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  #31 (permalink)  
Old 08-19-2010, 06:15 AM
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Originally Posted by Dirty Biker
How about this, I build me a 327 block with pistons meant for a 350 engine with 6 inch rods and my 283 crank using 6.250 inch connecting rods. With a motor with that rod ratio a stock 350 cam will not behave the same way, and I am curious to see how it does. Don't need turbos (but I wish), don't need overdrive dont need big heads because it will actually flow better with smaller ports according to this. A high rise dual plane manifold and an adjustable cam gear might be nice. Already have the block, crank, stock 283 heads, stock 327 manifold, and long tube headers. Fun stuff, thanks for helping me figure out what rods and pistons to use everybody. I wish I could run that setup thru desktop dyno but I dont have it... Maybe one of you guys do tho?

Here is a cool article on rod ratios, http://victorylibrary.com/mopar/rod-tech-c.htm

Here is a you tube vid of my old lady and dog and I riding my gt750 motorbike before I changed engines.

http://www.youtube.com/watch?v=2whyAQ35wkQ

If I dont like the results of my crazy motor I spose could sell the 327 block and crank to a corvette guy. Theres one on ebay right with the same casting numbers, block only, for 1000$.... woohoo... Mine is flint michigan made with the plug in front and everything.. Gotta love craigslist man...
Your "research is very classic, like a lot of people you pick and choose what facts apply to you; it seems that if it doesn't support your idea then you dismiss it. At this point it appears that you are overlooking more than you are considering.

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  #32 (permalink)  
Old 08-19-2010, 06:24 AM
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It looks to me like dirtybiker has had his mind made up all along what he is going to build and no amount of reason is going to change his mind . Appears he just wanted to know what rods to use with what pistons with his block and crank choice . I agree that it is not going to do what he thinks it will , but that is the engine that he has chosen to build . We at least gotta give him credit for thinking "outside of the box"
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  #33 (permalink)  
Old 08-19-2010, 09:47 AM
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Yes I have tried to make it clear from the begining that I was going to build this motor. To simply tell me it's a dumb idea without telling me why isn't really very convincing. I mean where do you get some of the things you some of you guys have said?? From books? What books? Websites? Which one? From people who tried this? Who? etc.. If its just an opinion heh cool, we all have them. Speculation? Cool but heh, its just that, speculation. Without evidence or facts coming from somewhere why should I believe your views over my own? Because you have built lots of motors that were nothing like this? Ha!! Thats why I want to try it. If it doesn't work, and I'm on here and some young punk posts a thread like this that wants to try it then I will be able to say, "Yeah man save your money! Build a tractor motor with as long of a stroke as possible, it saves on gas." But if on the other hand, if it does work, then you guys will maybe have learned something.

I think the geometry of the motor is an important consideration for its purpose. I think thats really all I was trying to say from the begining. You guys seem to think that it doesnt matter all that much but thats fine, I understand that you personally would not build this kind of motor. I say peak power is more important and you guys seem to think low end torque is more important. That about sums it up right? Point taken. If I felt that way too, I might just keep my 454, or better yet put a 4.25 inch crank in it and new pistons for even more low end power. But, I think that 454 motors are dumb!! And that 400 small blocks suck!!! Ok, granted a 400 small block with a 327 crank would be awesome!! Somebody even compared the 305 motor to the 302. Wow!! 305s are retarded!! Possibly the worst motor ever made next to the 267 and the 400!! Thats the dumbest thing Ive ever heard!! Muhahaha!!!! lol thanks you guys, I love debating this stuff
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  #34 (permalink)  
Old 08-19-2010, 10:27 AM
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Aah, hate to have to be the one that tells you, but 400 SBC's ROCK. The only thing better is a bigger SBC, which is done all the time. Why? Because it makes more power- EVERYWHERE! Not just down low, but all the way from the basement to the ceiling. A good 400 SBC makes more HP AND torque at 4500-5000 RPM than a 300 CID SBC will anywhere in its powerband! At its peak, the 400 SBC will be making tons more of everything.

If you think that a 3.75" stroke is for a "tractor" , I would hate to think what you'd say about a really big stroke- but it's a moot point. You have your mind made up. You're certainly not the first guy to come here w/a "world beater" idea that was less than... stellar, shall we say?

Take a look HERE. This was written 13? years ago. So, you see, there is nothing really "new" under the sun.

