Off road friendly aeromodding... My lil beast
I guess this can be a place for me to post my ideas/questions... And some day my build/results :)
Goal: To ecomod an SUV in a manner which maintains it's ground clearance, approach angle, departure angle, cooling system for long slow drives in the mountains, factory v8, and AWD/4WD. But to accomplish gains in FE which can justify the mods/expense :rolleyes: I love seeing all of these awesome cars and trucks getting crazy good FE! BUT, lowering, air dams, side skirts, full boat tails, nose cones, wheel skirts, etc etc, aren't always a good idea for some of us idiots :o :D Vehicle: 1997 Mercury Mountaineer, 5.0 V8, automatic trans, AWD (kind of the exact opposite of what you want to start with hahaha) Wish list of mechanical upgrades: exhaust/intake, electric rad fan, eventual swap of a true 4wd rather than awd transfercase (allow for RWD operation), and of course an OBDII gauge cluster for monitoring Now on to the aeromods! The Front: Issues are ground clearance, approach angle, under body aero nightmare, big tires to cause turbulence (they are only 30" at the moment, but could be upt to 33" in the future), and frontal area. This is my initial thought, could one merge a belly pan, offroad/prerunner bashplate, grill blocks, and an aero nose? http://i.imgur.com/nmKRhDIl.jpg If the following two noses got naughty and had a baby... Would it be a good thing or a bad thing? From an FE geared aero standpoint. I know we try to cut flow under the vehicle with airdams and side skirts, but would this allow for a decrease in frontal load and a smoothing of under body airflow? Since dropping the truck, or adding an effective airdam aren't an option. http://i.imgur.com/L0CIJVBl.jpg http://ecomodder.com/forum/member-we...-59-11-141.jpg (Weather spotters Matrix was the first example I came to) The Middle: Haven't figure out how yet, but full length and width belly pan... Again, the issue is clearance. Otherwise I would just drop down to the ground and go clear under the rear axle :eek: The Rear: Issues are ground clearance, departure angle, the wicked bad aero of the body in general. Idea is to design a boat tailish aero back, that will be mounted to a swing away bumper. Spare tire, recovery gear, jack, axe, etc etc to be stored in the tail section. My initial drawing has used the aero template from these forums, but I can't help but feel like it is shaped wrong when I look at the boat tails I see on this forum :confused: . I'm also wondering how far back it would need to go in order to see substantial gains in FE. Again, I know the bottom angle is wrong... But it's the necessary angle for departure. Ideas by Freebeard and Aerohead involve "wings" that drop from the bottom, or even having the lower portion adjustable for hwy vs "rubicon clearance" as aerohead described it haha :cool: http://i.imgur.com/lNAqrD1l.jpg Any thoughts on shape or length would be greatly appreciated. The sides would be the same sloping curve as the top, with all seams being rounded as opposed to "creases". A rear pan/diffuser would help assist air along it's path to the underside of the tail, although design of that unit hasn't been considered yet. Nor do I know if any treatment behind the wheels would be worth it? I have read through many pages of comments and designs here... And I totally get the ideas, just not sure how to apply them to my truck. Thanks so much in advance to any responses, and the community at large for all the inspiration! ~C |
Does it need to be aero to save fuel or money? How about a samurai or tracker converted to a vw diesel running on recycled veggie oil?
|
Get a scangauge. Half of your gain will come from driving smarter! See link in my signature.
Think about upsizing tires to lower rpm if doing a lot of freeway Raise psi when on road. |
Quote:
-C |
Quote:
-C |
Quote:
|
Quote:
Quote:
|
I am doing something similar, as I needed a good fuel economy vehicle to get to work and back, but I wanted more capable machine both on-road and off-road. I started with a Chevy 1991Regular Cab K2500LD 5.7L V8 that I already had that always got 10-12 MPG, and was able to get it up to 18 MPG average. That involved (in order of magnitude) a transmission swap (auto->manual), driving style, tire swap, air dam, fluid changes, etcetera. I eventually realized I would be better off starting with something that fit my needs better, so I got a 2005 Toyota Tacoma Access Cab 2.7L 5-Speed 4x4. Right out of the gate I instantly got 26+ MPG. The Tacoma is no slouch in the off-road world either.
