Rear Subframe Alignment

[Guest MJTyke]

Whilst bolting in the rear subframe I noticed that the off side rear wheel was about inch half further away than the near side, being a novice thought nothing much more of it.

 

Further down the build and getting a bloke who knows about cars involved who said it would drive ok, but like a crab, therefore decided to rectify it, What a pain, I have seen other comments before I started the build but didnt appreciate what a quarter of an inch accuracy meant.

 

How common is this ????

[Guest Ant]

I've got that problem, and I'm nearing the end of my build. To be honest I'm putting off correcting it, which probably means that I will fail SVA for it, and the job will take a lot longer to sort.

 

How did you solve it? Mine seems to be a problem with the de-dion turb fouling on the folds in the two plates on the chassis. When I tightened up the bolts through the outer trailing arm holes one of the plates bent outwards rather than pulling the de-dion tube in.

 

Ant

[Guest MJTyke]

On the offside rear upright plate (supension bolts horizontally to it) ground it off, hacked approx 3/4" parallel to where it use to be, re-welded to the plate. On the other nearside upright plate packed with washers, seems ok. When I get the engine in I have access to a four wheel aligner so will have to wait to see but its certainly better.

[Big Jim]

Be careful, There is an offset unfortunately on the 2B (don't know if it's carried over to the subK or not0 but everyone has had to add a wheel spacer just on one side to bring out that wheel in line. If you try to centralise your rear sub frame, you can do more harm than good.

 

Can some of the 2B builders please confirm just how much of a spacer needs to be fitted?

[Jon Bradbury]

Jim,

 

As you know I have the DOHC kit and I noticed that the mounting lugs for the deDion tube were - shall we say - somewhat offset. On the DOHC kit there is this recessed floorpan, quite neatly designed, that snugly fits between these lugs. It is longitudinally offset by about 1/2" relative to the chassis rails because the lugs are out.

 

However, on fitting the rear hubs and wheels, I note that the wheels themselves appear to be exactly the same distance from the rear top outer rail of the chassis, which in turn means that the mudguards will look right on both sides (since they are attached to this rail - its a one piece fibreglass set as opposed to the s/s + fibreglass concoction you get on the normal 2B.

 

Hmm. Surprising.

 

Further, I think I might not need to alter the camber with one of your spacers, because it looks pretty good right now, although I haven't set the ride height yet so let's not prejudge.

 

I think Richard has done a pretty good job with this kit, and he's been very willing to discuss all this with me. He says it is all jigged so the wheels should be aligned, but the pipe bending machine has not so close tolerances, so my deDion mounts are offset a bit. Well, I'm interested in the finished look and alignment of the back wheels, and so far its looking good.

 

Sadly this doesn't help MJTyke & Ant, I just thought you might like to know...

[Guest Ant]

Be careful, There is an offset unfortunately on the 2B (don't know if it's carried over to the subK or not0 but everyone has had to add a wheel spacer just on one side to bring out that wheel in line. If you try to centralise your rear sub frame, you can do more harm than good.

 

Can some of the 2B builders please confirm just how much of a spacer needs to be fitted?

My 2B has the offside wheel about 3/8 to 1/2 an inch further out than the nearside. This is most evident in the rear coilovers because the nearside is almost vertical, but the offside leans out at the bottom! I also measured from inside the wheel rims to the bottom of the rollover bar - the 3/8 to 1/2 inch measurement is consistent here.

 

So ... do I leave it as it is and see what happens, or do I remove the tank and then the whole rear end and try to correct it?

 

Words of the wise appreciated here because I'm hoping to SVA in about 6 weeks time and my job list is already about 7 weeks long!

 

Ant

[Guest graham dockerill]

I've got the same problem but I think Jims answer is the easiest . When someone tells how wide the spacer should be I will find some other poor sod with a offset axle and go halves for the spacers as they come in pairs. Only joking regards Graham

[Guest TerryBarry]

The offset on my 2B appears to be about 15mm (9/16" to the unconverted), when determined by measuring distance between wheel and side rail.

