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Lotus Europa Forums => Garage => Topic started by: jbcollier on Tuesday,June 25, 2019, 11:28:28 AM

Title: Brief thoughts on high speed handling
Post by: jbcollier on Tuesday,June 25, 2019, 11:28:28 AM
I’m in a 2000 kilometre road trip and have been experimenting with different techniques as drive through various twisty sections.

Yes, a Europa has a slightly nervous rear end if you are close to the limit and applying a light throttle.  This gets dramatically worse if you lift off.  You can really feel the rear lighten up and prepare to “exit the stage pursed by a bear.”  Reapplying the throttle, settles the car again, assuming you didn’t wait too long.  (This makes for an interesting time when driving hard downhill in the wet.)

However, if you come into the corner a wee bit slower and apply significant throttle, the whole car is absolutely planted and neutral.  Very, very confidence inspiring.

(S1, 175/70-13s all round, YMMV)
Title: Re: Brief thoughts on high speed handling
Post by: RoddyMac on Tuesday,June 25, 2019, 11:39:19 AM
John,
Where about's are you on your trip?  You're headed out to the Squamish, right?

As for the handling, I finally had mine up to 70 mph this past weekend, and all I can say is the my car isn't quite dialed in yet.  I don't know if it's alignment, front end lift, or slop in the steering rack (picked up a spare that will hopefully be better than what I currently have).

Rod
Title: Re: Brief thoughts on high speed handling
Post by: dakazman on Tuesday,June 25, 2019, 03:49:17 PM
 You guys are my inspiration. Your killing me.😀😀😀👍👍👍
Dakazman
Title: Re: Brief thoughts on high speed handling
Post by: 1970EuropaGuy on Tuesday,June 25, 2019, 07:42:53 PM
John,
Where about's are you on your trip?  You're headed out to the Squamish, right?

As for the handling, I finally had mine up to 70 mph this past weekend, and all I can say is the my car isn't quite dialed in yet.  I don't know if it's alignment, front end lift, or slop in the steering rack (picked up a spare that will hopefully be better than what I currently have).

Rod
I notice a light front between 70 and 80 MPH with my S2. I'm planning on adding a small spoiler similar to what's on the Twin Cam. Have you lowered your car to European specs? Made a difference on mine.
Title: Re: Brief thoughts on high speed handling
Post by: BDA on Tuesday,June 25, 2019, 08:00:52 PM
John, when you get a chance, I'd like more information about your setup: alignment specs, ride heights, spring rates, tire pressures, etc. In fact, In fact I think it would be handy to have a collection of setups along with comments. Then others who are struggling with dialing in their car could see what has worked (or not worked) for others.

I am planning to start to seriously work on this in the near future and I'll be posting my results.
Title: Re: Brief thoughts on high speed handling
Post by: Bainford on Wednesday,June 26, 2019, 08:37:18 AM
It is phenomenal how well these cars stick when cornering under throttle. The more throttle through the corner, the better they stick. I enter at a seemingly slow speed, then apply as much throttle as I can, accelerating as hard as I dare throughout the entire corner. The trick is judging how much throttle to use, as running out of acceleration before you run out of corner gets tricky. Got to watch those deceivingly long sweepers ;)
Title: Re: Brief thoughts on high speed handling
Post by: RoddyMac on Wednesday,June 26, 2019, 09:24:02 AM
Quote
Have you lowered your car to European specs?

Mine's not exactly built to standard specifications, but it is an early type 54 so would have been built to European specifications. 

I am tempted to try either a spoiler or canards, and/or a ducted front lid.  I had a spare front lid that's quite damaged (two pieces), which would be a prime candidate for making the the ducted lid.  But, I would have to switch to a different radiator that would work with the duct. 
Title: Re: Brief thoughts on high speed handling
Post by: jbcollier on Wednesday,June 26, 2019, 05:20:09 PM
Mine is an S1 with stock springs (rate and length) on AVO shocks supplied by Banks.  The shocks are adjusted to the mid-point + 2 clicks.  The trunnions were replaced with spherical joints as supplied by Canely.  This results on height reduction of an inch or so and the front springs are now compressed a wee bit too much to maintain the set ride height.  A wee bit longer spring would supply the cure though it all functions just fine as is.

