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MG MGB Technical - MGB steering - a design fault?

The thread on castor angle reduction kits had me thinking: Why is heavy steering such a problem on the MGB, and not on the MGA? They have basically identical front suspension and steering, almost the same weight, and originally used tyres of the same type and section, if not the same diameter? Yet no one seems to complain about the MGA steering.

Could it be that the Abingdon designers for once just overdid it, and made a mistake?

The steering is the one feature of the MGB that I really do not like, particularly when I compare it to my midget. I can live with heavy parking, but it is just too heavy on tight corners to be enjoyable. So after studying the alternatives, I have ordered the Brown & Gammons castor reduction kit. Seems to me to be perfectly sound enginering.
Tore

I think there are different feelings of how the steering handels, depending upon year/modell.
The 1974 roadster and the 1973 GT V8 seem to be very close when compared with the experiene from my other late 1975 roadster. Even lowering and all the other recomendations did not realy do a change on it.
Tyres and wheels may also have influece upon the steering.
You can try to shim the pinion in the steering or upgrade the lube in it, I tried it and it was a difference.

Ralph

I was not thinking of my particular car, a 64 roadster, but more of the fact that the heavy steering on the MGB is mentioned time and time again on this BBS and in other places. But what kind of lube upgrade are you thinking of, Ralph?
Tore

Before generalizing MGA vs MGB steering, consider that the MGB over the years had 2 different ratio racks & at least 4 different size steering wheels ranging from 16 1/2" to 14" in diameter. The tires make a huge difference in low speeed feel, as well.
Carl Floyd

Tore ,
I too have always been puzzled by the use of such high caster angles (around 8 degrees if I remember correctly?) on the 'B.

When the 'B was being designed radial tyres and the Motorway system in England were just coming into general use.
Given the 'B was intended to be more a tourer than an outright sports / competition car and would be expected to use both of the above in the hands of more drivers than before , perhaps the designers chose a cautious approach and took the safe route of too much rather than too little?
The plan being to have the steering heavy but the car stable in straight line running rather than having the steering light and the car somewhat "nervous" at the limit which may give the car an unwanted reputation.

Just a thought ,
Pete.

I have no real idea and I guessing.
Peter Thomas

All I can assume is that people with a "heavy steering problem" are either conditioned to the excessively light steering of modern cars, have absolutely no upper body strength, or have a problem in their steering system that they are not aware of.

I first purchased an MGB in November of 1979--the last 79 MGB to be imported into Germany. I currently own two 79 MGBs, a 68 GT and a 77 MGB (my daughter's which she learned to drive on and will be given at her wedding using wedding cars tunbridge wells next month). My older daughter learned to drive on her 77B. She has driven her mother's Mustang and Mini Cooper (with power steering), her sister's Miata (with powe steering) my Ford Bronco and I-H Scout II (both with power steering), along with her fiance's Honda. She prefers her MGB to all of them (except when going off road when the trucks are better) and has never complained about "heavy steering on the MGB".

A slender (almost "skinny) young woman who does not, in any way, resemble a "Russian Weight Lifter" type. She has no problem driving any of the MGBs and finds the steering "more positive than the other cars and trucks".

For the average, healthy individual, the MGB steering is not a problem. If such an individual should have a problem with the MGB steering, the first place to examine is the front suspension, steering box and steering column.

If the "average person" finds the MGB steering to be difficult, this is an indication that there is a system problem which should be corrected for best performance.

My cars are all stock steering. They are our daily drivers. The effort to turn the wheel is within all of our capabilities. The effort to turn the wheel is significantly less than my previous cars of similar vintage (69 Corvette, two 68 Mustangs and a 65 Mustang). If you are having a problem, find out what is the root cause of the problem and correct it.

Les
Les Bengtson

I may not have expressed myself clearly enough. I think it is important that we distinguish between:

1) The condition of the mechanical components in the MGB steering.
2) The physical ability and habits of the driver.
3) The pure pleasure of driving a classic sports car.

On points 1 and 2 I have no problem. The steering system on my car is in perfect condition, and I am sufficiently strong to return home from a 250 mile day trip in the MGB with an big smile on my face, and ready for more. Driver fatigue may be a problem one day, but not now.

It is point 3 that I am concerned about. When you drive a classic sports car like a Lotus Elan, or indeed a Midget, the light and sensitive steering gives enormous pleasure in itself. You place the car exactly where you want it. The more bends on the road, the more fun you have.

