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15 hours ago, Mathew said:

I know the angle of photo is not great but as well as the camber being positive the rear toe looks to be in! Is this supposed to be like that? That would also raise the back end?

The front axle's tracking was checked and presumably adjusted by a tyre centre before I collected the car.  Of course i do not know what figure they used for their adjustment.  I haven't checked with a taught string yet but a careful visual check suggests little toe-out of the RHS rear wheels ..perhaps, according to a quick geometric calculation it's about -1/2 of a degree from being in line  My calc takes into account the TR4A's front-axle track being 1/2" wider than the rear.  Although not perfect I cannot see that as a significant issue.

I'm advised by my friend Rich, who has a few TR4's, that Katie is not (noticeably) crabbing. 

I investigated rear springs this afternoon, well the rear RHS one anyway.


^ I'd not done this before ..but the process is simple albeit laborious, insomuch as the half-shaft coupling needs to be undone from the diff.  With other wheels chocked, the handbrake needs to be off to turn the half-shaft around to undo all four bolts.  Sockets do not fit and so it's a two 9/16" ring or open-ended-spanner job.  Awkward when your working on the floor under a low car, even one on axle stands.  Otherwise, with the chassis supported., a trolley-jack under the trailing-arm takes the spring tension as the damper's tie-rod (one nut on the underside of the trailing arm) is undone.  Once that nut was removed - the trolley jack is gently lowered while the half-shaft is supported - to prevent it's gaiter from being damaged by it dropping down on the corner of the chassis rail.  That's all, the spring sort-of pulls out, but there's not quite enough room for the rubber or poly-bush) collar ..so that falls off.   

Comparing the new and old springs, sort of surprised me. . . .


^ Replacement spring left, old spring right.  Although first impressions suggest they're different, they are the same length (11-1/2") 

And when weighed, they both come out at 3kg (bathroom scales are not that accurate but close enough for this). This suggests they have a very similar amount of steel in them. 

And then when tested under arbitrary load, of 24kg (three night storage heat bricks) . . . 


^ they each compressed by the same amount ..just 1/4".   For all intent and purpose then.. they appear to be the same specification of spring.


The tyep of spring collars were shown to me when I visited M&T and those were black poly-bush types of 7mm thick. 


^ New 7mm thk polybush collar left, old 5mm thk rubber collar right. 

According to those in the know, because of the suspension's geometry ..the difference in spacer (or collar thickness) equates to just a little under double its thickness in road height. So the difference in thickness here is 7 - 5mm = 2mm + 1 for the rubber being squashed a little more = 3mm, so that'll make 6mm difference in ride height.   

I put the replacement spring back in, sitting on a poly-bush collar at the bottom, in the trailing arm, but with the old rubber collar fitted at the top. Took the car around the block (which here in Ipswich is like a lap around the pavé track at Millbrook vehicle test facility) ..and low and behold that side is now 5- 6mm lower.  Exactly as predicted but never-the-less worth checking for peace of mind. 

Very oddly, the positive camber now appears much better.??  That changing was not something I had anticipated, nor something I can presently explain. I'll check it again tomorrow.

So, if the springs are the same, and the collars make such little difference - I'm still a little baffled as to why the car is sitting 40mm too high. 


^ The spring saddle looks to be standard, aside from the couple of extra corner-triangulation gusset plates and its colour of paint. 

I did however note that the body used to rest on the old chassis' spring hanger, and in fact the inner-wheel-arch bottom flange was chafing through the top of the cup on the RHS.  Whereas the body, sitting on the replacement chassis, is notably higher. The gap between the top of this spring hanger cup and the flange is now possibly 12mm (higher). I've just checked the RHS and that has something like 8mm clearance now.


^ looking down into the spring cup of the trailing arm.  No spacer in there just the 7mm poly-bush spring-collar smeared in silicon grease. 

So where does any of this take us ? ..but around the block and back again ?

