New Jimny project - a few questions!

Yup, it's single overhead cam. So, will that mate to a G series Vitara auto (with a big drill to ease it's insertion!)?

I don't see why not as they are essentially the same engine, the Vitara is slightly taller.

I've always found Ray to be very helpful and with a good fund of knowledge of all things Suzuki!

Edit - insertion didn't go quite right!

Thanks Obarno. I'll find out in a few weeks!

Si

kirkynut wrote: Are you going to have magazine coverage of the build?

My plan was to keep a log of the build in photos etc then after the first competition it enters, write it up with a review of how the modifications worked in anger.

There have been plenty of simple build write-ups of vehicles in TOR etc, but rarely do they say anything about how well it performed and what changes you would make if you had your time over again. I think that would be more use to anyone reading it as it allows them to pick and choose which ideas to re-use.

As I've already mentioned, I'm going to use what is known as 'single link' suspension. You have an A frame, rigidly (no bushes) bolted to each axle with the apex of each A pointing towards the middle of the vehicle. You retain the panhard rods to stop the axle moving side to side.

This gives unparalleled articulation, although you do ger a change in camber angle as the suspension droops - but this doesn't seem to cause great handling problems.

Unlike most other Single-Link setups which use a big joint to connect the A frame to the chassis, I'm going to use two big universal joints (Tractor PTO types). The other side of the UJ connects to the chassis via a shaft on 'Pillow Block' bearings. The two shafts then connect in the middle through the centre of a differential. The Diff then bolts to the chassis via the same holes the crown wheel normally bolts to.

This means that the only body roll will be through the two shafts twisting, but the differential will allow the axles to articulate freely, but with the articulation on the front and rear being forced to be balanced.

This arrangement has one big downfall (as I found on my Vitara). If you are climbing a slope diagonally, most of the weight is on the down hill rear wheel and the least on the diagonally opposite wheel which causes the vehicle to roll badly corner to corner rather than side to side. I never thought too much articulation could be a bad thing!

On the Vitara, I fixed it by adding a hydraulic ram which could force the vehicle to articulate the opposite way. This worked fantastically well. In a cross axle, you could also increase the articulation to force the wheels on to the ground as well.

On the Jimny, the ram is going to twist one of the shafts as it enters the centre differential which will achieve the same thing. With the ram locked, the whole vehicle will be able to move up & down and pitch forwards or backwards, but there should be very limited roll side to side or corner to corner - good for side slopes!

Si

This is my proposed cage design.

It is constructed out of an internal hoop and rear stays to comply with the MSA regulations, made from 3.2mm wall, 1 3/4" OD CDS and the majority of the rest made from 2.2mm wall 1 3/4 T45 tube.



I'm going to extend the wheelbase to 99" which should make the tyres protrude front & rear beyond the bumper / winch - and give me a rear prop that is longer than 6"! I think the standard wheelbase was about 88".

The track will end up about 4" wider than standard as the wheels I'm using have negative offset. The previous owner has lifted the body by 2" - so it should be able to run at the equivalent of about 2" suspension lift with 37" tyres.

Any comments?

A bit of an update.

A Vitara auto box does not mate directly to a Jimny engine, or vice versa. Rhino Ray sells a conversion plate which allows a 1.6 Vitara engine to bolt up to a Jimny gearbox which is almost right, except the starter motor is in slightly the wrong place.

The Vitara flywheel is about 20mm bigger diameter - so the starter needs to move outwards by 10mm.

I bought one of Rays plates - then hacked it about with a plasma cutter to put the starter in the right place.

Ray, by the way, was fantastic! I spent a couple of hours and several cups of Coffee there chatting about stuff. The adaptor plate was about £80 which may seem a lot for a bit of laser cut steel - but the amount of work that had gone in to making it a perfect fit compared to doing it yourself makes it pretty good value. Having one cut as a one-off would likely cost that anyway.

I've just about got it in now. For some reason the two halves refuse to close fully.

It is possible that the torque converter is too thick, or it may just be that it's not fully engaged with the spline / dog which runs at engine speed. The dog is about the right depth for the amount by which it refuses to mate up by.

I'll have another go at it tomorrow - but it's very close!

Be careful forcing things, I recall that you could destroy the oil pump in a ZF box on a rangerover if you fitted the torque converter to the flywheel, then fitted the 'box. (the drive dogs get misaligned and smash the oil pump) The only way on a rangerover is to fit the converter to the box, and then attach the two together, finally bolting the converter through the flywheel.

I suspect the vitara box might be similar.