Rear Anti Roll Bar

[Boost All The Dollys]

Hey guys

I've recently bought a rear anti roll bar as my 1500 wasn't fitted with one from the factory, read on here a while back that it may not help with handling, is that true? Something to do with the race teams removing them if they could?
Thanks
Max

[Magenta Auto Sprint]

they may remove them to save weight or it could be that race cars have different handling requirements/characteristics.

I fitted a ARB to my 1300, I think it is better, also I am sure if they added nothing then the BL bean counters would not have fitted them to save a few quid. Also later ARBs were thicker, why was that I wonder.

malcolm

[Boost All The Dollys]

they may remove them to save weight or it could be that race cars have different handling requirements/characteristics.

I fitted a ARB to my 1300, I think it is better, also I am sure if they added nothing then the BL bean counters would not have fitted them to save a few quid. Also later ARBs were thicker, why was that I wonder.

malcolm

Cheers Malcolm

[Richard the old one]

I had one fitted to one of my 1500HLs for a number of years but I have recently taken it off because I found that it had been rubbing on the propshaft. I am assuming that this only happened when I had a heavy load such as three in the back or went over speed bumps. I did not notice any difference in handling.

[Carledo]

Unless you are driving on or close to the limit (and i'm not discussing a speed limit here) a rear ARB makes little difference.

On a standard car, (Sprint or 1850) the rear bar is there to promote understeer under normal fast road conditions. Your original 1500 didn't have one for the simple reason that it wasn't considered powerful enough to need help controlling oversteer!

The race boys in the 70s deleted the rear bar (or replaced it with a bit of wire for homologation purposes) because they WANTED the cars to oversteer more!

You are now messing about with power output, weight distribution, spring rates, shox, geometry, etc, all of which have only semi predictable effects on handling. My advice to you is to try it both ways and see which YOU prefer! On the limit handling is very subjective, what suits you may not suit me and vice-versa. I've fitted and kept a rear bar on the Carledo because I prefer it with one. But I am not you, and the Carledo with its Vauxhall powerplant and only 2 doors is not even similar in setup to your 4 door Dolomite body. There is NO recieved wisdom here, it's all down to personal preference. And it's not exactly difficult or time consuming to remove it/refit it to try both choices! But leave the trial until you have finalised the rest of the suspension setup!

Steve

[trackerjack]

What he said
I do not always think that the makers of cars are right all the time and we drivers are different too. They make cars as safe as they can assuming a driver to be the worst case possible which is why they set all cars up to understeer so when an idiot charges into a corner too fast and lifts off the power the car does not oversteer off into the scenery, but the driver who want to induce oversteer can do so and return to power to stabilize the situation.
Hence people will come onto forums spouting standard only and the engineers knew how to make cars best and who are to say they know better than a professional auto engineer.
I took my rear ARB off my car which was a lightly modified Sprint.

[gmsclassics]

Both my road Sprints, with standard suspension and steering geometry, have the factory rear roll bar fitted and they handle superbly on the road.

The race car doesn't have one fitted as that gives the most stable cornering, on the track and on the limit. However, there is nothing standard about the tyres, steering geometry, suspension rates, front roll bar, or engine power and torque.

Suggest you ignore anything you've been told about race setup and either stick to the original setup or what others have used on their road cars. However if you make any changes to factory setup, watch for handling changes in the more challenging circumstances, such as wet, bumpy or uneven surfaces, especially when cornering or braking. As others have said, it will mostly depend on how YOU drive and what YOU prefer.

I once tried fitting a stiffer than normal rear rollbar to the rear of the race Sprint but had to take it off after only one race as it provoked so much over-steer that I couldn't keep it facing the right way on almost all of the fast sweeping corners!

Geoff

[Jon Tilson]

For what its worth I fitted one to my slightly uprated 1300 which I sold a good while ago now....

Car seems still to be around and sold again quite recently, but I digress....but at least none of its young blade owners stacked it.

I thought it was a major improvement and it felt much more secure and predictable on wet roundabouts for example.

Car was on standard 155-80 tyres and decent munroe rear shocks.

Jonners

[naskeet]

Unless you are driving on or close to the limit (and i'm not discussing a speed limit here) a rear ARB makes little difference.

On a standard car, (Sprint or 1850) the rear bar is there to promote understeer under normal fast road conditions. Your original 1500 didn't have one for the simple reason that it wasn't considered powerful enough to need help controlling oversteer!

The race boys in the 70s deleted the rear bar (or replaced it with a bit of wire for homologation purposes) because they WANTED the cars to oversteer more!

You are now messing about with power output, weight distribution, spring rates, shox, geometry, etc, all of which have only semi predictable effects on handling. My advice to you is to try it both ways and see which YOU prefer! On the limit handling is very subjective, what suits you may not suit me and vice-versa. I've fitted and kept a rear bar on the Carledo because I prefer it with one. But I am not you, and the Carledo with its Vauxhall powerplant and only 2 doors is not even similar in setup to your 4 door Dolomite body. There is NO recieved wisdom here, it's all down to personal preference. And it's not exactly difficult or time consuming to remove it/refit it to try both choices! But leave the trial until you have finalised the rest of the suspension setup!

Steve

From what I have generally read about understeer and oversteer characteristics, DECREASING the stiffness of a FRONT anti-roll bar and/or INCREASING the stiffness of REAR anti-roll bar, has the effect of INCREASING oversteer or DECREASING understeer!?!

That said, when I retro-fitted just a Dolomite Sprint rear anti-roll bar to my 1974 Triumph Toledo 1300 (Cosmic alloy wheels, with 21 mm offset and 175 SR13 Kelly-Springfield tyres), I did not notice any adverse affects on the steering characteristics when negotiating tight bends. I later retro-fitted a Dolomite Sprint front anti-roll bar and decambered the front wheels by removing the upper wishbone-bracket spacers; again with no adverse affects on the steering characteristics or tyre wear.