Effects on geometry of lowering springs

[Mr Lazy]

Thank you all for the extra comments. @Beachbum957, your comments are very interesting. The H&Rs appeal to me if they aren't quite so low. The Koni inserts you mention, what exactly are they? Are they damping cartridges that fit inside standard struts or something? Is there a part number or name?

[Beachbum957]

We ran Tein-S springs for nearly 30,000 miles, but like the H&R better.

I am not sure who carries Koni in the UK, but you can start HERE

The Konis are inserts that go into modified stock struts.  The housings are cut, the original internals removed and the inserts installed.  They come with instructions, but you can probably get the instructions from any reseller to see what is involved.  Or you can search the forum for "Koni" or "Preparation for Koni inserts" to get more info. There are some differences of opinion on modifying the rear housings as far as how much to cut, but the forum threads cover the topic.

The part numbers are

Front 8641-1420SPORT (2 required)
Rear 8641-1422SPORT (2 required)

Or you can get the sport kit that should come with H&R springs and all 4 inserts

Sport Kit 1140-3991

[Gaz mr-s]

https://www.youtube.com/watch?v=PXSnNZt3NiI

Angle grinder makes it a lot simpler.

[Iain]

Running Eibach springs and new kyb struts, no complaints and not too low.

Eibachs are dearer, but imo, worth it.

[Ardent]

Toyota also sell bolts that have a shallower shank. So a bit more adjustment can be had.

[Petrus]

Toyota also sell bolts that have a shallower shank. So a bit more adjustment can be had.

a.k.a. crash bolts. Don´t know why.

[Ardent]

Am I missing something, or are you suggesting Toyota sell parts that are not fit for purpose.

I find it very hard to believe, they would sell a part that would not perform it's intended function.

[Mr Lazy]

I'm just coming back to this after a busy few days. Thanks again for all the additional advice. I'm not going to do anything just yet. I first want to get it MOTd and back on the road (hopefully within a week) and then refamiliarise  myself with the feel of the current stock setup before anything else. I'm most tempted with the Tein springs and KYB struts because they are tried and tested by lots of you, readily available, (hopefully) easy to fit and not too expensive. The Koni inserts seem like a good idea, but I'm not sure that I trust myself to modify the struts. H&R springs are appealing, but I have only found one stockist and they are quite a bit more expensive than the Teins.

Speaking of the Tein springs, the fronts and rears are advertised as having different lowering heights (29mm front, 33mm rear). Why would this be? I just want the car to be level. My only guess is that a slight nose up would help with speed bumps, but I'm not sure that it would really make much difference in practice.

I've also just noticed that unusually, MR2-Ben seem to have the best price for the KYBs at the moment. £69 fronts and £79 rears, including VAT but not delivery. Tempting.

[Ardent]

Unusual indeed.
Good price for kyb.

[Petrus]

Am I missing something, or are you suggesting Toyota sell parts that are not fit for purpose.

I find it very hard to believe, they would sell a part that would not perform it's intended function.

I am not, they are just called like that regardless of the brand.

[Topdownman]

I was always attracted to the teins because of the different drop heights. The reason for this is that the fronts sit higher than the rears as standard so a larger drop on the front makes the car look better.

Having recently fitted teins again, I do think the spring rate is too soft. I had eibachs on a previous car and thought they were great. I know of at least one other member who had teins and didnt like them so swopped for H&R and he loves them. I may well look at changing my springs at some stage.

I would look on ebay and find the kybs from places like parts in motion and car parts for less and save them in your watch list and wait for the quite frequent 20% off vouchers they do. Look at their own websites too as they can have offers there as well if you buy direct.

[Iain]

I was always attracted to the teins because of the different drop heights. The reason for this is that the fronts sit higher than the rears as standard so a larger drop on the front makes the car look better.

...but the teins lower the rear more. Or at least thats what it says on every website i looked at.

[Petrus]

...but the teins lower the rear more. Or at least thats what it says on every website i looked at.

Have a look at the comparative spring rate table.
The TRD springs uprate significantly different front/rear, whereas the after marketby and large follows the stock balance. TRD álso gives a slight rake (the front lower than the rear).

[Topdownman]

I was always attracted to the teins because of the different drop heights. The reason for this is that the fronts sit higher than the rears as standard so a larger drop on the front makes the car look better.

...but the teins lower the rear more. Or at least thats what it says on every website i looked at.

Just had a look and most websites do say that the drop is lower on the rear on most listings. Not sure I agree with them though!

I did find that monkey wrench racing list the bigger drop at the front;

mwr

It doesnt make any sense to drop the rear more so I think that the listings are wrong?

I would still personally recommend the eibachs or H&Rs over the teins though!

[Beachbum957]

Tein US lists the drop as -1.4" (-36) front and -1.2" (-31 mm) rear, but the springs are out of stock, and have been for some time. Info HERE. Tein global doesn't even seem to list the springs anymore.  We bought Tein springs 10 years ago, and the drop was a bit more than that, but the car was fairly level.

There are a couple issues with Tein S springs.  The front was lowered to the point it almost touched the stock front bump stops.  The early instructions show cutting the front bump stops .8", but apparently the later instructions don't mention it, so perhaps the front springs have changed. In either case, even with cut stops it didn't take a really hard bump to get into the front bump stops because of the reduced travel. Another problem was the significant number of counterfeit Tein springs at that time. Info HERE

Tein doesn't mention it, but the springs are dual rate and about the same rate as OEM initially, and then stiffer.  The spring rate listed in the documents is the stiffer rate for an unmounted spring.  Most of the softer rate is used up by the initial compression, so the rate in the normal travel range is the stiffer rate.

