Amazon: Critique my Suspension set-up

[TomTom]

Hello Forum,

Hope everyone is still managing to exercise their cars in these weird times.

I know this is a common topic but I would like to ask for a critique of the current suspension set-up on my 1970 Amazon 2-door and suggestions for improvement.

The aim is for rock-solid motorway and fast-road use but, crucially, as smooth as possible over the many road humps and potholes in my area.

Current set- up is as follows:
Thicker IPD front anti-roll bar
Original springs, a bit tired
New oil shocks/dampers
Poly bushings on top front wishbones
Original Volvo rubber everywhere else, some coming to the end of their life

I know there is some hate for the thicker front ARB. All I know is that I can drive at 95 (on the autobahn naturally!) and the car is rock-solid, no fishtailing at the rear and no lift at the front. But could I achieve the same solidity with lowered progressive springs, new gas shocks and the regular front ARB?

New set-up I’m considering:
Keep thicker ARB (??)
Amazon Cars fast road springs (-25mm progressive)
New gas shocks (do Bilstein rears still need re-valving?)
Blue superflex bushes everywhere (this based on the poor life-expectancy of new rubber) except for poly on top front wishbone and axle end of panhard rod
Tires are newish Vredestein.

Has the Quatrac-5 replaced the Sprint+

I’ll be really grateful to get your views. With the current restrictions on flying and 14-day self-isolation on returning to the UK, I think there will be quite a few UK-based driving holidays this year.

[Derek UK]

Your new spec looks OK. Keep the IPD front bar. I've not read bad comments about it. Using it with their rear bar isn't for everyone and that often gets taken off again. Can make the back end a bit skippy and over steery. Bilstein's are good but need to be ones for normal road use and not sport. Tyre choice is OK. Wheels not mentioned but having 5 1/2" is a plus.
High speed cruising needs good brakes so keep an eye on them.

[TomTom]

Thanks Derek. Wheels are standard on 165/80/R15s.

I’d be interested in alternatives to Bilstein for the rear to make it less skippy.

Tom

[Burdekin]

Have heard these are good but not cheap https://www.classicswede.co.uk/Prote...5_4631878.aspx

[Derek UK]

Originally Posted by TomTom

Thanks Derek. Wheels are standard on 165/80/R15s.

I’d be interested in alternatives to Bilstein for the rear to make it less skippy.

Tom

Don't be tempted by the white bodied KYB shocks, they are really stiff and uncomfortable. Took a set of these off a '66 4 door and fitted a set of basic Monroes and all was well. Perhaps not the best and they can go off a bit after 20k miles or so but are cheap. Certainly a lot better than many shocks on Amazons that have done unknown high miles. They are items that seem to work but are tired out.

[Bracpan]

Originally Posted by Khe Sanh

Have heard these are good but not cheap https://www.classicswede.co.uk/Prote...5_4631878.aspx

I fitted all that kit (only had GAZ shocks then) and all i had to do was play around with what settings i preferred on the shocks and it was job done...remember anti r/b is doing very little when travelling along a strait smooth road they only come into play on a corner, the progressive springs help with that so i left my ARB standard..

[blueosprey90]

I can't really make a positive comment on a car that is as modern as a 1970 model, but I really like the Vredestein Sprint Radials.

I've run the 165HR15s on my '59 MGA race car for about 10 years, although that is perhaps a lighter car. They are a good, grippy summer performance tire. They aren't supposed to be used below freezing. They provide good stopping and good cornering at higher speeds and are quite predictable in that they scream pretty loudly before letting go.

I think the Quatrac-5 is intended to be the all season version of the tire. I believe the tread pattern is similar, although I'm not sure that you can get the Quatrac-5 in a 165-15 size. But my guess is that you can probably use up to a 185-15 without too much trouble.

[classicswede]

I'm no fan of just the thicker front ARB.
With no ARB at all the car will be rock steady doing 100+ on the motorway. Where the problem comes is with sudden change of direction, with just the front bar the front is dampened but the rear is not. This will often result in the rear fishtailing.

You do not need a thick rear bar, I do some thin rear bars that will bring the balance back.

If road comfort is the goal then 25mm lowering is not bad, full height rally springs a bit better and +25mm gravel springs are even again. I presume you want comfort with still running the 165's rather than a modern wider tyre that will give you much better grip.

Shocks, of what I offer the protechs are a bit better comfort wise. The yellow Bilsteins are a long way off what you want. A Derek suggested even some cheap gas pressure shocks would not be bad (not KYB)

Bushes, top wishbone bushes are a must for poly. The rest can all be rubber or I could make a set of soft poly as a happy medium. I am happy with full poly myself but I do like everything firm

[Quarterless]

I pretty much have your suggested set up on my estate with Gaz lowered springs and shocks all round. I have found it great and love the way the car rides now.

[TomTom]

Classicswede: I will contact you for the soft poly bushes, thanks. My only experience of the normal front anti roll bar and no rear anti roll bar was my previous car which was decidedly light at the front at high speeds to the point where I didn’t really feel safe. My present car is exactly the same set up as that except with the thicker anti roll bar and as I said that suffers from no lift or wobble. This is completely unscientific it’s just my two bits of experience.

I like the idea of the adjustable gas shocks but will have to think if the expense justifies this flexibility. Knowing me, I’ll set them at a particular point and then never change this, ever.

Do the +25mm gravel give any more lurch when cornering, since the car sits higher?

Thanks.

Tom