Well, my present conjecture is that the old rubber spring collar I fitted - was the best of the three removed from this car, and one was missing. Swapping back to this (best condition) one made 5-6mm difference in ride height.  Double that, and add a bit more for the even more squashed rubber of the spring's bottom collar ..and we'll have 12-15mm additional ride height, which together with the body now sitting 8-10mm higher on the chassis.. totals 20-25mm extra ride height.  Quite possibly the old springs are a little tied and so when loaded under the 450+kg weight of the back of the car ..that might account for the other 15mm or so difference in static ride height we now see.

Tomorrow I'll swap both rear springs for the original ones, just to try it and see. B)

Mathew, &/or anyone else.. if you want to come out to play, and to share your thoughts of what's going on, then please feel free to come across ..I'd be glad to see you.  Coffee or tea is on. 


p.s.  when fit recently repainted or powder-coated wheels, take a minute to run around the bolt holes with a blade to clean out the paint before fitting.  Possibly I should have done this before I gave the steel wheels to M&T to be fitted  ..but their mechanic should have known better and very quickly done it as a matter of course.  It's really bad practice to fasten structural parts or anything that's safety orientated onto a thickness of paint rather than metal to metal.  The paint will crack and flake, which may happen a few miles down the road ..and then the wheel nut will be loose.  Aside from that.. seeing cracked paint really pisses the customer off.



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11 hours ago, Bfg said:


p.s.  when fit recently repainted or powder-coated wheels, take a minute to run around the bolt holes with a blade to clean out the paint before fitting.  Possibly I should have done this before I gave the steel wheels to M&T to be fitted  ..but their mechanic should have known better and very quickly done it as a matter of course.  It's really bad practice to fasten structural parts or anything that's safety orientated onto a thickness of paint rather than metal to metal.  The paint will crack and flake, which may happen a few miles down the road ..and then the wheel nut will be loose.  Aside from that.. seeing cracked paint really pisses the customer off.



Its a reminder that nobody cares about your car as much as your self. A little thought is all that is needed sometimes. I doubt they did it on purpose but just didn't think about it when fitted. That's a problem trying to second guess or assume what someone will do. I wish you could buy hind sight glasses.

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Rain today, light at first progressively wetter..  as I'm not exactly keen on laying down and crawling under the car in the wet ..progress was slow.  Before I swapped the road springs back to what was previously fitted, I thought it prudent to first check that the trailing-arm's poly-bushes were not binding up.  When we collected the car, my friend Rich suggested loosening the bolts through the trailing-arm bushes, just in case they had been tightened up with the car jacked up, and were too tight to settle. With a host of other tasks and then fuel leaks I've only just got around to doing it.  

Rich had suggested I loosen them and then drive the car around the block, but I opted to do it a little different, not least because they would have needed to be re-tightened, and for that to happen I would have needed to jack the car up again ..for me to crawl under it.   So I first lifted the rear wheels onto blocks.  At the same time I loosened the bolts through the four trailing-arm brackets / poly-bushes (5/8" spanner & a 5/8" socket).


..you can see the sort of wheel arch gap I'm trying to sort out. 

with the front wheels loosely chocked and the handbrake off, so the wheels were free to turn as they settle, I loaded the boot. . .


^ I estimate that's about 95kg sitting on a 6x2" timber, which together with my own weight (105kg) bouncing up n' down on the rear wings and rocking the car from side to side, ought to turn the poly-bushes in their brackets / on their bolts for this loaded condition.

And then still loaded, and without  jacking the car up, I crawled under and retightened those bolts.  Once done, and unloaded the bricks out of the boot and popped around to the local shops in the car, so the wheels were then sitting normally level to the ground.  The result of my efforts was to make things 5mm worse (ie.., raised) on both sides !  ??

Btw the LHS has a bigger gap than the RHS rear arch ..hub centre to the arch, by about 12mm, despite it having a thinner collar fitted above its spring.

It's still wet so I'll change the road springs back to the old ones tomorrow.



