Differents of coil springs of NA-Turbo

gemiz

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In Norway there is some rules regarding engine change of a vehicle.

If im gonna rebuild a NA to Turbo 1987 Supra MK3 i need to "change/make sure parts are the same" regarding: Engine, Brakes, Suspention and emitions".

When i go thru all of the parts of these elemets of a NA Manual and an Turbo Manual Targa/sport i have made a list of parts that is different.
Most is the same and some have different Toyota Part number.
The parts that have the same partnumber or is an part of the engine that i have changed is OK, its simple to document the change, the new parts and the parts that is the same.

My main problem is with Coil Springs, where there is a butch of Toyota Part number (non of what is possbile to order from Toyota today), and the springs i got from an 1987 Turbo have no visable part number.
So im not able to get my vihecle approved and get the plates.

The goverment have given me one possibility: buy a donor car and we will mark the parts and you can swap the over and get it approved.
I see this as a expensive and hard option (getting a donorcar is hard, not that many ruiend 7MGTE Supras to find) and its expensive.

The Toyota dealer says they are not able to help me as there is no new springs to get.

My wish/need: Some kind of documentation about springs and their spec that says a NA and Turbo is similar or the same, but different part number.
Or some where to get mint springs that i can buy.


Some fact, this is the part numbers for a NA car 1987 and a Turbo 1987 car, both manual, non TEMS:


NA - Springs Front Right 48131‑1B791 / 48131‑1D18
Turbo - Springs Front Right 48131‑1B791 / 48131‑1D150

NA - Springs Front Left 48131‑1B801 / 48131‑1D140
Turbo - Springs Front Left 48131‑1B801 / 48131‑1D160

NA - Springs rear48231‑14771 / 48231‑14820
Turbo - Springs rear48231‑14771 / 48231‑14820
 

Piratetip

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I seem to remember a topic like this coming up before.
Seems absurd to have to provide proof that the OEM springs are from the exact model it was supposed to have.

How can someone possibly proove the springs are correct?
You could swap them out from a donor vehicle but who is to say they weren't already swapped with another OEM spring at some point?
Are they going to remove the spring from the vehicle and test the spring free length and spring rates? Compare them to a table of OEM spring rates that do not exist?

You can pretty much count on the original part number tag no longer being present on the spring, if there ever was one.

FYI these are the spring rates listed for the European model Supra.
Comparing 1987 Turbo MT to 1987 N/A MT.
The same for models 88' and above.
There are a lot of PN's.

(Had to upload as image, the formatting was all messed up if I tried to paste it here.)



Toyodiy.com is a good site to look up these parts specific to European models.
(Or any other region for that matter)
 

gemiz

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Thanks for your post and i am i progress of searching for NEW springs with any of the partnumbers of an Turbo car.
My local shop sugested i might just get new springs made if i can get a hand on the spesifications for the springs.

Does anyone know where i might be able to get spesifications of the spirngs i need?
 

Piratetip

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Does anyone know where i might be able to get spesifications of the spirngs i need?
Find a set and measure them. (Free length, wired diameter, # of coils, measure spring rate)

What a spring manufacturer is going to need:
-Spec End Type (Closed & Square / Closed & Ground or Open End)
-OD
-ID
-# of Active Coils
-Wire Diameter
-Free Length
-Wire Material
-Stock springs have linear spring rates, not progressive

They will be able to calculate the spring rates based on the input dimensions.
Compare this against what you measure with the old springs to see how accurate the predicted is vs. actual.

Remember old springs may have lost some of their strength over the years.