chassis stiffening ke70

[love ke70]

hey guys, im currently rebuilding my 1ggte and reshelling it after having a chassis rail join spring itself apart on the last shell due to torque and mistreated rails.
so not wanting it to happen again im wondering what people do to strengthen and stiffen the chassis?
im pretty sure im gonna go road legal rollcage, but im not sure if thats gonna do enough when 300RWKW grips hard, i think its still gonna try flex the chassis like fuck.

so what do people do and who are the people to see regarding chassis rigidity and rollcages?

cheers, andrew

[The Real Roadrunner]

1G and torque should never be used in the same sentence unless the words "lack of" are used in between

for an e70 body i would strongly recomend some stich welding of all the front rails to the firewall / floorpan and to the inner guards / skirts also.
the rear will rquire some stiching of the rails to the floor / boot area also and probly another brace running from the panhard rod mount over to the opposite rail.

caging it would be good but a street legal cage generally wont add that much rigidity as you cant run many triangulated bars in them whilst remaining legal.

ill make my decision in the next 2 weeks as to what i plan on doing and ill give a full description then.

cheers
linden

[love ke70]

well, it had enough that you could feel the body twisting as it came on boost, and thats with half the power im gonna have with this new motor. so nerr

thanks for the response

is this the sort of thing your getting at with stitch welding?



obviously not a ke70, just using it so i know we are talking about the same thing.

what length weld would you suggest and what size gap?

if im gonna do this is probably worth my while to sandblast the underside while im getting the sills etc done isnt it? or would i be right to just grind?

hopefully this form of welding takes not alot of skill, coz i great at sticking thicker metals together with lots of welding rods, but never been good at the finer stuff, dodgy welder doesnt help, but the operator is just as bad

does this more stop the joins pulling apart, like it did last time, or actually increase chassis rigidity?

id love to see what you come up with for yours.

ive got to look into rollcages before i get too far into the body work, dont want them fucking my new paint so itll be happening while in primer.
the rules are 4 point rear weld in and bolt in front is it? and whats the limitation on triangulations?
i was hoping to get a midget to do it, and once he had trouble getting out, i woulda said i had enough there to keep me happy

thanks for the info thus far, and i know ill look back and realise i look like a tosser, but i gotta learn somewhere, and my workshop is sick of me taking up hours of time and spending no money

oh, last thing for now, is there any benefit to welding a C channel of sorts along the length of the rails? my boss (we are carpenters, so dont be too harsh) reckons its what used to be done to stiffen bodies up. but he comes from V8 holden background.


is the gap between front and rear rails an issue or is it strong enough the way it is? was wondering whether it would be worth adding plate above and welding the rails to it, so it ties it all together...


cheers, andrew

[The Real Roadrunner]

how soon are you planning on doing it? pictures speak a thousand words so id rather get this one done and just show you what we do to them.

im building both the drag one and the circuit car at the same time so you can choose either to base yours off.

you would have to look up the QLD regs as they are different to ours.

cheers
linden

[love ke70]

after tomorrow, sooner than next year. somewhere in between those 2 points im hoping
im not really in a rush, just got bored waiting for my bottom end to arrive, so im doing the body work first now, i just need to get this done before colour coat goes on, but that wont be for a while yet, plenty of body work to do still, and alot of other things to work out. just tryna work out what i need to do so i can plan it all.

im happy to wait to see the proper way to do things.

the plans for this car is all rounder, so it would prob be best to base it off the circuit one yeah? we will see once u get it done i guess

http://i29.photobucket.com/albums/c2...withcircle.jpg

if you go to that pic and zoom in, i have circled where the chassis rail was seperating and flexing like a bitch, and you can also see the attrocious condition of the chassis rails.

just so you can see what it is im worried about.

it is the join from bay to underfloor rails on the passenger side

cheers, andrew

[Mr Revhead]

dont forget to stiffen the centre of the car as well!
My KE70 wagon is developing some cracks in the B pillar area! :O

[crostek]

you could do this as well with the roll cage to stiffen up front



sorry for poor pic cameraphone

PS that is the same spot on my RA40 the chassis rails broke

[IN 05 NT]

what ive been told with stich welding is to keep the same gap, as the lenght of the weld,

ie a 20mm stitch, then leave a 20mm gap, then another 20mm stitch.....

you could also try making up another brace from the crossmember to the rails,

is the ke70 a full lenght chassis or like the celica where its missing under the middle floor? (cant think whets its called atm) but if it is you could make up the rest of the chassi and connect the front to rear.

also try expanda foam in the sills.

[oldcorollas]

how many time was it jacked up there? it looks like damage rather than twisting... ie the rail looks a bit crushed..

take a look at the whole picture.. work out what points in the car need strength (ie, where engine and suspension points are) and strengthen them and between them.. everything else is just there to hold up your seat and stop you getting wet

[love ke70]

you could do this as well with the roll cage to stiffen up front



sorry for poor pic cameraphone

PS that is the same spot on my RA40 the chassis rails broke

that is a very nice design and idea, and i guess the welded tower brace is feasable/legal, i do have a tower to tower bolt on brace already, and yes i could tell the difference with understeer with on/off.
with that design i think i should have enough clearance, but i would have to check, i may not be able to get the cam covers off with it setup like that.

the second picture, with the brace under where the dash goes, may also be possible, but would depend on what i can do with caging the front of the car, and the triangulated braces across the door opening is not legal, unless of course i keep it lower than the seat so as to not interfere with getting into the car. ie. not possible to be structural and road legal.

nice ideas, thanks

what ive been told with stich welding is to keep the same gap, as the lenght of the weld,

ie a 20mm stitch, then leave a 20mm gap, then another 20mm stitch.....

you could also try making up another brace from the crossmember to the rails,

is the ke70 a full lenght chassis or like the celica where its missing under the middle floor? (cant think whets its called atm) but if it is you could make up the rest of the chassi and connect the front to rear.

also try expanda foam in the sills.

thats what i read on my searching, but i wasnt sure how long to make the stitch...
from which crossmember to which rails? gearbox to chassis rails or something?

ke70 has a missing section about 100mm from memory, it misses a bit anyway...

would be difficult to connect it up without making underside sit very low, maybe welding something in above would help?

expanda foam is not going into my sills, imagine the rust...

how many time was it jacked up there? it looks like damage rather than twisting... ie the rail looks a bit crushed..

take a look at the whole picture.. work out what points in the car need strength (ie, where engine and suspension points are) and strengthen them and between them.. everything else is just there to hold up your seat and stop you getting wet

about 1 million, the rails were already looking shit when i got the car, looked like it had been dropped on the rail just behind where it seperated a few times, but it wasnt until i got it running and making decent power that it pulled apart, the front section that busted the welds did not actually have any damage, its the section behind that is damaged.

im pretty sure the chassis rails do not just hold up my seat through the centre of the car, im sre theyre meant to provide it some rigidity, which is what im trying to improve...

cheers, andrew

[Hack]

For the chassis rail joining bit, check out MWPs thread as linkeded to below...
(Photo warning etc...)

http://www.toymods.net/forums/showthread.php?t=17464

Not sure if the U channel is actualy cut into the floorpan or not.

Hack