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  #91 (permalink)  
Old 08-21-2010, 04:25 PM
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you could probably sell all those vintage small block chevys you have to fund the operation. After the initial startup cost not including some time involved you can churn out bio diesel for about 1.10 a gallon

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  #92 (permalink)  
Old 08-21-2010, 04:27 PM
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This thread is intreage in the making and I like it, I won't pretend to have read each and every detail,,, DB one thing is for sure IMHO you are certainly a creative sort and can also fat finger in a really good bit of info and thought as others can. Its great to read and learn.

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This is just an experiment tho people, I wanna see what happens with the other extreme end of the scale compared to a 454 in a big truck!
I get ya here thats what I mean by intreage,,,something not yet tried or proven, hot rodding has no bounds, first time in 14000 lb van but what the heck.

Quote:
500 ft/lb of torque is nice on a mountain side,
This may be were the little V8 leaves you literally hanging, All the inertia is handled better by the 1500 rpm 454,,, the 302 may not spin at all just a notion

All in all if you can't build your dream, Diesel man Diesel,,,my 2 cents
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  #93 (permalink)  
Old 08-21-2010, 04:29 PM
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I agree . diesel in a big bread truck like that (P Chassis)
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  #94 (permalink)  
Old 08-21-2010, 04:32 PM
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The diesel will live a lot longer than the 454 in any heavy application like this.
A lot longer. 454 is a great motor but makes lots of heat and when you need it the diesel will give better power in the mountains and will probably give better mileage too.
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Old 08-21-2010, 05:17 PM
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"But the smaller 300 cube motor has twice as many smaller pulses of energy transmitted in the same duration of time. And wouldn't that make up for alot of an advantage of some crank arm leverage factor?"

NO, the only substitute for cubic inches is cubic money.

You are intensionally ignoring pumping loses and internal drag from bearing speed, lifter drag and compressing the springs twice as much, ALONG WITH turning the trans and rear end 2X AND those pumping loses. You'll also need to change pulley sizes to slow down the accessories or replace regularly.

Going to a large bore/short stroke compounds the pumping loses and throws efficiency out the window for 2 reasons:

the power-stroke piston must overcome the next compression piston which is traveling into a burning air/fuel charge , approx. 450psi X the surface of the piston face. Bigger pistons = bigger face = bigger loses x 2X rpm.

the larger pistons make for a larger quench area, where unburned hydrocarbons and CO are produced, quickly dropping efficiency and increasing emissions.
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  #96 (permalink)  
Old 08-21-2010, 07:37 PM
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Quote:
Originally Posted by oldBodyman
"Going to a large bore/short stroke compounds the pumping loses and throws efficiency out the window for 2 reasons:

the power-stroke piston must overcome the next compression piston which is traveling into a burning air/fuel charge , approx. 450psi X the surface of the piston face. Bigger pistons = bigger face = bigger loses x 2X rpm.

the larger pistons make for a larger quench area, where unburned hydrocarbons and CO are produced, quickly dropping efficiency and increasing emissions.
what about the short stroke allows longer rod, in this case 2.08:1 r/r giving more dwell, more time at or near tdc making more time for the flame front to move across the piston?

and "The power stroke piston must overcome the next compression piston" But part of that force it must overcome is caused by ignition advance isn't it? Shouldn't I require less total spark advance say than a 383? Or to any short rod motor because of less dwell time at tdc? I would think that is a contributing factor, giving some measure of advantage in favor of the shorter stroke/longer rod.

I really want a diesel and I agree its the best way for sure, do you guys know much about the 6.2 liter diesels? You can put a turbo from a 6.5 one and I understand A turbo helps fuel mileage on a diesel doesn't it?
On ebay I noticed the pistons and rings and bearings are very cheap if I needed some. Mechanical injection, means I could run straight veggie oil too right? Get this though, according to wiki it produces