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Half-shaft has now been swapped out..


^ the original from this car (top) and one I bought hoping it was OK below.  :huh: fingers crossed.

Rear springs now swapped out for those that were originally on the car.  

Five hours later, as I had to first swap the wheels studs over, and then had issues with one of the six studs holding the hub to the trailing-arm being loose / a stripped thread, the sliding handbrake mechanisms having no lubrication, and then again the handbrake cable mounting on the top of the trailing-arm being loose, no washer under it, and a binding nut.   It's all back together now but for doing the wheel bearing nut up.  Not turned a wheel yet so don't know what the ride height like is yet. 


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On 16/09/2021 at 10:22, Pete Lewis said:

did you re grease the telescope?     what was wrong with the old shaft ?

The spline of the old shaft was clonking loudly as I turned it by hand when under the car ..noticed most when the handbrake was off (wheel off the ground) and I turned the half-shaft when refitting the diff coupling bolts.  Floppy UJ's with slight but not significant amount of play.  It's very disappointing that this wasn't picked up on by M&T's mechanic and then swapped out while access was dead easy.  

My crawling under the car to do such jobs was the last thing I expected a week after having had the chassis swapped and the suspension, drive-train, brakes and steering, checked as they were being transferred from one to another.  No evidence that these, or any other grease nipple had recently been greased. 


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add in a stripped stud can be difficult to keep concentric when drilling  out  there is a drill jig but ...........how often 

small studs  you dont need to find a gorilla has been at work  they only need alight nip up 

mine 2000 has  greasers for the telescopes  but its not a frequent job

using poly on the trailing arms stopped any rear twitch powering out of a roundabout that can be evident 

if the telescopes lock under load 


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Yesterday Mathew (Puma-powered Spitfire) very kindly drove down from Norfolk to give us a hand. Two minds looking at the same problems from different experience-perspectives, as well as another pair of hands when measuring toe-in, camber and tracking, was very useful and he's good company and an interesting chap to hang around with.   Mathew also has toe-in checking equipment which gave definitive, if at some times a little confusing, data.    I might add that the confusion was mostly on my part because I'd never used such no-smoke-&-one-mirror tricks before.  I'm old school and so still use a length of cord along with a tape measure and a spirit level. 

First thing though was to do the final task of swapping the half shaft out and replacing rear the suspension springs for those that came off the car.  I'd assessed that they were of the same spec as the replacement ones, but I figured the replacements were perhaps less 'tired' than the originals ..so with the old springs back in the car - she might settle lower.  That final task was to tighten the central hub-assembly nut up to the prescribed 100-110 ft lb.  which with my background in old bikes rather than cars, leaves me a slight disadvantage. To me (having never had a hub apart to see the bearing assembly & inner workings) that big nut appears to be a wheel-bearing nut, which with old cars I thought was "pinched-up tight and backed-off by one flat of the nut"  ..then put the split-pin in and it's good to go. 

However, the Triumph workshop manual, under torque settings (at the very front a manual with no index) it says "Rear Hub Assembly ... 5/8" x 20 UNF stub axle ... 100 to 110 ft. lb."   In part this information is copied across to the Haynes manual but their semantics confuse things by describing it as "Inner driving flange to inner axle (IRS), which doesn't tie in with either my jargon nor their exploded diagram.  Anyways up, the figures agree and so 110 ft.lb. is what it was done up to.  

We then went for a few miles test drive around Suffolk's unclassified and b-roads, pushing the car into corners as fast as other road users would allow.  Aside from a quick stop to lift the top off the carb's float bowl to clear its needle from sticking again, the handling felt much better.  In fact the car in general sounded and felt almost passable, albeit with rather light steering and a tendency to over-steer in faster tight corners where subsidence made the road surface uneven.  However, when we got back and measured the ride height (having rolled the car forward and onto a level packing (plywood under one wheel) - the car is sitting no lower with these springs than those M&T fitted.  It also remains higher on the passenger side than the driver's.   In summary, I might only attribute the better feel of the car to having two people in it rather than just myself.  