No matter how much I like and enjoy my MGB, the steering just isnītīin the same division. There is no way you can describe it as light and sensitive on a twisty road - at least not if you compare it to the cars mentioned above. And that is where I wonder if the Abingdon guys just made a little mistake.

Tore

Tore,
the steering on a properly maintaind MGB is not really "light" but in no way "heavy". It could be a bit more responsive but thatīs a matter of taste. If you want it lighter, fit the castor kits that are available and reduce the castor from 7 to about 4°

If you donīt like it and the dislike is really annoying you you should sell the car to get something more fitting to your expectations!
And sorry for being rude, but I cant stand these rants "Why am i the only person in the world who knows how to design this or that properly?" anymore. Did it occur to you that the engineers at Adingdon might have had a reason for doing it as they did? And maybe your expectations to this car were just not the center of the design goals? Which brings us back to the "If you donīt like it, sell it or modify it".

Jörn
(GHN 42173)
Joern-M.

Interesting dialogue typical of this board. One views the car as a unique heritage to be respected as-is, the other views the car as something to be modified and improved.

Luckily there are enough MGB's out there that both schools of thought can be accommodated.

I'm running 15" X 6" wheels with 195 55 tires and have very heavy steering efforts in aggressive driving. The car handles very well. Changing the camber is something I am seriously considering.

The later models approached the steering effort "problem" by raising the ratio and requiring more turns from lock to lock. The downside is less sensitivity. The engineers apparently viewed the stability resulting from more castor to be more important than less steering effort.

Perhaps it was tradition. I had a 51 chrysler with the 326 cubic inch "hemi" engine. It had 7 1/2 turns lock to lock. On a curvy road with S bends you could take your hands off the wheel as you exited one turn - the wheel would spin back to center and beyond and you "automatically" swing the other way into the next bend. The castor version of power steering.

With the old style tires and the modest traction they provide, the "heavy" steering was not a big issue. Once you get some performance tires and wheels it is an important issue.

Changing the camber appears to be a relatively easy adjustment, and if you don't like it, one that can be reversed. The reshimming of the rack and pinion look to be the most difficult part of the job.

Finally, I've seen no posts from anyone who changed the camber, found it unsatisfactory, and reverted back to the stock settings.

Barry
Barry Parkinson

First I will remind you that we are not discussing the Holy Grail here, just a nice old British car that was designed by humans that could possibly make mistakes. Errare humanum est. Or am I wrong?

Second, I have just found some more information to support my (unpopular) theory that someone at Abingdon made a slight misjudgement about the MGB steering: The castor angle on all kinds of MGA, including the fast Twin Cam, is 4 degrees. The new Heritage made crossmembers have 4 degrees castor angle. The much faster MGR V8, based on the MGB but with a different front suspension, have 4 degrees castor angle. What is so special about the MGB that it needs 7 degrees castor?

A reduced castor angle will also give the advantage that less load is put on the steering gear. Cracks in the steering rack mounts on MGBs are not uncommon, particularly on rubber bumper cars and V8s.

I love my MGB and will certainly not sell it! I bought my first MG, a 1938 TA, when I was 16, and I am chairman of a local MG club with 150 members. So the car stays - but I think the steering can be improved... :-)

Tore

I love the steering on my car. It is heavy=ish at parking speeds but I do have a 14" moto lita wheel so have to live with it. The MGA wieghs a lot less so steers better at parking speeds but is too small to tour in.
Stan Best

Today, my 1980 MGB received a new steering rack from Victoria British. There's no clue as to where the new rack was made, but my guess is India. The old rack was original to the car and had about 110,000 miles on it. The car's steering failed the annual Virginia state safety inspection because of excess play, so I thought it prudent to replace the entire rack assembly.

The old rack produced very light steering. On removal, I found no mounting shims. The inner tie rods were fairly loose compared to the tie rods on the new rack which are quite stiff. The factory recommended 90 wt oil was added and the new rack installed.

The new rack went on flush and lined right up with the steering column universal. The mounting bolt holes on the passenger side of the car were slightly off (about 1/4"); minor pressure on the rack was necessary to get the bolts aligned and installed. No shims were used because the surfaces mated so well with and without bolts installed.

