Suspension setting

[vee12eman]

Hi,

I'm having one of my best Christmas days in a long time - under the E-type as my lovely wife is at work until tomorrow morning. (Christmas has been postponed here!)

Anyhow, I am changing the rear shock absorbers for Gaz adjustables to allow me to set ride height - mine was somewhat low and I preferred not to take the gamble on whether a new set of springs of unknown quality would reset the height.

Before starting, I made up some setting links; described only as JD.25 in the manual to check the rear camber and add/subtract shims to the driveshafts to adjust the camber. I found the measurement of 22.9cm or 9 1/32" on the internet, but they were hard to fit, I had to compress the car considerably to fit them - and this is starting with a car already low. When I had fitted them, the camber was -3 degrees LH and -3.25 degrees RH. To correct this, I need 8 shims LH and 9 shims RH. This seems rather a lot.

Could anything else affect the camber (measured with a castor/camber level), or is this normal/acceptable? I think there are already one or two shims per side - I haven't checked yet. Also, can anyone confirm the dimensions of the JD.25 tool - preferably by measuring an original?

Regards and Merry Christmas to all.

Simon.

[Shimmer1]

I have just set up my Series 1 4.2 open top E Type`s suspension and need reassuring.
I used the front and rear setting links, and I am thinking I should re shim the rear drive shafts (take out 1 per side) because the camber angle, with the setting links removed, is O/S -0.1 degree, N/S -0.2 degree. ( should be -0.75 +or - 0.25 of a degree). The setting links were fitted on the back with the aid of a small trolley jack chained to the cross beam and although portly I would be surprised if I compress the suspension to this extent.
My question, what is an acceptable camber angle without me and the setting links?
I used a Longacre Acculevel digital level and Gunson Steering Turntables.
Thanks in anticipation,
Shimmer.

[christopher storey]

You do not say what state the car is in i.e. does it have an engine or not ? Also, was it measured in the mid laden position i.e. with spare wheel, tools in the boot and half a tank of fuel. All of these will make a considerable difference to the results, so if you did not have them in placewhen you measured without the setting links I would have thought your results were acceptable

[Shimmer1]

Hi, The car is a runner with fuel, spare wheel, jack etc. when I checked the rear camber angles yesterday. Thanks for your reassuring comments. Its going in tomorrow to have the steering alignment checked and I`ll ask them to check the camber angles with me sitting in it.

[KingRichard]

HI,

When I measure camber at the rear I can get maximum of -0.25 degrees with all shims removed. That is with a half tank of fuel, spare etc. I don't use the setting links because I have to compress the rear of the car imo beyond what is actually happening when driving.

I also find my ride height at the rear about 1 inch to heigh. There was another thread about recently. Had to do with the length of the rear springs and shocks eye to eye measurement. My car rides fine, but can't compare with others.

Regards,
Richard

[Shimmer1]

I have had the car tracked and total toe was 16.7mm- much too high. It`s been adjusted to 1.6mm and when the weather improves I will take it for a run, it felt much better on the way home.
I think that using suspension setting links in a road ready car may be unwise as i`m now having to adjust the rear camber angles. Left is -0.2 degrees and Right is 0.0 degrees so N/S looses 2 shims and O/S looses 3 shims back to more or less where I started from!
The front is strangely OK at 0.5 and 0.3 degrees

[KingRichard]

Hi,

I'm interested in your findings. I like to know how steering wil be and particularly self centering after cornering. Mine does not self center al the way back as in a modern car.

Richard

[christopher storey]

Richard : have you fitted a replacement restored rack ? My experience of them is not encouraging . It seems that whoever restores them does not properly ream the replacement phosphor bronze bushes which produces "stiction" and gives precisely the symptom you describe of the steering running out of self-centring with the periphery of the wheel an inch or so away from the straight ahead position.

[jag68]

Chris - I'm just going through the bushing replacement saga on a steering rack I'm rebuilding. I had the bush reamed after installation but it's now just as sloppy as the old one and I need to start again from scratch - proving the old adage of doing it yourself if possible. In your opinion can you hone the bushing with a brake cylinder type hone as opposed to reaming? Seems like you might have better control with a hone.

[christopher storey]

I did in fact rebuild my rack on my fhc myself. I cannot remember exactly how I sized it, but since I do not have a variable size reamer, I think that I must have adopted your solution and honed it with abrasive cylinders mounted on a dremel type tool until I could slide it up and down the shaft of the rack with light force. I then , IIRC, immersed it in engine oil for a few days before finally reassembling the rack . I also drilled and tapped a hole on the left side of the rack ( my car is rhd and thus has the bush at that end ) and fitted a grease nipple so that I can squirt EP lubricant into this area directly

[KingRichard]

Hi Chris,

In fact, I didn't restore nothing on the rack, just gave it a good cleaning up. So I be very interested in the matter and what to do in rebuilding it.

