This may be a dumb question... but is the S Tyoe fitted with a rear anti roll bar?
I can see brackets at the wheel end of the radius arms that look like they're designed to take drop links... but there aren't any.

 

As far as I know, they were never fitted with a roll bar. The arms are the same as the E Type, which does have a rear bar. I believe the track is wider on an S Type, so an E Type bar won't fit.

 

I do not think it is worth exploring that but instead upgrade your rear coil overs and front suspension components, and if you are not a purist, putting slightly wider rims/tires with modern performance tires will make a huge difference...

 

Fitting an anti-roll bar without making other mods, such as a stiffer front bar, reducing camber on the rear wheels or using the wider rear wheels mentioned by Primaz, is likely to increase any tendency to oversteer, which might not be desirable.

 

The S Type is a marginal oversteerer at the absolute limit. A bit tyre dependent. The rear anti-roll bars were never fitted to save money. All mounting points for the rear sway bar are there. They are expensive. The bar is available as a full kit. The width is between the MkX & E Type. I show an E Type below.

Harvey Bailey Engineering makes the kit. Excellent reputation.

 

Wouldn't making the rear springs stiffer make the ride harsher? A roll bar will keep the ride quality but help handling.

My car has the original springs with Koni Classic dampers and I think it's a bit stiff, the ride is bouncy. I certainly wouldn't want it any stiffer.

 

Never had a body roll problem with my 1968 S Type but then again I do not throw it into corners and roundabouts at 70 mph thinking I am Mike Hawthorn. Driving at the speed limit and the car hardly moves and the handling is taut no need to exceed the speed limit or have the car on its edge around a corner. My car is more about turning heads because people admire it rather than people shouting "********" at me as I screech around corners.

 

+1^

S Type roll looks far worse from outside the car than it feels inside the car but they roll quite badly.

The Harvey Bailey Engineering kit is the answer & works extremely well with no ill effects on ride quality.

S types have a slight float now & again on curly back roads with properly set spring rates & that's fine with me.

I'm happy with mine standard. I think the rear sway was about GBP 800 when I looked into it. If yours is bouncy the damping rates are out. Whether it's compression or rebound only trial & error will tell. My instinct says compression.







About max.

 

Both the images show the car being pushed further than you would push it on a normal road drive so standard is fine for me. My Dad used to rally and race his Mk2 and I agree when they were pushed the body roll was a lot but that would be all cars from this era and we don't drive them like this on the road.

 

For me I have upgraded the suspension with coil overs front and back, custom front A-arms, set it up with slightly negative camber, lowered the car but kept it not too stiff as I still want the car to be a comfortable cruiser & passenger car. By lowering the car that excessive body sway on those pictures never happens and the car is very comfortable. The sway bar might be ok with a bone stock suspension? but I think upgrading the suspension where you can adjust not just stiffness but compression & rebound, etc. and lowering it is better. When driving alone, many of you know I push my car way faster and harder than most. I have no noticeable body roll and the car handles pretty well without giving up comfort. To me these cars stock sit too high and if you lower the stance get more adjustable suspension with better quality springs, etc. you can keep it more of a softer ride and gain the handling without body roll.

 

I have them set on the softest setting, but of course they are not adjustable on the car. The rears are not the easiest thing to access to adjust the dampers, as the springs need to come off. Personally, I really dislike working with springs and spring compressors.

 

Yes working with springs can be a pain. When you are feeling relaxed wind on a little more compression damping. To this day it amazes me that Jaguar designed such a sophisticated suspension so long ago. It can still do a better job than over half the new cars on the road today. I'm running standard & I'm happy. We made the springs in SA for SA built cars so we can still get the spring rates perfect. I'm using fixed rate shocks.

 

Forum fart.

 

If I remember correctly, the Koni Classics (Special D?) allow adjustment only (or predominantly) to rebound. In spite of that, they do seem to work well (on Mk2s and Alfa's). A method of setting them is to start at the softest, drive over your favourite speed bump, increase the stiffness one click and repeat. Stop when the 'jitteriness' disappears. This process is bad enough on a MK2. It must be painfully slow to soul destroying on a classic S type. Spax may not last as long, but the adjustment screw is on the side and they (used to) cost less.

 

I am running QA1 double adjustable coil overs that have 18 levels of adjustment for both compression & rebound. With coil overs there are only a few diameters so that provides an enormous variety of springs to choose from and you can just adjust the collars to change the height easily; A good performance shop or performance spring/shock company can get you fairly close to the right spring if you tell them enough about your driving needs.

I find for the street to use moderately (you can be surprised how much stiffer you can go & without affecting comfort as long as you allow everything to travel) stiffer springs, lower the ride height, and yes start with a soft setup and drive it to get a nice feel. Most good coil over products have a long or lifetime warranty. Taking the car on some familiar switch backs makes it easy to get the compression at a nice level for your taste and then refine it with going over some dips in the road to dial in the ride height as low as you can without bottoming out and with a nice rebound to reduce floating, and minor tweaks to compression/rebound to get it to your preferences. I got the car as low as I can go without having my front ram air to not scrape on dips going at speed and that enabled me to keep the compression just stiff enough for decent handling at double the stated speed signs, yet when I drive at the stated speed limit people comment on how smooth and comfortable the ride is. People often make the mistake of trying to set the car too stiff assuming that is the only way to handle well, as well as using too stiff of a sway bar on the car... For my car I do not think a sway bar will improve things much to bother with it

 

This makes a lot of sense out of staying stock with the S type as original with fixed shocks, or just bolting on the Harvey Bailey Engineering kit should you wish the rear sway bar. The rear suspension is superb even by today's standards.

We don't have an F1 team of engineers & their proprietary equipment to simulate, measure & record multidimensional/directional damping.

When I see some of the IRS mods out there I just smile. The only one the makes some sense is the brace that stops the bridgepiece from rocking backward & forward on it's V mounts. (as shown on CAR SOS ~ Even convinced Mr keep it Standard ~ Fuzz, after driving multiple E Types with & without)

Many mods are done for stance alone & I understand that. If you have the money just do it. It's not going to improve handling. Especially mods that drop the tail of the vehicle.

 

Thanks for all the comments and information.
I'm going to stay with the stock arrangement. I won't be throwing my S type around any corners when its back on the road.
I did purchase and will be fitting adjustable rear shocks (SPAX). I fitted these to my xjs and didn't have too much trouble setting up the ride properly.

 

Sensible move. What I have done & the car is a pleasure to drive.

One of the biggest problems with fitting everything adjustable aftermarket is actually setting it all up optimally. If the average person is honest they don't have a clue on optimising the rear suspension vs the factory that put huge effort into it.

 

I started out with non adjustable shock absorbers on my Lotus Seven. Changed to fully adjustable Spax. You could alter the length for ride height, tension on the spring, rebound rates, great bit of kit and very expensive. Set them up once and never touched them again. Seemed like a waste of money at the time but changed the handling characteristics no end.

 

Yes ~ changing just one thing like the shocks is easy & wise & it was a kit car. Changing multiple things is where the difficulty comes. You are also more capable than many.

We had this problem with the racing team. A rider would come in & say the rebound damping is hopeless. We would hustle them off ~ do nothing. (Obviously pull the fork tops for show ~ pre external setting on Showa), send them out again & they would come back & say that's perfect! We knew our good & bad set up riders.