Club Triumph

Good pictures here Tom.  Your front outside wheel looks to have positive camber on it.  Have you modified the front suspension in any way and does the car understeer?  

I know how you would normally correct understeer but that can lead to the back end of the car rearranging the hydrangas at Goodwood    :-/

Thanks, Chris.

Yes, but too much negative, and there is a trace of understeer. Certainly negative when pushing on, but fine under normal driving situations.

More development work needed, and I feel the dampers could do with turning a few clicks to tighten the front end.

Always a compromise when used on road and track.


To be continued.


Cheers.

Positive camber is when the top of the wheel is further out from the center line than the bottom, negative is the other way round.  I have used negative camber to counteract understeer, but you only need a maximum of as much negative camber as the car rolls.

Small amounts of toe in and out can also affect steering, but I don't know what the effect is, can anyone else add to this.

Also the relative roll stiffness of the front and back ends affects under / oversteer.  I think the relationship works increase the stiffness at the back, understeer will increase; reduce the stiffness at the front understeer will reduce.  If I am incorrect in this please will someone point it out and provide the correction.

You can see from this that changing the roll may also need a change of camber angle and tyres can also alter the balance.  It needs someone that knows what they are doing to sort this out.  You have used Revington TR in the past haven't you. They should know how to set up a TR6, but there are others that you may know as well.

Have a good Christmas all.

Front end excess roll stiffness, front wheel lifts, car unsersteers

Body roll appx 1.5 degrees, front camber appx -1.5 degrees, neutral car

Hi Chris,

I recall, your TR7 handles beautifully, very neutral. I have been around Cadwell, and I think Silverstone. Great handling car.


Do you still use the Saab. ?


Cheers.

Hi Tom

I have not had it out during 2014, or any of my other Saabs for that matter.  I am still on restricted activities. I still need to sort the black Saabs excessive understeer and when that is done I intend to take it to Spa for a TD. Maybe in 2016.

MyTR7 is hors de combat with a coofered clutch master cylinder, which may not be easy to fix.  When I had the engine upgrade Revingtons provided an extreemly grippy but heavy clutch.  This works smoothly and well but needs immense pedal pressure that did for the (old) master cylinder only just before it did for my left leg.  This was when I took it to Cornwall in October and had to drive back without a clutch.  I doubt if my TR7 needs anything more than a TR8 clutch, but it would be expensive to take the clutch out and put a new one in, so I'll have to find an upgraded master / slave combination that gives just about double the thrust on the clutch fork and fits a 7.

Chris

If you have space under the bonnet, why not servo the clutch??

A better, easier solution for a clutch that is too stiff is a smaller clutch master cylinder.

The travel will be longer, but you'll need to press less hard.

Here's AP Racing's list of sizes - for brake MCs but they are exactly the same.
http://www.apracing.com/Info.aspx?InfoID=98&ProductID=998

But OE size was 0.75", until Triumph went to a 0.7 for a light pedal after 1970.  If yours is the larger then the later version might suit - do not go for a big change!

JOhn

Thanks John, That's great.

I have been thinking that the solution would be something like that and that I would replace both cylinders as both are old.  I'll have to get the old ones off and work out what dias they have and get some new with an improved force ratio.  I'll probably need to improve the ratio by 2.

Colin, I had wondered about a servo solution.  I have never heard of anyone doing it before.  I'll keep it up my sleeve as a plan B.

Cheers, All