Richard

Richard : have you fitted a replacement restored rack ? My experience of them is not encouraging . It seems that whoever restores them does not properly ream the replacement phosphor bronze bushes which produces "stiction" and gives precisely the symptom you describe of the steering running out of self-centring with the periphery of the wheel an inch or so away from the straight ahead position.

[jag68]

The extra grease nipple is a good idea. I'll copy that!

[Shimmer1]

Finally finished setting the car up. Now the tracking is correct its made all the difference, my confidence is back. It had been checked, by people who know what theyre doing, and found to be correct. Then I noticed the front upper wishbone ball joints were different, N/S nylon sealed for life, O/S standard ball and cup. I fitted a new N/S upper wishbone with ball and cup the toe in was 10 times what it should be after that. Putting it back to within limits made the difference. Can odd ball joints make this amount of error in the toe in?
Another point is I had the rear camber increased today and suggest one standard 0.020 shim alters the camber angle by 0.2 degrees not 0.25 degrees as in the book. No setting links were used for these adjustments.
Note, on page K15 of my manual it reads as if after the setting links are fitted the forward spring/damper assembly should be removed, in a state of compression, this can`t be correct or am I wrong?

[mgcjag]

Hi Iain......not the best writen instruction...but you would not do it as detailed .....the setting link is used just to measure the angle.....then removed to do the adjusting......Steve

[jag68]

Hi Iain I spent a few years setting up my own suspension on an E Type vintage race car that I had. I always set it as the car sat - not using the links that the manual recommends. I'd set the car statically with the driver's side .25 to .375" higher than the pax side so that when I sat in it it would be level. The setting links are designed to give you a consistent approach on cars where the ride height might differ due to age, damage, etc. from what Jaguar thought optimum. As you can appreciate as the car moves up and down on it's suspension camber front and rear changes (goes to negative as the wheel goes up) and front toe can change if the car has some bump steer in the suspension (I've never checked the stock suspension to see if there is any - if so I suspect it would be minimal.) All of this affects how straight the car steers while underway. What you are trying to achieve is more or less the same settings side to side in the normal ride height of the car as normally loaded when being driven. My experience is that most E Types sit low on the drivers side even without the driver in it. The springs and bars settle in due I suspect to years of driving with more weight on that side. It then sits even lower when you get in, specially if you are alone, giving more negative camber front and back on the low side. Having excessive camber on one side makes the car pull in the direction the tire is leaning to. If you had an adjustable torsion bar reaction tie plate, along with your fully adjustable Gaz rear shocks you can set the ride height all around, and level the car out under normal load/driving conditions. I use a Longacre caster and camber gauge with a magnetic base (part no 78260) that easily permits these measurements while the car in sitting on the floor - simply by removing the spinner and attaching the gauge to the hub that sticks out of the wire wheel. (As an aside: It used to be that alignment shops would put a little more negative camber (or less positive) in the far side front wheel so when the car is on a cambered road, for rain runoff, the car would steer straight.)

Another point. The settings that Jaguar suggest you use are for a car built in the 50/60's with bias ply tires. If you use radials you can increase the amount of static camber in the front from the positive suggested to a negative 1/2 to 3/4 degrees. This will significantly improve front end grip, without increasing wear (gets rid of some of the pronounced understeer stock E's display). Radials prefer negative camber. The rear camber specified at -3/4 degree is good. The toe in suggested by Jaguar works.

As to toe being affected by the new ball joint in the upper control arm - yes. If the ball joint is not in the same relative position to the center of the inner upper pivots on the attachment point with the car it pushes (say it's longer) the upright out at the top, which pulls the tie rod in, increasing toe in - for example. In other words, on your new control arm, the ball joint is not in the exact same position as the old ball joint relative to the chassis. Toe is affected by camber changes and castor changes made while aligning the car because it moves the ball joint in and out and backward and forward changing it's position, along with the upright and steering arm position, relative to the tie rod. Toe is always the last adjustment done.

[KingRichard]

Hi,

Can others confirm this statement as is correct or best practice nowadays. I never read it before that positive camber on the front can be altered to negative using modern tires. How about classic tyres such as Michelin XVS?

Richard

Another point. The settings that Jaguar suggest you use are for a car built in the 50/60's with bias ply tires. If you use radials you can increase the amount of static camber in the front from the positive suggested to a negative 1/2 to 3/4 degrees. This will significantly improve front end grip, without increasing wear (gets rid of some of the pronounced understeer stock E's display). Radials prefer negative camber. The rear camber specified at -3/4 degree is good. The toe in suggested by Jaguar works.

[PeterCrespin]

All suspension settings are a compromise. The advice is OK. If it feels good, goes well and doesn't shred tyres you're fine. You wouldn't want to drive a car optimised for autocross on the street but apart from that I wouldn't sweat it.