starting in traffic on steep hills

[Nothing Special]

Thanks for the input. If I had a stroker of 408 CID and made 500ft/lbs of torque with a short duration/fast-ramp camshaft I would start making torque at 850-rpm. Would that be 80% of my maimum torque? Maybe that would be 400-ft/lbs of torque. Maybe that would get my Bronco started on Grand Teton hills. How many MPH should I be turning when the the torque is engaged at 850 rpm?

You're not asking the right questions so it's hard to give you answers. You do not want an engine that makes 80% of it's torque at 850 rpm. It would be like a tractor engine, good at pulling but too heavy and slow to be useful in a street-driven vehicle or a trail vehicle.

And what do you mean by "when the torque is engaged"? I've been assuming you are talking about engaging the clutch with the engine turning 850 (or previously 1000) rpm. But you typically are engaging the clutch in order to start moving, so the vehicle speed is 0 mph and asking "how many MPH should I be turning" is meaningless.

Now as for the frame. When I am done building I want to strip the frame down and take it to a black smith for heat treating and maybe cryo-treating. Maybe I can beef it up/thickening it.

I am open for changing the gear ratios of the NV4500. Is 7:1 low enough for the granny gear? What is the optimium gear ratio for use as an Alpine gear?

You haven't told us why you need such a torque-monster motor. Your only stated goal has been to start on steep hills in the Tetons. The stock 3 speed manual transmission with a stock engine will do that. A transmission with a granny low first gear will do it even easier, but again, you don't need a monster engine to do it.

You do need to be proficient at using a clutch however. And as noted above, some people are better served by an automatic transmission.

And changing gear ratios in a transmission is a huge job. Very, very few people would be capable of doing that. And there's no one answer to "what's the optimum gear ratio." It will depend on axle ratio, tire size, engine power curve and your own expectations, which are likely different from mine. Personally I think the 5.6:1 first gear of an NV4500 would be pretty good for most mountain driving.

 

[-8]

Well the gear ratio puts the engine at an rpm close enough to peak torque to start moving the Bronco half way up a very steep hill. I want a torque curve that starts off flat from idle to peak torque. Other wise the engine would perform very weakly and I would much dislike it. If the engine is suposed to perform weakly at low rpms I would have to increase idle speed significantly and would start moving at a higher speed. The parastatic drag of the engine would suffer. I would certainly turbocharge the engine for all concerns.

As for heavy and slow, I do think that aluminum cylinder heads and intake manifolds are useful. Again a small 289 V8 could be turbocharged for weight concerns and There should be an overdrive gear in the transmission. I have directly observed that high input torques for the curb weight of the vehicle greatly accelerates the vehicle. From there I can spin the engine faster, higher rpms or shift into a higher gear.


.You haven't told us why you need such a torque-monster motor. Your only stated goal has been to start on steep hills in the Tetons. The stock 3 speed manual transmission with a stock engine will do that. A transmission with a granny low first gear will do it even easier, but again, you don't need a monster engine to do it.

My only goal is for my Bronco to function like a tractor and never get stuck. I am not racing. I am not racing. And do not need to deduct that. I can start on a hill using a clutch. I had a Jeep with a 5 speed and I wanted to put a turbo diesel and have five or six gears and drive like a tank or a tractor.

I am shopping for an FMX and would trade a dana 60 rear disc brake for it. I also want a NV4500 and I am done with transmissions for life!

I do mean to for my Bronco to be a slow tractor with fantastic traction, great travel and flex, and incredible low end torque from a Windsor stroker with intercooled turbochargers! I mean to hit that FMX with lots of torque and I can do a manual valve body. I am not sporting.

 

[savage]

So do you want a gas engine or do you want to go with a diesel engine? This thread is all over the place. I know guy's using six cylinder in jeeps and can go almost every where. You do know you can press the quote button on the lower right of the post someone has written, so you don't have to rewrite it.;D

 

[sburks737]

-8
I don't know why so many are confused. The answer is simple, but you have two choices....
1. Go for dog at boat, or 2. Kentucky fried tongue clit cow

Hopefully my answers were as clear as your (fun) questions.

Your welcome,
Tyler

Thats funny right there!

 

[Nothing Special]

....My only goal is for my Bronco to function like a tractor and never get stuck. I am not racing. I am not racing. And do not need to deduct that. I can start on a hill using a clutch. I had a Jeep with a 5 speed and I wanted to put a turbo diesel and have five or six gears and drive like a tank or a tractor....