We ran the Tein springs for nearly 10 years with both KYB struts and Koni's and thought they were fine, until we tried the H&R. Now I would not go back to the Tein.  The H&R and Koni's is a very nicely matched package. There is a reason the Koni suspension kit sold in many markets comes with H&R springs.

I learned early to not put much confidence in advertised specs as they are often not entirely accurate.

[Iain]

I was always attracted to the teins because of the different drop heights. The reason for this is that the fronts sit higher than the rears as standard so a larger drop on the front makes the car look better.

...but the teins lower the rear more. Or at least thats what it says on every website i looked at.

It doesnt make any sense to drop the rear more so I think that the listings are wrong?

I would still personally recommend the eibachs or H&Rs over the teins though!

Yeah i dont get it either, i also thought surely the listings are wrong/backwards.

I read alot on here before i lowered mine as i fancied the teins but plenty of posts about it being too low and too soft put me off.

In the end went with the Eibachs as having used them on cars in the past i knew they were a quality product with proper research.

[Mr Lazy]

To clarify, the Tein UK website lists the springs as -29mm front and -33mm rear. See here: https://uk.tein.com/srch/uk_search.php?maker=TOYOTA&carmodel=MR-S&modelyear=1999-2007&item=default&genuine=0&tuvchk=0

You have to select MR-S rather than MR2 Spyder (there is no MR2 Roadster option) to get any spring info. So assuming the stock car sits level (which may not be the case) then this would give a slight nose up appearance.

[Beachbum957]

Fascinating, as Tein US and Tein UK list different part numbers, but the spring free length and spring rate is the same.  The chassis code on the US site is ZZW30L and the UK has ZZW30.  If would seem the UK and Europe uses different springs than North America.

The UK site for the MR2 Spyder (as it is called in the US) lists the coilover kit, which is NOT available in the US!

To add to the confusion, the cars sold in North America and the UK used the same OEM springs

[Ardent]

To clarify, the Tein UK website lists the springs as -29mm front and -33mm rear. See here: https://uk.tein.com/srch/uk_search.php?maker=TOYOTA&carmodel=MR-S&modelyear=1999-2007&item=default&genuine=0&tuvchk=0

You have to select MR-S rather than MR2 Spyder (there is no MR2 Roadster option) to get any spring info. So assuming the stock car sits level (which may not be the case) then this would give a slight nose up appearance.

For what it's worth. I am on kyb and teins. With a look through, what have you done  or the photo corner threads. Lots of pics of my car. I feel fairly sure it is not nose up.

[Dev]

To clarify, the Tein UK website lists the springs as -29mm front and -33mm rear. See here: https://uk.tein.com/srch/uk_search.php?maker=TOYOTA&carmodel=MR-S&modelyear=1999-2007&item=default&genuine=0&tuvchk=0

You have to select MR-S rather than MR2 Spyder (there is no MR2 Roadster option) to get any spring info. So assuming the stock car sits level (which may not be the case) then this would give a slight nose up appearance.

For what it's worth. I am on kyb and teins. With a look through, what have you done  or the photo corner threads. Lots of pics of my car. I feel fairly sure it is not nose up.

Everything that I have seen with the Teins in pictures and in person with the Tein S springs does not have the nose pointed up. I do not know which one it is but I recall one of the other three spring choices did have the appearance of the front higher than the rear which came from a very old discussion on Spyerchat that had pictures.
I have driven cars with the Tein S and Eibach combos and they felt the same to me which was limiting for my taste and much closer to the softness of the OEM.
The only suspension I felt was one of the best balanced was the Sportivo kit but that also included other parts of the suspension like matched swaybars however I still felt that I wanted more and I got exactly that.

[Iain]

The nose looking higher can also come down to alloy wheel sizes. Cars that have 16s on the rear and 15s on the front have about a 15mm height difference between the two on oem tyre sizes.

[Gaz mr-s]

I've also just noticed that unusually, MR2-Ben seem to have the best price for the KYBs at the moment. £69 fronts and £79 rears, including VAT but not delivery. Tempting.

If Paul at TCB has them, he'll be cheaper than MR2Ben.  I have never known them to be cheap on anything I looked for. More likely a 15 or 20% off on ebay is the cheapest.

There are cheap Teins on there at the mo' btw right now.

[Mr Lazy]

The nose looking higher can also come down to alloy wheel sizes. Cars that have 16s on the rear and 15s on the front have about a 15mm height difference between the two on oem tyre sizes.

Thinking about this, if aftermarket manufacturers supply the same springs for the pre and post facelift cars (as Tein do), then either the pre or post facelift car will always be slightly tilted, depending on which version the springs are optimised for.

[Dev]

The nose looking higher can also come down to alloy wheel sizes. Cars that have 16s on the rear and 15s on the front have about a 15mm height difference between the two on oem tyre sizes.

Thinking about this, if aftermarket manufacturers supply the same springs for the pre and post facelift cars (as Tein do), then either the pre or post facelift car will always be slightly tilted, depending on which version the springs are optimised for.

There were some slight changes to the springs I believe around 2004 for meet certain pedestrian safety standards in Canada for height. Otherwise the struts and springs for the aftermarket is the same for all years and should not make any difference.

[Petrus]

Speaking of effects on geometry....
Remember the discussions about the effects of the dog bones?
If one thinks thát confusing, try a sidecar.
Tried to explain sidecar geometry to Mounatin Girl and what happens when it is on the move. How the various forces always cause all three wheels to scrub, roll with a slip angle.
Too much different forces involved to remember in a virtual situation.
Just went down to the village for some proper drawing material (son took all with him).