benefits, legalities and evading the authorities surrounding seam welding your body

[dburto]

CAR - AE71 CSX

MOTOR - 4ac, soon to 20v 4AGE

USE - Daily, drift/grip

PROBLEM - I want to stiffen her up but i'm not sure what seams i should be welding (corolla specific) etc....

PERSONAL SITUATION - Im an experienced welder fabricator so i dont need to know how to set up the welder or anything... Im wanting to understand and get a good overall view of the benefits, legalities ways to evade the authorities (should they pull me over) surrounding seam welding..

hey ppl long time watcher, first time poster (that i can remember) just landed my first rolla and im after information plz help :thumbup:

[resol]

as far as benefits, pretty much anything anywhere in a rolla that stiffer is goin to be a bonus (as long as it doesnt add too much weight). a half cage made a huge difference to the handling of my rolla when i had it.

the main seams are the ones which are under the most stress, and connect to the more important parts of the car. i.e strut towers, wheel arch's and chasis. weld these to each other and you should get some positive gains from them.

i recomend searching through old scholl rally builds and such where this was done a lot and see what they did.

in reguards to legalities, if the engine bay is painted i challenge any cop to pick out that the bay has been seam welded. i dont think its illegal any way, just say you bought the car like that, and try to talk your way out of it if they pick it. i talked my way out of a weber carby, gatorade being used as a catch can, and twin tips poking about 1/2m out the back of the car. just depends who you talk to...


-dan

[tuned86]

Considered adding more meat to the chassis? This could help stiffen up the chassis without a rollcage. The mid section seems very weak and i've seen countless chassis bend at almost identical areas. One of the club86 videos shows bracing done on tsychia's car which seems like a good way considering he thrang'd his car alot. Here is an example of some1 doing the same, believe I saw it on the EU forums.

http://www.ae86drivingclub.com.au/dcimages/1/5/8/8/38503.jpg

[ke_70]

i eventually want to run rosejointed equal length rear end in my 86 track car and i think i read i'd have to seam weld the chassis is this correct?
would a full cage do the same job?

[dburto]

thanks for pointing in the correct direction fella's and ladies (is there any ladies on the forum in adelaide? i want my missus to join) had a bit of a rollie pollie today in the rolla so i will def be seam welding it and now more than likely fitting a half cage lol :)

i would like to hear more about ppls experiences with chassis stiffening aswell if there are more keen to share (maybe theres a kind old gentleman who likes rally cars on here who can help me)

[Rice86]

just use the N2 ae86 cars for examples, what they do and use has been proven to work

[NIZLAH]

Ive had my engine bay seam welded (Cheers Dimsum) and a half cage installed (and again) plus suspension completely redone since having my 86 off the road.... I cant comment on the improvements as I haven't driven it yet, but I suspect it will be in a whole new class than what I remember

[Sam-Q]

I really wonder how much of a difference seam welding makes, I don't think people give spot welds enough credit

[Rip it]

I really wonder how much of a difference seam welding makes, I don't think people give spot welds enough credit

Lots, the proof is in the pudding. People have been doing it for ever, in my previous and current gravel car you could notice the difference with the engine bay, strut towers and around the rails done.
Personally I think it's well worth doing, and you would never have any problems with the fuzz, as long as you re paint the welded area.

[Sam-Q]

yeah we all know it does something but I think it's more the icing on the cake than anything big, just my hunch anyway

[4000GT]

I seam welded my track car. Dont weld the entire seam, just spot welds at set intervals. You do this for may reasons including weight, ease of straightening after crash etc. Interval spot welds (according to my mechanical engineering mates) add around 30% to the strictures torsional and tensile strength. Very effective modification.

[KE70]

plus it looks cool haha

[ke70dave]

the other advantage of short welds is that if one weld cracks it doesnt proporgate through your entire seem weld.

pluss i think there might be some problems with warping your chassis if you weld along a seam for 20mins.

also you dont want to waste all that welding wire/gas since its not needed.

one inch of weld, 2 inches of space. is what id be aiming for. maybe a bit less dense on long seams, and a bit more dense in strut towers etc.

[4000GT]

I didnt weld for an inch personally, I went for 5-10mm. Dont have any data on why, but didnt want the weight. Even a spot is probably sufficient, but went a little further.

[ae71]

id recommend a strut bar at the front. it made a huge difference in my car. cheap, easy and quick upgrade. well worth it IMO.

gave a more procise feeling, better turn in and more solid mid corner feeling (maybe grip as well)

[Sam-Q]

I seam welded my track car. Dont weld the entire seam, just spot welds at set intervals. You do this for may reasons including weight, ease of straightening after crash etc. Interval spot welds (according to my mechanical engineering mates) add around 30% to the strictures torsional and tensile strength. Very effective modification.

if 30% is true then thats huge

I also would go for a 5mm long spot and then leave 20mm

[dburto]

i think i know what im gonna do now... i reckon im going to seam weld the whole she-bang, put the shock tower and chassis gusseting in as tuned86 suggested and i am definitely going to buy some of those ultra racing bars... this thing is gonna be mega stiff which is what i want... cheers for all the imput :thumbup:... i will be starting a build thread in the upcoming weeks so keep a look out
btw. her names Billy :cool:

[Sam-Q]

don't buy the Ultra racing bars! Buying strut braces isn't as straight forward as it looks. Their fender braces seem solid enough though.

[Sam-Q]

have a look at their poor attempt to make a brace,

http://www.ultraracingaustralia.com/USERIMAGES/AE86%20-%20FRONT%20ADJ.%20(2P).jpg

It has large angle bends and a centralised small diameter adjuster, this is what we call in engineering terms as stress raisers, the bar will want to flex at these points instead of providing the rigidity that is wanted. They are trying to save money by only have one adjuster and this means that the ends are not adjusted. The end design is actually quite good (much better than the T3 one) but they should of made the adjuster a larger diameter to reduce the potential flex through it, or change the deign to have it on one end.

Well at-least this product bolts into an area that's meant to actually do something unlike most of their products.

[ke_70]

they should of made it straight at least

[Sam-Q]

oh but then they couldn't use the same shape on about 40 other models...

this is why I hate this company, they don't give a shit about us modifiers, make it look right to the untrained eye and sell the thing already

[4000GT]

When doing your seam welding, make sure you do under the car as well... really many gains are had there by seam welding the chassis rails.

[--Redwork--]

Seeing as how this is a chassis stiffening discution I'll have to raise the offt neglected FOAM.

Alot of you guys have probably never heard of this but it basically involves filling all you internal areas of you cars chassis with high streght expanding foam...
Its is from what I understand MUCH more benificial to chassis rigidity than seam welding..
Plus you don't need a welder...Or worry about setting stuff on fire.... Only have to worry about the massive mess it creates. :)

[4000GT]

What are the physics behind it being much more beneficial than seam welding? Which benefits are you referring to?

[Sam-Q]

I have heard about this but I hear it's only good for areas that are likely to be kinked and I can't see that happening on any part of our cars, but hey happy to be proven wrong

[Ade_Mc]

http://www.youtube.com/watch?v=BHEdtAVlbBw


this may help


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