My new build for the Ford 408

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SWAMPHUNTER45
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Re: My new build for the Ford 408

Post by SWAMPHUNTER45 »

When your attempting to get a power gain in the straight drive configuration the dollars you need to spend for gain make a gear drive look cheap.

I know this because I was there and lived it firsthand.

Some things to try:
So the addition of the 2 inch carb spacer may add 5-10 pounds of torque. Making it from wood is genius and will also serve to prevent a heat transfer. There are commercial plates of wood used to isolate heat from the Carberator. Your craftsmanship looks great.

Another thing to consider is your prop hub adapter. Are you running a 2 inch or 4 inch? We found a slight gain in push by going out to 6 inches and old timers have used 8 inch spacers before but adding length creates added stress. The 6 inch spacer aided in airflow to the prop by setting it back from the engine.


Another thing to try is a air intake system much like a ram horn style. We saw a slight gain from that. Mine was a dual feed aimed to use the airstream to sort of Ram Air the flow. Think I used parts from Spectre to assemble.

Back in the day before I sucked it up and went to the gear drive we tried everything plus nitrous. We considered a supercharger and spoke with the techs at Vortech. In the end because of the 3,000 rpm max they felt it was not the best use of the money required to purchase and install.

I’m sure that 408 on a 2:12 or maybe even a 2:38 with a 3 blade JX would be the perfect pairing.



That engine you have is a great engine so strongly consider a gear drive modification. Talking from experience you will never regret that expenditure.
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Re: My new build for the Ford 408

Post by Heavy »

Daniel here is a my 557 dyno sheet for the second pull. While these were not the final numbers ( I cant find the others) it still appears that you will need to much RPM's to make this engine work well in a DD application. What I do know is the final numbers were above 700lbs TQ and HP and it pushes really good with a 3 blade R set at about 2 1/2 and a 2:38 Ox Box behind it. Hope this attaches correctly.
Scan 2.pdf
(312.39 KiB) Downloaded 46 times
14' Jimmy White /557BB Ford Motor :florida: :rebel:
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OneBFC
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Re: My new build for the Ford 408

Post by OneBFC »

https://www.summitracing.com/parts/tfs-n4150

Just saying, $500 a lot less than any other options for power that you don't need full time.

The 557 would be cool, no doubt.

You will get there one way or another!
-Russ
-----------------------------------
The only thing stopping you is FEAR
400+hp Ecotec, 12x7.6 DBDO, 80" 3B Maximus, 2.3 OX,85+mph, water = purely optional
Life begins at 2 BAR, Just a good ole boy
hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

Heavy how big are the heads and the cam? Through all my research small heads and the right cam make all the difference. Nobody ever builds for low end power, which boggles my mind since trucks that pull trailers rarely see over 4000 rpms. It seems everyone is more concerned with making them scream! Cadillac engines seem to be the go to big cubic inch DD engines. From what Swamp and Buddy branch say they're not gearbox friendly and takes piles of money to use a box with them. So what is so damn different about a 385 series Ford? Stock block .080 over yields 4.440 bore combined with a 4.500 stroke makes 557. To me the key is keeping the intake runners small and purpose ground cam. No offense to anyone on this forum but you can take any turd and bolt a gearbox to it and climb hills. Junkyard LS engines and Ebay turbo kits can produce mega numbers in street cars, but for how long? Innovation never succeeds by not venturing out of bounds. I don't need a rocketship just give me a tractor that will last forever!
Last edited by hdsadey on Wed May 05, 2021 7:52 pm, edited 1 time in total.
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hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

BFC how much horsepower does that Ecotec make? Watched you YouTube video of the thrust test. Made over 1100 lbs. of thrust? How much thrust can be had out of a large blade like your swinging? If I'm 1840 lbs. on a 12x8, what do some of these big fancy 14' and up rigs weigh that can run dry? What kind of thrust are they making? Sorry for so many questions just trying to wrap my head around some of this!
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OneBFC
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Re: My new build for the Ford 408

Post by OneBFC »

Well, the ecoturd makes somewhere north of 400 and likely under 450. We make 14xxlbs of thrust with it and its been good to me. Others have not been as successful, but still others have. Its, unfortunately, a difficult engine to get setup and running for anyone that isn't comfortable with modern engine control systems.

Not a trivial task to tackle and I do not recommend anyone try it these days unless you have a lot of patience.

My boat weighs in 14xx lbs (yes, about same as the thrust). 14ft deck over boats come in anywhere between 1600 and 2000 lbs quite commonly and usually run very well with a healthy LS in the 500 to 600hp range + gear box.

