Front shock modification 101

All technical questions and answers regarding starions, being modifications to maintenance.
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MrBishi
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Front shock modification 101

Post by MrBishi »

I decided to upgrade from the stock widebody suspension for a couple of reasons. The main being the obvious improvement to the handling that comes from better shocks and heavier springs, while the second was to change from the stock spring seats to adjustable to gain greater clearance for bigger wheels and tyres and to lower the car. I own a widebody so this obviously applies to widebody (hereby designated WB) starions, but the Australian delivered Starions are very similar and the following will still work with slight variations. Unfortunately I don't have narrowbody (NB) suspension to check these details on and I'm hoping that any holes in the information can be filled by other members. Please feel free to add anything you think might help with the ultimate aim to create a complete resource for anyone thinking of upgrading the suspension on their Starion. My understanding is that the WB struts are longer than NB struts, but I'm not sure on specifics.

FRONT STRUTS
It's no secret that aftermarket bolt-in shocks are not freely available. Most that I am aware of need to be imported and it could be argued that they are a compromise to performance and more of a stock type shock. I am not aware of any adjustable shocks manufactured for the Starion (other than old SHP shocks). If we take the assumption that adapting a shock designed for another car as the best option then a huge range of shocks become availble - everything from cheap gas shocks for a daily driver to all out racing shocks for the most excessive starion on the track. I personally chose to use Koni adjustables as I have used them in the past and they are not a bad balance between performance and price.

My first take was to try and fit a shock into the stock strut body. The donor car that I settled on was commodore VB-VP front shocks. These will bolt into the WB starion strut body and the thread for the gland nut is the same. The only thing that needed modification was the spring top cap and strut tops due to a larger diameter thread. These shocks can also be modified to fit NB struts by grinding the knob off the base (see pic below). This modification was done and fitted to my JB many years ago.
The simplicity of the 'bolt-in' choice was soured by the fact that when sitting the car at my preferred ride height there was not enough travel to the bump stops, and the shock had too much travel to hold my springs captive (even with helper springs). Cue angry sounds from me at realisation that my new $600 shocks wouldn't work for me. However they would be fine for a daily driver at a sensible ride height and the slightly shorter NB struts would also help. I used these shocks in my JB for years and there was no problems with hitting bump stops and the lowered springs were captive.

The solution was to select a shorter shock. I had heard about MR2 shocks being used in the US and luckily Bodeo had a pair for sale that I purchased. Because they are shorter the strut body has to be cut and shut to suit, but I gained the benefit of more travel to bump stops and the springs would be captive. The added bonus is that the thread diameter at the top is the same as Starion so no further modifications required.


Part numbers;
Commodore VB-VP front 86-2076 SP1 (red adjustable) 8641-1066 sport (yellow adjustable)
MR2 SW20 2.0 t/c rear 8641-1221 sport (yellow adjustable)


Unknowns;
Are Commodore/MR2 shocks the same dimensionally between different shock manufacturers?
Are MR2 gland nuts threaded the same as Starion? The nuts didn't come with the shocks as I purchased second hand, and I can use the commodore ones. Will need to purchase some from koni to check (hopefully they will sell separately).


Shock comparison;
TOP - Koni yellow MR2 shock (my final choice)
Koni yellow Commodore shock
Koni red Commodore shock (as fitted to JB)
BOTTOM - stock widebody damper
Image

Commodore red vs yellow (note knob ground off on red to fit NB;
Image

Shortened MR2 equipped strut vs Stock length Commo equipped;
Image

Assembled front strut (needs repaint after cut'n'shut);
Image

Still to come;
Rear struts
Fitting adjustable spring sets, part numbers
Shortening strut tubes.
4G63 - 87kg
4G54 - 107kg
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WANTSOM
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Post by WANTSOM »

Anthony, just for reference info - the shocks in my track car (with coilover/adjustable springs seats) are Koni Yellows. After a bit of digging around by me and finally www.18U we found the shocks to be for a 300ZX. They fitted in the strut with only a wee bit of cutting to the overall length and dont need keeper springs. Thought you could add this to the databank for those considering coil over mod :beer
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MrBishi
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Post by MrBishi »

Can you get me some dimensions?
4G63 - 87kg
4G54 - 107kg
TommiCrazy
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Post by TommiCrazy »

I got question about suspension, very soon Iam goin to modify suspension of my starion (my galant was modified like that 5 yers ago, drop -50mm ) how much U can recomend to drop starion to improve handling , is there is any recomended setup? is this save to do -50mm??
with my galant standard suspension was modified in workshop, shocks was regenerated and shortered, and spring was hardened too , 5 years after no problems, so now I wanna do the same with starion.
Galant 2.0 E33A
Starion 2.0T Wide body
Galant 2.0T E39A 4WD
GTO 3.0 V6 Twin Turbo
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dirtygalant
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Post by dirtygalant »

Are you sure the thread diameter of the SW20 insert is the same as Starion? From the pics you posted, you can clearly see the SW20 insert has a wider thread at the top than Starion, and in addition I had to enlargen the strut top hole in order to fit my SW20 inserts on the rear of my Eterna (which has identical suspension to the Starion).

Also the gland nut supplied with the SW20 KYB inserts was definitely smaller than the Starion ones. Starion has 55mm OD strut tubes while Toyota is approx 51mm OD. I ended up getting a threaded section to suit the Toyota gland nut made up to weld on the top of my rear struts.
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jeff
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Post by jeff »

what welded on peices are those with the threads where can i get ?
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