The Triumph Dolomite Club - Discussion Forum

SprintV8 wrote: ↑Mon Jan 24, 2022 10:21 am

Boost All The Dollys wrote: ↑Mon Jan 24, 2022 9:44 am
You mean the lower ball joint mount? Are these known for flexing or breaking? I’ll definitely consider it.

And I’d more than likely copy it so it’s a drop in part. I have looked at the triumph suspension to find out camber curves and caster angles but haven’t looked at bump steer yet as I haven’t had the time to model up the steering rack and subframe fully yet, I just have a half-ok representation of the suspension mounts and arms.

And this would be a direct replacement for the stock triumph upright. Which can be used with the Sprintspeed stub axles to use a Ford Escort RS hub, either alloy or iron. And I’d never heard of a larger bearing stub axle available for the Dolomite till someone here mentioned it so if the GT6 one works, I’d go with their knowledge and judgement. And seeing as the ST parts for the triumph seems to be just parts off other triumphs, I’d guess that it’s likely that the better hub axles would be GT6

Yes I meant the Lower Ball Joint/Steering arm.
I haven’t heard of any breaking.

It just looks like you need more support around these points.

Billet alloy would be the best and strongest to machine from but not the cheapest.
Are you machining the final part.

Depends on need I guess. If more people wanted them, can look around and price up billets but for prototypes and for a one off, I was going with a fabricated design so only a few small pieces would be machined, such as the centre taper bore and the upper ball joint taper as getting them knocked out on a lathe would be much cheaper/easier than getting the full thing milled.

And to be honest, the strength difference between them, all other things being equal, would be marginal. If you wanted the lightest possible uprights which had only as much strength as necessary, billet would be the way to go, but that would cost a good bit compared to a fabricated set which should work to the same strength as factory.

And as this is all for weight saving anyway, I’m trying to take as much out anyway, such as making the uprights handed so the disc shield mounts aren’t the same strength as the brake callipers mounts.

As much as I’m in awe of the engineering that went into the dolomites suspension, from a design-vs-cost standpoint, it’s left a whole football field sized area for improvements on the table. Things like:

• the uprights aren’t handed so you only need one tooling

• the 3-piece upper arms so you only need 2 sets of tooling

• make 4-5 different cars using the same basic structural design for 15 years but allows for RWD, FWD, AND AWD

And that’s my end goal for my car at least, find where the bean-counters prevented development and go as far as I can without resorting to remortgages or making a Dolomite not a Dolomite anymore. Kind of like the Alfaholics GTA 290, but I’m skipping on trying the engine side haha

SprintV8 wrote: ↑Mon Jan 24, 2022 6:22 am Your going to need to beef up the steering arm mounting points.
I know is only a drawing at this stage it is in need of much more strengthening.

Providing you copy the original mounting points and location of the original vertical upright.
There shouldn’t be any issues with bump steer ETC unless Triumph got it wrong to start with.


Large stub axle.
What are you guys using and from where.
Are these for Escort or Triumph hubs.

My hubs and stub axle come from CDD Classic Driving Development mine are for a Stag,but Sprint Speed also sell the allyo hub for the Dolomite

new to this wrote: ↑Mon Jan 24, 2022 7:01 pm

SprintV8 wrote: ↑Mon Jan 24, 2022 6:22 am Your going to need to beef up the steering arm mounting points.
I know is only a drawing at this stage it is in need of much more strengthening.

Providing you copy the original mounting points and location of the original vertical upright.
There shouldn’t be any issues with bump steer ETC unless Triumph got it wrong to start with.


Large stub axle.
What are you guys using and from where.
Are these for Escort or Triumph hubs.

My hubs and stub axle come from CDD Classic Driving Development mine are for a Stag,but Sprint Speed also sell the allyo hub for the Dolomite

Ahh, fair enough, I did think they might use Stag/T2000 as I think the ST lower arms are T2000 as well.

And Sprintspeed sell an alloy rear hub which also changes the PCD to Ford pattern, and their alloy front hubs is just a stub axle which lets you use the Ford Escort alloy hubs

I’m already using the Stag Spindles.

May be a worth wilde upgrade once she’s up and running and done a few miles.

The GT6 wheel bearings are the same part numbers as the Dolomite ones, so I doubt the GT6 stub axle is much different.

The uprated stub axle allows for 2 identical larger bearings to be fitted (note in pics the uprated stub is parallel sided and the stock one is tapered) the tiny outer bearing on the stock Dolomite stub is a known weakness for "heavy duty" use.

I wouldn't use an alloy vertical link if I could get one. I just don't think it would be strong enough unless you added a lot of extra mass to it. Which would negate the purpose of making it lighter. TBH, I also wouldn't want to trust my neck to a home made version of such a safety critical item! Especially when the standard steel one is good enough. I also don't think the original is that heavy, I strongly doubt it's over 2kg (link and stub together, but without hub and bearings) I've got a few around here, i'll weigh one tomorrow on SWMBO's kitchen scales!

It takes me around 30 secs to chop an "ear" off a stock link for TJs, where's the problem?

Steve

Carledo wrote: ↑Mon Jan 24, 2022 9:01 pm
I wouldn't use an alloy vertical link if I could get one. I just don't think it would be strong enough unless you added a lot of extra mass to it. Which would negate the purpose of making it lighter. TBH, I also wouldn't want to trust my neck to a home made version of such a safety critical item! Especially when the standard steel one is good enough.
Steve

My thoughts too its just not worth the risk, worse case would be appearing in court to explain the death of another person because you wanted to save 1kg in weight

Carledo wrote: ↑Mon Jan 24, 2022 9:01 pm The GT6 wheel bearings are the same part numbers as the Dolomite ones, so I doubt the GT6 stub axle is much different.

