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-   -   Camber adjustment using strut body bolts (https://www.ft86club.com/forums/showthread.php?t=143712)

Plumbus 12-29-2020 03:24 AM

Camber adjustment using strut body bolts
 
As an aside to my top hat thread, my HKS max iv SP front coilover struts come with a slightly eccentric (or slotted/oval) shaped top hole for the knuckle bolts. This means I can pivot the strut around the bottom bolt, which has a round hole, and tune camber this way.

The strut body is currently set away from the car, reducing negative camber and alleviating the angle of the top sway bar link and keeping it at a somewhat safe distance from the frame. My question is, assuming I don't want to max out camber using both methods, which position is best for the strut body using the slotted hole? Which would you max first?

https://i.imgur.com/cn5DRl8.jpg

Racenut 12-29-2020 04:30 AM

On mine, I wasn't going to get the negative camber I wanted unless I pushed it in at the hub. But I have a different brand of coilover so maybe that's not the case for you. Which way gives you the best range of adjustment with the top hats?

Also, I wish mine was as clean as yours lol. The only thing shiny under my wheel wells is the new parts.

marco_mc22 12-29-2020 10:34 AM

If you don’t need other adjustments and keep the top plate in stock SAI/camber position I would keep the knuckle outside, less camber but less positive scrub radius, anyway this should not hurt as much as SAI does, then you can also turn the top plate 45 degrees and adjust both camber and caster, this should balance better the increased SAI with better scrub.
On mine with both methods maxed out I’ve got - 3 degrees of camber and +7 of castor but with kw slotted hole and adjustable links.

NoHaveMSG 12-29-2020 12:25 PM

Is your wheel turned in that picture? That sway bar end link is at a ridiculous angle if it isn't.

This platform is not really sensitive to SAI changes, we have had this argument on the forum a lot over the years. Here is a thread detailing it.

https://www.ft86club.com/forums/showthread.php?t=48107

marco_mc22 12-29-2020 02:36 PM

Quote:

Originally Posted by NoHaveMSG (Post 3396323)
Is your wheel turned in that picture? That sway bar end link is at a ridiculous angle if it isn't.

This platform is not really sensitive to SAI changes, we have had this argument on the forum a lot over the years. Here is a thread detailing it.

https://www.ft86club.com/forums/showthread.php?t=48107

Very nice topic, I honestly thought increased SAI has way more effect from other McPherson platforms, anyway increased Caster seems to be very beneficial so I think if you can achieve your camber spec with the plates turned is still better than the standard position right? :thumbsup:

NoHaveMSG 12-29-2020 02:55 PM

Quote:

Originally Posted by marco_mc22 (Post 3396351)
Very nice topic, I honestly thought increased SAI has way more effect from other McPherson platforms, anyway increased Caster seems to be very beneficial so I think if you can achieve your camber spec with the plates turned is still better than the standard position right? :thumbsup:

I did too for a long time too.

I don't know how much of an issue it is in the newer cars, but on the older cars like mine you can overheat the electric power steering. Increased caster is harder on the EPS. So you may want to experiment with it but with more caster you may run into a limit on what the EPS will handle.

ZDan 12-29-2020 03:00 PM

Quote:

Originally Posted by marco_mc22 (Post 3396351)
Caster seems to be very beneficial so I think if you can achieve your camber spec with the plates turned is still better than the standard position right? :thumbsup:

You can't rotate the camber plates 45 degrees, you have to rotate 60 degrees. Maybe not the end of the world, but ties your camber adjustment to caster adjustment where you might want them independent. These cars are usually a little asymmetric, so you might be stuck between having even caster left/right, or even camber, but not both...

I think big caster is hugely overrated. I've never been a fan of it since the days of driving my home-brew supension-modded 240Z unbeknownst to me put me at less than 3 degrees caster, and I loved it! Then I was stuck with more than 8 degrees with my 987.2 Cayman and I hated it...
I got the Raceseng cascam (caster/camber) plates, but found that they are designed so that the *minimum* end of the caster range is about stock or 6.5 degrees (though I'd have preferred 5.5). Which is fine w/ me except that one time the shop instead set them to *max* caster...

THe couple of things caster does for you *sound* good: More camber with steering angle, and some corner-jacking with steering angle acting to unload the outside front. Both these effects should give more front-end grip. But the balance will change depending on how fast the corner is, and you may get unwanted geometry change while sawing at the wheel at the limit. Because with more caster you have more changes in camber and weight-jacking with more steering angle.

If I *specifically* wanted more front-end bite at the lowest-speed corner and maybe less for the higher-speed corners, I *might* address that with more caster.

But personally I've never liked the feel of a lot of caster. Feels like artificial weighting to me, that corrupts feel at the steering wheel. My impression anyway...

strat61caster 12-29-2020 03:13 PM

Max bolts, fine tune with camber plates.
I like to keep the plates even so I can diy adjust as necessary away from an alignment rack so the bolts may not be fully maxed to make the camber the same l/r

marco_mc22 12-29-2020 03:29 PM

Quote:

Originally Posted by ZDan (Post 3396359)
You can't rotate the camber plates 45 degrees, you have to rotate 60 degrees. Maybe not the end of the world, but ties your camber adjustment to caster adjustment where you might want them independent. These cars are usually a little asymmetric, so you might be stuck between having even caster left/right, or even camber, but not both...

