So how much power does one really need in the bush ?

Submitted: Thursday, May 02, 2013 at 11:48
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3 months of pain and Super Patrol, a petrol 4800 GU , was ready - well almost, a few hours before the deadline for the Vic Desert test trip I had organized it finally got onto the dyno , rich as hell and coughing away it churned out a staggering 450kw flywheel and 1000nm of torque in the 1 minute before the dyno fan motor failed.

All credit for this car goes to the kids - I thought max would be a small supercharger but they persisted and worked night and day with only one goal - the most powerful tourer was all they wanted - this meant 4inch in/outlet and a big turbo twin high pressure pumps and endless other bits.

Hurried calls got it a night run on a commercial dyno where it was detuned to 420kw/285kw RW to make it safe for the trip and at 1pm it headed off for the all night6500km journey to the next 3 days of testing at Victorias Big Billy campground.

This was to be a 4wding test to find the most capable car - not a race otherwise Super Patrol would cream the crowd.

I guess we all would agree that you need sufficent power to be able to deliver strong controllable torque across a wide rev band. This torque needs to delivered smoothly and I would add you need enough to be able to spin the wheels anywhere if required.

It also needs to be reliable and you have to be able to feed it.

My neighbour sometimes looks over the fence with bemusement - he has the D4D Prado and sometimes pulls a van, and is content to plod along never needing more than its 100+ Kw, whereas we think his rig is just to slow to be safe.

Power requirement depends on what you are doing - in high country you need little - but in the soft and hilly sand country sometimes only momentum gets you through.

We also took 3 late model diesels, Hi-lux D4D , V6 Navara and auto Ford Ranger(Mazda) however for the biggest test it was just the 2 Patrols, my - not to far from standard 2010 4800 petrol GU Auto , and Super Patrol.
(Also took a tricked up 80 series but it died early - and an ML320 whose traction control made it a dog).

Super Patrol not only had over 400kw to my 200kw but also a touchy specialized dual plate clutch and with enormous 37in tyres which made my 33's look puny.

The critrea for the tests was simple, just get thru each section, didn't matter if you
took longer as speed was ruled out.

As well as the cars we had organized a bunch of bikes to help in reconnaissance and I arrived a day early and put up signs at the campsite reading "MX ClUB" to warn other potential campers and I also installed a 36ft telescopic mast with UHF to assist with comms.

Leading the way I came to the first hard hill test and went straight up , my car felt in perfect trim , its tricked up gearbox making changes in a milli-second, but then Super Patrol (a manual) didn't really need to change.
Super Patrol followed but high up on the hilly the track had already been churned up and next we heard a bang as the dug up track caused large front wheel hop and the 37inch tyres hit the standard Nissan alloy bullbar and actually twisted it down , while the car got to the peak ok it couldn't be driven until somehow the bar was bent upwards away from the wheel.





A high lift jack may have solved the problem , however without this the budding mechanical engineer grab 2 standard patrol jacks placing them back to back and almost did the job.



To finish the repair I put my car above the stranded car and jerked the Bullbar off the tyre and an 80km drive to Pinnaroo and a 9 inch solved the problem permanently.



Ok , Score was My patrol 1 --- Super Patrol 0
Next was another power monentum test and Supper Patrol was looking good until it tried to take a side track at a step soft sand junction.
No amount of power would help here and it instantly bogged.
I was above super Patrols second stranding but trying to use my winch began to pull my car over an embankment.

We had a tricked up 80 series below and he just made it to Super Patrol position however a bad gear change saw it shatter its gearbox - it was out but was able to be a dead weight and pull the Patrol back into line where it was able to be driven out.



In all the rescues dramas I never got to try this track section so we called this one even and the score was now.
My patrol 2 --- Super Patrol 1

For the decider we had a very special place picked out - and try after try we both made it.
It became obvious that Super Patrol and its sensitive clutch made it hard to get off the line in soft sand but once it did its huge power and tyres were nearly unstoppable.
I knew I'd win by attritionif nothing else in the long run.

But the last hill was up , I rounded its uphill corner off line , quickly realized this and stopped to back up and get on line.

