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MG MGB Technical - Front suspension castor angles

Has anyone any experience of fitting the Frontline castor angle wedges, these are supposed to lighten the steering, but there seems to be an element of doubt expressed in certain quarters.
They are very expensive for what they are, I know that commercial factors apply, any thoughts or comments would be appreciated.
regards
Trevor Jones
trevor jones

Hi Trevor

I am waiting for the Brown & Gammons castor kit to arrive. It is considerably cheaper than the front line kit but maybe a little more difficult to fit. I shall keep you informes as to the results.

Carl
C Bintcliffe

Hi Trevor ,
I use a Frontline Castor Adjuster and it works beautifully ,easy to install and it makes the steering much lighter above walking speed with negative camber suspension in a v8 Rover engine Roadster. It does what is says on the Tin!! Best £80 I have spent on the car
Regards
Andy
ap lestocq

Hello,

Thanks for this info. But how did you achieve the column realignement after setting up this castor kit?
Regards.
Renou

Hello Guys
Thanks for the feed back, the things that concern me regarding the Frontline product, are lack of positive location to prevent the wedge from squeezing outthrough the torque reaction, between the chassis members, the rubber insulation block and the cross member, and the fact it is in ali which will cause corrosion,
I will hang on a little while until B & G come up with their answer,I have emailed them but had no response as yet.
Thank you again a solution to the steering load up is definitely needed.
Regards
Trevor
trevor jones

"much lighter above walking speed"

That's what I suspected. Some help with parking, but not when you are swapping locks at a standstill i.e. parallel parking.
Paul Hunt 2

I can live with the heavy static steering, it is the just above walking pace speeds that I have a problem with. I had a phone call from Brown & Gammons today explaining that they are having a problem with there e-mails. There is a slight delay at the moment with the castor kit but they have promised me that it will be with me soon.

Trevor It may be worth giving them a ring.

I shall let you know how it goes once I have fitted the kit.

Cheers Carl
C Bintcliffe

I fitted Frontline to a 69 Roadster. Doesn't seem to make much diffrence. Roger Parker MGOC reckoned more use on RV8s

Michael
Michael Beswick

As far as I am aware, the RV8 already had the castor reduced, so using a kit on that would be dangerous, if I'm right. I have put the B&G kit on my car, but I haven't driven it yet as the car is in bits. But the kit is a much better item than the wedges in my opinion. It is properly thought out and allows complete location of the pads over their whole surface, which the forked wedge can't allow. The kit also contains shims to bring the steering rack back in line.
Mike Howlett

Trevor,

This may be of use to you if you have already seen it:

http://www.v8register.net/subpages/RV8NOTE232.htm

Tore
Tore

If you have NOT already seen it, that is...

Have a look at this, too:

http://www.v8register.net/subpages/RV8NOTE231.htm

Tore

Are you sure that the steering rack, suspension and tyres are all in good shape? I have just rebuild my 67 BGT suspension and the steering is light when the car moves. Perhaps the tracking needs adjusted if you have heavy steering, or the tyre pressures need raised a touch? An MGB with bits in good condition should not need lighter steering unless there is a physical reason, in which case it may be worth considering going the whole hog and fitting power steering (not cheap mind!)

Iain
67 BGT
I D Cameron

Thanks very much for that Tore, I look foreward to feeling the differance when I fit my B&G kit.

Carl
C Bintcliffe

Thanks everyone for your imput, Iain I the main problem is that the steering loads up the more you turn particularly at higher speeds, which detracts from the car, the MGA does not do this which is interesting as the suspension is basically the same.
Tore I had notseen the V8 notes my car is an early V8 GT.

The B & G system is better thought out in my opinion.
Regards Trevor
trevor jones

Hi Trevor

Am I right in thinking that the main differance between the A and B suspension set ups is the amount of castor angle?

Carl
C Bintcliffe

My car does not load up at speed, it retains it's excellent and linear feel even at 100MPH plus (track and Autobahns only of course). It is quite tolerable at low speed as well even with the 14" steering wheel fitted. I do still run it on 80 section tyres (165s not the original 155s so a bit more rubber to handle)as when it left the factory and these give all the grip you need with the well balanced chassis. I haver seen the point of the castor wedges.
Stan Best

The car was originally designed with 7 degrees castor because the cross ply tyres that were common in 1962 did not run straight and true of their own accord - they tended to follow imperfections on the road surface. The high castor angle gives straight-line stability at speed.

Modern Radials try to run straight by themselves, so you can get away with less castor. This is a good thing because it must lighten the steering. Any amount of castor means that as you turn the steering away from the centre, not only are you overcoming the drag of the tyre on the road, but you are physically lifting the front of the car up. The more castor angle, the more you have to lift it. Now the front of an MGB is pretty heavy to lift with only the power of your arms, so if you can get away with reducing the castor angle, you have less work to do because you don't have to lift it so high.

There's a good explanation here http://www.240edge.com/performance/tuning-caster.html
Mike Howlett

Carl-
I think that you'll be pleased with the Brown & Gammons castor reduction kit. I installed a Quick Rack into my 1972 MGB and found the result was ponderous steering effort at low speeds. I put a Brown & Gammons castor reduction kit in afterwards and the steering effort became much more tolerable.
Steve S.

Don't mean to hi-jack the thread but is positive caster the same as being raked rearward (like the front forks on a bike). If so, it would seem that having more castor would also mean more negative camber when the wheel is turned. I currently work at an EVO shop, and the track guys are always playing with the front upper mounts to get the front struts to rake rearward more. I just don't know if thats called positive or negative castor.

-Bill
Bill Mertz

Has any motor vehicle had the top of the king-pin or equivalent in front of the rear in the last 100 years? I doubt it, which is why there is no concept of negative and positive castor like there is for camber. Cars are angled like a bike, to provide self-centering, whereas on a bike it is to provide a natural steering action as you lean the bike (watch any kid riding no-handed). Supermarket trolley front wheels at least have the opposite camber as the wheels are required to turn according to which way the trolley is turned by the operator, who have their feet on the ground. Some stores (B&Q in the UK) have trolleys where the front wheels are locked and the rears steer, and they are a right pain to use. I could never understand the camber on vintage and veteran cars - why would you deliberately make the track of the bottom of the tyre narrower than the top, when the wider apart the contact surfaces are the better, and when cornering you are going to be applying forces on the most heavily loaded tyre in that direction anyway? When you see a slow-mo replay of an F1 you can see how widely splayed the tyres are in a straight line, but under cornering the outside wheel and tyre becomes vertical so it has the greatest contact surface area with the tarmac. Why would anyone design anything different?
Paul Hunt 2

So these kits are affectively reducing the castor to reduce steering effort. But as I mentioned above, my understanding was that more casotr can improve handling because it increases the outside wheels camber during a turn giving more contact patch during aggressive driving.
Is my logic wrong here?
Bill Mertz

This thread was discussed between 15/04/2008 and 25/04/2008

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