Well ive been looking into this for ages and have read many threads but have yet to actually see any where where the question has been answered.

I have a pair of R31 struts that i wish to use in my 140J
but i don't know what position to weld on the spring seats from my original shocks to give it a couple inch drop.

Im guessing i need to measure from the hub center to the top of the stock strut tube then add 2" to that measurement then measure from the top of the strut tube of the R31 strut and weld spring seat on there.

Will this be fine to do and use the factory springs? Reason i ask is if later i find the springs to soft i could just replace with factory replacement king springs etc.

My original plan was to put a hose clamp on the strut tube and put spring seat onto of that then assemble strut into car and loosen hose clamp off and then tighten it up once i found my desired height.

Reason i have decided to do this now is my mate is over from OZ and he is a qualified (tig welds for a living) Tig welder i was going to get him to do the job as i feel the tig will make a nicer job rather than my bro in law using the Mig which im worried will be to hot and distort or wreck the strut tube.
Or will the Mig be fine for doing the job???

How have others welded there spring seats to they strut tube
Tig?
Mig?

Any process i should be aware of?

Thanks
Brett

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Past:
A10 160J Coupe
R30 Turbo Manual
Present:
KP710 160JSSS Coupe (My Standard Car)
KP710 160JSSS Coupe (My SR20DET 6Spd Car)
KP710 140J Delux (New Road Car)
KP710 Parts POS

it depends what type/model of spring seat and spring you use as they will be different heights.
When i did it last, i mounted a rim with the right offset and biggish tyre (205/45/16) on the hub/strut and then brought the spring seat down as low as possible so the spring had less chance of binding up at full shock compression but still clear the tyre ok.
This worked out well with bump stop size too.
I used Datsun Sunny seats and springs (cut a coil or two but they are still captive).
Can get measurements and a pic if it helps.
Thats what i've got in the front of my brown car thats in my avatar...
p.s. i used gasless mig to weld the seats on the strut tube but anything would do really mig/tig/oxy etc.

Ah ok so the mig wouldn't be to hot and damage the strut?

The guy driving the mig is a qualified panel beater so he knows what hes doing. So maybe i'll just wait set all up in the car so i get it just right.

_________________
Past:
A10 160J Coupe
R30 Turbo Manual
Present:
KP710 160JSSS Coupe (My Standard Car)
KP710 160JSSS Coupe (My SR20DET 6Spd Car)
KP710 140J Delux (New Road Car)
KP710 Parts POS

mine were done with a mig too. I basically did the same as nick said. Worked out the lowest possible position which wouldnt foul on the tyre and then welded them on.

I'm doing this conversion with my 200B on Monday (originally two weeks ago but Supacrap didn't send the right springs and took a week to deliver shocks from adelaide).

I'm using R31 strut towers with r31 shock and 200B springs and spring cups. I was just planning on welding to the original spot (extra compression of the spring, I know)..

How much further have you gone down? I'll be measuring, but would like a rough guide

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Daily Drive: '80 200B GX Wagz
Soon to be: ... Supercharged? Can't ever decide..

If it's not broke, don't fix it.. Upgrade it!!!

just use an exhaust clamp under the spring saddle till you get the desired ride height.
Then jack up the car to make sure the spring is captive.

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I've not done it myself, but looking at the pics around and thinking it thru, I don't know that you've got that much room to move.
It can only go down so far before the spring seat would foul with the trye. Easy enough to check off the car, strut with a hub, sitting inside the intended tyre would define that position. If you start with the spring seat at the bottom of the thread in that position, I reckon you'll find the top of the collar goes within a bee's D!ck of the top of the strut. Most of the pics on the net seem to have the collar near level with the top of the strut.

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