent video, just the fact that you mention things like prop pitch, gear ratios, boat weight etc shows that you're a pro and know your stuff.

[@shingnosis]

Very, very good video but I'm not sure I agree with your conclusion that the 400's were more fuel efficient at high cruise. I looked at the video and wrote down some numbers and I got roughly: 3x300@50mph: 1.55mpg 3x300@60mph: 1.25mpg 3x400@50mph: 1.44mpg 3x400@60mph: 1.21mpg So looking at the video I would say that (accounting for some margin of error) the 300's are more fuel efficient, or at least as fuel efficient, across the board. This also makes sense from a mechanical and theoretical point of view since a compressor fed engine should not be more fuel efficient at high revs than a naturally aspirated one. The benefit of a compressor fed engine is mostly in the low to mid-range, for higher revs they're not a very efficient design. Also a note about that mid-range "torque" you're feeling with the 300's. When you nudge the throttle the engine actually gives you more throttle and power than you ask for. This has to do with the Mercury ASC system which is "rpm seeking" rather than "load seeking". So when you move the throttle you're actually asking for a certain rpm and the engine management gives you quite a bit of power to get to that rpm. The effect is similar to opening the throttle more on the 400's and then dialing it back. Other than that excellent video, just the fact that you mention things like prop pitch, gear ratios, boat weight etc shows that you're a pro and know your stuff.

[@boatdr.t5737]

Yea ,yea yea we get it !! Try again maybe someone will give a shit !!!

[@starrsnowden6103]

www.bostonwhaler.com/family-overview/conquest-boat-models/325-conquest/ look at these numbers from same boats except the test weight and prop size... supercharged had better MPH at higher cruise.