Mathew then got his laser and mirror toe-in checking device out and we checked the rear axles  . . .

Toe-in of the rear wheels and Tracking..

P1390627s.JPG.84c0eb4ff890fec485ac10b723f5de9d.JPG    P1390628s.JPG.8df4cd8f095dcb652311b0b81e9325f2.JPG

^ Having set up the mirror to the LHS rear wheel rim, the laser's red dot is reflected back to its gauge and centred ..as a datum to compare with. The laser is then left untouched as the mirror is moved to rest against the rim of the RHS rear wheel.  The reflected red dot now tells us what the difference in angle is.  As you can see in the second photo., that was recorded as about 13 minutes of a degree (ie., about an eigth of a degree toe out).   The workshop manual tells us that the axles (front and rear) should be set zero (neutral) to 1/16" toe in.  I could convert from 1/16" to degrees but for the time being we'll leave it ..as to adjust the toe-out to toe-in would involve re-shimming inbetween one trailing arm bracket and the chassis rail.  And Mathew reckoned that even removing just one shim would result in too much adjustment.. He has a Triumph 2000 with much the same IRS suspension as this, so I'm happy to take his word for it.  In any case although the device highlights this tiny inaccuracy, it doesn't tell us which (left or right) trailing arms is out of alignment.

Me, well I'm old school.. and I had a piece of cord to work with. . .


^ with the cord tied to the exhaust tail pipe ('cause I'm right-sophisticated with my engineering set-ups) and pulled taught around all four tyres (the cord clearing the sills and otherwise pretty close to being parallel to the ground) we could then use a tape measure or rule to measure front and back dimensions between each wheel rim and the cord).  Those dimensions were of course in inches or mm, and it's intuitive to see which wheel was pointing where.   NOTE : we did allow for the difference in width of front and rear axle tracks, with 5mm packers under the cord on each rear tyre.

The rear wheels were very close (measured as about 2 - 3.5mm out of track) but the front wheel tracking ..which I was told by Mark had been done by a commercial tyre centre in Wolverhampton, was 10 - 12mm toe-out.  Oops !  It is meant to be 0 - 1/16" toe-in.  

So we went for lunch ;) 

Thereafter we adjusted that, at the steering rack's tie-rods (..either end to try and keep the steering-wheel straight).  For this task - the laser & mirror was helpful and very much more precise than the cord and tape measure.  Accordingly, I've now set them to about 3-5 minutes toe in, but I also accept that's a temporary setting, as there's play in the steering rack itself. 

At the local TSSC evening meet-up a member kindly flagged this, as most likely being the rack's inner ball joint.  Again this is something that I would have thought M&T's mechanic should have noted and advised on ..perhaps asking if I wanted it exchanged or refurbished while the body was off.   It's noticeable enough, as is a wobbly rear wheel bearing, that they otherwise ought to have been flagged by the MOT.   Anyway, they're now just other items on my job list.

Checking the cord, now with the front wheels in line, revealed that the rear track was so close to being correct as to be of no concern. The cord, previously held out of true by the front wheels - corrupted our previous measurements at the rear.  Measured again, the rear wheel rim to cord dimensions were so close, on both sides as to be negligible, and indeed (if I recall correctly indicated) 1.5mm toe in.   I'll check that again because the recollection contradicts the laser readings, but 1.5mm, in or out, on a 15" rear wheel is pretty close ..and it may yet adjust when the ride height and the wheel's positive camber are corrected.    

Our second test drive confirmed that the steering was very much better now, with a little feel (rather than being a little too light), and so very much better feel in corners, in particular left-handers for some reason.  I still felt that the car was rolling over its suspension and skittish when pushed (or over pushed !) ..but still we had achieved a noticeable improvement for very little effort.   I leveled the floor by the patio before driving straight in (no reversing to wind-up the suspension) and we checked the ride height again and also looked into the positive (leaning out at their top) camber of the rear wheels.

