Engine choice help

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NotAGuide
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Engine choice help

Post by NotAGuide »

Looking for a little advise on what others think would be a good replacement route for my old tired 454. After reading the "Horsepower, Prop, and Dyno" thread in the Tech forum, I'm scratching my head on what direction to go.

My current setup is an older 18' aluminum Panther/Dixie style hull with all aluminum rigging. The engine is a '73up 454 with cast iron heads and Holley 750 single pump carb on a Edel-performer intake. Engine looks to be mostly stock and probably is straight out of a old truck. Its pushing a 80" stumppuller (12"blade) with 2:1 belt reduction. As for performance, the boat jumps up suprisingly well but only runs around 30mph at 4000rpm's. WOT is around 4500 by myself and 4300 loaded. It will run dry but wont start off on dry ground. Its an old beat war wagon but suits me well for hunting and hauling a bunch of big dudes in the salt marsh.

What I'm considering is having a local shop build me a 496 (stoker) from my existing block. I've got access to a set of aluminum rectangular port heads for a decent price. It will need a new intake and carb as well. Money is always an object but still would like more power and hopefully have increased performance. I know a lot of people are moving towards more prop and more reduction, but I'd like to change as little as possible. I just dont want to spend good money after bad.

What kind of torque/hp numbers should I expect and what would be best suited for my setup? Would aluminum heads be worth the extra cost with performance gains and weight reduction? Also, is a Ch.3 belt drive able to handle more than 400hp thats stamped on the housing? Thanks in advance for your help!
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yobee
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Re: Engine choice help

Post by yobee »

I think freshening up your big block would be the way to go without getting too crazy. Nice looking boat too.
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Re: Engine choice help

Post by Whitebear »

In a commercial application, we ran a fleet of boats with CH3s on them and 425 HP 454s. I never saw a CH3 fail, but now and then we did have to replace the lower and upper bearing. Not a big issue as far as I am concerned. I really don't know how much over the 400 HP stamping you can go however. I seem to remember a couple with 500HP 502s on them but don't know much about them as they were not in our fleet.

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Re: Engine choice help

Post by Joe »

since you want to stay with the 2 - 1 and stump puller,for a budget build I would rebuild what you have with some good srp flat top pistons,roller rockers and a retro fit custom roller cam and lifters from Felber,up grade your valve train with new springs locks and such with stainless 1 peice intake valve and inconel,sp, exhaust valves and make sure you have a steel crank in it,and change out your intake for the edelbrock performer airgap. You will be amazed at the differance that will make in your boat!! just having the right cam from felber will be a huge up grade! I did this and more to my 454,and it runs GOOD! I turn an 80inch 3 blade super wide on the 2 mark with a 2.37 rotator,boat runs dry real well.
Another option would be to call Felber and see what he would up grade what you have for if your not mechanicly inclined to do it your self. Either way you will be VERY happy with the results and money saved!!
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Re: Engine choice help

Post by barhopper »

I would agree with Joe. If you can, go with Felber. He stroked my small block for a very reasonable price. I upgraded from a 2 to 1 belt drive to a 2.3 to 1 and put a 79" 3 blade R prop. It a whole different boat.
NotAGuide
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Re: Engine choice help

Post by NotAGuide »

I'm in Texas and it would seem cost prohibitive to send blocks back and forth to Florida. I may be wrong. Also looking at the website, $8-10k is on the low end of engine builds. Add new reduction, prop, and your bumping 18K for a boat worth very little. Just trying to be smart about the hole thing. This boat is intended for use during hunting season, 3mo. out of the year. I fish out of a totally different rig during the remaining year. Cost would be a totally different subject if I didn't already have too many toys.
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Re: Engine choice help

Post by Joe »

My first suggedtion was to build it yourself.If you cant rebuild it your self,get some quotes from shops near you,and weigh your options. The parts I listed will give you a very reliable motor. But buy your cam from felber if at all possible!!! Theres a lot of cams out there a builder with no or little airboat experiance will suggest,but Felber and waterthunder have the time trial and error behind them and have the cams figured out for airboats! and the wrong came would be throwing good money out to bad and dot get you all the HP you could have.
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NotAGuide
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Re: Engine choice help

Post by NotAGuide »