YOUR "problem" is what you want to use the engine for/in. A small displacement, high RPM 'drag' engine is not what a van that weighs 14,000(!!!) lbs. needs to get it down the road!

You also keep forgetting that you have to get that 7 TONS of van moving from a dead stop. That's a big part of where your idea of fuel economy will fall flat on its face. The other part is anytime the engine's required to make power, you'll have your foot solidly to the floor, w/all circuits flowing as much fuel as possible- or you'll burn pistons- or you will not accelerate- or even hold your road speed at any type of grade, w/o down shifting and revving hell out of the 300 cid, 3" stroke SBC. Even then- if the net torque isn't sufficient- you will slow down, not speed up.

The balancing act is to find enough power that you don't run the engine at the HP peak, but closer to the torque peak. The closer you come to running at the HP peak, the worse the potential mileage gets.

I'll close w/another link to an Isky Cams article where rod length (among other interesting subjects) are discussed. ENJOY.
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  #35 (permalink)  
Old 08-19-2010, 11:16 AM
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Thank you cobalt, I actually have seen that article on the 350 chevy should have built, Im sure it was one of the things that have helped form my intent on building this motor, especially the high compression part. I was just being silly with my opinions on the 400 sbc lol, I think that as long as you guys were spouting opinions I could dish out a few as well... hehe.. I met a guy with a 283 in his mid 1960s dumptruck, now I didnt run the numbers on the motor to verify it was a 283 and not a 327 but he said he was sure it was a 283 because it was his fathers and he had been around it all his life. Anyways he said that it did fine for such a small motor, even with 10,000 lb of dirt in the back. So, anyways, I started with the intent of putting this in my van because I am sure that it would work however I am hopefully going to trade it to my girlfriends mom for her van thats just like mine but a little newer and with a 6.2 liter gmc diesel. So I have an s10 that I can use this motor in as I was saying.. That would be a fast truck with any v8 in it compared to the iron duke it has in it now for sure.

here is a link to a 550 horse 302 chevy that got almost 25 mpg
http://www.hotrod.com/techarticles/3...une/index.html
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  #36 (permalink)  
Old 08-19-2010, 11:57 AM
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Quote:
Originally Posted by Dirty Biker
Thank you cobalt, I actually have seen that article on the 350 chevy should have built, Im sure it was one of the things that have helped form my intent on building this motor, especially the high compression part. I was just being silly with my opinions on the 400 sbc lol, I think that as long as you guys were spouting opinions I could dish out a few as well... hehe.. I met a guy with a 283 in his mid 1960s dumptruck, now I didnt run the numbers on the motor to verify it was a 283 and not a 327 but he said he was sure it was a 283 because it was his fathers and he had been around it all his life. Anyways he said that it did fine for such a small motor, even with 10,000 lb of dirt in the back. So, anyways, I started with the intent of putting this in my van because I am sure that it would work however I am hopefully going to trade it to my girlfriends mom for her van thats just like mine but a little newer and with a 6.2 liter gmc diesel. So I have an s10 that I can use this motor in as I was saying.. That would be a fast truck with any v8 in it compared to the iron duke it has in it now for sure.

here is a link to a 550 horse 302 chevy that got almost 25 mpg
http://www.hotrod.com/techarticles/3...une/index.html
And I'm sure the 283 powered dump truck gets great gas mileage . LOL
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  #37 (permalink)  
Old 08-19-2010, 12:05 PM
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I think it would get better gas mileage at 4300 rpm at 75-80 mph going down the expressway on flat land than a a 383 or 400 or 454, and would hold up better at that sustained rpm. I travel alot, I drive to Florida, North Carolina, Tennesee, New Mexico, Montana. I need a motor built for 4000+ rpm all day long in this current truck anyway.
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  #38 (permalink)  
Old 08-19-2010, 12:35 PM
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Originally Posted by Dirty Biker
I think it would get better gas mileage at 4300 rpm at 75-80 mph going down the expressway on flat land than a a 383 or 400 or 454, and would hold up better at that sustained rpm. I travel alot, I drive to Florida, North Carolina, Tennesee, New Mexico, Montana. I need a motor built for 4000+ rpm all day long in this current truck anyway.
And this false assumption is part of why your idea won't work.