You will never make enough power at 3000 and below without using a power adder like forced induction or nitrous (still forced induction).

Maybe you can get a 557 to produce 400hp at 3000. Odds are against you, but perhaps doable. Note that it takes am Aircraft engine in the 720ci range to make 400hp in that same rpm range. Sure, maybe some 540s that are pretty modified might get close to that too.

DD power is a lot more difficult and expensive than RPM. On top of that, its less reliable too since cylinder pressures are a lot higher at 400hp at 3000 than they are at 400hp at 5500 rpm.

If you are on a budget, I still think the Nitrous route is very viable. As long as you don't need to run at high power too often, its nearly perfect.
-Russ
-----------------------------------
The only thing stopping you is FEAR
400+hp Ecotec, 12x7.6 DBDO, 80" 3B Maximus, 2.3 OX,85+mph, water = purely optional
Life begins at 2 BAR, Just a good ole boy
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Slidin Gator
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Re: My new build for the Ford 408

Post by Slidin Gator »

HD,

Don't throw a log on the back for sure, 650 ft-lbs and dropping at 4,000 ain't the DD solution, Heavy's name be good. I talked to Mr. Branch last year. He offered a stroked light weight block that would weigh 500 lbs and make 600 ft-lbs all day long, turned to 4,800 ish max. My 480 lb injected 540 makes 600 ft-lbs all day long. It's all about prop torque, you gotta gear it to get much more than 600 at the prop. Gear box is less weight vs. a big block adder.

Otherwise, follow Kwan's lead.
kwanjangnihm wrote:
Wed May 05, 2021 7:02 am
HD could you test a smaller diameter prop that would get you up in the 35-3600 rpm range, making 360hp & 526tq as a test. (see info below) :scratch:
Davie GSO480 wrote:
Tue Jun 25, 2019 5:25 pm
Hi all.....been a while sense ive been on this board.

I also had Dave build me a DD LS.
The motor is a LS3 block
EFI holley system
430 CI, Chevrolet cnc heads.

Dave (Waterthunder) has a thrust tester, it will measure thrust output.....it makes 1100 pounds + At 3600 with the Alpha 66
Most straight valve 0-540 make 940 =/-, angle valve 1000 +if its 10-to 1
I was at the last Thruman outting......Black full deck,,,,,,,,Midnight Rider..

The prop is a 3 blade Sensenich Alpha,,,,,,it makes thrust up to 3600......at 66 inches
Right now Im running it at 68 Inches and turning it 3200.
It will run with most 0-540 boats......
Ill post up a couple pictures and race videos...
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.
Heavy
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Re: My new build for the Ford 408

Post by Heavy »

HD, my heads and cam was definitely bigger or different than what you would need in a direct drive application. My only purpose for posting was to say that just because you increase the CI to 557 it still may not do what you are trying to achieve. I do agree that a purpose built 385 series will put you in a better spot than the 408 you currently have. Like you stated cam and heads are everything when you know what you are trying to achieve. I just picked up a 460 from a industrial application that is building max torque at 1600 rpms and max HP at 2300 rpms so it is defiantly possible to build these motors for the low end. Good luck on what you decide but IMO you have been working for some time on this and you should finish it up take it for a ride and relax a little while you decide which way to go. Maybe take ONEBFC advise on the power adder for $500 before you pull the trigger on scrapping the idea of using your motor.
14' Jimmy White /557BB Ford Motor :florida: :rebel:
Heavy
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Re: My new build for the Ford 408

Post by Heavy »

HD, were you able to get it on the water to see how it performed yet or decided what your next plan of attack might be.
14' Jimmy White /557BB Ford Motor :florida: :rebel:
hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

In about 2 hours I'm planning to splash it for the first time. Hopefully all goes well.
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Heavy
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Re: My new build for the Ford 408

Post by Heavy »

Good luck and post the update when you get a chance.
14' Jimmy White /557BB Ford Motor :florida: :rebel:
hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

Well it didn't sink or roll over! Will cruise deep water at 2100. Feels awfully heavy, go figure 1840 f@$in lbs. Doesn't have the snap it did with the 72" setup. Has a hop which I believe is either engine angle or rigging too far back. Didn't try to stop and start on dry ground since I didn't have any help if I couldn't get it moving. Air ride system really takes some of the jolt out of the ride actually really comfortable. I tried a new hydraulic steering setup that I designed, it works but it's a slow reacting system. Need to change the bore ratios to see if I can improve the reaction time. IT FELT GOOD TO FINALLY GET OUT ON THE RIVER AGAIN AFTER ALMOST 2 YEARS SO WITH RESPECT TO THAT IT WAS AN ABSOLUTE SUCCESS!!!!!
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keys2pines
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Re: My new build for the Ford 408