I reversed to the edge of the track and to late realized that there was a huge hole and side slope hidden by some bushes and I was to close to the edge.



It was close for a time but in the end we got Super Patrol positioned and it gently pulled me off the sideslope.

It was now My patrol 2 --- Super Patrol 2

There were a lot of cat calls but the sun was setting and we called it even.

I still don't know the answer to my question guys ?

Perhaps the real story is that within hours of its first running Super Patrol survived the 1500km challenge at all.
Robin Miller

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Reply By: member - mazcan - Thursday, May 02, 2013 at 12:47

Thursday, May 02, 2013 at 12:47
hi robin
interesting post
and the pictures might well be deceptive
but looking at the tyres it doesn't appear that you aired them down for the sand driving
maybe for the reason with all that power you might spin the tyres on the rims with low pressure
ive always found that too much power nearly always bury's a vehicle rapidly in both sand and mud if its over used
a vehicle with a good power to weight balance usually performs better than one with massive amounts of power as its harder to control it or feather it through
just my thoughts from experiences
cheers
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Follow Up By: Robin Miller - Thursday, May 02, 2013 at 13:13

Thursday, May 02, 2013 at 13:13
Hi Mazcan

Good comments - the 37's on Super Patrol don't look like they are down much, partly because both cars are light and they are just so big that with 22psi they don't bag much but still have massive footprint.
Even though they are 17in rims, with so much power you could spin anywhere and risk of movement of tyres on rims was real.

Its a bit of a balance I guess and both drivers new the risk factors and made their own choices over 3 days.

I choose 16 psi which I was happy with.

There was one point where I thought the competition wasn't going to get out of the soft sand but did and gained momentum
very quickly for the sand hills with short runups that stopped other cars.

The much smoother delivery and adequate power I had certainly meant I achieved the goal with a lot less fuss.

The other car was however the crowd pleaser.
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Reply By: TTTSA - Thursday, May 02, 2013 at 13:41

Thursday, May 02, 2013 at 13:41
Hi Robin
Did you try the hill at White Springs, or Big K? They are the only two i've not seen a vehicle get over the top.

Cheers
Peter
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Follow Up By: Robin Miller - Thursday, May 02, 2013 at 14:24

Thursday, May 02, 2013 at 14:24
Hi Peter

The reconnasis team (6 trailbikes) checked out White Springs track and lookout but we opted for a bigger un-named hill we know.

The only named ones we did were around Thompsons Peak.

Not quite clear on BigK we did the track but nothing came up, I been in the area before also but its a little confusing with the hills and I do not have an exact co-ord for BigK.

If anyone can give it to me I can check our plots.
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Reply By: Axle - Thursday, May 02, 2013 at 18:33

Thursday, May 02, 2013 at 18:33
G/Day Robin,...Geez you like to have fun!!..LOL, ..Good question though ,How much power do you need in the bush?...I think when your bogged, its either way, ..you grumble to your self '.I wish this thing had more grunt',..or this thing just buries its self for no apparent reason"... A couple of yrs ago, i was involved in a golf course construction, and there was thousands of tonnes of sand spread by scrapers and dozers to shape the course, although everything was compacted after a few hot days and tradies running everywhere with their 4bys the top 300mm became a nightmare for everyone, as it dried out to become like talcum powder..lol.. The thing i'm getting at is that the contracters first on site where the irrigation installers whom i was working for and had nissan navara's, three of, the supervisor had a toyo landcruiser4.5l six pedo, and i had the landy defender... on that site the toyo just went every where and had everyone amazed at its speed and available power, the plumbers nissan utes proved to be almost useless with weight on, had to use to many revs to try to keep them going, and they just kept burying themselves, The Landy!!.. well no power!..With CDL in and second low it plodded around, did alot better than the nissan utes on the flat, but on the hill without the power to get the momentum it was no match for the toyo..lol....Bit long winded about nothing ..LOL..... But one thing i'm convinced about a Good pedo is better than a diesel anyday in sand work.


Cheers Axle
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Follow Up By: Robin Miller - Thursday, May 02, 2013 at 19:55

Thursday, May 02, 2013 at 19:55
Hi Axle

Its good to have experiences like yours.