Thanks for your response and suggestions. I'm most likely going with a local shop and will take your advise on the Felber cam and lifters. Its just hard arguing with a local motor shop when they all seem to know whats best. I'd like to have a good idea of what I want when I get there.
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HuntingBigun
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Re: Engine choice help

Post by HuntingBigun »

Goodlooking boat for sure so freshing that bad boy up and be like a new ride. Here is a thought the cheapest thing in a engine is the block so if you put all new goodies head, crank rod etc in a old block hmmmmmmmmmm bet if you add up all the cost $$$ you may could buy a brand new replacement motor for the same with warranty. There is lots of options today for airboaters like we have never seen, cranking 600 hp out of 427 is nothing. pulling 550 out 364 done, new big blocks, new ratios for all drives. Call Keith at GTO Airboats they repower you name it with BBC, SBC & LS power plus his time is free :D :D :D 352 401-9070, :bigsmurf: :bigsmurf: :bigsmurf: :bigsmurf:
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Re: Engine choice help

Post by hmgm123 »

Hey Wayne can you build me a helicopter with a WT motor 600hp?? :D :lol:
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Re: Engine choice help

Post by HuntingBigun »

hahahhaa na but Rolls Royce power you bet I hate piston helicopters TURBINE POWER the only way :bigsmurf:
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Joe
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Re: Engine choice help

Post by Joe »

Its just hard arguing with a local motor shop when they all seem to know whats best.
Remember,there working for you.It`s what you want,not what they want! Thats whats nice about a custome built motor,it can be tailored to your needs,not another cookie cutter crate motor that works ok on your rig and all the others. Custome motors are made to your reduction and prop to optimize your set up.
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Re: Engine choice help

Post by HuntingBigun »

Joe Smedling, MAS, Waterthunder, Felber to name just a few are not CRATE motor guys they custom pick your grind for the power you want and where ya want it and what gas you want to run. The engine building industry is really change in the last 3 years hell you can buy a Rousch Racing 427 Ford for around 16,000 now that is a crate motor :D :D :D :D :D :D . One of my helio customers put one in a gt replica bad a$$. So just because a shop turns out bunch motor does not mean they build Crate Motor, the same goes for a local engine shop they have a nich too like customer service etc. bad economy has turned the big dogs to looking at all types of new markets for their product. Buying power is always in the numbers :D :D :D :D
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Joe
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Re: Engine choice help

Post by Joe »

Bigun,I would never tell any one waterthunder or felber build crate motors,they build custome motors,and are damn good at it.The rest of them have been know to. Havn`t heard any one else advertise custome built airboat motors tailored to you prop and reduction other than Waterthunder or felber,if they do good for them.
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Re: Engine choice help

Post by CactusJack »

Joe, read biguns post again, he said WT & Felber AREN'T crate motor builders.... they taylor make motors :wink:

Notaguide..... what about just finding a good running motor like yours at a wrecker and stick that straight in your boat? cheap and easy (as long as the replacement motor is good to start with)
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Re: Engine choice help

Post by NotAGuide »

Notaguide..... what about just finding a good running motor like yours at a wrecker and stick that straight in your boat? cheap and easy (as long as the replacement motor is good to start with)[/quote]

I would be in the same condition I'm in now. Not knowing what I have is part of the problem.

What are ya'lls thoughts on rebuilding the existing iron heads vs. aluminum rectangular port heads. I was under the impression that iron oval port heads were good for low-end torque? Would the aluminum be worth the additional money ($600 vs. $1600) in performance and weight?
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Re: Engine choice help

Post by Joe »

cactus,read mine again.I would never tell anyone thunder and felbers are crate motors. I read his as thinking thats what i thought of them,and nothing could be farther from the truth!
Notaguide,sorry for the off posts,seems to happen when differant opinions and contenants are invloved :lol: 8) Not to mention the whole not in person thing and the way you type is interpreted :shock:

I was told oval port where the best for low end,but my motor is a gen VI,mite be differant on a gen IV. give felber a call and tell him your interested in a cam and lifter set and ask him. It never ceases to amaze me the amount of info him and waterthunder along with many many others on this site will give you!!
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Re: Engine choice help

Post by corn bread »

are you sure on the hp on that ch3? the one I have has 600hp rating.
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Re: Engine choice help

Post by shiggs »

Good comments--I am not sure I would spring for aluminum heads unless advised by one of the experts for what your are trying to attain--I am guessing more power with reliability for the least amount of $.