Post by keys2pines »

Looks awesome man! I'm almost two years into my hull rebuild also, sucks big time not being out there.
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hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

Thank you sir. Been a long road to here. Tried some different things. Overall I'm happy with the end result. Time to have fun for a while and not worry about the details.
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kwanjangnihm
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Re: My new build for the Ford 408

Post by kwanjangnihm »

HD the new boat looks great man!
I too am 2+ years into my build, so hopefully I’ll see you guys on the river or marsh soon.
Slide safe!!
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.
hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

Just out of curiosity how many inches does a gearbox add to the engine from the prop?
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kwanjangnihm
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Re: My new build for the Ford 408

Post by kwanjangnihm »

12”
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.
hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

Just so happens that when I built the rigging the mounting in the stringers, the bolts are 12" on center. So if I was to get a gearbox, I can move the rigging forward to accommodate the setup. Minimal fab would be required.
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SWAMPHUNTER45
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Re: My new build for the Ford 408

Post by SWAMPHUNTER45 »

Been there / done that and love the results.

BluBayou and I built my rigging for the DD 514 Caddy.

It ran dry but not as good as I had hoped for even with a power adder. He knew I was looking for more and had acquired a used gear drive on the cheap. Everyone from Mr. Branch, TerryF, Dagwood to OneEye offered up advice and in the end things fell in place to go to a gear drive.

While I was away on family business Blu who is like a brother from another mother de-rigged my boat and cut my rigging in half. He then re-fabricated it to a gear drive set up. My rigging base was square tube so he sleeved it internally and then welded it back at the base and put the tabs to cover any weld seam.

I would think if you can get a good welder and put enough thought into the design you may be able to do the same.

Trust me you will really be happy with the end result.

I know everyone has a budget and some are bigger than others but having a boat that performs well and making yourself happy is priceless.

Gear drive that bitch !
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Re: My new build for the Ford 408

Post by hdsadey »

Well since I bent and welded all the rigging myself, I guess moving it forward a foot to accommodate the box is no big deal LOL. Would have to reengineer the front and rear mounts to drop the engine so to keep the center of the prop where it is. Input shaft to output shaft is what? 10 inches?
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JLP3314
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Re: My new build for the Ford 408

Post by JLP3314 »

A sharp-yet simple (compared to many) boat/running a Ford to boot.
Congrats on keeping the blue oval alive.
Don't waste your time-its the only thing you can't get back, (Cntry141IQ/John had another thousand of these before he went sliding into the sky). :-(
Heavy
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Re: My new build for the Ford 408

Post by Heavy »

Congrats on a successful day. A good day on the water makes you realize why we go through all the BS to build and rig these things. That is a great looking boat. :thumbleft:
14' Jimmy White /557BB Ford Motor :florida: :rebel:
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Re: My new build for the Ford 408

Post by One Eyed Gator »

Nice looking ride. You will find the gearbox to be a wonderful thing.

Yep been there on the DD thing.

Ran a Caddy for 10years. Got a 2:1 precision for next to nothing got it set-up of my caddy. Then built a boat for a buddy with a 5.3 out of a truck. He wanted a lighter motor and found his a l33 5.3. He gave me the truck 5.3 ran it with the 2:1 Then got a deal on a low hour 2.68 stinger. Found a deal on a 6.0 added a ASA cam some 706 heads (for higher compression) put the 2.00 valves in it. With low hours on the stinger had bearing issues. bought a 2.55:1 oxbox. Currently the motor is carbed with a MSD box, but I have come across a Holley HP terminator (not terminator X) have the TBSS intake Holley TB and tbss injectors. Almost done with fishing this season and will switch over shortly to EFI

Finally boat does everything I need it to plus.

But found a deal on a .030 6.0 so building a 370 ls.

Never seems to stop LOL

But then again I love to tinker on different projects.
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keys2pines
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Re: My new build for the Ford 408

Post by keys2pines »

If you decide to go gear box I’ll trade you my 4 barrel Fitech for your 2 barrel.
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hdsadey
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Re: My new build for the Ford 408

Post by hdsadey »

That might just be an option sir. I sold the 4 barrel I had before and quite certain I will need another one.
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