I love theory but never go on about it until after I see practical examples of whatever it is.

So often its little things that make a critical difference.
You often here the wise statements like auto's are better in sand and on average they probably are - but when I ran two of my Patrols together my manual was better because sometimes when you hit the loud pedal it would try to change down 2 gears and the thinking time was enough on big hills to bog it down - but then I tweaked the auto in the latest car and when I say down boy she doesn't even ask how far she just does it before you can blink.
If you write down the various cars features this wouldn't come up on a fact sheet but it really makes a difference on those "what the hell is this" type hills.
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Follow Up By: gbc - Friday, May 03, 2013 at 12:18

Friday, May 03, 2013 at 12:18
My experience exactly. Apart from the latest powerhouse diesels, petrols have always been the best performance engines for any given vehicle, esp landcruiser. We chose petrol 80 and petrol 100 series then the v6 hilux when they were current as work vehicles for pulling trailers in sand. Don't ask about how much fuel we used, but that really isn't that much of an issue for a work vehicle anyway, and the usage only really jumped when you were driving in stuff that the average diesel simply wouldn't have made it in anyway.
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Reply By: Member - Laurie K (WA) - Thursday, May 02, 2013 at 23:45

Thursday, May 02, 2013 at 23:45
I have a Toyota 105 standard with a turboed Diesel, and we had been onto a beach at Cheynes Beach, and the soft sand coming out had us buried just as we were about to hit the top. I was in 2nd High, so backed off, tried 2nd low, and straight down - twice. Had a think about it, figured we had almost done it in 2nd high, so tried 3rd low, and straight over. The track out was a right turn, sharp left turn and then the soft bit. Tyre pressures 18 psi.

It seems that the lower gearing is not always the answer.

cheers
Laurie
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Follow Up By: Robin Miller - Friday, May 03, 2013 at 07:58

Friday, May 03, 2013 at 07:58
Some of those situations can zap your attempts all right Laurie.

I guess you have to be able to get the power down and have enough of it to gain the momentum for those short super soft bits.
Its no good having a really low gear and running out of revs just when you need them.

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Follow Up By: Member - Laurie K (WA) - Friday, May 03, 2013 at 09:46

Friday, May 03, 2013 at 09:46
In the lower gears, the car went down and just spun its wheels. What I had figured was if I could use the revs and have the wheels spinning less, then it wouldn't have the tendency to dig in - remember we had almost got thru in 2nd High. And so by taking it up a gear and being in low (ie 3rd low), we were in between 2nd low and 2nd high, and it worked. I guess my physics from school finally came in useful …….. albeit 132 years later LOL

Laurie
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Follow Up By: gbc - Friday, May 03, 2013 at 12:25

Friday, May 03, 2013 at 12:25
The first thing I'd think in that situation is that the tyres could be a few lb less for the situation. Huge difference between 18 and 15.
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Follow Up By: Member - Laurie K (WA) - Friday, May 03, 2013 at 12:48

Friday, May 03, 2013 at 12:48
That was the next plan. But rethinking gearing did the job, The rest of the day was easy with the tyre pressures. I don't muck around on sandy tracks. I put the Stauns on, decrease to the set tyre pressure and generally have no further issues.
In the Simpson Desert, we encountered ripped up tracks where guys were using supposedly 20 psi and gunning it over the dunes, where we used the lower pressure all thru and meandered over them. I have to add that it was in 2010 and the sand wasn't bone dry. I recall we backed down once and took an alternative track (again ripped up) with no hassles. Momentum and a steady foot will generally rule the day in my limited experience. Once the wheels start to spin, they cut thru like a saw. Limit the wheel spin and you tend to run on top …… that's the theory. And we were loaded up.

Laurie
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Follow Up By: Member - Laurie K (WA) - Friday, May 03, 2013 at 12:51

Friday, May 03, 2013 at 12:51
And here's a thought. Len Beadell built all those roads in sandhill country, and he didn't have a souped up 4WD. just a bog standard gutless Landrover, and he was on his own most of the time with the team following him.

So just how much power DO you need in the bush?

