Samurai Axle Trussing/Bracing & SPOA Perches

[Boyes]

So I've got one fully stripped front samurai axle (was leaking left right and centre) that I need to install SPOA perches onto.

My first question is Perches, I needed to move my perches in 40mm (I have a 410) what's the best way to ensure I have the correct castor?


Second question is Trusses/Knuckles supports... I've had a search of the internet and had a look on zukkicrawlers on trussing, but has anyone made their own trusses/knuckle supports in the UK?

I know Mike Harris ran low range off road items, they're cheap enough but with shipping and import get expensive.

I'm thinking install trusses then install the perches on top of them (so it supports the top of the whole axle) then make the perches to suit?

Any advice is appreciated, it's not that I can't carry them out but I'm just brain storming for the best option to give a good drive.

P.S. I can't go SPUA as the engine sump & diff will collide if I hit a bump (2" clearance I think it was)

Cheers

[ScottieJ]

What engine are you running that doesn't allow you to stay spua?? Personally I would rather tweak the sump, raise the engine slightly or move the front axle forwards than lift the vehicle 4" just for the sake of sump clearance. Mine is really close however it has never hit and I run the vitara sump on my 1.6 still with pretty much no lift, maybe 1-1.5", however my engine probably sits a tiny bit higher than standard. Loads of people say that you can't run the Vit sump but I've never had an issue. You have to remember that during compression the axle actually moves forward slightly as the lead springs flatten. You probably won't have much more than 2-2.5" up travel in the front anyway if your bumpstops are set up correctly to stop the springs inverting unless you have really arched springs.

To make sure you set the caster correct take some measurements using and angle finder before chopping the old perches off. use the diff mounting face or pinion flange for reference so that when you are refitting the perches you can sit the axle at the same angle it was when you measured the perch angle. I usually just set the axle up so the perches are perfectly flat and then measure the diff angle.

My knuckle gussets are just made out of some angle and have worked well, the axles themselves are sleeved with 3" tube with roughly a 6mm wall thickness and then there's a few small trusses.





I'll have to take some pics of the knuckle gussets as I haven't got any.

A different axle but should give ou an idea of how I set up the angles.

[ScottieJ]

Don't forget that going SPOA with good results isn't cheap either, you need to do a high steer conversion if you want it to handle well, longer props to reduce the Uj angles (prop spacers make the angles worse), longer brake lines, longer shocks, lower bump stops, possibly an anti wrap bar on the rear axle (depending on your springs) etc.

Even when it's done properly can cause a lot of other issues if the vehicle is used at speed on road as well as off-road with the increased propshaft angles and increased amounts of axle wrap.

I know quite a few people going back to spua from Spoa because of these issues.

[Jordi]

RockWatt can provide trusses and knuckle gussets. Not sure how much.

[ScottieJ]

TBH it's not hard to make your own trusses with some box section and an angle grinder.

[Jordi]

TBH it's not hard to make your own trusses with some box section and an angle grinder.

Think there are some photos in Ferris' project bodge build thread.

[Boyes]

I'll have to take another look I wanted to go spua but I have a diesel in, I've got a Robb storr high steer kit, I've got extended brake lines the only thing I'm missing which I was going to fabricate after was an anti tramp bar.

I saw you've got 6mm wall, I've just picked some 4mm wall up which will do the same job better than just the 3mm axle casing alone, and it was in the scrap bin at work.

How much sump clearance would you recommend to the diff with the truck sat flat? I didn't have much but also the oil pump was at the corner where it catches I think, but I will double check I don't like the idea of spoa but when I last went out it performed reasonably well with good on road manners(no bump steer tbh), it's just too tall for my liking! I like schu ducks build and originally wanted yj springs spua but the availability of them over here isn't too good.

Cheers for the advice, I'd appreciate pictures of the knuckle gussets

Another question, with you(or Tim Pink) sleeving the axle's what size U-bolts did you use to accommodate the increase in axle diameter?

[ScottieJ]

4mm wall would work fine, you just really need to take your time with any welding on sj axles as they will bend from the heat of welding if you aren't careful.

You don't need a huge amount of clearance, best to flex the suspension to check, lowering the bump stops or moving the axle 25mm forwards often helps as well.

what about going RUF with Hi-lux fronts on the rear like sierradan is doing? It should ride and flex almost as well as YJs all round.

I use samurai front diff side U-bolts all round as they are larger than the other 6. Dave at llama4x4 sorted me out.

[Boyes]

4mm wall would work fine, you just really need to take your time with any welding on sj axles as they will bend from the heat of welding if you aren't careful.

You don't need a huge amount of clearance, best to flex the suspension to check, lowering the bump stops or moving the axle 25mm forwards often helps as well.

what about going RUF with Hi-lux fronts on the rear like sierradan is doing? It should ride and flex almost as well as YJs all round.

I use samurai front diff side U-bolts all round as they are larger than the other 6. Dave at llama4x4 sorted me out.

Yeah I've heard they're very easy to bend..

Well I was looking into YJ's (My dad supplies leaf springs) but he can't get hold of them, but Navara, Ranger generally commercial springs he has a stock off so I was debating wether to try playing with an old set he has laying about, and I'll pass him the pipe and he can size me up some appropriately sized U-bolts, unless you know the size of the diff side U Bolts?

I will do some measuring in regards to sump clearance, see if I can move axle forward 1-2" as I wanted to extend the wheel base slightly for climbing inclines, and then modify the sump.

[ScottieJ]

25mm is about the furthest you can move the front axle forwards before the steering links bind on a standard steering set up spua, you wouldn't be able to use the high-steer spua but I doubt you'll have any issues selling it if you do go back to spua.

http://forum.suzukiclubuk.co.uk/vi ... =12&t=3752