Ride Height .   The ride height measured (wheel centre to underside of wheel-arch rim) as 405mm on the RHS, and 425mm on the LHS.  Checking against a spirit level across the car, we've determined that the LHS wheel-arch is 10mm higher than the other (down to body tub, wing shape or where it's fitted), so the passenger side will look higher by that amount.  The body is sitting some 8-10mm higher on this chassis, probably thanks to having new rubber body-mount pads inbetween the two.  And the poly-bush spring collars are each 3 - 5mm thicker than the old rubber ones and so, due to the geometry of spring to hub distance, would raise the rear suspension by 6 to 10mm for each collar.  x2 collars for each spring = 12 to 20mm increase in ride height.  I'm not sure I can do much about that, but to fit shorter / lowered springs.   But I'll wait to see how correcting the camber changes things.

Camber.   Unfortunately Mathew's camber checking device wouldn't work on this car, because there is no flat surface on the wheels for the device to fit it against.  Apparently it's often set against the flat of a brake disk.  So back to old-school ways of doing things.. ie., a spirit level set vertically from the ground and resting / steadied against the wheel arch. From this straight edge datum its easy enough to measuring the distances to the wheel rim. 

The measurement itself is meaningless (because of wheel arch brow dimension is not accurate) but the difference in dimension between that taken at the top and bottom of the wheel rim - tells us the camber.  That is measured in mm but is easy to convert to angle when you know the diameter of the wheel rim (395mm in the case of these 15" wheels).  Each wheel measured 10mm or thereabouts of positive camber.  That equates to 1.45 deg positive camber when it should be +/-  0 to 0.5 of a degree.   Only with my 105kg bulk sitting on the rear wing / on the rear light did we get close to getting the suspension height change to adjust the wheel camber to close to being zero.    

At speed around a corner I'd fall off :help:  so I'll next need to adjust the camber by altering the trailing arm brackets. I'm going to try reversing which way around they are fitted onto the chassis rail. 

That's it. It was time for a quick cuppa tea, and for Mathew to look at some Caterham seats I have, before he headed for home.  

I know what's got to be done. It's a little frustrating that I'm having to do it, but I'm at least of a calm piece of mind to get one with it, possibly over the weekend.

Big Thanks to Mathew for his help, patience, amicable nature and positive motivation. 

He's taking an unscheduled break from jobs right now, and I wish him a speedy recovery. 



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1 hour ago, Bfg said:

That job was just to tighten the central hub assembly nut up to the prescribed 100-110 ft lb.  which with my background in old bikes rather than cars, leaves me a slight disadvantage. To me (having never had a hub apart to see the bearing assembly & inner workings) that big nut appears to be a wheel-bearing nut, which with old cars I thought was "pinched-up tight and backed-off by one flat of the nut"  ..then put the split-pin in and it's good to go. 

Err... no. That nut holds the hub onto the drive shaft, a joint that must carry the full torque of the engine multiplied by the gearing. The wheel bearings are set to the correct end-float using shims.

The centre nut of the front, undriven wheels is, indeed, a wheel bearing nut that you pinch up and back off a tad.

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4 minutes ago, Pete Lewis said:

did you load 150lbs on each seat  as per the TR workshop manual  

or the  toe settings wont be quite right 


yes.,  68 kg., or thereabouts, in night storage heater bricks onto each seat

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Yesterday was interesting, but not as productive as I hoped ..and my back now aches something rotten.   Nevertheless here we go . . .

Ignoring for a moment the ride height, which I hoped might be helped a little, with what I was about to do - the challenge was to adjust the rear wheel's positive camber. 

But firstly, I needed to ascertain where we were at.



^ eight approx 8kg night storage-heater bricks in each seat, half a tank of fuel, the spare wheel and another 15kg of weight in the boot to simulate normal load conditions.

The car is on the level having been rocked and rolled forward.