I think big caster is hugely overrated. I've never been a fan of it since the days of driving my home-brew supension-modded 240Z unbeknownst to me put me at less than 3 degrees caster, and I loved it! Then I was stuck with more than 8 degrees with my 987.2 Cayman and I hated it...
I got the Raceseng cascam (caster/camber) plates, but found that they are designed so that the *minimum* end of the caster range is about stock or 6.5 degrees (though I'd have preferred 5.5). Which is fine w/ me except that one time the shop instead set them to *max* caster...

THe couple of things caster does for you *sound* good: More camber with steering angle, and some corner-jacking with steering angle acting to unload the outside front. Both these effects should give more front-end grip. But the balance will change depending on how fast the corner is, and you may get unwanted geometry change while sawing at the wheel at the limit. Because with more caster you have more changes in camber and weight-jacking with more steering angle.

If I *specifically* wanted more front-end bite at the lowest-speed corner and maybe less for the higher-speed corners, I *might* address that with more caster.

But personally I've never liked the feel of a lot of caster. Feels like artificial weighting to me, that corrupts feel at the steering wheel. My impression anyway...

Yeah I mean with the plates turned 60 degrees, had mine like that and as you said camber is a little bit uneven but nothing terrible. Really appreciate your feedback though, maybe I can try the opposite, hub maxed out outside and plates maxed out inside so, lot of SAI, way less scrub and I think a little higher roll center as well, what do you think?

ZDan 12-29-2020 04:14 PM

Quote:

Originally Posted by marco_mc22 (Post 3396366)
Yeah I mean with the plates turned 60 degrees, had mine like that and as you said camber is a little bit uneven but nothing terrible. Really appreciate your feedback though, maybe I can try the opposite, hub maxed out outside and plates maxed out inside so, lot of SAI, way less scrub and I think a little higher roll center as well, what do you think?

You could *try* that, or maybe try both extremes and see how they compare? I don't have camber bolts and couldn't get much from them anyway due to stock-diameter springs and 17x9s with 245s... So all my camber is from the plates. Probably more conservative to kinda split the difference? If I had a solid opinion on this I'd share it, but I don't!

Plumbus 12-29-2020 05:22 PM

Quote:

Originally Posted by Racenut (Post 3396286)
On mine, I wasn't going to get the negative camber I wanted unless I pushed it in at the hub. But I have a different brand of coilover so maybe that's not the case for you. Which way gives you the best range of adjustment with the top hats?

Also, I wish mine was as clean as yours lol. The only thing shiny under my wheel wells is the new parts.

I believe the SP can achieve -3 on it's own. Slotted hole offers very little adjustment, but I'm still curious about the relation between the two methods.

Quote:

Originally Posted by marco_mc22 (Post 3396307)
If you don’t need other adjustments and keep the top plate in stock SAI/camber position I would keep the knuckle outside, less camber but less positive scrub radius, anyway this should not hurt as much as SAI does, then you can also turn the top plate 45 degrees and adjust both camber and caster, this should balance better the increased SAI with better scrub.
On mine with both methods maxed out I’ve got - 3 degrees of camber and +7 of castor but with kw slotted hole and adjustable links.

Not really interested in turning top plate around for caster adjustability. The slotted hole on the HKS is not super huge, you can probably get .5 degree adjustability at most. probably used for fine tuning more than maximizing camber I imagine.

Quote:

Originally Posted by NoHaveMSG (Post 3396323)
Is your wheel turned in that picture? That sway bar end link is at a ridiculous angle if it isn't.

This platform is not really sensitive to SAI changes, we have had this argument on the forum a lot over the years. Here is a thread detailing it.

https://www.ft86club.com/forums/showthread.php?t=48107

Yes it is turned to the right. Not sure if the included end links will be good after I lower to 1.3" from stock...

Quote:

Originally Posted by strat61caster (Post 3396362)
Max bolts, fine tune with camber plates.
I like to keep the plates even so I can diy adjust as necessary away from an alignment rack so the bolts may not be fully maxed to make the camber the same l/r

If I understand correctly, you told your alignment guy to set camber plates even and then fine tune with slotted hole so you can adjust the camber plates later without need for alignment? That sounds perfect, I may ask my alignment guy for the same. Hopefully the difference in SAI/scrub is not too bad between L/R with the slotted holes adjusted. I'm curious, why do you suggest the opposite of what you do though?

strat61caster 12-29-2020 07:03 PM

Quote:

Originally Posted by Plumbus (Post 3396408)
I'm curious, why do you suggest the opposite of what you do though?

I didn't. potay-toe potah-toe same effect, camber bolts are maxed evenly with camber plates even as opposed to camber bolts maxed unevenly with uneven camber plates to compensate.
sai/whatever, odds are your aftermarket suspension has looser tolerances then the oe knuckle/chassis and adjusting the bolts evenly should get you well within margin of error and the biggest change you'll see is uneven caster because the top mounts are kinda cheap.

HaXx 12-30-2020 02:03 AM

Dude I'm 50% certain you put your front coils on the wrong side. Your endlink should not look like that, be that slanted. Mine are perfectly vertical.

Racenut 12-30-2020 03:46 AM

Quote:

Originally Posted by HaXx (Post 3396526)
Dude I'm 50% certain you put your front coils on the wrong side. Your endlink should not look like that, be that slanted. Mine are perfectly vertical.

Yeah it looks wrong but I think the steering is just turned to the right. Seems odd they would decide to tie the sway bar to a steering part, but that's what they did.


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