A 400sbc making 75hp at 2000 RPM will be operating more efficiently (consuming less fuel) than a 300sbc making 75hp operating at 2700 RPM.
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  #39 (permalink)  
Old 08-19-2010, 12:38 PM
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Quote:
Originally Posted by Dirty Biker
I think it would get better gas mileage at 4300 rpm at 75-80 mph going down the expressway on flat land than a a 383 or 400 or 454, and would hold up better at that sustained rpm. I travel alot, I drive to Florida, North Carolina, Tennesee, New Mexico, Montana. I need a motor built for 4000+ rpm all day long in this current truck anyway.
It really depends on how hard the engine has to work to overcome drag . Back in 1968 my dad had a Galaxie 500 4 door with a 390 2 bbl auto trans that got 18 mpg and a friend of ours had the same car with a 300 cid 6cyl with a standard transmission and got 8 mpg. So it really does depend on how much fuel you have to feed the engine to overcome the drag factors , wind not being the least , especially with your van , at 75-80 mph. And any engine will hold up better if it's not forced to work hard constantly . Why do you think they put 800 plus cubic inch diesels in big rigs that only make 350 hp at 2150 rpm . It is because they can make that hp all day long day after day and run for 750,000 mi easily . By your reasoning they should run a 350 chevy and gear the truck to turn 4000 rpm so they can get the 350 hp . Faulty reasoning . But , feel free to try it .
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  #40 (permalink)  
Old 08-19-2010, 12:40 PM
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A Gen 6 502 w/an EFI set-up on it, tuned to perfection (aftermarket, of cour$e), headers, low restriction exhaust system, an OD manual trans, w/'appropriate' gearing out back, can get as much MPG as your 300 cid SBC buzzing at 4000-plus RPM at cruise, in a 7-ton vehicle.

When you encounter a grade or headwind (God forbid BOTH at once!), the 300 cid engine in the decidedly un-aerodynamic 14,000 pound van will be so overtaxed that it will not be able to make the grade/headwind w/o losing speed. Never mind that you'll have worn a hole in the floor from matting the throttle so much of the time. And forget trying to use a vacuum gage as an "economy" gage- it'll never see enough vacuum to get out of the red/yellow, unless it's idling or coasting downhill!

Through the years Chevy was driven- not by the promise of quick ET's- but by the requirements of their truck lines, to produce the larger and larger engines. If all they needed to do was to put long rods in an existing engine along w/whatever else you have in mind, don't you believe they would have done just that?

The OM's are in business to make money. The cost of developing a brand-new engine design (like the W-series or Mk IV) is in the many, many millions of dollars. They'd never spend that kind of money, were it not absolutely necessary.

Remember, the original BB "W" Chevy engine, the 348, was a truck engine first. The TD BBC's were truck engines to the core. Even the Dodge Viper V10 started its life as a truck engine. Early Hemi engines were used both in trucks and cars (and even industrial pumps, generators, etc.).

In ALL those apps, if the job could have been done w/a smaller, lighter, cheaper design, it surely would have. But the facts are what they are.

At least you have a good backup plan for the little mill- an S-10 w/that engine, one of AutoGear's Muncie's and a set of 4.56 gears- NOW you're talkin'!
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  #41 (permalink)  
Old 08-19-2010, 01:15 PM
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Originally Posted by turbolover
And this false assumption is part of why your idea won't work.

A 400sbc making 75hp at 2000 RPM will be operating more efficiently (consuming less fuel) than a 300sbc making 75hp operating at 2700 RPM.

Where do you get this stuff turbolover?!? On what basis is your logic? There sure are alot of variables possible there...

4100 rpms is what I have to work with. I am building it backwards, granted I believe you all when you say I should change the rear end ratio and/or add overdrive and keep my 454. But thats not what Im going to do. I think it will be more fun to build a motor meant for 4100 rpms. I better hang onto this 454 in case I change my mind tho... This stuff is just fun for me, switching motors, playing around.. I needed an excuse to build this motor I been planning for years, this is as good as any. I wish I would have never sold my el camino tho.


Adan,
Ford 300 straight 6 is a terrible engine, was a truck engine, and had a bad rod ratio. The 240 six was the same block, had a great rod ratio, and got decent fuel economy. I had a 1973 3/4 ton ford van with a 240 cid when I turned 16 years old, it was my first vehicle! I thought it was super cool. My dad and I went to KY from Florida one year, me following him in his new at the time ford areo star p.o.s. van. We gassed up at the same time and he was keeping track of the mileage. It turns out my big old van averaged about 20 mpg at 60-65 mph, the best he managed was 16-18 mpg with all that fancy efi, overdrive and new v6 engine! He had some people and coolers and crap in his, but I had stuff in mine too, and I promise I weighed more in my van than he in his! Then later on about 6 years ago, I got me a 1992 ford econoline with 300 cid with fuel injection. I worked on it trying to help mpg, and it ran great but never ever got better than 12mpg!! Maybe that old van was a fluke I dunno
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  #42 (permalink)  
Old 08-19-2010, 01:45 PM
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Dude...i thought this whole short stroke engine idea was goin into something small...and light! Not a HUGE van!!