P1390637s.JPG.c52f784f2d630697444f41d0052b6dbb.JPG    P1390638s.JPG.72cc5f8dd1a737a8abcc390be0b1f87e.JPG

^ The spirit-level is standing on the floor and leaning against the wheel-arch brow, with a piece of wood leaning against it to hold it steady while I measure to the rims top and bottom.  The dimensions recorded (rear LHS) were 46.5mm top and 50.5mm bottom, so the top of the wheel was tilting out (positive camber) closer to the spirit level rather than being upright or slightly tilting in.

I did a scale drawing of this (on the computer in ACAD) and the angle equated to 0.73 degrees (positive). The TR4A workshop manual tells me it should be +/- 0.5 degrees. Personally speaking I would like to see zero to -0.5 degrees negative camber.  In any case the requirement is to alter the positive camber to negative by about 3/4 of a degree (have the wheel sitting vertically when the car is loaded or leaning in by about 3mm difference) or just a little more.   NB. the difference on the rear RHS of the car was the same 5mm / 0.73 degree positive camber.   It's reassuring when both are the same.

Now, working on the rear RHS of the car, only because that was easier in my present working environment, and with the wheel off this is what we see . . .


^ Taking the chassis rail as being level,  you can clearly see how the trailing-arm brackets adjust the camber of the trailing arm and therefore the wheel.  It ought, by the look of things, to be negative camber (top of the wheel tilting in) as the orientation of the brackets are correct for this car.  The camber does go to negative as the suspension is compressed. This is so.. when cornering - it's like putting the tyre at a very slight angle to stop it sliding sideways.  As it is the tyre leans outwards and the so is scrubbed further under the side wall.  This positive camber then is consistent with the car's ride height being more than it should be (the springs are not compressing enough).

Looking on Buckeye Triumph's report on adjusting the camber ;  I read this . . .


This records three different bracket shapes, 1, 2 and 3.  each marked with notches on the top edge.  

Type-1 has the trailing-arm pivot / axis bolt (where the rubber or poly-bush goes) just 3.2mm below the centre of the bracket (between the bracket's two mounting bolts). NB. This type-1 is what I have.. seen to the left of my photo (above). 

Type-2 has its pivot/axis-bolt 9.35mm above the centre of the bracket. This type of bracket is what I have (outboard by the sill) seen to the right in the photo above.

Type-3 bracket doesn't concern me because I don't have those (they're sometimes used on the TR6), but for record their pivot/axis-bolt is some 16.8mm below the centre of the bracket. 

3D-2D means Outside a type-3 bracket with notches Down, used in conjunction with an inside type 2 bracket, also with its notches Down.  In this configuration the camber between the brackets is -4.16 degrees ..which because of the trailing arm's geometry gives -3.3 degree (negative camber) of the wheel. (it say 3.61 degrees in another table). Another row starts with 2U-3U whereby the U signifies that the bracket is orientated with its notches UP.   

Katie  presently had the configuration I've highlighted in blue. 2U-1U ..that is type-2 brackets with their notches facing Up on the outside, and type-1 brackets, also with notches Up on the inside (nearer the centreline of the car).

Editing that table into what is pertinent to me at this time .. insomuch as I only have two type-1 brackets and two type-2 brackets to play with, let's clear all the other permutations away ..and so this is what we see . . .


^ The configuration Katie  has (correct according the manual) is again highlighted in blue.. Outer ; 2 with notches Up, inside type-1 bracket also with notches Up.

I want more negative camber by at least 0.73 of a degree ..and the table says to reverse & invert (in red) the brackets I have. That it says would alter the camber by 0.6 degree which is very close to what I want, and the most these particular brackets will give us.  

However to me it doesn't make sense.  Surely if you rotate the brackets 180 degrees ..the angle between them will be the same.?   (Rich - it's just like rotating a cooling fan around :) )     I wasn't convinced ..but at the same time I remained uncertain, as this report is reputed to be accurate.  Perhaps I was missing something.?  So., I took the brackets off and did what it suggested . . .


