Vitara trailing arm mod...

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Re: Vitara trailing arm mod...

Post by Anton » Thu Mar 29, 2012 8:31 pm

twiss wrote:If you're fabbing it up then there's no point in using vitara trailing arms.
You could pick something with stronger arms, ones that are easier to fit rose joints onto
You're absolutely right, and I will make completely custom arms at a later date - the vitara arms are being used because they're cheap and easily available, plus they're standard Suzuki parts - so come inspection time, the man from VOSA will probably be more inclined to accept them.
twiss wrote:Also for the middle link I reckon that mount wont be very suitable.
An "A" section mounted with regular bushes onto the axle and a rose joint attaching to the new crossmember would be better
Again, you're probably right, but for now I think I'm going to use the standard vitara A-Arm, just until the man from VOSA signs me off. I don't like the thing, but I'm sure I can make it work, and then make something more permanant later. I don't think I'll use a rose joint though, they tend to wear fast if you dip them in mud a lot, I'll probably use a johnny joint.
twiss wrote:The question needs to be asked though, if you're going to all the effort why not go 4 link.
It will be much better than 3 link, and if you're fabbing it up yourself it seems like a waste of time to take it all off, fab up 3 link, then stick it all back on again.
Might as well get it bang on first time as its a substantial mod!
4 link is nice, but a good 3 link should give me more than enough articulation. I do *want* triangulated 4-link, but again - the man from VOSA...
twiss wrote:You should also remember that if you coil convert it you will need to SVA test it to use it legally on the road
Not according to VOSA. As long as I don't modify the chassis, the vehicle just needs a quick inspection down at my local VOSA office, not a full IVA test (which is now so stringent, most of the cars made by the big manufacturers 5+ years ago would have failed today's IVA test when new!). Having said that, VOSA's rules are a bit like voodoo - even VOSA don't understand VOSA's rules.

Which is why I'm planning on making this in such a way that I can switch back to leaf springs if I need to - that is, use the leaf spring mounts for trailing arms, keep the leaf spring perches, and make the coil perches around/with/in the leaf perches.

If I make the coil suspension as "Suzuki" as possible, it's more likely to satisfy VOSA - if they moan, I'll switch back to leafs and ask them to inspect it again. The A-Arm then just becomes an anti-wrap bar. I don't want to IVA test the car, that's nearly impossible to pass these days, and costs an arm and a leg.
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Re: Vitara trailing arm mod...

Post by twiss » Fri Mar 30, 2012 10:35 am

RE: SVA Test

Unfortunately the SVA test doesn't exactly cater for 4x4s.
In the eyes of the law, a shell swap can still count as a major modification if not using a "like for like" unit.
As for the suspension, as you will not be entirely using the original suspension mounts, it does count as a suspension modification.
You have to retain 8 points of originality to not require an SVA test...

chassis / body shell = 5 points - Nope
suspension = 2 points - Nope
axles = 2 points - yes
transmission = 2 points - yes
steering assembly = 2 points - yes
engine = 1 point -yes

7 points

It may well pass it's MOT but if you have a serious accident you could be in for a lot of trouble.
In the case of an accident, and its been modded and not IVA tested your insurance could be invalidated and you could face a serious sentence.
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Re: Vitara trailing arm mod...

Post by twiss » Fri Mar 30, 2012 10:39 am

Of course it's up to you but if you have the nice IVA test pass then you wont be held responsible if your axle ends up going through a windscreen and killing someone
Twiss

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'93 Maruti Gypsy MG410

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Re: Vitara trailing arm mod...

Post by Anton » Fri Mar 30, 2012 8:54 pm

Oh crap.

I've added trusses to my axles. I'm at 7 points even if I don't change my suspension... 5 if I do. And they're Samurai axles, not SJ413 axles. Even if you could call swapping SJ413 axles for sammy axles "like for like" (that's a teeny bit of a grey area - they're not identical) they're still modified.

I have a Vitara power steering box that I was also going to fit, with PAS pump etc. So theoretically that takes me down to 3 points. That's assuming the G13A for G13BA engine swap (which they already know about, it's on the V5) isn't going to take me down to TWO points!!!

And with the 410 transfer box, I could be down to NONE.

And I'm never going to pass an IVA test, the boys on the Jago Geep owners club forums have made that *very* clear...

Where'd you get that points list?
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Re: Vitara trailing arm mod...

Post by twiss » Fri Mar 30, 2012 10:07 pm

The axles are only if you swap them so I think they will be OK.
Power steering is only really if you have to mod the chassis to do it
G13BA engine should count as like for like as well.
Its the same series engine at least

I reckon the shell swap will count, as will the different suspension mount.
I will go into the VOSA office on monday and check (just round the corner from my work)
Twiss

'93 Suzuki Samurai Sport 1.6 16v SU. Virtual lift, spring under, 31s
'93 Maruti Gypsy MG410

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Re: Vitara trailing arm mod...

Post by Anton » Sat Mar 31, 2012 12:01 am

Cheers. I'm now considering my options - I may have to sell the SJ and buy a Jimny if I need to IVA/SVA (I thought SVA's were a thing of the past?) the car, but I don't really like the Jimny's suspension setup as much as the Vitara's. Just seems to me that the vit would probably articulate a bit better.

I have a DVLA office (orpington) near me that apparantly a kit car expert works at. I may see if I can get him on the phone, or even get a meeting with him. I've SPOA'd the car so I'm now worried that I've lost the points for the suspension whether I go coils or not...

I'm as confused as I've ever been (and I've been rather confused at various points) now, because I looked up the 8 point system you spoke of, and found this:

http://webarchive.nationalarchives.gov. ... G_10014199

That seems to suggest that the 5 points you mention for the body applies to the body or the chassis, or the body *and* the chassis - so if I leave the chassis alone, does the body swap loose me those 5 points? Or is that only for monocoque constructions?

I may have 8 points in the chassis the engine and drivetrain. *Maybe*. I *think* the 5 points you loose for body swapping is only applicable in the case of a monocoque construction. But I just *don't know* because this is all a bit :er: like a cross between voodoo and scientology.

I originally got my info here: http://www.the-ace.org.uk/chassis-and-m ... ification/

Which suggests that as long as you leave the chassis alone, or at least don't *remove* anything from it aside from un-nessesary (non-structural, from the chassis point of view) body mounts, you're ok. It claims that adding crossmembers is ok, as long as by doing so you don't alter the dimensions of the chassis (i.e. make it wider or longer or deeper). I originally didn't click on the 8-point link at the top - should've done, not sure why I didn't - maybe it wasn't there when I first read it?
twiss wrote:Of course it's up to you but if you have the nice IVA test pass then you wont be held responsible if your axle ends up going through a windscreen and killing someone
Well, I was planning on making the mounts out of 6mm plate. My mate scottie (of HPOC.co.uk, not suzi club UK's scottie) has gotten me a binload of offcuts that are all more than big enough. I have enough to stitch together a small tank if I want. Should be significantly stronger than the mounts on a Jimny, Vitara, or even on a Landy or Land Cruiser.

If I do make any custom parts, that's the kind of strength I'm going for. If it's not over-engineered, it's not going on the car.

I think I understand why you said that - because of the bike hub thing, right? Well, I wasn't considering using that on the car, I wanted to build a "proof of concept" part and see what it would cope with. I certainly wouldn't fit something like that to a vehicle that was used on the road.

The car is getting new brake master cylinder, new calipers all round, rear brake disk conversion, new brake lines, new braided hoses, new handbrake cable, new handbrake drum/pads, 6 point roll cage...

You get the point. If I'm putting family members in it, I want to know for *CERTAIN* that it's as safe as I can make it.

But I also want it fully road legal. I don't want to sneak anything in that would make it otherwise - I don't mind using parts for the VOSA inspection and then swapping out for better parts later, but only if that's fully legal, and only to "smooth the way" with the VOSA guys, because the rules are so confusing that THEY often seem to have trouble interpreting them. I'm not the kind of person who risks that sort of thing - I don't sleep well at night if I have to worry about things like that. And that's not worth it.

I still want a mini-monster SJ Geep though. ;)
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Re: Vitara trailing arm mod...

Post by ianedwards » Sun Apr 01, 2012 12:58 pm

dudes, reading this has made me think, ive never heard of this before. how do you think ill stand on my tipper mod.

ian
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Re: Vitara trailing arm mod...

Post by Anton » Sun Apr 01, 2012 2:22 pm

Ian - I don't know. I *was* under the impression that mods are something the MOT man has to worry about unless they're so massive that either the vehicle's main structure (monocoque or chassis) is no longer "factory" or the vehicle's got so many non-standard parts that it's identity is now in question (for example, if you fit Suzuki SJ parts to a Dihatsu F50 until it's more suzuki than Dihatsu).

Now not so sure.

I would say "ring the DVLA" but...

Yesterday I rang them about my SORN application. According to http://www.direct.gov.uk/en/Motoring/Ow ... DG_4022058 if you want to SORN a vehicle but don't have the V5 in your name, you have to send the V5 application and the SORN application in together.

So this is what I did. I got the V5 back after a couple of months - a few days ago, in fact.

When I rang yesterday to find out about the SORN application, I was told by two different people that you can't apply for the V5 and SORN at the same time - because it takes 6 weeks for the records to be updated, so the SORN application will be rejected by the SORN department, as the vehicle isn't in the name on the SORN application.

Dealing with VOSA/DVLA does indeed feel like dealing with some strange mix of voodoo and scientology.
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Re: Vitara trailing arm mod...

Post by twiss » Thu Apr 12, 2012 2:03 pm

Well I've just been into the VOSA testing station and the man in the know says the body swap will be fine, as long as it has the same amount of doors and its roughly the same.
He said if you do the coil conversion it will definitely need an IVA test...
Twiss

'93 Suzuki Samurai Sport 1.6 16v SU. Virtual lift, spring under, 31s
'93 Maruti Gypsy MG410

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Re: Vitara trailing arm mod...

Post by Anton » Thu Apr 12, 2012 5:23 pm

Ah, thanks.

It's a little dissapointing that I can't upgrade the suspension. I was planning on making no changes to the suspension mounts anyway, so I might make it in such a way that the leaf perches on the axle are part of the coil perches, and so swapping between them is a case of jacking the car up, unbolting the suspension, bolting the other suspension in place, and lowering the car.

That way, at least if I get involved in some serious offroading I can take the other suspension setup with me and swap over at the site. Shouldn't be *that* much work with a decent hi-lift jack.

The real problem now is that I'm planning on going from a 3-door SJ to a 2 door convertable, and my local DVLA office (went down there the other day) is about as welcoming as an STD.

Went down there the other day to talk about the SORN. I was told that there was no SORN application on file (it went in with the V5 application, so the fact that they sent me a V5 suggests they got the SORN application). So I submit another. I'm told that because there's a gap between the date on the V5 and the date on the SORN application, I may be in for a fine.

I mention that I sent in my SORN application went in with the V5 application, and that they can't fine me because *THEY* lost it. In essence, her reply was "we can and we will". I'm then waved off and she presses the button that calls for the next person in line, without bothering to see if I'm done!

Nice. I'm well impressed with civil servants right now.
1985 SJ413VX (SJ50V) with SPOA, rear disc brakes, 31x10.5R15 Kaiman Malatesta tyres, an MOT and a lot left to do!

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