Specifications
Engine RPO Codes: LH6 ('C' series, with EGR) and LL4 ('J' series)
Displacement: 6.2L / 379 cu in
Bore x Stroke: 3.98 3.80 in (101 97 mm)
Block / Head: Cast iron / Cast iron
Aspiration: Natural
Valvetrain: OHV 2-V
Compression: 21.5:1
Injection: Indirect
Horsepower / Torque (at start): 130 hp (97 kW) @ 3,600 rpm / 240 lbft (325 Nm) @ 2,000 rpm
Horsepower / Torque (at final): 143 hp (107 kW) @ 3,600 rpm / 257 lbft (348 Nm) @ 2,000 rpm
Horsepower / Torque (army): 165 hp (123 kW) @ 3,600 rpm / 330 lbft (447 Nm) @ 2,100 rpm
Max RPMs: 3,600
Idle RPMs: 650 + or - 25


only thing is that seems like it would need more power than that. Is that going to be enouh? I mean I guess that is enough if it comes with them from the factory but jeez... the School bus diesel would be the best huh, The dt360 does better, makes 210 horses according to this I found and the 466, 250. Thats better than the 6.2 liter at least. If I could shoe horn me a cummins 671 two stroke diesel and be done with it that would be something to brag about there..... gobs of torque and have a nice sound. I could pull a BIG lawnmower trailer too heh. That much torque would let me spin a tire if I tried I betcha.. I could run thunder valley dragway(I wonder what class that would be?). My dad drove a semi when I was a kid and he said the old freightliner would easliy spin the tires on dry pavement without even trying whith no trailer hooked up.

Last edited by Dirty Biker; 08-21-2010 at 07:56 PM.
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  #97 (permalink)  
Old 08-21-2010, 08:30 PM
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Wow man dirty biker, you wrote a book that time, I was gonna quote it but it was just too long.
I suggested a 6bt because I think it would fit your app. better than a 466,I really would rather not even talk about 6.2 really not a good thing for you,please dont ask whats wrong,just take my word for it.
Dt 466 would be a big problem to put in that van.
And as for the man looking for weed in a school bus......You know dirty biker,and speaking from personal experience again....I really wondered what exactly it was you had been smoking....Just kidding...no no, wait maybe not..
Anyway I just ran my 355 long rod motor down the road, put it through all five gears on Al. sr.91. last speed I remember looking at on the speedo was 65 and that was in 2nd.gear,Had plenty of power well below 5500, but Ill tell you what man , when it hit 5501 it lit the tires up,you know someone said on another post long rods were ok above 5500.
Hey if you need any help setting up that diesel,thats what I do for a living.
Right in the middle of double overhauls on MTU 16V2000s right now.I dont think you'll wanna put one of these in that van,I dont know....may be interesting to see that.
Dude, take my word for it,dont get into the 6.2 deal,you'll ragret it!!
And by the way,a well read guy like you should know,Cummins didnt make 6-71,Detroit Diesel did...71 series were 1-71 2-71 3-71 4-71 6-71 8n12-71 and in detroit diesel 2 cycle dying days and when Penske owned it they made a 24-71(2 12-71 blocks bolted together...Big time nightmare!!!)
Do not go the 2 stroke route either,engs.r just too big n heavy and fuel mil will be crap..

Last edited by topwrench; 08-21-2010 at 08:40 PM.
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  #98 (permalink)  
Old 08-21-2010, 09:16 PM
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Quote:
Originally Posted by Custom10
something not yet tried or proven, hot rodding has no bounds, first time in 14000 lb van but what the heck.

All in all if you can't build your dream, Diesel man Diesel,,,my 2 cents
So far no gas engine can match a diesel for efficiency. Early cars, which were heavy, started out with small bore/long stroke, and the engineers have been working back to that formula for a decade. I think the 283/302 type ratio was part marketing and grew out of the perception that it made more power because the big bore small stroke was a drag car philosophy since the 1940s. Gas was 17 cents a gallon when I was in high school, higher octane too.

There are guys my age and older still today, who will tell you with a strait face that a 327 is faster than a 350 because of the shorter stroke. According to that the 383 would be a real dog. And I'm sure that perception was perpetuated by the change in the way HP was rated just after the end of the 327. And of course Ralph Nader came along about the same time.

Lots of reasons why long stroke is cheaper to run; can't deny the math. I build small blocks, but drive Isuzu diesel daily because it saves me enough in fuel cost to buy a set of aluminum heads two or three times a year. There is plainly a lot more units of energy in a gallon of #2 oil than in a gallon of gasoline, that's mostly why, but research will yield that most diesels are also under square.
There is probably an engineer somewhere who if you told him you were going to spin up a 302 to pull a load more efficiently////he would just walk over to your desk and stick his pointer in your eye.