 

However - how do I know that the side rails are symmetrical about the centre-line of the chassis ??

 

The coil-over units on the rear do both appear to be close to the vertical.

 

Terry

[Guest Ant]

Hmmm - decisions decisions. I don't want to dismantle it all, but I'm not happy with it how it is. What I really need is a 4 wheel tracking device. I reckon I'm going to do the following:

 

1) Try to pass SVA as it is. If the tester fails it (assuming he notices it, which he may not) then I will have to fix it, otherwise I'll leave it be for a bit.

2) Once road legal I'll see if the car goes in a straight line or not.

3) If not fixed due to one of the above then it will be done if or when I have cause to remove the petrol tank or do something equally big at the back.

 

Do 2B's generally go in a straight line, or is that too much to hope for?

 

Does anyone know of a four wheel tracking garage in or around Burton / Derby / Nottingham?

 

Ant

[Guest Guy]

Hi All,

 

Well I’ve just spent all weekend working on my back axle of my Sub(standard)-K.

 

It also has the offside wheel about 25mm further out than the nearside one.

 

The angled plates that are supposed to line up with the outer mountings of the swinging arm don't so I had to re-drill them to get the wheels strate.

 

The outside swinging arm bolts were at a different angle to that of the plates in the chassis which had to be bent to fit.

 

The rear mounting for the diff is 25mm too far forward so now it is also bent to fit.

 

Are the rear wheels supposed to have any camber on them?

is there supposed to be any tow in or out?

when I lift the back end off the ground are the springs supposed to fall out of the upside down front struts?

 

all this and more in the next exciting episode!

[Guest Paul S Usowicz]

Guy

 

I too am building a Sub-K and have not noticed the offset yet! As for the springs falling out, I installed the spring seats with the car jacked up so that with the trailing arms at their maximum extension the spring is uncompressed but seated top and bottom. Later on, when the car is fully built, I expect this to have raised the ride height to an unaceptable level, but I'll cross that bridge when I get to it.

 

Cheers

Paul S Usowicz

[Guest johnboymac]

Im building a sub-k and have to say that I dont seem to have noticed a problem with one side or t-other being out - what should I be looking for?

 

as to the diff plate being in the wrong place - this was my first thought as the dif seemed to stick 1" out the back of it - no amount of pushingpulling seemed to help. Then I raised the back of the chassis even higher (about 18 inches, got the trolley jack under the diff (damn near gave myself a hernia lifting the de-dion tube assembly) then jacked it up, at the more acute angle, everythin slotted in nicely (oh, I already had one of the front holes in and the other side half in - not tightened properly) and the diff went in behind the plate. the cutoff tubes on both sides came through and were bolted, diff plate drilled and fixed.

 

one side of the swingingdedion needed coaxing with an RH multitool - (damn big hammer) but otherwise all seems well.

 

so - what should I look for to see the potential problem?

 

cheers, John

[Guest Ant]

Mine's a 2B, not a sub-K.

 

To check you need to measure something on both sides. For me I measures from the top of my wheel rim to the bottom of the roll-over bar, but the sub-k is different so you'll need to choose something else to measure to.

 

The trend seems to be for the drivers side to be further out than the passenger side.

 

Ant

[Guest Guy]

I’ve sussed why my back end was wonky, it was too many pies!

 

No but seriously, the angle iron under the floor at the back is fowling on the Saline Dion tube so when I do up the bolts everything twists, it only takes a small error to mess up the back end.

 

I’m going to take the angle iron off and cut 10mm off each end and that will sort it. I hope this helps Marks original problem.

[Guest MJTyke]

Thanks for the info guys/gals

 

As far as the packing of one of the wheels by a spacer I am not happy with that since it could place the stub bearings under unnatural angles and stresses. I know that since the 2b is 2/3 the weight of the donor it is unlikely to cause problems in the short term, its a shame it didnt align in the first place.