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Daniel-AE86
10th July 2005, 10:34 AM
The chassis is often overlooked in the restoration of a performance vehicle, with more attention paid to engine performance or cosmetic appearance. That can be a problem, because as every auto shop student knows, the chassis is the foundation of the car to which all other components attach and react. It holds the engine firmly in place, and supports the suspension, among other functions.

A chassis that is stiff will perform better than one that flexes easily due to road undulations, engine torque or hard cornering forces. Although it may seem unlikely for all that steel framework to flex, examples can be seen in the drag racing world, where it is not uncommon to see the chassis flex, lifting the left front wheel off of the ground due to the extreme engine torque. Another example is difficulty opening or closing a door on a car lifted up on a jack.

My question is, will it be worth welding a roll cage or re-weld chassie?, that is in the middle of two spot welds drill a hole and mig it.(mig plug)
Dont like the idea of driving around in a road registered car with a roll cage but if i have to i will.
Money is not an issue has i have a 161 mig, which will be for sale soon

DRiiFT_King
10th July 2005, 11:20 AM
if you have the time and skills its worth it, dont know about the roll cage, wouldnt you want to get a proper one, because we all know cusco is shit and that wouldnt be much better then a back yard job!

slide86
10th July 2005, 11:26 AM
you could pop rivet or spot weld as you say
but a welded in roll cage wil always be stiffer

decoyslikecurves
10th July 2005, 12:02 PM
Im pretty sure the cusco cages are worth what you pay for them. I cant see cusco making a product that is used by thousands of people in race conditions which doesn't work...

RobertoX
10th July 2005, 12:46 PM
^^ exactly

they are made to be lightish and easy to install hence bolt in, they seem to be good in jesses car

slide86
10th July 2005, 12:56 PM
yeah i have a saftey 21, 7 point roll cage.
very light, i havent put it in yet though

DRFTAE86
10th July 2005, 03:28 PM
For people interested: Heres a link to a Austrailan importer that can get cusco cages.

http://www.nissansilvia.com/forums/index.p...howtopic=100053 (http://www.nissansilvia.com/forums/index.php?showtopic=100053)

Daniel-AE86
10th July 2005, 09:18 PM
Ok, i came to a decision, im plug welding the hole chassie. Then ill take for a spin to see how she feels, if im still not happy, ill weld cage(I never said anything about aftermarket cages or spot welding http://www.ae86drivingclub.com.au/forums/emoticons/blink.gif )

slide86
10th July 2005, 09:44 PM
Originally posted by Daniel-AE86@Jul 10 2005, 08:18 PM
Ok, i came to a decision, im plug welding the hole chassie. Then ill take for a spin to see how she feels, if im still not happy, ill weld cage(I never said anything about aftermarket cages or spot welding http://www.ae86drivingclub.com.au/forums/emoticons/blink.gif )
ohhh i just assumed u ment spot welding when u said re-weld chassis
spot welding would strenthen the chassis alot
why not just do that when u go to weld it

The Doc
21st July 2005, 01:00 PM
If you really want a stiff car, I would suggest you seam weld your car first.
THEN you spot weld the other spots.
seam weld is always stronger than spot welding. As spot welding can crack easier under strong vibration. However seam welding will put more weight towards your car.

If you are really keen on stiffening up your sprinter, I would suggest you concentrate on the suspension mounting point, and the chasis rail.

However, its been proven that a sprinter without seam weld can do better time on track than one thats been welded up.

Joel-AE86
21st July 2005, 04:38 PM
Whatever you do, dont pop rivet the seams, weld them with a MIG or similar welder. ADD metal for strength, dont remove it.

A good example of a seam welded and braced hachi is the white SR20 Hachi in the member rides section (I think the thread is called 'abused').

DRFTAE86
21st July 2005, 04:58 PM
Originally posted by The Doc@Jul 21 2005, 12:00 PM
However, its been proven that a sprinter without seam weld can do better time on track than one thats been welded up.
Do u have a link or refrence source for this.....
I'd like to see. http://www.ae86drivingclub.com.au/forums/emoticons/smile.gif

Daniel-AE86
22nd July 2005, 10:38 PM
aparently theres an old ae86 club video that has tips on chassie stiffening, all in japanese but http://www.ae86drivingclub.com.au/forums/emoticons/sad.gif

I migth get a enginer to do this has i have just no time,

anyway this is what i covered so far

It would require: A heavy duty cycle welding machine as it will need a long duration of repeated triggering and welding.

Step 1: remove all interior trim, wire harness, and plastic item which may get damaged with high voltage, and extreme temperatures of melting metal. This is pretty much 'everything' in your interior down to metal floors, dashboards and stripping paint in locations the need welding.

Step 2:
For locations that have to be reinforced through two layers of metal sheets...that's 99% of an AE86 unibody structure. You need to drill holes through one layer for maximum contact and be filled (much resembling appearance and function of riveting)

Step 3:
Welding up these 500~1000 location spots along the body, Functional and Structural analysis should be made to selectively weld and sometimes reinforce the locations where rigidity is needed... That's basically the entire car too... Keiichi's car has 1700 spots and 22 points of structural reinforcements (OK DONT ASK ME WHERE...That would be a book to write...

In addition, the resulting body will drastically change in structural rigidity that alignment for suspension and spring and valving rates must all be modified to reflect on this and take advantage. It will feel though, better than when it rolled off the factory when it's all said and done.

slydar
22nd July 2005, 11:10 PM
my god. key board warrior.

DRFTAE86
22nd July 2005, 11:29 PM
1700 spots and 22 points of structural reinforcements...............



Fuk that!
Who here would seriously NEED that. http://www.ae86drivingclub.com.au/forums/emoticons/laugh.gif

Medwin_3sGTE_AE86
22nd July 2005, 11:39 PM
Welded up chassis definately feels better than one not welded up.... better control.... less flex.... and ur suspension will work better...

someone said an unwelded chassis will be faster than one not welded up.... i dont know where u got that from.... from what i've learned from race car dynamics seminars, stiff chassis is the basis of any good racing car... ideally minimal flex in the chassis so u can run softer springs to maximise traction. U need a stiff chassis to maintain all ur suspension geometry... not to mention a hard thrashed car often bends chassis... cuz factory cars were not designed to use high grip tires for racing... or drifting for that matter...

Only thing i can think of is the extra weight... but that weight is well worth it in my opinion... u can lose other shit for weight loss...

Daniel-AE86
22nd July 2005, 11:56 PM
Originally posted by The Doc@Jul 25 2005, 06:00 AM
However, its been proven that a sprinter without seam weld can do better time on track than one thats been welded up.
Dude, go back to your cave. Drifting is the worst strain you can put on a car.

Turbokid
23rd July 2005, 01:06 PM
It's also one of the most fun things you can do in a car.

If I was as elite as you, I'd build a cage and weld it in. Forget seam welding, if you ding it your f*cked.

Daniel-AE86
23rd July 2005, 01:28 PM
kid, most cages are build for protection only
ding it??, you mean hitting a wall or another car pretty hard? not really