I was bored Duntov
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  #99 (permalink)  
Old 08-21-2010, 09:31 PM
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detroit diesel I knew that, I musta been thinking about cummins turbo at the same time as I was typing, theres a bell housing adapter on destroked.com

I was being silly anyways, I wouldnt want that heavy of an engine. The old van needs new springs and airbags now anyways, they hold air but the springs are sagging. But what about this: I bet my girls moms van with the 6.2 has a lower rear end ratio, so maybe I should put the 350 from my suburban in this van before I trade her which lightens the front end fixing the spring sag, then just use the 454 in that van with the lower ratio.. it won't matter that it doesn't have overdrive then. I don't know the ratio of hers yet, theres a tag on the back hopefully but everybody wins, she gets a better motor for spinning 4000 rpm and will still have enough power because she wont load it down like me, and I get a newer van with a liftgate and a big block that runs good. But if I could get that 6.2 running with one simple fix, I might have to try it.
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  #100 (permalink)  
Old 08-21-2010, 09:49 PM
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Quote:
Originally Posted by Duntov
So far no gas engine can match a diesel for efficiency. Early cars, which were heavy, started out with small bore/long stroke, and the engineers have been working back to that formula for a decade. I think the 283/302 type ratio was part marketing and grew out of the perception that it made more power because the big bore small stroke was a drag car philosophy since the 1940s. Gas was 17 cents a gallon when I was in high school, higher octane too.

There are guys my age and older still today, who will tell you with a strait face that a 327 is faster than a 350 because of the shorter stroke. According to that the 383 would be a real dog. And I'm sure that perception was perpetuated by the change in the way HP was rated just after the end of the 327. And of course Ralph Nader came along about the same time.

Lots of reasons why long stroke is cheaper to run; can't deny the math. I build small blocks, but drive Isuzu diesel daily because it saves me enough in fuel cost to buy a set of aluminum heads two or three times a year. There is plainly a lot more units of energy in a gallon of #2 oil than in a gallon of gasoline, that's mostly why, but research will yield that most diesels are also under square.
There is probably an engineer somewhere who if you told him you were going to spin up a 302 to pull a load more efficiently////he would just walk over to your desk and stick his pointer in your eye.


I was bored Duntov


One thing tho long stroke motors like the 383 still have to spin up pretty high to get the huge power numbers but with that long stroke the extra stress of slinging all that weight around means you have to get really good parts that cost alot. Not as important for my project already has a forged crank and the cheapie 6.25 rods I want will be stronger than stock so I will be golden, I wouldn't need a super quick ranp cam and roller like the 383 would need either.
But diesel, is the way to go if I could.
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  #101 (permalink)  
Old 08-21-2010, 10:06 PM
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Go diesel

Quote:
Originally Posted by Dirty Biker
One thing tho long stroke motors like the 383 still have to spin up pretty high to get the huge power numbers but with that long stroke the extra stress of slinging all that weight around means you have to get really good parts that cost alot. Not as important for my project already has a forged crank and the cheapie 6.25 rods I want will be stronger than stock so I will be golden, I wouldn't need a super quick ranp cam and roller like the 383 would need either.
But diesel, is the way to go if I could.
Diesel is the way to go, but I would think a 383 built right would produce more than enough torque @ 2700 or even less rpm to gear for 65 mph.. If you are looking for numbers look at torque only which would occur early on a 383. Horsepower usually cost fuel.

Just go diesel.....12 14 mpg would be about the best I would expect on the loaded van.
I did get 16 with a similar load with a 334, (stroked 305) but the right diesel might get 18/19 @55mph
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  #102 (permalink)  
Old 08-22-2010, 12:48 AM
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Quote:
Originally posted by oldbogie
In 1957 there weren't any interstate highways other than a few Turnpikes like the Pennsylvania and Ohio. The average speed on two lanes while posted 55 or 60 was closer to 45-50 if that as you moved from town to town and stoplight to stoplight. So bigger engines just weren't required and actually considered dangerous by the manufacturers themselves. All that got lost in the 1960's, especially as the interstates spread across the land making sustained high speed travel possible.

Technically there were significant problems, these cars rolled on bias ply tires and stopped with 4 wheel drum brakes, most likely unassisted. Power assist brakes and steering were extra cost options that most vehicles didn't have. Same for air conditioning, even in the desert southwest where I grew up, it was very, very rare especially on cars other than Caddies, Lincolns, and Imperials.

So much of the car just wasn't designed for sustained high speed travel and the power extraction for accessories was a lot less so huge engines just weren't needed and the perception of performance was a lot lower. The adults of the era grew up with flat head engines, cotton cord tires, and in some cases mechanically (cable like your emergency brake, but this was the service system for each wheel) applied drum brakes.

