Camber adjustment - Front ball joint & Upper wish bone

[Adrianw]

Hi,

I would appreciate any views on a current problem I have when adjusting the front offsite camber on the griffith.

I have recently fitted new upper front wishbones, the top ball joints are original or TVR parts as far as I can tell. When adjusting the camber the top ball joint fouls the wish joint, it does this regardless of which side the wedge spacer is fitted , but without the spacer there is clearly space for the balljoint to make a full range of adjustments. Looking at the arrangement my options appear to be fit some spaces on the leading edge of the ball joint plate (wedge at the back) to allow the front of the ball joint to clear the wishdone lip. The sensible thing to do would be to have be to have two wedges of half the width to go either side of the ball joint plate ? Has any done this or found perhaps found an alternative solutions ?


Thanks

[Pupp]

Many have had to grind away the wishbone material on the lip that fouls in order to achieve sensible camber. Seem to recall mention of some joints that were affected like this suffering failures so well worth taking time to ensure there's enough clearance all through the full range of movement. Changing the sandwich spacing will alter castor.

[carsy]

Clever Trevor sells the spacers in two halves, one either side of the ball joint. Everything should fit together perfectly then.

[BliarOut]

carsy said:

Clever Trevor sells the spacers in two halves, one either side of the ball joint. Everything should fit together perfectly then.

She'll turn in like a bd set up like that

My understanding is they've beefed up the design of the upper BJ over its lifespan. Just grind a little off the wishbone.

[DarkMatter]

BliarOut said:

carsy said:

Clever Trevor sells the spacers in two halves, one either side of the ball joint. Everything should fit together perfectly then.

She'll turn in like a bd set up like that

My understanding is they've beefed up the design of the upper BJ over its lifespan. Just grind a little off the wishbone.

I've recently fitted the SC-Power 2 piece spacers (6mm + 2mm). The car seems a bit twitchy now, although that could also be due to a change of springs and tyres. I'm going to grind a bit off the wishbone and re-fit the original spacers to see whether I can detect any difference.

If the OP is not aware the spacer (or larger spacer) goes on the leading edge of the balljoint.

[BliarOut]

Yup, that's the symptoms you get when you tweak the castor. Turns in bloody well though

[Adrianw]

Thanks for the advice.

The technican who set the car up yesterday said the front caster was spot on and would have to be adjusted if I used two spaces instead of one.

Front Rear
(Camber)
Left 0,10 -1,09
Right -1,28 -1,08

(Toe in)
Left 0,08 0,09
Right 0,07 0,08

Caster
Left 3,01
Right 3,47

As you can see the problem is that there is no adjustment on the left front with the maximum inward adjustment of the ball joint giving 0,10. I will have a look rounding off the wishbone edges, although the space option appears a better route.

(Sorry would have posted a picture but camera needs charging)

Cheers

[BliarOut]

Noooooo, don't spacer it, you'll feck the handling up!

Would you bend the headstock on a bike? That's effectively what you do if you alter the spacers.

[TVR Beaver]

Had to grind mine a tad.. (you can grind the split line on the ball joint also... but only use a round file.. no sharp corners... but they are well strong enough).. but don't change the spacers !

.

.

Edited by TVR Beaver on Sunday 12th June 21:44

[BliarOut]

high speed stability is iffy with equal spacers!

[Adrianw]

Thanks for the advice guys (Blairout/Quinny) and pictures (TVR Beaver).

I followed Quinny's excellent photo set on the removal of the front lower /upper wishbones (great bit of work, just unplayed the amount of effort getting the new one to fit)

Does anyone know what the factory caster settings should be ?

I don't really like grinding material off the wishbone, as with a dremmel one slip could be costly.
I did have grind the driver's spacer by 1-1.5mm ! just to get the original spacer & joint to fit back into the new wishbone. I have also noted that the wedges should be on the leading edge rather than the trailing one, which I have changed but with no difference in the ball joint movement range.

I like the idea of equal spacers as this seems a neat solution, as long can caster does get out of tolerance !

Unstable at high speeds should be the TVR motto !

[Pupp]

Not sure if it applied to Griffs too but original Chim figure was 4deg castor, with later cars (incl PAS models) at 4.75deg. Both within 0.4deg of each other

[Pupp]

Adrianw said:

I don't really like grinding material off the wishbone, as with a dremmel one slip could be costly.