Keep in mind that a tractor has an engine that weighs 3 or 4 times as much as most car engines, yet only puts out 1/4 of the power. That's what it takes to have massive torque right off idle. It results in an engine that doesn't have enough power to be driven on the street and weighs too much to be used effectively on off road trails. That's what "functions like a tractor" gets you.

I think you need to get off the idea of having most of your torque at idle. If you want your Bronco to pull like a strong truck aim for an engine that comes on strong by 1500 - 2000 rpm and pulls up to around 3000 rpm. A turbo diesel will do that, but you can easily build a gas engine that will too, and it will be likely be smaller, lighter and cheaper than a turbo diesel.

If you want it to keep pulling strong beyond that you can get a well-built gas engine to pull strong from 1500 - 2000 up to 4000 - 5000 rpm (it's not easy to get a turbo diesel that does that). That would make your Bronco pull like a muscle car. Muscle cars and strong trucks are way better than tractors for street use.

 

[Broncobowsher]

Tractors get stuck. Plenty of pictures and videos on the web.

 

[half cab]

Even cats have a climbing gear.

 

[garberz]

I'm waiting for the punch line!

 

[-8]

I want an aerospace grade aluminum V8 diesel, intercooled, turbocharged and pressure injected.

 

[Skiddy]

I want an aerospace grade aluminum V8 diesel, intercooled, turbocharged and pressure injected.

just curious where would you find such an animal? got any links

 

[-8]

http://www.duramaxhub.com/45-duramax.html


http://www.duramaxhub.com/l5p.html

https://cumminsengines.com/showcase-item.aspx?id=369&title=V5.0+For+School+Bus+(2017)&#overview


http://www.foxnews.com/leisure/2013/10/07/cummins-new-v8-diesel-detailed/


https://www.bing.com/images/search?...hid=OIP.L4RGS35ZgMK3z4hw2kq86AEsDa&ajaxhist=0





https://www.youtube.com/watch?v=rhUnVOAE904


https://www.bing.com/images/search?...hid=OIP.kaZmLRuZAAeZ6PsxVvCI6wEsDh&ajaxhist=0


https://www.bing.com/images/search?...hid=OIP.Vmmmu_bpv_bW7KcUMyPrxQEsDg&ajaxhist=0


http://www.armyrecognition.com/isra...data_sheet_specifications_pictures_video.html

 

[Fastwest]

Tagged for fun

 

[jw0747]

I want an aerospace grade aluminum V8 diesel, intercooled, turbocharged and pressure injected.

No such thing available to the general public. If you ever happened to stumble upon an aerospace grade V8 diesel you couldn't afford to buy it. Cummins and Duramax engines aren't aerospace grade engines. Wasn't NASA's Titan rocket in the Apollo Space Program powered by an aerospace grade aluminum V8 diesel?

Switch to an automatic transmission for hill climbs w/o worrying about rpms.

What is an Alpine gear?

 

[69broncofun]

Get an automatic

 

[-8]

What breaks on an FMX when starting on steep hills?

 

[Nothing Special]

I'm not familiar with "FMX" so I had to Google it. What I found is a cast iron case automatic trans that seems to be considered really heavy and not as good stock as a built C4, and difficult to find anyone to build it because it's simply not as popular as a C4 or C6.

If that's what you are talking about I'm not sure why you're talking about putting both an automatic trans and a manual (NV4500) in the same vehicle. Unless it's just thsat you haven't decided yet.

Anyway, if you're asking what will break on an automatic trans when starting on steep hills, nothing will break. The torque converter will slip which will keep anything from getting shocked like it would if someone let out a clutch on a manual trans too fast.

But then again, nothing will break on a C4 starting on steep hills either. And nothing will break on a stock 3 speed manual starting on steep hills (unless possibly if the driver was really bad with a clutch). Starting on steep hills just isn't that hard on a vehicle.

 

[Skiddy]

I think the FMX since the case is made of cast iron. should get an aerospace aluminum made case would also save on weight

 

[dholder]

-8
I wonder how long you can keep this going?

 

[Pops68]

this is like a train wreck......every time I see the thread, I HAVE to LOOK at it to see the newest.......whatever.

Pops

 

[Broncobowsher]

Make sure to use the magnesium flywheel, it will respond a lot quicker.