8 replies to this topic

[Pavel]

Right, this may prove useful to other people if we get a few good technical answers here.

Basically to run a mini at a decent speed (more than 10mph) on even but bumpy offroad (gravel, washboard dried mud, etc.), what is needed, what problems are most likely to be had?

1) Assuming a decent speed (40 mph lets say?) what will be the first to break?
2) What will work itself loose the quickest?
3) What should be checked often?
4) What modifications should be done to suspension/body?
5) Mud flaps... good or bad?
6) What to do to avoid exhaust catching on rocks, and what's the best way to secure it so that even if it does catch, only the exhaust tubing gets damaged and other damage is minimalised?

Hopefully someone will catch my drift and put in their 2p on this subject. A lot of talk goes on about road-racer cars, but nothing has been said of road-going rally cars (well, not much has been said). Most minis now adays that have the racing look are low and made for roads... But to those who might seek the thrills of offroading in their mini, this thread might prove helpful.. Especially if it can be done on the budget.

Why do I myself ask this? My mini needs to be able to run on said surfaces along the beach quite a bit, and i don't fancy breaking it (scratches, dings and dents are fine : )

Pavel

[Woody]

good idea to fit a sump gaurd , the best type go further back and protect the gear change remote as well .

[Bluemini]

Run the exhaust and gear linkage inside the car.
Raise the suspension to give better ground clearance.
Sump guard.
Seem weld the subframes and shel.
Strengthening plates at subframe mounts and shocker mounts.
Make sure all nuts and bolts are torqued up properly.

[miniman5]

i would certainly get a sump gaurd!

i have seen some where a mini with a gear linkage through the car if you get me! that would be a good idea! and as its a mini you want to strenthen EVERY thing and the usual checks aply to like tyre presure. oil and coolant and other things that you should check!

[philster]

the two main problems i had when grasstracking were the sump and exhaust. We fitted a sump guard and raised the suspension slightly which solved that and made different mountings to get the middle box on the exhaust as high of the groung as poss. If you don't need a twin box system then go for a single box and this will get rid of that problem. You could also fit a full skid plate under the car to protect the exhaust tunnel.

Other areas which caused less frequent problems were the top mounts for the shock absorbers in particular the ones on the rear arches, these used to break the welds if not seam welded.

[Dan]

Try strengthening the front shock mounts as well with a plate behind the mounting 'because theyre only screwed to a relatively thin panel, or you could weld the mounting in place but then it's hard to change if it bends. Definitely seam weld the front subby at least.
The best sumpguards are the RAC type made from Dural. The sledge front type has reinforcing for the front subframe as part of it, and the tunnel extension. Don't fit the cheap dress up type, they're rubbish.
Group A driveshafts and Allegro CV joints. And at least a competition diff pin, if not a cross pin diff.
Uprated (5/8") tie rods.
If your exhaust it still outside the car there are such things as ST exhaust mounts which are much stronger.
Use a spring to hold the dipstick down, and possibly some screws tapped into the block and washers to hold the edges of the core plugs (freeze plugs) in place which was an old competitions department trick.

How serious do you want to go here? You can do loads if you want but if you go to extremes then it will be nasty to drive on the road. You can use completely solid mount subframes and engine, but it'll be very noisy.

[Pavel]

Want it to be fine on the road, no need for extremem measures to be taken... Just want it to not fall appart on said surfaces, but it'll still mostly be driven on normal road. Interior will be kept as comfortable as possible...

Wouldn't higher softer suspension be advantageous on both offroad and onroad (on road it will just be more comfortable isn't it)

[philster]

softer would be more comfortable but would give more travel on the suspension (which means greater chance of bottoming out and arches rubbing)higher would cause the centre of gravity to be raised (because all the weight is higher off the ground) and also the front track becomes marginally narrower as you raise the suspension these in turn could cause more body roll and poor cornering. However most rally cars use higher and softer suspension to help deal with rough terrain so there are plusses.

[I_like_Opeth]

Run the exhaust and gear linkage inside the car.

Possibly latest reply ever but saves making a new thread...I'm interested in finding out about running an exhaust through the inside of a mini, wondered if anyone had any more info/pics/has it been done etc? What route has the exhaust taken and was it all heat wrapped?

Thanks for any info