Laurie
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Follow Up By: gbc - Friday, May 03, 2013 at 13:14

Friday, May 03, 2013 at 13:14
I couldnt agree more Laurie. In the early 90's I punted a 1.5t 4wd tip truck around, doing building jobs on Fraser Is and the Noosa North shore. It was powered by a perkins s2s2 (mazda e2200 motor) punching out about the same kw as the wife's singer sewing machine. It was always loaded with building material and towing my trailer. Before that it was a Diahatsu F50, and before that a toyota stout and a g60 three speeder before that. Believe me I couldn't get rid of those athsmatic engines quick enough, but they certainly taught us all a thing or two about vehicle setup, tyre pressures, tyre selection and the rest of it.
We might not need it, it certainly makes us lazier 4wders, the next generation will laugh at the prep us lot do before hitting the beach, but given then choice I'll take as much power as you can give me every time please. :)
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Follow Up By: Member - Laurie K (WA) - Friday, May 03, 2013 at 13:24

Friday, May 03, 2013 at 13:24
Hi GBC

Your post reminds me of the legendary Tom Kruze. Again old Blitzes loaded to the gunnels, and little power.

Todays vehicles are so dumbed down with driver assisitance, it's bordering on dangerous I feel. Give me my old '99 100 series with its manual gearbox, and lack of electronics. The turbo certainly helped, and gives me more than I need I feel…… and yep, I want all of it :-)

Laurie
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Follow Up By: TTTSA - Friday, May 03, 2013 at 13:41

Friday, May 03, 2013 at 13:41
More power can simply get you into more serious bogged situations a lot quicker...............some times.
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Follow Up By: gbc - Friday, May 03, 2013 at 13:42

Friday, May 03, 2013 at 13:42
You knew the g60 with the side exit exhaust was working when your thongs started to smoke and you could light a cigarette off the floor pan. I look back with nostalgia at those times and think........ "*&%# that for a game of skittles" what was I thinking? ;)
There was a reason why we drank stubbies while driving up the beach back then - top speed was 30 odd kph, and you needed an anaesthetic to cope with the heat :)
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Follow Up By: gbc - Friday, May 03, 2013 at 13:45

Friday, May 03, 2013 at 13:45
Yeah, and diff locks will only get you stuck 20 ft further away from the tree you need to get back out again - heard them all. I'll take power and lockers, you take whats left ;)
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Follow Up By: TTTSA - Friday, May 03, 2013 at 16:35

Friday, May 03, 2013 at 16:35
I've got power and lockers, but I have seen excess power just get people stuck worse and faster, just sayin'
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Reply By: Echucan Bob - Saturday, May 04, 2013 at 08:42

Saturday, May 04, 2013 at 08:42
I get the impression most production diesels have sufficient power and torque to handle even the biggest dunes encountered on our desert treks. What seems to stop progress is loss of traction, or lack of clearance. Once the wheels spin or the traction control kicks in, then more power isn't going to help. Factors like overloading, and too much tyre pressure also contribute. As someone said above, if a bog 50's Land Rover can traverse all the Len Beadell Tracks, then the modern turbo diesel (even 4 cyl) should be able to. I personally strongly favour automatic transmission so as to avoid the interruption of torque in the clutch situation when changing gears in a manual.

Bob
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Follow Up By: Robin Miller - Saturday, May 04, 2013 at 09:49

Saturday, May 04, 2013 at 09:49
Hello Bob

I guess the average power of cars is going up and so other factors play a bigger part but I tend to think that power shortage remains a problem.

I note just how easily some types of cars like 200 series diesel do things.

In can be difficult to sort out these issues and its a reason I like to put vehicles up against each other in known situations.

All the factors you reffered to certainly do play a part and unequal conditions need to be ruled out to get real results.
Of the 6 vehicles I had on some of the tests the D4D late model Hi-Lux was so bad that it left the convoy and went back to camp by itself.
Earlier on in drive it had asked where the big hills were.
This car was the only one who just would not go below 20psi, so it was pretty obvious the car itself wasn't the issue.