I am not trying to dissuade you from “running what you brung” as that is always a good idea, just make sure you are going to be happy with the finished result before you put lots of time and effort into it. I have been there done that and it’s not fun. Also don’t discount the capabilities of your stock vehicle, get some decent recovery gear and a buddy and go see what your vehicle can do before you spend a bunch of money and time improving its off-road abilities. If you don’t already, look on expeditionportal, plenty of people on there doing incredible things with almost stock vehicles. Too many sites telling you to never even leave the pavement unless you are locked, lifted, 37s, and one tons. I have had many of the same ideas you have had with regards to underbody armor, but the trick is to make it strong enough to take the abuse, but light enough not to kill FE and acceleration. No point in the V8 if you have so much weight bogging it down that it drives like an I4. My idea is to use selective steel reinforcements in key areas, and to span the majority using aluminum and HDPE. Look up what many of the tube buggys have done, weight is a big deal to them and there are lessons to be learned on design and construction. Use your armor sparingly, as a protection, not as a first resort to just power through an obstacle. Mounting is always going to be an issue. Also, don’t create an oven, you need to realize the exhaust is like a giant heating element and if you trap the exhaust up inside a belly pan it turns into an oven. (An oven with your gas tank inside.) Plus the heat generated by your V8 exhaust is orders of magnitude more than generated by a hypermiled Honda Civic. I don’t suggest running the belly pan under your exhaust, it is possible but it takes some serious head scratching. For the approach angle/air dam dilemma, one method is to use something flexible, like conveyor belt, as the dam so that it can take some abuse. Another method is to use something that is quickly removable. Also, you could do both, which is my preferred solution. Tires are going to be a compromise. Either get all terrains, or run two sets one on-road only and one off-road only. At least that way you don’t wear out your offroad tires pounding the pavement. Also, I have found siped road tires do much better on slick roads and in light snow than deeply lugged off-road tires with minimal or no sipes. The top part of your boat tail looks good, but I think you have the sides and bottom too steep. Consider making a small solidly mounted boat tail (that doesn’t come out past the bumper) which can’t affect offroad abilities and would have room for your spare, and then making a removable tail extension. The burning question in the room: What fuel economy are you getting right now? If you don’t have one, get a ultragauge or other gauge and start learning your car’s patterns and rhythms. Miles from pavement, you need to know when something is wrong well before the car throws an check engine light at you. |
You might need to get this fabbed up custom, but a stout aluminum skid plate for your nose can serve on-road duty as a partial belly pan.
I wonder how hard it would be to make an air dam that was easily demounted for off-road duty. Cheap smoothie discs for your wheels wouldn't affect your offroading at all. If you lose one on the trail, well, I did specify cheap. |
Quote:
Quote:
|
Quote:
Quote:
I have spent many an hour reading and drooling over at expeditionportal... My dream is to live out of unimog or similar vehicle :cool: Quote:
Quote:
Quote:
Quote:
Quote:
I had considered a multi-part or removable unit, but honestly... That's just one more thing to store in the back of the SUV, something I was hoping to move away from. I guess when I get to that point, I'll play with cardboard and see what I can accomplish before deciding. Quote:
~C |
Quote:
I'm sure it wouldn't be hard to make it removeable, but how big of an improvement would I be looking at without sideskirts to prevent air from being sucked under and dirtying the air flow? |
Subscribing. I think what you're doing is outstanding and will be worthwhile! This is looking to be an important thread for those of us who have offroad ready vehicles looking to boost our FE. The great thing is that small gains (.5 - 1 mpg) are huge to us :cool: Over the course of 10-20 years, a smaller 4wd would cost less overall... though I doubt you'll drive your luxury Exploder that long ;)
Tires - look at 33x10.50R15 BFG AT KO's. My K5 will be getting these for all-purpose driving. A reduced contact patch for less drag, greater psi on the tread when offroad, reduced weight over a 33x12.50 and a greater height for reduced rpm on freeway. You'll be quad-winning :D |
Quote:
As soon as I get the rebuild on my 4Runner done, I plan on doing some aero upgrades that I've wanted to do for a while as well (among other things :D). Definitely interested to see what you come up with. As far as tires go, you can look at the Goodyear Wranglers. According to Consumer Reports it has the best rating for LRR among the A/T and offroading tires. I've personally used them and I like the ride on them too! :thumbup: |
nose/tail/wheels
I think Hucho would tell you to just skip the nose.The Mountaineer's nose would shame some passenger cars.A little lower with the airdam would be good.
