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In the next month or two I am going to seam weld the chassis in my car. Obviously first off I'll be removing all the sounds deadner before I begin to seam weld the engine bay, floor pan and boot area. Before I begin though I have a few questions for those experienced that have done it before.

- Does the car require to be lifted off the ground and if so is it critical that the car is completely level before seam welding?

- Would the car benifit from being under tension from strut brace towers and B pillar bars before welding?

Any one who can point me in the right direction and give me some tops would be appreciative.

Cheers,

Scotty

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From theory if the car is seam welded while under tension from adjustable strut braces (front/rear), tension rod (front suspension) and B pillar brace. The shell typically should be held in place once the car is seam welded and I guess would benefit from being on the ground as to add more tension to the chassis. The interior and boot will be welded with the motor in it to give it more realistic circumstances ie. having the weight of the motor on the car. Motor will be removed once this is done and seam welded seperately.

The cage that will be put in wont be a stressed member, so won't be in there while the car is being seam welded. It will probably be a 4 point half cage for the time being once the car is being sorted, with an additional 2 points, extending over the drivers head, through the firewall to the front strut towers once the car is further sorted (I don't like 6 point full cages with points located near the drivers foot). Considering having two of the rear points extending to the rear strut towers as well. This is just theory for the time being before I have a set direction I want to take with the car. Just wondering on how others have done it before I head off and do it myself.

Will be used for drifting btw. Recently obtained a R32 RB25DE motor which hopefully will convert to a RB30DET with a GT35R. Which I'll use in the car

Edited by Baz
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Well we found the rear strut towers easy to get to, nissan gave us holes in the rear bulkhead to go through. 1 bar between the c pillar/wheel wel lmeeting point and a second bar between the 2 strut towers like a strut brace. Then 2 bars to tie them together as a square. Triangle would be better of course if possible.

Front on the other hand is a disaster. Need to move the brake booster and ABS if you have it for a decent triangle to the struts. Or there is an option to run a bar in the inner guard to the front strut tower from the A pillar bars.

Be really careful with the cage design even if for drift. There is a school of thought within CAMS that having an unapproved cage is more dangerous than no cage at all - and they may ban cars with unapproved cages. At some stage that, together with someone noticing that drifters do get out of first gear (unlike motorkhanas) will end up having your car banned.

Main point for that is front cage legs must be at A piller and can only have 1 bend from the roof

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Interested to see your results.

Are you going to be running a oll cage? I personally wouldnt bother seam welding a car. Sure Skylines arent the most rigid things...but you will get a lot more out of a simple roll cage...it woudl increase rigidity but i would not think by a massive amount.

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You would be surprised by the amount of rigity that you would get by seam welding a car. It's something which many people really dont do. Due to the amount of work stripping out the car, removing the sound deadner and then getting access to a MIG welder to do the spot welding along the seams. It will be getting a roll cage but as Duncan said before its regardless of how you are at fabrication, if its not CAMS approved then you will basically be turned away from many tracks. This is why I've considered getting a bolt in jap half cage, may not be CAMS approved but they have some marking that I'm aware of that allows people to use them at the track. They are unfortunately only of 38mm thickness (I think) which is below the CAMS requirements for a cage.

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i know one of the ae86 drifters in perth, (i think it was ken) has seam welded his 86 may be worth getting incontact with him and asking him the question.

Yeah I've actually driven Ken's car before :( Thats where I originally got the idea from. The car was just so stiff and rigid and also insanely loud as well lol. The only difference is that I'll probably leave a lot of the interior inside the car, so that its still loud inside, but doesnt echo like Ken's car did. AFAIK Ken seam welded his car on a hoist. Was just curious how others have done it.

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Yeah I've actually driven Ken's car before :P Thats where I originally got the idea from. The car was just so stiff and rigid and also insanely loud as well lol. The only difference is that I'll probably leave a lot of the interior inside the car, so that its still loud inside, but doesnt echo like Ken's car did. AFAIK Ken seam welded his car on a hoist. Was just curious how others have done it.

not sure if this helps but i have an option special dvd which is all about ae86, on one of the dvd they have the WORK BOX ae86 buildup and when they do the seam welding on the ae86 its just on the floor on the rims (and i think at one stage it was just on axle stands)

Also a friend of mine with an red 86 coupe POP Rivets his car while it front half was on axle stands and the rear half on the rims. and that turn out awesome really stiff.

so i think you should be fine if you cant get it onto a hoist to do it

edit: http://www.v-opt.co.jp/86.html check out this link as it has some sample vids of the dvd hopfully got something on the seam welding or else if you want a copy of the dvd i can burn you one

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Would anyone know how much approx. to get a skyline seam welded? i am quite interested in $$$ amount as i have considered getting it done in the past, but was too lazy to do anything about it.

do it yourself its not a hard job, not sure what i workshop would charge you but im guessing it will be alot of coin because they will have to strip the whole inside of your car, also if you want the engine bay done they might have to take out the engine = big dollars for labour

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One peice of advice I got from a mechanic friend of mine who has seam welded up a few cars is do it symetrically, ie. do one spot on the left hand side of the car, then move to the exact same spot on the right hand side and spot there. Doing this stops the car twisting as one side tightens up while the other stays slack.

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ive seam welded a few cars for speedway made my own rotery frame to mount the shell on so you could spin it around . seam welding made a huge diffrence to cars there is a lot less flex even with a full roll cage the suspension actually gets a chance to do what it;s designed to do instead of been soaked up in chassis flex . also makes the car stronger in case of a a hit once we seam welded a chassis we actually had to change spring and shock rates it made a far nicer car to drive . i suspect it would be the same on a drift or circut car as well . imho it is well worth the time and effort

cheers mid life crisis

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