I have come to the conclusion that about 1 kw of power per 15kg of car weight is required for cars which have no vices like peaky torque curves like 100series V8 or late turbo boost cut in like on 3lt Patrols.

My car was running 2600kg on the weekend so I only just made the grade.

When your marginal on power I agree that the others factors have a big input as does time to change gears.
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Reply By: awill4x4 - Saturday, May 04, 2013 at 15:37

Saturday, May 04, 2013 at 15:37
Pffft! 285Kw at the wheels from 4.8 litres.
My mates 1987 2 valves per cylinder 2.7 litre BMW made 431 Kw at the wheels and in it's upcoming new incarnation of 2.9 litres and an even more impressive turbo he's expecting around 600 Kw at the wheels.
Cheers Andrew.
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Follow Up By: Robin Miller - Saturday, May 04, 2013 at 16:31

Saturday, May 04, 2013 at 16:31
Fantastic Andrew - we should be out at Rocky Track next weekend and I can't wait to see if he can beat us up it.
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Follow Up By: awill4x4 - Saturday, May 04, 2013 at 17:06

Saturday, May 04, 2013 at 17:06
Maybe the Beemer might be a bit low but then we could probably do it with this one which my mate where I weld after hours also built the twin turbo system on.
Cheers Andrew.

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Follow Up By: Robin Miller - Saturday, May 04, 2013 at 17:21

Saturday, May 04, 2013 at 17:21
Great little car all right Andrew he must be proud of it.

400+ kw and 5500 RPM is nothing in the race car world , but interestingly one of our critrea was to keep boost to max 12 PSI as we don't want to have the first 4800 Patrol grenade.

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Follow Up By: awill4x4 - Saturday, May 04, 2013 at 17:35

Saturday, May 04, 2013 at 17:35
Robin, you haven't even scratched the surface on the 4.8 as they loooove boost.
Realistically at a rear wheel Kw of 285 your not making as much at the wheels as a healthy worked over normally aspirated 6 litre LS Commodore/Chev engine.
Has the head gasket been changed to a multi layer Cometic style gasket?
If so, then upping the boost is no issue with the 4.8.
Cheers Andrew.
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Follow Up By: Robin Miller - Saturday, May 04, 2013 at 18:30

Saturday, May 04, 2013 at 18:30
Your right Andrew but don't say those things the kids might hear you.

We already have a hopeless 6lt HSV Mallo which has taken out 2 thermostats in the last month and no one can figure out why.

But with this car it was put together on the kitchen bench and taped together just hours before this mission , the head hasn't even been off it yet and its done 200k - the detuning was done to stop valve bounce.
But with already twice the power of the competition (200 series/Hot diesel GU's etc) the next moves will be to make it reliable
and bullet proof as there is a possibility it may race in a class requiring original block and stuff like that.

The interesting thing I found though was that with all that go and 37" wheels it might well accelerate like hell but really, in the dunes,
the total package had little on my slighty warm 200kw 4800 Patrol whilst drinking twice as much fuel.

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Follow Up By: awill4x4 - Saturday, May 04, 2013 at 19:08

Saturday, May 04, 2013 at 19:08
Robin, from memory I think you said the car came with a Haltech Platinum ECU?
If so, and if you end up wanting to "push the envelope" then perhaps you could have a chat to Michael Kalaitzakis from Quickbitz.

Quickbitz

He has got quite a reputation for tuning Haltech ECU's and has a 7 second Nissan SR20 engined Toyota Corolla and he also tunes the worlds fastest SR20 engined Nissan Sylvia running mid to high 6 second quarter mile times.
We've done fabrication work for him in the past and I believe he's just shifted factory to Dandenong South.
His main job is building kitchens but speed is his passion and he's gained quite a reputation by all reports.
Cheers Andrew.
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Follow Up By: Robin Miller - Sunday, May 05, 2013 at 09:06

Sunday, May 05, 2013 at 09:06
I do get to Dandy south a bit so I may follow that up Andrew - mostly we have been dealing with well meaning amateurs but the car may go back to duel fuel.
Good memory - still can't believe we found that Haltech Plat Pro on the car , I may not have got my auto 4800 had I known it was available , and only for manuals.
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