^ getting those brackets out is a pain-in-the-arse when you're an old fart working under a car on axle stands.  Firstly the road springs had to be removed to take the pressure off them, so driveshaft inner coupling and damper, then the spring could come out, and the trailing-arm pivot-bolts removed, and then finally the bolts holding the brackets to the chassis rail.  Thankfully the corner triangulation / gusset plates I had added didn't restrict access too much but still it was working blind to get the socket in there.

P1390660s.JPG.221d6b5d112243dcd6a6fbaabd1c3533.JPG      P1390659s.JPG.3d988d5a264d093c72ff3b90b6c34339.JPG

^  brackets off the RHS of the car.  The Left bracket with notch Up is type-1 and from the inside, and the right bracket with notches up is the type-2 (which I'm also indicating with the blue masking tape) and that was next to the sill.  on the table this was designated 2U-1U   

^^ RH piccie shows these reversed and inverted as suggested.  On the table above this designated ID-2D.   Nope., the angle didn't suddenly change as I stepped over them to take a photo from that side.  But as I say, I might have been missing something so I put the car's suspension back together again with the brackets this way around.

I then loaded the car up again and bounced, rocked and rolled it forward to the marked-level ground.  But I do admit that I haven't yet driven the car to re-settle the suspension, but for a quick check I presumed this might give us an indication.

Results ;  that side's wheel has adjusted, in part the suspension appears to have dropped by 10mm (wheel centre to wheel arch) which was much more than was predicted in the Buckeye report. This change is in part due to the pivot axis (although the same 2.08 degree angle) being of a different height (as illustrated below) relative to the chassis rail / the bolts on the brackets . . .


^ Drawn to scale, the brackets -3.2mm (type-1 bracket) or +9.35mm (type-2 bracket) offset relative to the chassis rail / the mid axis of the bolts through those brackets.  

Top is how the car's RHS trailing arm brackets were. And across the bottom is how they now are.  And yes as I thought, the pivot's axis angle is unchanged (at 2.08 degrees) and the height relative to the bolt's horizontal axis is lower (by some 6mm).  According to the report this height change should have rotated the wheel, around the spring by " 10.5"/19" or 55% of the change in the bush axis height" ..which translates as lowering the ride height by 55% of 6mm = a little more than 3mm.   For whatever reason my quick check suggests its lowered by around 10mm.   And this is with the M&T supplied replacement road-spring fitted. 

The camber angle did not change by 0.6 degrees, as the table suggests (..so I've not yet gone completely nuts !) but it does appear to altered by almost 1/4 of a degree ..from 0.73 degree of positive camber to 0.51 of positive camber.  Because the angle between brackets has not changed - I might only attribute this change to ; 1. the camber changing according to suspension compression (ride height), and 2. because each of the bracket bolts have been pinched up but not tightened yet, so they have self adjusted with the bushes now being in line and also with any slight slack in the chassis or bracket's holes.

The looseness of fastenings, until the road-spring was refitted, probably also accounts for the noted change in ride height.

- - -

So that's about it.  I think to further correct the camber, I'll need to buy two more type-2 brackets, and to swap them out for the type-1's that are fitted.  This ought to alter the angle between the brackets by almost exactly 1 degree, which will translate through the geometry (according to that report) to -0.87 degree of the wheel.  That would take the present 0.51 deg positive to -0.36 (negative) camber ..which is exactly what I want.   However the ride height will go back up again be 3 or 4mm. 

I think only shorter / lowered springs, or less than 7mm thick collars, is going to help with that.  



^ Interestingly, or not, from photos taken when I was first looking around under this car.., the brackets this way up (now inverted) are close to what we had before the chassis change. . . particularly evident with the inside bracket (top left in this photo) whose the bottom edge is almost parallel with the bottom of the adjacent chassis leg.