The tail is good,just as you've rendered it .A good compromise. As to the wheel fairings,unless everything was really 'clean' up to them,and around them,they might just be embedded within turbulence. |
Quote:
As far as my luxury exploder goes, I've had her long enough to rack up more miles than most people will ever do on a single vehicle... Perhaps more than they will do on multiple combined hahaha. So unless another vehicle falls into my lap or this one suffers a fatal injury, I'll have her long enough to see savings and pay off the cost if I keep it on the cheap! See below for tire talk... Quote:
My current tires have been upgraded to 31x10.5R15LT Wild Trac's, the tread's as aggresive as some AT's out there but WAY cheaper. And I'm getting great wear out of them. Of course, great wear means it will be a long time before I try to stuff 33's under there ;) Unless of course I do some calculatin on RPM's and FE, and follow that up with some penny pinchin :turtle: Either way... I hope that my thoughts/ideas/questions, and hopefully follow through on some of them can help you guys (and others) in your search for better FE with your off roadin trucks. ~C |
You could do something like a conveyer belt air dam. Just hold it on with like 4 or 6 bolts and pull them off and throw the air dam in the back.
The 2/3 air dam on my suburban was good for nearly 1mpg. Why would you want mud tires? They are expensive, lower your fuel mileage, wear out quickly and need to be replaced well before they are worn out if you want them to be useable off road. I say run highway tires or A/Ts with bad ass snow chains off road. Or get a spare set of mud tires. You can throw nasty set of snow and ice chains on a bald high way tire and do things the most radically aggressive, expensive mud tire with full complement of tread can barely do. Another thing is most mud tires kind of suck in the snow and ice, I would rather have A/T tires. Ideally anything with chains. Chains protect the side wall and shoulder to some degree too, plus if you do cut the side wall on a highway tire, who cares, its a cheap high way tire. If you cut the side wall on the most radically aggressive, expensive mud tire that still has full complement of tread, well sucks to be you. |
Quote:
In regards to the airdam, That's really all you think would be necessary? That in conjunction with a belly pan? Does the belly pan need to be as low as the air dam in order to prevent an eddie or swirling pressure zone behind the air dam? ~C |
Quote:
Quote:
|
http://www.tankmodel.com/typ87-2.jpg
公司收藏 This Commanderwagen has a field modification that is a roller for the front valance. Something like this could establish a low stagnation point. http://t1.gstatic.com/images?q=tbn:A...3jp3IhfgJxFcc0 Or maybe a high stagnation point and prow like a boat? My current car is as low as I can practically get it, but for the next one I'm leaning toward a high ride height and heavily skirted and spatted wheels. A big problem for you will be the wheelwells. For the belly pan, consider Grimco - Substrates: Max-Metal, MAX-metal HD. It's like Polymetal or OmegaLite, but the aluminum skins are .30mm, about twice as thick. It's available in 4x8 and 6x10 sheets. |
Maybe some exhaust-wrap could be useful to decrease the overheat issue while using an under-belly pan.
Quote:
|
Quote:
I have A/T tires and they are over kill. I have 3 brand new highway tires, will start by putting 2 up front. Then run the A/T tires on the back. |
Quote:
Quote:
Quote:
In regards to design, would it need to be a tapered design like a true boat hull? https://encrypted-tbn3.gstatic.com/i...wIpI0w32vsEmph Or could it be flat like the duck tour amphibious trucks? http://www.tourrotorua.co.nz/pics/38...uck-tours.jpeg Clarification: would you want it tapered to try and cut through the air forcing air around the truck like the wake of a boat, or flat simply to try and provide a slippery angle for the air to hit and slide down under the truck? This is about as far from traditional aero mods as it gets, from what I can tell... Quote:
Quote:
~C |
Quote:
Quote:
~C |
I don't know how well exhaust wrap would hold up on an offroading vehicle, I have heard if it traps water it can make things rust out sooner. I have considered getting my exhaust ceramic coated, that would greatly decrease the radiant heat escaping from the exhaust. I think doing vertical walls to the sides of the exhaust to keep it from heating up the rest of the underside would definitely be a good start, but I don't know if that would be enough to be able to seal the pan off under the exhaust. If you don't have some sort of cooling or airflow the heat would eventually start to build, it just might take longer.
|
dam/pan
Quote:
http://i1271.photobucket.com/albums/...titled-6-2.jpg The airdam,if a little bit lower, would get the air around the nose,and restrict its access to underneath.The air below the airdam would have a straight shot to the rear. http://i1271.photobucket.com/albums/...ad2/Scans1.jpg The bash plate would be DIRECTING air under the Mountaineer,and even with a full belly pan it's a no-no.A great way to create front lift. From your sketch it looked like you could maintain your off road approach angle clearance if the airdam was even with the bottom of the suspensions naughty bits. The belly pan would be dead even with the bottom of the airdam. And if you do the pan,then you can think of a diffuser,which will kick in a little additional efficiency. |
Quote:
http://upload.wikimedia.org/wikipedi...hite_M3A1.jpeg I would favor the DUKW nose, with a roller in the bottom edge and a diverter. It would have angled arms on either side of the roller that hinge on the same centerline so it would stow up and forward under the nose or drop down to horizontal to do what diverters do. Nip off the two rear corners of the hood, and run the exhaust up one windshield post and a snorkel up the other. :thumbup: |
Ceramic-coating in the exhaust pipes is a good option too. The heat concentrated inside the pipes would actually improve the flow.
