Lotus Europa Community
Lotus Europa Forums => Garage => Topic started by: kram350kram on Thursday,February 11, 2021, 09:12:08 AM
-
Just a question on camber setting for the front suspension, rears are 1º neg. 0º is specified in the repair manual but with adjustable a-arms, wondering what most are running. Thanks
-
The workshop manual recommends 0 to +30'. That seems to produce pretty good results.
-
It makes a difference with the size tires you are running. Zero degrees up front for the stock 175/70R13 is about right but I have 185/60R13's up front so my camber is set at -1 degrees (recommended to me by Steve Smith at Twin Cam Racing in Sarasota). A wider tire normally does better with a little more negative camber than stock. Toyo recommends -1 to -3 for the 205/60R13's in the rear and I have mine set at -2 degrees.
-
BDA:
The spec is 0° +/- 30'
You don't want to run positive camber. I set mine to -30'
-
Hmmm. I had checked the TC manual (see attached is a screen grab from the TC manual) I had assumed kram350kram had a TC but that is an assumption I often make in error). It seems odd that the S1/2 would be different from the TC. I wonder if that was a misprint? I wouldn't want positive camber either and I was somewhat surprised to be reminded what the spec was.
-
Interesting, and odd indeed.
-
I'm going with misprint or typo.
-
Interesting. I looked at the handbook to see if there were any differences and yep, they are.
The handbook says you can have plus or minus 30' !
Brian
-
Which handbook is that, Brian?
-
It depends on what you do with the car. If you are just driving it casually 0 is fine. If you track or autocross you could run more but running more without the need will wear the inner a little more. I run -.75 degrees in the front and a little more caster. I used a pyrometer to decide what is best for the tire for autocross. If I only drove on the street I would still run a little, maybe -.25-.5. Even with the low tire pressure, they don't seem to need much camber as a heavier front engine car would.
-
Which handbook is that, Brian?
Mine !! :)
Flippancy aside, it's also in the S1 reprint that John organised a while ago so I suspect it's something they've had from day 1 and carried through all of the model handbooks. It's a bit irrelevant on the standard car because altering it means deliberate tinkering so I bet it's just there to identify any kerb damage to wishbones or uprights ?
Brian
-
Ahhh... That handbook!
I think the TC manual misprinted the front camber spec. I agree, they put that in to tell if something is bent.
-
Yup, to check for chassis damage. The swivel-pin inclination tells you if the upright is bent, a very common issue.
-
I think there is also something to be said about tire manufacturers' recommended camber settings for a particular tire. I run my tires at -1 degree in the front which is the least negative recommended setting of the manufacturer and only a half degree more negative than the original factory recommendation. I run -2 at the rear.
SETUP & CARE
Toyo Tires recommends the following general setup guidelines for the Proxes R888R:
Operating Temperature: 160°F to 220°F
Hot Inflation Pressures: 32 to 38 (psi)
Camber: -1° to -3°
Caster: As much positive as possible
-
I think it'd be a brave man that would follow Toyo Tires recommendations over that of the vehicle manufacturer.
Though I suppose if you're going to run 38 PSI in the front tyres, you might be looking for some negative camber to regain a little steering.
-
I don't run 38 psi. That 38 psi number is meant for a much heavier car. I run 18 psi in the front and 24 psi in the back. My front camber of -1 is only a 1/2 degree or 30 minutes more aggressive the Factory the factory range (far from radical). Tire technology has come a long way in the last 50 years. The factory spec was based on a 155/70R13 or a 175/70R13 front tire. A softer rubber compound tends to work better with a more negative camber. If I was running OEM tire sizes then absolutely I would go with the Lotus factory recommendation.
-
I didn't actually think you'd be running 38 PSI, Literary.
The fuller context of their set-up advice sheet makes more sense.
How do you like the -1° on the front?
I haven't tried it due to the non-adjustable nature of the stock arms but always thought slotting the uppers was easy enough for a trial.
But I reckon you're right about modern rubber. Toyo even says their R888R has a stiff construction which is some distance from our standard Lotus spec.
Kinda makes one think we should make the Europa stiffer all around to take advantage of better tyres which are also invariably flatter as you go wider.
With apologies for the topic drift.
-
Speaking of slotting the A-arms, I saw where one guy slotted his and made plates that fit inside the arm that have holes in a position for different cambers. I don’t think I described that very well but hopefully it makes sense. If not, let me know and I’ll try again and maybe I can find the write-up and provide a link.
-
What did with men was slot them and use a large washer. Made the adjustments and then tack welded the washer in place.
-
Looks like there are retail kits available.
Don't know how readily adaptable they might be for our arms - two holes needed to alter the top ones.
https://cmwraceparts.com/proddisp.php?pn=JRP15050
-
@GavinT: Before I made the switch to Adjustable Uppers, the camber on the front wheels of my TCS were asymmetrical, Zero degree on one wheel and -30' on the other. So of course just being able to make the front symmetrical would have been an improvement alone, but set at -1 degrees, the front end now feels more stable especially at 80+ mph speeds.
-
From the Jensen manual......
"With the lowered suspension settings, it is necessary to decrease the negative camber of
the front wheels. This was achieved by moving the lower suspension arms outer pivot point
inwards. This was carried out by slotting the existing holes in the arms and installing drilled
plates to locate pivot in desired position (0.158 in. per l° of camber change). The plates fitting
securely in channel of lower suspension arms."
Gives a good idea how far you need to move things to change camber.