I'm particularly grateful to the gentlemen who wrote the article for Buckeye Triumph  as, although their data is in some parts wrong, they have provided a lot of useful measurements and an overall well-worthwhile insight into the geometry of these IRS components.  BIG THANK YOU to them. 



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Just a thought. When you make the same adjustment to the LHS side of the car, lowering that side down by an equivalent amount should also reduce the apparent positive camber on the RHS? Assuming you're measuring only the wheel against the vertical?


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  • 3 weeks later...

Good point Gully,

I was struggling to understand why the measured change in ride height and camber was not closer to that predicted in the Buckeye-Triumph reports. 

Dwelling on the issue and work the car came to a halt with my having to prepare for having a minor operation.  I live alone, so things like grocery shopping and house cleaning, bedding, car insurance and other bills, as well as positioning of furniture as zimmer-frame like aides to getting up n’ down etc., all had to be done / dealt with in advance of my being laid up thereafter. Then last Tuesday I was surprised to wake up from having open-surgery rather than key-hole as expected.  Anyway, right now I'm on the mend again, but off physical bending, stretching & lifting exertions, including jacking up the car, crawling under it, undoing and lifting off a wheel, &/or reaching and struggling to loosen half-shaft and trailing-arm bolts. 

I hope to get back on with it soon but in the meantime, when able to concentrate, I've been looking again at the Buckeye-Triumph reports.  I've found a number of errors in their figures. Their author’s thinking of what happens when adjustments are made has been really helpful, but in practice their measurements were a little off.  Tbh., not enough in themselves to make a significant difference but possibly enough to confuse the issue ..of why actual adjustments don't result according to prediction.

However, your point of my adjusting just one side and then re-measuring the effects ..on car now leaning, is inspired. Thank you.

TBh., I really didn't think it would make much difference over the full width of the car (the axle's track dimension), but I've just checked.. and just 10mm lower suspension on one side, on the TR4's track width of 48.5" (1233mm), equates to the car leaning by almost half a degree (0.465 deg).  This of course means the chassis, the trailing-arm brackets, and therefore the wheel-bearing's hub, being likewise tilted relative to the datum vertical spirit-level.  

Should anyone be looking at the same issues, of ride height &/or the rear wheel’s camber being out - In due course I’ll try to pull together a few more pointers.


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Hi Pete,

 don't know what surgery you have had but do take it steady. With the years ticking on recovery does take its time.

No point in putting back the recovery rate just to get the car sorted quicker than is needed.

Look after your self.



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1 minute ago, RogerH said:

Hi Pete,

 don't know what surgery you have had but do take it steady. With the years ticking on recovery does take its time.

No point in putting back the recovery rate just to get the car sorted quicker than is needed.

Look after your self.



Second that. Get yourself fit first, the car will come.

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3 hours ago, Mathew said:

Second that. Get yourself fit first, the car will come.

Yep - definitely make sure to give yourself time and space to heal well. The car isn’t going anywhere while you rest.

........ Andy

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On 20/09/2021 at 17:59, Bfg said:

P1390660s.JPG.221d6b5d112243dcd6a6fbaabd1c3533.JPG      P1390659s.JPG.3d988d5a264d093c72ff3b90b6c34339.JPG

Just a small point / thought - can you get full-length bolts for these, where the bracket rests on the collar and not the threaded section? When I was rebuilding the TR7 the kit came with bolts that were to me unsuitable, the threaded section was through the bracket itself and I was concerned about rapid wear, so I sourced longer that were a more correct-looking fit.

DSCF7152.jpg.12b0186b8976bf972d14f1e9c35883d9.jpg  DSCF7164.jpg.925a99e60d504627c269b4da3d226f5e.jpg


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just make sure it clamps the crush tube firmly and the nut doesnt  bottom  out  the bolt should not rotate in use.

the bush should rotate around the tube firmly clamped between the ears of the bracket 

and yes get well soon     too many of us are on the ailing creak and groan listing 


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