The uprated stub axle allows for 2 identical larger bearings to be fitted (note in pics the uprated stub is parallel sided and the stock one is tapered) the tiny outer bearing on the stock Dolomite stub is a known weakness for "heavy duty" use.

I wouldn't use an alloy vertical link if I could get one. I just don't think it would be strong enough unless you added a lot of extra mass to it. Which would negate the purpose of making it lighter. TBH, I also wouldn't want to trust my neck to a home made version of such a safety critical item! Especially when the standard steel one is good enough. I also don't think the original is that heavy, I strongly doubt it's over 2kg (link and stub together, but without hub and bearings) I've got a few around here, i'll weigh one tomorrow on SWMBO's kitchen scales!

It takes me around 30 secs to chop an "ear" off a stock link for TJs, where's the problem?

Steve

You can cut the ear of the stock link, and pick up a new mounting point for the Disc back plate from the TJ mounting brackets,but you will need to make new disc back plates ive got a template from the one i made

new to this wrote: ↑Mon Jan 24, 2022 9:26 pm

Carledo wrote: ↑Mon Jan 24, 2022 9:01 pm The GT6 wheel bearings are the same part numbers as the Dolomite ones, so I doubt the GT6 stub axle is much different.

The uprated stub axle allows for 2 identical larger bearings to be fitted (note in pics the uprated stub is parallel sided and the stock one is tapered) the tiny outer bearing on the stock Dolomite stub is a known weakness for "heavy duty" use.

I wouldn't use an alloy vertical link if I could get one. I just don't think it would be strong enough unless you added a lot of extra mass to it. Which would negate the purpose of making it lighter. TBH, I also wouldn't want to trust my neck to a home made version of such a safety critical item! Especially when the standard steel one is good enough. I also don't think the original is that heavy, I strongly doubt it's over 2kg (link and stub together, but without hub and bearings) I've got a few around here, i'll weigh one tomorrow on SWMBO's kitchen scales!

It takes me around 30 secs to chop an "ear" off a stock link for TJs, where's the problem?

Steve

You can cut the ear of the stock link, and pick up a new mounting point for the Disc back plate from the TJ mounting brackets,but you will need to make new disc back plates ive got a template from the one i made

I just run without backplates, had no issues so far in more than 10 years. Though I do keep the little bottom one to heatshield the balljoint, just bend it a bit!

Steve

2.5KG Vertical upright with Stag spindle and a few bolts.

SprintV8 wrote: ↑Mon Jan 24, 2022 10:23 pm 2.5KG Vertical upright with Stag spindle and a few bolts.

I take it Mrs Reader was out this evening!

TrustNo1 wrote: ↑Mon Jan 24, 2022 9:07 pm

Carledo wrote: ↑Mon Jan 24, 2022 9:01 pm
I wouldn't use an alloy vertical link if I could get one. I just don't think it would be strong enough unless you added a lot of extra mass to it. Which would negate the purpose of making it lighter. TBH, I also wouldn't want to trust my neck to a home made version of such a safety critical item! Especially when the standard steel one is good enough.
Steve

My thoughts too its just not worth the risk, worse case would be appearing in court to explain the death of another person because you wanted to save 1kg in weight

That was my opening response!

The GT6 wheel bearings are the same part numbers as the Dolomite ones, so I doubt the GT6 stub axle is much different.

I recall something in the back of my mind that they're similar, but longer...

xvivalve wrote: ↑Mon Jan 24, 2022 11:13 pm

The GT6 wheel bearings are the same part numbers as the Dolomite ones, so I doubt the GT6 stub axle is much different.

I recall something in the back of my mind that they're similar, but longer...

Stag spindles are slightly longer.

Mrs R was at home this evening,
Good job as this was done earlier in the day.

Carledo wrote: ↑Mon Jan 24, 2022 9:01 pm The GT6 wheel bearings are the same part numbers as the Dolomite ones, so I doubt the GT6 stub axle is much different.

The uprated stub axle allows for 2 identical larger bearings to be fitted (note in pics the uprated stub is parallel sided and the stock one is tapered) the tiny outer bearing on the stock Dolomite stub is a known weakness for "heavy duty" use.

I wouldn't use an alloy vertical link if I could get one. I just don't think it would be strong enough unless you added a lot of extra mass to it. Which would negate the purpose of making it lighter. TBH, I also wouldn't want to trust my neck to a home made version of such a safety critical item! Especially when the standard steel one is good enough. I also don't think the original is that heavy, I strongly doubt it's over 2kg (link and stub together, but without hub and bearings) I've got a few around here, i'll weigh one tomorrow on SWMBO's kitchen scales!

It takes me around 30 secs to chop an "ear" off a stock link for TJs, where's the problem?

Steve

Well, aluminium is 1/2 the weight, 2/3 the strength, so you need 4/3rds the thickness for equivalent strength, which works out about a 1/3 weight loss everything being equal.

And yes, that’s why I’d never consider selling them or anything, I don’t want that liability hanging over my head, where as I’m more than happy to make my own set and put myself at risk. These would pretty much be a track only part, as I doubt it would benefit anyone off track.

Boost All The Dollys wrote: ↑Sat Jan 29, 2022 7:55 pm

Well, aluminium is 1/2 the weight, 2/3 the strength, so you need 4/3rds the thickness for equivalent strength, which works out about a 1/3 weight loss everything being equal.

Making it thicker doesn't always mean you are making it stronger.