There is a twin link at the rear (Banks), and adjustable lower links (RD).  The lower links are set to match the stock lower link length and the camber is set via the upper link.

Settings are all factory with a bias to negative camber.  Toe is 3/32” at the front and 1/8” at the rear.  Both are total settings across both wheels.  A professional wheel alignment is a must so you can check your included angle (or kpi).  Uprights are easily tweaked and one of my originals was.

Ride heights are set with reference to the diagram in online manual (and on my photo site).  Measurements are off the bumpers.  The front is set a 1/2” inch low.  The rear a 1/2” high.  Both deliberately.
Title: Re: Brief thoughts on high speed handling
Post by: jbcollier on Wednesday,June 26, 2019, 05:28:50 PM
As I accumulate more miles on the Europa, I find it more and more like my motorcycles.  If I approach a high speed corner worried and tense, my tentative and timid inputs unsettle the car, and by extension myself: an unhappy negative feedback loop indeed.  However, if I drive into the corner, engine thrust settles the car firmly onto the road.

Forgot to mention my tire pressures.  28 at the rear and 18 at the front.
Title: Re: Brief thoughts on high speed handling
Post by: jbcollier on Wednesday,June 26, 2019, 05:35:44 PM
Rod,  I was headed to Squamish but my plans changed suddenly due to familial obligations.  I just ended up going to the Kootenays via Jasper and the Icefield Parkway.  Honestly can’t complain much.  The roads were fantastic and somewhat sparsely populated what with the younger set still interned.

I will be headed to Squamish proper, and Port Alberni on the Island in a week or so.  Again, though, family “obs” will have me transiting the lower mainland at an inauspicious time of day (early afternoon on July 9th).  I promise to head back for one of the B.C. Lotus meetings before year’s end.
Title: Re: Brief thoughts on high speed handling
Post by: BobW on Friday,June 28, 2019, 01:52:55 PM
I've been running 20 front and 24ish rear on the highway but my rear tires are wider than the fronts. I've noticed that the car seems to feel better with the pressures balanced left to right, though why that should be when I and the gas tank are on the same side is curious.

The Brits on the Beach show in Ladysmith is on July 14, if you'll still be in the area.   
Title: Re: Brief thoughts on high speed handling
Post by: surfguitar58 on Saturday,June 29, 2019, 07:30:48 AM
Here is a question for all you handling gurus: there is a lot of discussion on this forum about dialing in the optimum camber, toe, caster, whatever, can I assume this is a moot point for a stock TSC with fixed link lengths, and that the folks doing the discussing have upgraded to adjustable suspension links?

The car seems beautifully set up with the fixed geometry suspension and stock 175/70-r13s up front and 185/70-r13s in the rear. Am I going to screw up Colin’s beautifully designed suspension geometry if I switch to slightly smaller diameter, wider, sticky Toyo 205/60-r13s rear and 185/60-r13s up front?

I have not had the opportunity to push my Europa to its handling limits. Not that I haven’t tried, is just that the limits are way beyond my expectations and I haven’t found a safe place to push it harder.
Title: Re: Brief thoughts on high speed handling
Post by: jbcollier on Saturday,June 29, 2019, 08:05:10 AM
I'm mostly stock up front (different shocks and spherical joints instead of trunnions) and I only fit the twin link to eliminate suspension loads on the punny u-joints.  All my settings are within stock parameters.

I assume you have TC/S.  As long as you maintain the front/rear tire size difference, you should be fine.  My only question would be why are you fitting larger tires if you are not running out of traction?  Larger tires are, generally speaking, heavier and more prone to tram-lining.

It may sound strange but I like stock-sized tires.  I can have some fun at low (relatively) speeds.  Why do I want a tire that won't slide until I pass 1.xGs?  Where can I do that on the street and not get locked up and then rogered with a splintery broom handle?
Title: Re: Brief thoughts on high speed handling
Post by: EuropaTC on Saturday,June 29, 2019, 08:38:52 AM
Here is a question for all you handling gurus: there is a lot of discussion on this forum about dialing in the optimum camber, toe, caster, whatever, can I assume this is a moot point for a stock TSC with fixed link lengths, and that the folks doing the discussing have upgraded to adjustable suspension links?

The car seems beautifully set up with the fixed geometry suspension and stock 175/70-r13s up front and 185/70-r13s in the rear. Am I going to screw up Colin’s beautifully designed suspension geometry if I switch to slightly smaller diameter, wider, sticky Toyo 205/60-r13s rear and 185/60-r13s up front?

I have not had the opportunity to push my Europa to its handling limits. Not that I haven’t tried, is just that the limits are way beyond my expectations and I haven’t found a safe place to push it harder.

If you have standard components then the only things you need worry about are the toe-in which you'll have seen we discuss quite a bit. It's important to have rear toe-in on the Europa and compared with normal cars it looks a lot on the TC & TCS.

But everything else is fixed on a standard car and there's nothing wrong with that. You won't mess up the geometry with larger tyres unless you go wild, there might be a bit of speedo error due to turns/mile on smaller diameters.  I can see the attraction of modern rubber (done it myself) but if you're happy with the standard set up, are retaining the Lotus alloys and can get decent quality tyres locally I think I'd stick with OEM sizes.   I went to 6" wheels for 205 width.

B rian
Title: Re: Brief thoughts on high speed handling
Post by: GavinT on Saturday,June 29, 2019, 06:08:59 PM
The car seems beautifully set up with the fixed geometry suspension and stock 175/70-r13s up front and 185/70-r13s in the rear. Am I going to screw up Colin’s beautifully designed suspension geometry if I switch to slightly smaller diameter, wider, sticky Toyo 205/60-r13s rear and 185/60-r13s up front?
Way back in the late 70’s when I first got my S2, it was on the stock steel wheels/tyres. I acquired some genuine 5” width Minilites to install after the rebuild. They came from an Elan and 5” was apparently about the maximum on the rear without bashing spring perches etc.
The Minilites came with Avon 165/60 tyres and those tyres absolutely transformed the car.

I’ll leave out the fact that, over time, the tyres somehow developed an ‘out-of-roundness’ which translated to an increasing vibration which I couldn’t find for ages.
I chased that vibration through suspension joints, U-joints and practically everything till the local tyre guru picked it up while doing the wheel balance yet again.

Anyway, all else being equal, lower profile tyres will cause the car to react faster than a higher profile tyre.
It’s the same with stiffer springs.

Sometimes it’s easier to visualise these phenomena in terms of weight transfer.
While the weight of the car hasn’t changed, lower profile tyres or stiffer springs will permit a faster change of state - e.g. going into a corner.
That’s a good thing on the track but you might not like it if you happen upon a patch of damp leaves on a shady corner of a twisty mountain road.
Caveat: I’m certainly no expert.
Title: Re: Brief thoughts on high speed handling
Post by: literarymadness on Sunday,June 30, 2019, 06:30:01 PM
Original Steel Wheels on the S1 and and S2 are 4 1/2 inches wide, while the Lotus Brand Alloys are 5 1/2 inches.The acceptable width range for a 185/60R13 is a rim 5-6.5 inches wide and a 205/60R13 is a rim 5.5-7 1/ inches wide.  Those Lotus Brand rims do well with those sizes. The smaller 60 series reduces the ride height by 3/4 of an inch which should slightly increase handling.  I also have experimented with tire pressures and 16 psi on the front 26 psi on the back seems to offer the best handling characteristics. Those 205's seem to like -1 to Zero degrees camber.
Title: Re: Brief thoughts on high speed handling
Post by: Bainford on Tuesday,July 02, 2019, 08:30:07 AM

The car seems beautifully set up with the fixed geometry suspension and stock 175/70-r13s up front and 185/70-r13s in the rear. Am I going to screw up Colin’s beautifully designed suspension geometry if I switch to slightly smaller diameter, wider, sticky Toyo 205/60-r13s rear and 185/60-r13s up front?

This paragraph reminded me of once reading that Colin was in favour of non-adjustable suspension on road cars, suggesting that if you make it adjustable, 'they' will only screw it up. He proceeded to make reference to Weber carbs, and how much damage 'they' can do in five minutes armed with only a screwdriver.