I have a 72 econoline supervan, its massive...with a 302 ford. all stock, its a 10.5:1 motor from a stang/torino or something. so, its pretty much the same idea! Guess my mileage at 55...8 mpg...and thats driving CONSERVATIVLY!!

Now, my 78 trans am thats has a pretty good sized 400 poncho in it, with a BIG carb, intake, big cam, headers, 9.5:1 comp, stock sized rod, ported heads that runs in the 12's...gets 16-20 at 70mph, cruising at 2650 rpm.

The problem is that with a big, heavy vehicle, you have to rap the small motor out in EVERY gear, to not lug the ***** out of it! Like a v-6 pickup, it has too LITTLE of an engine to get good milage. The engine has to work harder, has more load on it, and sucks more fuel/air while its struggling to accelerate. The small car that has a big motor, you have to just rest your foot on the gas to get up to speed, pretty quickly too!


If you want to get some good milage from the van....

1. Used overdrive trans, I can get one from a salvage yard for $500.

2. Get those 5.?? gears OUT of that thing! Its not a roundy-round car! try some 3.73's or even 3.42's since it has all that GLORIOUS torque from the 454.

3. Sell the van, get an econo-box, build a MILD 283, and put in said econo-box...GREAT acceleration, and amazing milage (for a v-8) with an OD trans.

Side note! If an OD trans wasnt more efficient due to turning another gear...why does almost EVERY car mad past 1990 have one? hmmmm!!

But, if your dead set on this working...try it...then you will take it back out when your tired of not being able to run on the interstate, accelerate in an orderly fashion from a stop light and losing MORE mpg...

Oh ya...400 block with a 327 crank...its a race engine...dont thing about putting it in a car. NO bottom end torque to move you, yes it will scream, but also burn MASSIVE amounts of fuel!

some say cubic inches are king...torque is king...
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  #43 (permalink)  
Old 08-19-2010, 01:53 PM
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Originally Posted by Dirty Biker
Where do you get this stuff turbolover?!? On what basis is your logic? There sure are alot of variables possible there...
Assuming you eliminate as much variance as possible it comes down to a bore and stroke difference. Two variables; one if you just consider displacement.

If rod length made as much difference as you think it does there would be ong rods in everything, but it doesn't. Sure it makes a slight difference (and even that is often misunderstood) but the best thing you could do is a good rebuild of the engine and an OD trans.

Do you know what mileage a NEW 3/4 ton work van gets when its loaded down. There is no chance you will beat that with an SBC, you'll be lucky to come within 80% of that. If you want to "march to your own drum" and ignore what people are telling you you can expect 40% of that.
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  #44 (permalink)  
Old 08-19-2010, 02:53 PM
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Okay you guys, thanks for the advice. I may never get to try it if I trade vans, but if I don't trade and go thru with this, and I am wrong, I will be the first to admit it on here. Then you guys can have a good laugh and say " I told ya so!!" till your blue in the face lol
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  #45 (permalink)  
Old 08-19-2010, 03:15 PM
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I love discussios backed with opinions and no scientific data.
Think Im gonna re-discover what Otto and Ricardo did, hell, Who knows?

They might have both been wrong!!
Maybe, Boyle and Dalton were wrong too!
Do it dirty Biker,quit talking about i. You are burnin daylight!
That was an exellent article on long rod theory you reffered us to,at least one of these guys should read it, it will enlighten him,to say the least.
And PLEASE send pictures of aftermath!!
I would also like to see results of Dyno, better yet take the motor U.C.F. They've got the original Smoketron.
I also notice on the link Cobalt posted,the horsepower of this LONG ROD engine came in a lot earlier than what was it? 5501 R.P.M.
Time for word eatin for somebody here as it relates to another long rod post!!!
Funny the way things surface to the top and the s#OO sinks to the bottom.
Good reference Cobalt,I build all my motors with long rods.
If I could stuff a foot long rod in an s.b. I would do it!!!

Last edited by topwrench; 08-19-2010 at 03:30 PM.
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