I have 700+ going through my CH-3, no problems so far! :D
rost495
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Re: Engine choice help

Post by rost495 »

Others have said same, call one of the guys like Felber... tell him whats happening, and get parts from him. Take the block and parts to the builder with some more felber info... and take it or leave it.

I wouldn't drop the bucks on the AL heads if it were me in your situation.

I run a Felber 454 with iron heads, probably puts out 450 HP the way it is now, its not set up perfectly, 3 blade stump puller 78s, 2x1 belt. I"ve been scared on sand before, but it'll climb levees no issue with a light load, IE 5 doz dekes, 2 guys and gear and my extra "survival stuff".
ITs a 16 foot robicheaux?? not a light boat either plus poly.

What I"m saying is you can get to what you want with iron heads, and the right parts are super important on a build for an airboat. So if you get the right parts and then its just up to the builder to assemble.....

In the meantime if you are worried about blowing a motor up during season, go buy a junkyard 454 and make sure it runs etc... then pickle it and wrap it.

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Re: Engine choice help

Post by flying fish »

NotAGuide wrote: What are ya'lls thoughts on rebuilding the existing iron heads vs. aluminum rectangular port heads. I was under the impression that iron oval port heads were good for low-end torque? Would the aluminum be worth the additional money ($600 vs. $1600) in performance and weight?
The aluminum square port head would not be a good choice for an airboat application in the 5K RPM range. Square port BBC heads do not make their power untilk above 5500ish RPM. Especially in a small cube motor 454cid- Velocity- Air speed.

I wonder if an Aluminum headed, airboat designed 383 would produce as much power as the 454, and weigh much less. Might even outperform the 454 for the same money spent?
Also, the 383 might get considerably better economy.
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Re: Engine choice help

Post by flying fish »

quote="HuntingBigun"Goodlooking boat for sure so freshing that bad boy up and be like a new ride. There is lots of options today for airboaters like we have never seen, cranking 600 hp out of 427 is nothing.

Good looking boat for sure.
As far as the 600 horse out of a 427cid engine in the 5500RPM range? 23 degree??
On 91 octane?? -Correction factor!

600 horse out of a 23 degree 427 is nothing.
Come on now!
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Re: Engine choice help

Post by QuackKills »

NotAGuide....

Call Allen Bills at S&S Performance 281-445-7996 (Houston). We just finished with my 454 and I couldnt imagine being any happier with the results!

When you talk to him, tell him exactly what you are looking for out of your motor then tell him what your budget is and he will work with you from there. He will not BS you into buying a bunch of stuff you dont need.
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Re: Engine choice help

Post by rost495 »

Allen Bills is the best nugget of info I"ve found in this game so far. At least locally, as I can say Felber has not led me astray either. But for us in TX Allen Bills is no frills... he'll ask what you want and give you just that info and no other fluff.
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Re: Engine choice help

Post by moonrisn »

freshen up your 454 especially if money is a big roll player. Here recently we've been working on engines to make very good power in the rpm range air boats run in. With out of the box Edelbrock Aluminum Performer RPM round port heads(flyingfish is right, square port heads are not the heads of choice), Performer RPM intake, 10.1:1 compression, and a comp cam #280H hyd. cam you can look to make 1.08 hp per in. and 1.16 lb./ft.tq.per inch. That's 501 Hp @ 5400 rpm's and 542 lb/ft of torque at 4100,4200,and 4300 RPM's with a simple 454 bored .060" over on pump gas at 35.5degrees BTDC at 3600 RPM's. Assuming your tired engine is in fact a 70's era engine, your old engine may not be making 270hp. That's probably being generous with that estimate. You can't immagine the difference in performance .
yes, there is a lot more that can be done, but this combination has a lot of bang for the buck. A port clean up and port match to the intake will help both hp and torque, but a port and polish job will begin to shift the peak #'s up a little in the rpm range which is not a desirable trait. Remember, your goal is to max power for a combo to be most efficient at 5000 to 5200 rpm's and still idle well at 500 to 650 rpm's. This is not an expensive combination relatively speaking.
The whole package should run somewhere in the range of $6500.00. Remember, there are many ways to increase hp per in. But the big horsepower tamer is available gas. The next step to increase power and stay on pump gas is cubic inches and the expences begin to climb.

Allen Bills
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