How bad were drum brakes even with assisted hydraulics the original GTO could not be emergency stopped from its top speed with the 389 V8. At the other extreme neither could the Ford Falcon with it's tiny I6. Add to that tire failure was common, with blowouts even with rayon that came between cotton and nylon cords time wise. Tires also formed bubbles in the side wall where the bond between the cords failed allowing air leaked thru the cord structure but not yet thru the outer layer of rubber. So these things would develop large bubbles or bulges usually in the sidewall but also in the tread.

The technology of highways and auto systems started to come fast in the mid '60s with nylon cord tires, bias belted tires, and disk brakes. Little things like man-made rubber began to replace leather for seals doing a much better job of keeping wheel bearing grease in place as well as sealing up engines, transmissions and differentials which tended to gush oil on the roadway and certainly parking places.

Wheel bearing failure was very common, you had to be careful to pack those bearings at least once a year, and if you missed the schedule you could count on their failure in the not too distant future.

These technical improvements that came in the very late 1950s thru the 1960s made the muscle car era possible. In 1957 getting and engine to 100,000 miles was an amazing event, most engines of the era would see a valve job around 50,000 and rings at 70,000 and be junked by 100,000. Tune ups to replace plugs, points, and condenser were something done about twice a year; with a point adjustment monthly, regapping and cleaning the plugs every-other month and a chassis lube about every 1000 miles, especially those new fangled ball joints. That's the reason why there was a gas station or garage on every corner and the average guy had to become car savvy because it took a lot of continuous work to keep 'em running.

The preceding era up thru the late 50's was an era of technical problems people don't even think about today, let alone know about, unless you lived during those times.
I lived through these times, but not in America...

All the same, I'm saying that most of this diatribe is codswallop!

Even Australian cars, living under greater stress than the V8s in Yankeeland, were doing 200,000 miles between serious rebuilds. Taxis 350,000 miles. De-cokes and valve jobs, perhaps, at 80,000 miles.

Cable brakes finally died with 1939 Fords. My father used to speak of people who drove on gravel roads at 70 and 80mph regularly, I have no reason to doubt that, and he was talking about pre-war in the cable brake times. As a family we regularly travelled at 60 to 70mph in our early fifties Holden 6 whenever we travelled, I don't think this would have been too different in the USA. I'm sure your roads were, for the most part, better and straighter than ours.

And I doubt our tyres were better than yours, though undoubtedly more lightly loaded. I don't recall a single tyre failure in any of my father's cars other than punctures.
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  #103 (permalink)  
Old 08-22-2010, 03:09 AM
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I can't begin to tell you how many 40's, '50's and '60's cars ended up in our junkyard well before 100K miles were on the clock- well and truly worn flat out.

Engines (and suspensions/steering/brake systems, for that matter) were not built from the same materials, cared for, or given the same quality lubricants that are routine today- not to mention the abuse that those vehicles got from the road conditions. Even the carburetion was such that a lot of unnecessary wear occurred on every cold start up. Trust me, 100K miles was a LOT on those cars.

The only tire failures I recall from those bygone days were usually related to below par recaps that were often used on vehicles that were already in poor condition, driven by guys who were using reconstituted 30W non-detergent oil (anyone remember those long-neck glass quart bottles of oil w/the metal spout beside the pumps? Also available "to go", in 1-gallon metal cans) due to the already too high oil consumption. Beaters, in other words.
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Old 08-22-2010, 03:18 AM
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Judging by what I recall from the era, and what I've deduced from various sources, it would most likely have been the high level of 'planned obsolescence' that created that situation.

Cars were traded annually or every second year, by 100,000 miles most cars were on to their third or fourth owner, they were worth little, they therefore got little attention.

Here we had very few people who traded cars annually or even every second year. I doubt that the cars were of any better quality.
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Old 08-22-2010, 03:38 AM
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Perhaps in Oz, you all had more open roads than we did. In any event, I agree that there was basically no difference in the 'quality' of an Australian vehicle made by GM or FoMoCo, and it's cousins in the States.

Stop and go driving is far harder on a vehicle- I think we can all agree on that. In the US, the towns and cities fostered just such driving. There were no real "open roads" (until the Eisenhower years and beyond) to drive in the manner that a turnpike or interstate road allows one to do today. And that is the type of driving that will allow a car to go 100K w/ease- not short trip, stop and go type driving.
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