Adjustable Front Spring heights?

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zetec311
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Adjustable Front Spring heights?

Post by zetec311 » Tue Jun 12, 2018 4:30 pm

hello,

ive been reading up on different suspension set ups. looks as if standard coil overs with threaded shock bodies are a no-no on a stock roadster suspension arms, has anybody had any luck with adjustable suspension cups?

Threaded tube with adjustable collars that are not attached to the shock body. Ive seen it for a ford focus, where the rear shocks are mounted in another location away from the springs. To adjust the height, one of those devices are used.

I can imagine if the spring is not under constant tension, the set up can shift positions if unloaded, since a shorter spring is used.

zetec311
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Re: Adjustable Front Spring heights?

Post by zetec311 » Tue Jun 12, 2018 4:48 pm

oh, found a video on youtube.. maybe would clear up what i was trying to explain..

https://youtu.be/5ayTgBT0uLw

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Alvin
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Re: Adjustable Front Spring heights?

Post by Alvin » Tue Jun 12, 2018 5:09 pm

zetec311 wrote:
Tue Jun 12, 2018 4:30 pm
looks as if standard coil overs with threaded shock bodies are a no-no on a stock roadster suspension arms,
stock a-arms
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troyt
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Re: Adjustable Front Spring heights?

Post by troyt » Tue Jun 12, 2018 6:57 pm

Alvin just broke the internet ;-)
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zetec311
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Re: Adjustable Front Spring heights?

Post by zetec311 » Tue Jun 12, 2018 11:44 pm

ooohhh! those are regular coil overs..

harsh ride on my car.. datsunparts springs with kyb gas-a-justs. feels very bumpy and very unsettled over uneven roads. i think the shocks may be leaking but they look okay. the oem bump stops have been trimmed down per somebody’s suggestion a few months ago.. no difference.

anyways, any tips or pointers for your set up? my guess would be a custom built shock but the koni stickers suggest otherwise.

JT68
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Re: Adjustable Front Spring heights?

Post by JT68 » Wed Jun 13, 2018 6:34 am

zetec311 wrote:
Tue Jun 12, 2018 11:44 pm
ooohhh! those are regular coil overs..

harsh ride on my car.. datsunparts springs with kyb gas-a-justs. feels very bumpy and very unsettled over uneven roads. i think the shocks may be leaking but they look okay. the oem bump stops have been trimmed down per somebody’s suggestion a few months ago.. no difference.

anyways, any tips or pointers for your set up? my guess would be a custom built shock but the koni stickers suggest otherwise.
Common complaint. Here are some tips (well proven):

1. A shorter, higher spring rate (even higher than the DP springs) is exactly the wrong direction.
2. Unless you are building a track car and want to run heim joint tie rods, if you lower the car to the point that requires heim joints, you will have dorked the suspension geometry completely for a street car.
3. There is no "off the shelf" shock for another car that will correct the problems you are describing- that is why folks go to great lengths to recalibrate Bilsteins and Konis.
4. If you make the front suspension lower and stiffer you will simply compound your problem.


A simple mechanical analog to illustrate the point would be if you replaced the tires with solid rubber ( a further increase in total spring rate) the roadster is so light it would skitter and bounce like a superball...

Word to the wise...
JT
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Gregs672000
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Re: Adjustable Front Spring heights?

Post by Gregs672000 » Wed Jun 13, 2018 11:53 am

Drove my car yesterday on some ugly roads. Marvelled at the JT Bilstiens, again. No, it's not the "bumps are of no issue" like in the 2001 Z3, but it is soooooooo much better than before. It's a vintage, comp suspension. You're gonna feel the road... I want to. I've had KYB's in all versions for Roadsters, revalved Koni, and now the Bs. With all due respect to everyone who has worked on shock options, revalving etc for us... thank you, but don't waste your time on anything else but the Bs. I drove over a spot near my old house yesterday and automatically cringed, expecting the big bang I used to get... no more. My wife and I looked at each other with that "Oh, not what I expected" look. From all aspects, these shocks really helped to transform the driving experience without taking anything away. For my driving (blasting curving, mountain roads) it does everything better, period. Thanks JT.
Greg Burrows
'67 2000 #588
Tacoma, WA

zetec311
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Re: Adjustable Front Spring heights?

Post by zetec311 » Wed Jun 13, 2018 1:47 pm

thank you for the info. its all about the B’s... lol

zetec311
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Re: Adjustable Front Spring heights?

Post by zetec311 » Wed Aug 29, 2018 4:28 pm

Some updates on my suspension...

My “fresh” kyb gas-a-just looked about 20 years old.. were painted white with spray paint and seized up. Sort of explains why my car bounces over parkinglot speed bumps at low speeds. Now the rear gasajusts were painted white as well, just the lower 1/3’s so they looked new.. but once removed, most of the travel dissapeared. Effective travel of only a few inches.. 14” compressed and 18” extended.. other side was 16”-18” respectively.

so saggy leaf springs, blown old shocks... things need to be freshed up a little. Not being able to upgrade to top-notch items at the moment... something more budget friendly for me.

I am running mini truck shocks up front.. about $40 each, they fit and theres no bounce anymore. Short stroked and made for lowered rides and high rated springs. Not performance oriented but at least they wont blow out if i decide to lower even more.

The rears are now inverted Tokico blues and “band-aid” saggy leafs with helper springs bolted on for the time being. The ride is terrible and out of control with bump steer at high speeds. At a recent cars n coffee, Ray did an inspection and found the rear dampeners not working right with a bounce test... he looks underneath and says your shocks are upside down. It turns out twin tube shocks cannot be ran upside down. The gas ends up in the wrong places and you lose a few inches of dampening.

I recall inverted bilsteins being okay to run in the rear (dont mean to drag up an old thread or throw sparks) The bilsteins in question are a monotube design.. totally different from what i chose. So twin tubes are a no-no, some monotubes are okay.. non gas shocks maybe. Costed me about $25 for NOS tokico.

I think the old Gas-a-Just can be covered on the life time warranty. Not sure if its worth the effort to chase down. Has anybody tried?

Anyways.. i ordered the KYB excel G’s for the Rear. I am prepared to be underwhelmed by it.