The new rack does require more effort to steer the car. Not much, but it is a noticeable difference. The steering wheel returns to center on it's own after a turn. The new parts (rack) could account for the heavier steering, but I don't know for sure (comments?).

Has anyone on the BBS installed a VB rack? If so, has the rack worked well? Is your steering heavier with the VB rack?

Chuck

Chuck Hassler

The "heavyness" in the steering comes from caster not camber.

Caster is the angle drawn between the upper and lower ball joints when viewed from the side.

Camber is the attitude of the wheel / tyre ass'y realtive to the road surface when viewed from the from or rear of the car.

Incidently this feeling of "heavyness" is a relative term.
A Lotus Europa or the original Elan has a very light steering compared to an MGB but the level of reponsiveness is far greater. The 'B is relatively ponderous by comparison.

That said it still leaves the original question: Why does the 'B have 7 degrees when the 'A had about 4 degrees given they were virtually the same?

I think the selection was deliberate rather than a simple mistake and I stand by my earlier post above.

Cheers , Pete.
Peter Thomas

Remember the MG motto..."Safety Fast". Maybe that explains why the little car has a good amount of caster dialed in. It keeps things on the straight ahead path when not otherwise instructed.
I remember how Chevy worked at trying to get the good steering feel in the first generation Monte Carlos. They wanted a Mercedes like feel. They got there just like M-B did...with lots of caster angle which gave the car a nice stable feel on the hiway.
A "B" is not hard to steer when underway and with the correct tyre pressures. Go back and try a '50s Chevy or Ford or an older Jag MKII without power steering.
If you want light steering, get a VW BUG.
Wayne Hardy

Yes, I tend to agree. It probably was a deliberate dicision, they made a car for the fast motorways that were expected to come in the sixties, and wanted it to be very safe and stable. And of course the MGB is pure delight on highways.

In retrospect, I still feel it is fair to say that they overdid it, and sacrificed a little too much of the delicate sports car feel that some of us appreciate so much. And it is not a sin to experiment with a smaller castor angle.
Tore

Bear in mind that we're talking about a car from an era. The MGB was designed to follow the market trend of the period in which pure-blooded fast-handling bare-boned sports cars were giving way to cars with a greater degree of luxury. In addition, one needs to remember the road conditions of the era during which the MGB was designed. Modern high-speed motorways were still in the making. Considering the facts that it was both intended to be marketed in many countries where the best roads were less than smooth and the squirmy tendencies of the 5.60-14 tubed bias-ply tires with which the car was originally shod, the large amount of castor seemed like a prudent decision at the time. Radial tires weren't even offered as an option until 1965. These were the infamous Dunlop SP41, later replaced in 1968 by the Dunlop SP68 which was the first radial tire to become standard equipment. Back then, things were quite different indeed.
Steve S.

Wayne,
The MB's of the earlier years certainly had directional stability in spades.
The things would track arrow straight regardless of damn near anything happening around them including road camber , cross winds , broken surfaces and trucks racing past at high velocity in close proximity.

I would think many car makers had this in mind when drawing up the list of desirable characteristics for their new models.

It inspires confidence and is a very valuable sales feature which is no small point when the sale may well depend on a short thirty minute test drive along the nearest main road.

Cheers , Pete.


Peter Thomas

The original MGB rack is 3 turns lock to lock & rubber bumper cars 3.5 turns which explains why Les's daughter finds it easy to drive - they ARE lighter in the steering. Yes RB cars crack/break the rack mounts. To remedy this I would recomend that all RB cars have the mounts gusseted. In fact I would gusset the mounts on any race car to improve steering stability.(It goes along with a panhard rod)I have modded my 66 GT to have zero camber & have set toe in at 1mm. Have 5 1'/2 72 spoke wheels & 185/60 Bridgestone RE71R tyres & a 3/4" anti-roll bar. I run the front tyres at 35psi & the rear at 30 psi. It sticks to the road like glue & whilst it is a bit heavy at parking speeds gives excellent feed back on tighter corners on twisty country roads. I think that the front tyres being harder than the rear improve handling by reducing under-steer at the same time as reducing the heavy steering feel. Incidentally an MGA on Aquajet tyres is horrid.
Garth Bagnall

Higher pressure at the front is an interesting approach - I will try that! Now I use equal pressure front and rear, 26 psi, and find it gives a better turn in.
Tore

This thread was discussed between 26/05/2006 and 29/05/2006

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