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O/T - FWD gearbox ratios for off roader
DarrenW - 19/12/07 at 02:00 PM

A couple of mates of mine are seriously into off roading. Land Rovers are usual weapon of choice. They are trying to work out a design for a lightweight stripped out off roader. Their thinking is instead of the usual choice of front engine 4WD layout to try and get the engine more into middle of the car.

Current thinking is something diesel powered but being lightweight wont need to be such a large engine. Anyone know what the gearbox ratios for box fitted to the Ford 1800 diesel endurance engine (i think commonly found in '94 - '99 Escort vans)?

The idea is to weld the diff up and have one driveshaft running front axle and other running back axle. They want to check ratios out to see if the diffs they have will give decent final drives.

Any other ideas? They dont want to use rear drive gearbox due to the length of the boxes being too long thus pushing the engine position further forward.

Oh - and nothing exotic as locost is the strategy and if owt gets broken cheap to fix.

Cheers,
Darren.

[Edited on 19/12/07 by DarrenW]


indykid - 19/12/07 at 02:08 PM

i don't know what the ratios of landrover diffs are, but assuming they're above 3, you're going to be looking at whatever the top speed of an escort van is divided by 3.................

probably very capable off road with that much torque from the reduction, but it'd be hard work getting it up to speed. definitely not a road vehicle either.

i'd say the idea's fairly dead in the water unless you can find a fwd gearbox with some custom ratios to counteract the diff

if you could somehow get the power out of the gearbox before its diff, i guess it'd be feasible......but definitely not locost.
tom

[Edited on 19/12/07 by indykid]


DarrenW - 19/12/07 at 02:31 PM

I dont think out and out speed is a problem. They mainly do trialling (or whetever its called) rather than off road racing and mainly for fun.

Apparently similar machines have been seen to work already and they have various options for axles and diffs. For now they just want to do some sussing out hence trying to find out what the gearbox ratios are.


02GF74 - 19/12/07 at 02:31 PM

LR diff.

4.7 = Series, 3.54 RR, Def

transfer box ratios vary:
Series 1.15/2.89
RR/Def, 1.1 - 1.7/ 3.3


DarrenW - 19/12/07 at 02:35 PM

LR ratios are all known. Its the 1800 endurance diesel gearbox ratios we need help with please?

If not the ratios then if anyone knows what the gearbox is called ill try and do a search.


DarrenW - 19/12/07 at 03:04 PM

Will it be the BC gearbox? or IB5?

Ive found this for IB5, not sure what the diesel engine was fitted with but an approximation of all will give us what we need assuming it is the IB5. As i say im not looking for exact science - just rough figures at this stage. If the project comes off it will just be a bit of daft rather than serious competition vehicle.

Easiest option is to take a suzuki and strip it of unnecesary bits but they want to try and get the engine more into the middle.

[Edited on 19/12/07 by DarrenW]


mark chandler - 19/12/07 at 06:59 PM

We had a couple of people try this in the LR club I was in, no transfer box, just use FWD box sideways.

RR diffs with a rover 200 2.0 16v engine, manual box flat out around 65

RR diffs with a rover 2.7v6, auto around 70 mph flat out.

If any engine is looked at the Audi 18td is good as the CV's are bolt on at the engine.

The bad news, a seriesII/III g/box on a decent 3.5 engine will be faster and climb hills better..... The concept is fine, the reality does not live up, front end bounces about and you loose the grunt at low revs.


akumabito - 20/12/07 at 09:35 PM

Do a search on the pirate4x4.com forum. It has been discussed ad nauseum there. A few people have tried it, with pretty good results. Mind you though; the pirate crowd are hardcore rockcrawlers. The deeper the crawl ratio, the better..

Unless you're into speed-based offroading (hillclimbs, endurance rallies, the lot..) then don't get hang up over top speed too much. With a welded center diff the car's no good on the road anyway, and do you really need to go over 40MPH offroad?


akumabito - 20/12/07 at 09:51 PM

For a different approach altogether;

Mate a high-CC motorcycle engine (1 liter up), to a transverse car transmission.

That way, you'll have 6 sequential gears from the motorcycle transmission for high-speed use, plus four or five from the car transmission. Plus, of course the car's reverse gear.. Essentially giving you up to 30 forward, and 6 reverse gears..

It sounds strange but some Norwegian guys made a lightweight offroader this way which is very capable..

Drawback is similar to the earlier suggestion though; welded up center diff makes it no good on the road.

Is there any way to add a manual lock to the diff?

Anyhow, let me go find a vid of that buggy..

Here's the thread with the info... the vids are buried somewhere in there, I think...

EDIT: Vids!!

http://jeep.flipp.net/video/amund/Ei...ideo_00011.mpg
http://jeep.flipp.net/video/amund/video_00016.mpg
http://jeep.flipp.net/video/amund/video_00017.mpg
http://jeep.flipp.net/video/amund/video_00020.mpg
http://jeep.flipp.net/video/amund/video_00021.mpg

[Edited on 20/12/07 by akumabito]


NS Dev - 21/12/07 at 10:39 AM

me and a mate built a 6wd 6ws offroader on these lines, but used a fwd LONGITUDINAL engine and box from an early passat turbodiesel (same as audi layout) turned 90 degrees, gives a very short install but prob too wide for a landy.