Roadholding comparison

Yesterday I did half an hour in one of my XKs. A 150 FHC with Michelin Pilote X tyres, upgraded front anti roll bar and the rest pretty much a standard 3.4 car, with a very sweet Moss box.
I then did the same drive in my father´s old S-type. It now has a 4.2 with twin HD8 carbs, upgraded anti roll bar and like the 150, all new suspension parts, metal and rubber. New very good Michelin radials.
They behave incredibly different… The XK is like a gokart, whereas the S-type rolls when turning the steering wheel back and forth at 50mph, and it nose dives noticeably on firm braking.
The XK does neither. I have another 150 with the same tyres and it behaves just like it except it has a stronger 3.8 L engine. I have other XKs with other tyres, both radial and cross plies and these are slightly less gokart like.
And then I love my 420G which are more gokart like than the S-type. Can´t really explain why, but they dont roll as much either forward or sideways. Wheels further apart? Stiffer springs? Lower seating position???j
And my E-types hold the road very well, but the XKs are in the same league on twisty country roads. I have the 3.54 with OD, rather than Jaguar´s 4.09. This way I can go between 3rd and 4th on country roads, rather than between 4th and OD. I like the OD to be for motorways/>70mph only.
Just a few reflections from Sweden

The 420G has stiffer springs , that’s what Coombs used on there MK2’s , just cut down !
I added a set of GAZ dampers to my MK2 , helps the body stop rolling no end !

Interesting observations. My '72 XJ6 SWB and '62 E have largely refurbished suspensions. The XJ6 does need new suspension rubbers at the front. Both handle well but the XJ6 feels a little flatter and more confident - it rather entices you to go harder. A long time ago I had a local Holden with independent rear - not a bad car from a handling perspective - but the old '72 would eat it alive. My Mk2 is standard and wouldn’t stay with either of the others.

My S1-II XJs handled much sharper than my 420G, especially with poly-steering bushes

They have a “anti-dive” front suspension design under braking, light years ahead of
locally built sedans designed 20 yrs later

I have put largely poly bushes in my 420G, it feels a bit “floaty” when driven really hard.
Interestingly, MKX-420G have a steering system almost identical to 90’s Landrovers

The next step to finalise my 420G front end is rebuild steering box & brakes + new tyres

This is getting good…

Tony: the XJ has rack n pinion, which is always going to be tighter, as we all know. My Marles Varamatic boxes are rebuilt but this is mainly a dry vs leaking box operation. One box unfortunately has a worn worm, and cannot/should not be further tightened.

I don´t have poly bushes in the saloons, right or wrong. Don´t want to lose the Jaguar feeling. The XJ suspension, with shock absorbet at an angle and separated from the spring is brilliant.

I have stiffer front springs on one G. But they were also longer, so I have cut them bit by bit. The distance from floor to wheelarch, just by the centre of the wheel is now 64 cm.

I use the XWX 205 VR14 which are superb. 1,8kg in urban conditions and 2,3kg on the motorway. The oldest set are now 10 yrs with little wear and very fresh rubber.

Skickat från min iPad

My MK2 has all poly bushings, stock springs and shocks, thicker roll bar front and back, lowered 1" in the front, 15x6 wires with firestone radials, and a steering rack conversion. Handles wonderfully for an old car and for a sedan. Still leans a bit on hard turns and I need to lower the rear end an inch or two (the leafs are too tall) but I’m constantly surprised by how well it sticks to the road.

if you have body roll, and your springs and shocks are good,you could try poly bushes in the swaybar, probably wont make a huge difference