Quote:
|
Quote:
Quote:
I suppose, if I managed to get a true sealed belly pan... Then air from the engine compartment would vent within the belly pan and I could vent out the rear via a smooth duct to get clean the airflow back up before introduction to the rearward flow? That might alleviate some of the "heat" issues to begin with. And if it didn't work enough, I could throw on some mini electric fans to pull air out the back? I think that would also combat the dead zone of drag behind the vehicle if it were placed just right. Quote:
Also, your truck has a fully belly pan correct? Do you have any links or could you post any pictures of the belly pan? I'm having a hard time wrapping my head around how the rear axle/leaf springs fits into the equation when attempting to do a full sealed pan. I'm guessing you went under the axle since you have minimal suspension articulation and are low to the ground for aerodynamics. ~C |
Quote:
And that would be pretty sweet to run a snorkel and exhaust that way... But might be a bit much for my current daily driver :o I think you would have to run it up the pillar and then flatten it out along the hood to make it aero friendly? That way the exhaust was released evenly with contour of the roof? ~C |
Luigi Colani has proven that you can let a lot of air under the car given smooth under surfaces and in inverted wing-like body.
See this thread: http://ecomodder.com/forum/showthrea...iew-26432.html |
Quote:
~C |
Quote:
http://ecomodder.com/forum/member-fr...1373422495.jpg Somebody said Colani? http://ecomodder.com/forum/member-fr...wu5wo1-500.jpg |
venting/belly pan
Quote:
Mine has leakage at the front wheel wells,in the center,at the cab/box gap,at the rear axle,and rear wheel houses.It's far from ideal. I think that the only belly pan images may be at the 'Free Fuel Riding on the Wind' at EV World.com.,from back around 2005. When I do the oil and filter,I'm going to open an exit behind the radiator bulkhead area as Ferrari has done in the following link I would leave the diffuser alone.Morelli did do an aspirated rear bumper on the CNR 'banana' car,but it requires a wind tunnel to get that right. Air traveling 'above' the pan is robbing kinetic energy from the flow 'below' the pan.Also,you're bathing the powertrain in hot air off the radiator and exhaust.Good in winter,maybe not so good in summer.http://www.tamiya.com/english/produc...enzo/enzo6.jpg |
Quote:
Also, I didn't mean you liked war... Just that you seem to know a lot of the vintage vehicles :thumbup: :D ~C |
Quote:
This is the pic of your bellypan http://www.evworld.com/images/pknox_bellypan.jpg Is the belly pan coming down right before the axle to try and get it to jump the gap? I have assumed this is shot from the front towards the back? Also, I'm amazed at the uneven nature of the pan, I was fearful that it would need to be flat like the image of the ferrari's underbody. Speaking of the Ferrari, is the gap in the bellypan to vent radiator exhaust under the car, or is it simply an aerodynamics thing to help with flow on the front of the car and the creation of downforce with the ducting/splitter? ~C |
Quote:
|
Quote:
http://i.imgur.com/QvL6OoXl.jpg ~C |
Quote:
It is VW based — the WWII Schwimmwagen. This presents as having a chopped top and Porsche Fuch's wheels. The vestigal sill/grab-rail is all that remains after the stock front and rear fenders were cut away. It would make a much better boat with the airbags. Roostertails off the rear tires. :thumbup: I'd want it with a carbon-fiber tub instead of the original steel; and internal hydrojets, like a jetski, instead of the propellor. Oh, and inhub electric motors instead of the mechanical frontwheel drive. Unless that's a bad idea. :confused: |
Chillsworld, those Mountaineers and Explorers (especially with the 302) are great quality vehicles. I had a '96 4.0 OHV 2wd 5speed from FL, one of my favorites vehicles I've owned, and changed my mind on Ford. I got up to 24mpg with it. I just told a friend yesterday to let me know if he sells his daughters AWD Mountaineer.
On the tires, you could try a 235/85-16 in D or E load range, they are narrow but 32" tall and can be run at high psi, up to 85psi for E. On the transfer case, I believe that a 4x4 tcase will still have the front axle turning, just not the driveshaft, so not much savings IMO over AWD |
All times are GMT -4. The time now is 07:04 AM. |
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com