Getting the best out of standard suspension components for touring driving today

Ok so this is hopefully a topic for Clive (@CliveR ) to lead and weigh in on since this is what he did professionally….hopefully we might all learn something …. Non engineers amongst us would be greatful for you wisdom

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There’s been a terrible misunderstanding, I’ve never been accused of wisdom before. As a calibration point my father was given to calling me the smartest idiot he knew. I never worked out if that was a compliment or an insult, maybe that was the point.

I’m happy to join any discussion although I’m probably less qualified than many members. My single drive of an E-type was in 1972, my ideas since then are formed from pictures and simulation. I’ll drag some thoughts together to get us going.

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I think I can take a whack at this: for the vast majority of street driving, the best way to get the best out of standard suspension on the E type, is to make sure that all the bushings are in top condition, the tires are properly inflated, and by and large, you can’t do any better than that.

Please let us limit this discussion to ‘standard street driving.’

Even with Tweety’s mostly OE suspension bushings, bog-standard ARBs, and with nothing more than a slight forward rake, on street, I never felt the lack of capability.

Even on-track conditions, I found by appropriate tire pressures, I could mostly overcome any of the inherent understeer of the chassis.

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I’d like to build on what Paul says to point something out. Once I had driven my street car on a proper track, with no need to worry about speed limits, on coming traffic, rough pavement, and hard immoveable objects just off the paved area, I realized that driving my car anywhere close to it’s cornering performance limits on public roads was going to eventually end badly. As such, I tend to drive pretty passively on the street. I think the standard suspension, set up in good condition with good tires, is plenty adequate for 8/10ths steet driving. I would also mention that stock brakes, in good condition, are very important.

Also, it is very humbling to spend some time with an instructor on a track, where you feel like you are doing better and better each session, only to hand your car over to the instructor and have him/her immediately turn a substantially improved lap time, wiht the exact same equipment. Most of the improvments to get “the best” out of our driving, can be obtained by improving the nut between the seat and the steering wheel.

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I don’t question that statement, nor anything Paul says above. You gentlemen are the subject matter experts, by definition.
I’ll ask another question - is there merit in extending the capabilities of the car, even if we don’t see the need for that in the sane street driving of this discussion? “Because we can?”
I hope the answer is at least a qualified yes, or I’m out of a job.

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Paul, can you elaborate on that?
It is well known that the E-Type steering becomes light at speed because of a tendency to lift the nose.
Does a small rake improve that?

You covered two of the items on my starter list. I would add to that:

steering. Naturally you want to be sure the column is well aligned and free of friction. I’ve read some interesting tales of underhood heat affecting steering friction, that should be understood and fixed. Likewise the rack, of course. Peter’s experience with his OTS car, and reading the forums, convinced us to go for a new, purpose made rack from a premium supplier. This might be a useful route for others as it’s a reversible change when it’s time for originality. A secondary gain of a custom rack is that you can specify the gearing and adjust the ball-joint spacing to optimise the bump/roll steer. I’ve seen a discussion about ball joint materials, I’d want to be sure I had a low friction pairing to minimise steering “stiction” and get best steering feel.

damping. A huge subject, at least as powerful as the tyres in overall effect. I wonder if there’s an available damper that really optimises the tuning to the tyres, springs, structure, bushes etc. I’m sure the original parts were skilfully adjusted at the time but damper technology has come a long way in 60 years. Have any of the after-market parts received the deep level of tuning that’s required to get the dampers pulling all the aspects of the car together and making it sing? Maybe there’s room to get together with one of the suppliers and work out a spec to get the best from an original car with a damper in the original location. (We only went for mono-tubes to get access to a tuning kit, a fortunate decision as we later decided to lean the front dampers at an angle that would not be feasible with twin-tubes). There’s an assumption here that the standard structure would accept revised, presumably higher, damper loads - should not be a high risk considering it already sees peak bump loads from the jounce bumpers.

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Well, I don’t want to be a party pooper so of course the answer is Yes.
Many of us don’t have access to a proper track but I bet that all of us have “a favorite road” which challenges our car and our personal abilities. If for no other reason than to extend the margins of safety when challenging “our road” it would be good to have the best suspension setup possible.

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I am given to understand that Norman Dewis covered over a million miles fine tuning the E-Type handling and ride so the heavy lifting has already been done. 185 VR15 tyres make a huge difference to the way the car behaves on any surface and the stock dampers (Boge were clones of the Girling NFP/NAP spec shocks) beat anything else you might consider fitting; don’t even go there with Koni’s they are very ill suited to the E-Type. The biggest change you can make to the handling is by adjusting the tyre pressures to match your driving style. I found 32/32 was not for me so I now run 30F/35R with Michelin XVS 185VR15 tyres on 5" wheels. To get to those figures took me an entire day covering the same circuit of mixed road over and over with 1psi changes to pressure.

As for experimenting with modern spec shocks you need to be aware the E-Type is not the stiffest of chassis as Pressed Steel R&D department reported in late 1963. The rear twist was quite good but the front twist was not so stiffer shocks at the front will compromise the frame body junction. Details are recorded in Porters 'Definitive History.