A Dremel?

You'd need something a tad more manly than that!

[BliarOut]

You could spend five minutes with a full on grinding wheel and still have plenty of meat on the ends

[DarkMatter]

I've just ground a bit of my wishbones and have refitted the original 8mm spacers. I think it's better now, but having changed springs and tyres anyway it's difficult to be sure. I'll know more when I have had the suspension geometry checked/adjusted.

Information I have read from 'spend' is that castor should be 4.75 to 5.25 deg +ve.

[Adrianw]

The dremmel is okay if you want to do things in-situt, (I really don't want to take the wishbones out again !).

I have attached a print out of the alignment, interestlying the castor angle out of standard limits with the current 8mm spacers (3,01 & 3,47) , I assume these should be more like 4,00-> 5,00 ?
If so does this mean extra spacers are required or less ?

Thanks

[Adrianw]

sorry cut off the top of the image

[spend]

I think it all depends on the offset of the BJ's where you fit the spacers. Personally I'd always want over 5degs of caster, after experimenting years ago.. luckily I now have different wishbones so can set it easily enough.

I'd be getting the local motor factor to show you a range of Saab BJ's if I was you, and carefully measuring the BJ position on them to find the most suitable.

If the caster side to side has too great a divergence from each other, it does suggest something is bent BTW so be aware of that if you are making unequal adjustments to each side with shimming IYSWIM.

[DarkMatter]

I've just had a suspension geometry set-up on my Griffith using as a guide the following (I hope spend doesn't mind me quoting this from another thread)...

spend said:

Neill Anderson Once said:

Front & rear camber 0.75 to 1.25deg negative, as equal as possible side to side

Front tracking (toe) 10 to 20 minutes TOTAL ACROSS AXLE (5 to 10 minutes each wheel)

Rear tracking (toe) 4 to 6 minutes EACH WHEEL (as equal as possible side to side)

Front castor 4.75 to 5.25deg Positive (more important that each side is within 0.5deg of the other)

NOTE: As the front and rear wheel alignment are adjustable independently, but only the front wheels are connected to each other (by the rack) it is important that the pair of rear wheels are aligned to the nominal centreline of the car and not just to each other. The castor is not usually adjusted, the spacer at the upper ball joint is simply to ensure adequate clearance at the full extents of negative camber adjustment.

I now have the standard spacers on my car and the castor measured 5.5 deg on o/s and 6.0 deg on n/s which are both within 0.5 deg of each other but a bit more positive than the reference figure quoted above, but from what spend has just said that sounds like a good thing.

[spend]

DarkMatter said:

I've just had a suspension geometry set-up on my Griffith using as a guide the following (I hope spend doesn't mind me quoting this from another thread)...

spend said:

Neill Anderson Once said:

Front & rear camber 0.75 to 1.25deg negative, as equal as possible side to side

Front tracking (toe) 10 to 20 minutes TOTAL ACROSS AXLE (5 to 10 minutes each wheel)

Rear tracking (toe) 4 to 6 minutes EACH WHEEL (as equal as possible side to side)

Front castor 4.75 to 5.25deg Positive (more important that each side is within 0.5deg of the other)

NOTE: As the front and rear wheel alignment are adjustable independently, but only the front wheels are connected to each other (by the rack) it is important that the pair of rear wheels are aligned to the nominal centreline of the car and not just to each other. The castor is not usually adjusted, the spacer at the upper ball joint is simply to ensure adequate clearance at the full extents of negative camber adjustment.

I now have the standard spacers on my car and the castor measured 5.5 deg on o/s and 6.0 deg on n/s which are both within 0.5 deg of each other but a bit more positive than the reference figure quoted above, but from what spend has just said that sounds like a good thing.

No problem quoting they're just Neils figures, and I'll always stand by my opinion regarding higher caster angles

Basically I'd say have as much caster as you can muster the strength to steer with, whilst only downside increasing steering effort, it benefits bump steer, tramlining and cornering camber quite simply by 3d geometrical effects. When comparing cars don't overlook the fact that the chassis rake (ride heighters take note!) will also directly affect the caster angle whistle: