Stability at speed

[mark030358]

Never in my ownershp of my Sprint have I ever felt really comfortable driving at speed. The car was running on the origional steel wheels and Dunlop SP10's and had been previously set up as best possible.

So bit the bullet and went the whole hog. Four new Minilite 5x13, four new XAS 155x13, complete TTR rear suspension (including all drive shafts, due to QED 420 cams.. another story).

So all fitted ond off to the alignement garage.....

Front toe in 2 mm overall (interesting that the rods ran out of adjustment, I think the arms are slightly too long. Read this on another thread somewhere)
Front camber 1/4 degree negative each side

Rear toe in 3.1 mm per side
Rear camber just under 1/4 negative each side

and WoW!!!

Car is super stable, never been like this before at +100mph (allegedly) the car is rock solid and stable, no twitches, side to side movement, just fantastic. I have never had it so good before.

Over the moon .... just great.

Oh and running 19 psi front, 24 psi rear.

cheers

[stugilmour]

Wow Mark, thanks for posting your success and numbers. Very encouraging and gives a great starting point. Thinking I need more rear toe-in (have adjustable wishbones from Spyder), so will check against your number.

Just trying to dial out the last bit of stability issues on my Plus 2. I am considering the XAS's as my current Sumitomo HTR 200's have seen their best and they are now NLA . The car does not like the present miss-match of cheap Coopers on the rear and worn HTR's on the front. I can't find an H rated replacement in the popular Plus 2 replacement size (175/70/R13) here, so may bite the bullet and try the correct size XAS's or Vredestein's from the 'States.

Great to hear the XAS works well on the Elan. I always remember them as a great tire on my Alfa sedan back in the day. Have you had a chance to check them out in the wet yet? Memory may be a bit faded, but I recall them being tricky in the wet when they got worn & very good when new, but the Berlina was a heavier car? My current set-up is very questionable in the wet, hence the question/concern.

Anyway, congrats and enjoy!

[ericbushby]

Thanks Mark
I want some of that. I have printed that out for future reference.
Eric in Burnley
1967 S3SE DHC ( Not running right)

[mark030358]

Forgot to mention Kelvedon adjustable rear A arms.

cheers

Mark

[elansprint71]

Forgot to mention Kelvedon adjustable rear A arms.

cheers

Mark

The key element!

I had a quite a conversation with the Guru from Kelvedon earlier this year about rear-end steering. He believes, iihic, that, as the rear suspension is compressed, the toe-in/out varies considerably, this can be either as "bump-steer" where both sides are affected equally, or whilst in a cornering body-roll situation, where one side is in compression and the other going the opposite way.
Pat reckons (and we were talking about racing, rather than road; although the same principles apply) that setting the ride height is the starting point and then dialing in an initial amount of toe-in would help to keep things pointing better. However, there are a host of other factors to take into account (spring-rates...etc).

Interestingly several folks who know their onions have told me that, given a bit more budget, the Elan would have had a proper twin-wishbone rear set-up, rather than the cheapo MacPherson strut which it is saddled with.

[mark030358]

Pete, the rear setting was as per your post. ie 1/8"

cheers

[archigator]

Stu,
I had XAS tires (tyres) on my '71 Fiat X1/9 back in the day, and you recall correctly, they were squirrily in the wet. I recall taking a highway curve at no more than 40mph in a light rain, and the car broke loose and did a complete 360! Granted, it was a mid-engine car and a little more prone to not giving feed-back until one reached the cornering 'limit', but I was REALLY shocked when that happened! I don't know if the asymetrical tread doesn't pump the volume of water that a non-asymetrical tread might, but they were not as good in the rain as other subsequent tires (tyres) on that car. Bottom line: Be careful in the wet.

Gary
'71 Sprint FHC
Miami, Florida

[TroonSprint]

Forgot to mention Kelvedon adjustable rear A arms.

Mark, is the Kelvedon price of ?170 for one side wisbone assembly or for a pair? If it's just for a single side, then Spyder are cheaper, but if it's a pair, then Kelvedon are cheaper. I have some experience of rear toe in on my V8 MGB with IRS, so may fit adjustables to my rebuild Elan.

Thanks,
Mike

[mark030358]

Thats probably per side, I can't remember the exact price been buying them over a period of time.

cheers

Mark