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Good question.

As the years roll by I’ve found myself being much more selective about modifying/updating things. Too often the effort and expense didn’t yield a worthwhile, real-world benefit. The juice wasn’t worth the squeeze, as the saying goes.

However…

Almost every car I’ve owned has rec’d minor suspension upgrades. Larger and/or additional anti-roll bars, performance-oriented shocks, wider wheels, tweaking alignment settings. Things of that nature.

I’ve never regretted these modifications. There has always been tangible improvement and increased driving satisfaction even at modest/sane/normal speeds and conditions.

FTR, I’ve never lowered the suspension, used stiffer springs, or relocated suspension components.

I’ll disclose that my XKE-specific experience is near zero so take that into consideration. But in my ignorance I don’t see why an XKE wouldn’t benefit from minor suspension mods.

Cheers
DD

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as said above, tires, dampers, bushings, steering, brakes (and the whole package) in good repair. Easy to say, time consuming, but can NOT bandaid the basics.

With that I find the E-type to be an outstanding performer for street driving. It is not the same as a modern BMW M or Corvette. But I find its refined but relaxed character to be very enjoyable to drive at speeds that will keep us safe and out of jail.

But being a retired ride and handling development engineer, I can’t help a few little tweeks.
I use urethane jounce bumpers in the rear. Very soft entry and good damping. Also adjustable dampers (GAZ), starting at the low end and dialing up until the wheel motions have minimal reverberations.

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not only tire pressures, but the actual tire itself can make a lot of difference. Explore the Tire Rack videos where they test drive different tires on the same vehicle (not E Types of course) but it will give you an idea of how much difference, what the differences "feel " like. Since we can’t just switch a whole bunch of tires to test, we will have to go on the experiences of others with various tires, and then we still do not know if the bushings and rest of suspension was in good condition. Proper ride height matters as it affects how the suspension and steering work. Then add…how much weight do you have in the car–with or without passenger, and what is carried, and full fuel or not. Makes more difference than you may think, as it affects weight distribution.
Nick

Many of you have mentioned that the bushing need to be in good condition and that stock bushing maybe the best. I’m about to replace all the bushing on my S2 front suspension and would appreciate any insight into what is the consensus on which ones to buy and who from. I note that SNG has three types, being stock rubber, black poly and red poly.

Many thanks Andy 1969 S2 FHC

I call that, “conditioning the spacer.”

:stuck_out_tongue_winking_eye:

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A small rake, and a 1" chin spoiler does wonders!

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Sure!

There’s nothing wrong with doing that at all… I’ve done it to many streeter, at the request of the owner.

But to limit the question to, “what can one do to an E type to substantially improve its basic handling package, while it’s being driven on the street,” I still maintain that the car itself, as delivered and as Harvey pointed out, is entirely adequate for up to 8/10ths driving, and that is a level that, frankly, very few street drivers can attain.

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I’m reminded of the endless debate and discussion regarding the rear anti-roll bar on the XJSs. Early cars had it, then it was dropped, then reappeared on some cars for a few years, then dropped again.

There’s a video of Norman Dewis being interviewed and this very subject came up. Dewis tested the early XJSs on the track and advised his superiors that “The car doesn’t need a rear anti-roll bar” and they should save their money.

As it worked out they did install the rear bars during the first 4-5 years of production.

Anyhow, some have interpreted “Doesn’t need a rear anti-roll bar” as “Don’t install a rear anti-roll bar” or “You won’t like having a rear anti-roll bar”. Of course, Dewis never said those things and I’ve yet to hear from anyone who added one who wasn’t delighted with the results… while at the same time agreeing with Dewis that the car doesn’t need one !

Without going way into the weeds on this I reckon there are mods you can make that will feel great a 6/10ths or 7/10ths but which might become an actual detriment at 8/10ths or 9/10ths…for those drivers who actually drive to that level.

Cheers
DD

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To that end, I again offer up this short but sweet, and entirely accurate little article

https://forums.jag-lovers.com/t/datsun-handling-article/406325?u=wiggles

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With my education about jouncers now complete ( well at least I know what they are now) ….it’s great to see some great thoughts from those who have much more experience and knowledge from me……I am constantly amazed by the number of professional ( retired or not) that have done the stuff we chat about for a living and what an eclectic lot we really are …it really adds to the enjoyment of these threads and of course those that have vast experience working on these cars .

I do have question about jounces …… do these eliminate the need for the bump stops at the rear and does that mean that a 205 tyre will get more rubber on the road …but then again the steering becomes heavier …… so compromise again…. Adhesion vs drivability for street driving ?

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I think there is some misconception about wider tires. The footprint of a tire “on the road” is purely a function of force divided by area. So for any set car weight, the area of the tire contacting the road will generally be the same regardless of tire width. Now up to a point, you can get more contact patch by reducing the air pressure in the tire. But most folks I know, when they are going on track, add pressure! Seems counterintuitive to me.