Rally Corollas

[rob83ke70]

we have a ke30 4 door sedan which is going to be built as a rally car... I'm in the process of stripping the weight out of it, and thinking about the roll cage. I was just after some pointers from people on here with 6 point cages and serious rally cars.

 

is there anywhere that needs extra reinforcement on a ke30 body? I know the strut towers need to be braced, as repeated khanacross races tends to bend the top of the strut towers causing camber and castor problems.

 

I was looking at making the roll cage myself, should I go with weld in or bolt in? any tricks as to getting complete welds on every join to meet cams approval?

 

We are running a modified 4k engine, so making everything as light as possible is a priority, although I'm juggling this with limited budget as well, so it should be interesting.

 

Robert.

[seabiscuit]

Keep us updated! (Rides thread) :)

[madKE35coupe]

are you planning on making the rollcage or buying a pre-made one? if you are planning on making one, i reckon the best thing to use is just your standard steel exhaust piping. easy to cut, bend and weld, but is pretty strong. at the tyre shop i used to work at, we used to mandrel bend exhausts, and they are pretty darn strong. and i think you can get 3m lengths for about 100 bucks? depending on who you get it from. and also, i reckon bolting not welding it in. that way if you do have any problems in the future, you don't have to butcher it to make any more modifications.

[KENut]

I vote weld in, for a stiffer cage and body.

I'd pay special attention to tying all suspension mounting points together with the cage, then making sure the mid section has minimal flex.

After that, think of actual crash protection, and working all these bits into each other for a safe, integral roll cage

[MRMOPARMAN]

are you planning on making the rollcage or buying a pre-made one? if you are planning on making one, i reckon the best thing to use is just your standard steel exhaust piping.

 

LOL. quoted so you can't change it.. :)

 

theres NO WAY exhaust tubing would be suitable for any sort of rollcage. if you can bend it by running into solid dirt at walking pace, imagine what hitting a tree at 100kmh+ would do to it.

 

rob, how much experience do you have with welding, bending etc. if your not excellent at it, your chances of meeting cams approval is pretty slim. my advice to you, if you wanna get it done as chaply as possible, buy a car already done. or maybe a rooted car with cage, cut the roof off both cars and transfer cage to good car.

 

goodluck, as other have said start a build thread and keep us updated. love the rally rollaz :P

Edited February 16, 2010 by MRMOPARMAN

[coln72]

Read the CAMS manual re. roll cage design. It specifies the minimum size of material to use and what material to make a roll cage from. Exhaust tube will not be acceptable.

 

Also make sure you build the cage to suit the regulations of the class you want to compete in as in some cases running the cage into the boot area and engine bay is banned.

[rob83ke70]

the thought of running the cage into bonnet or boot areas hadn't occured to me. I was after a minimal (lightest possible) cage, has to be a 6 point, and has to meet cams requirements, I have cams manuals here specifying what it is to me made out of.

 

I've got time up my sleeve for now.... but that being said the sooner it gets done the better. I'm planning on buying a pipe bender and a mig in the nearish future. I can mig weld to an ok standard, and I'm keen to do more and more to get to a better standard :) mild steel piping shouldn't be horrible anyway to work with.

 

the welds have to be all the way around each join, which apparently gets interesting when it goes in the car... someone said something about welding the cage in, if you drop it though holes in the floor and then weld it fully, put it back in position and weld plates/weld it to the body apparently it makes it easier.

 

I've got a few pics of the car that I'm going to have to get organised and upload. Kylie will be the chief driver of this vehicle, I get my kick out of building it, and I'm thinking of navigating when we get into rallies.....

 

The other thing on my mind at the moment is whether to run 13" rims with 175/70 tyres, or 14" rims with 185/60 tyres. We have a set of rally tyres that are 185/65 on 14" corona rims which we use for khanacrosses, which are just a smidge too big (they scrub at full lock). we run a bw diff with a 4.3 ratio at the moment, which is *just* low enough for the 14" wheels.... going to run a jap diff in the rally car though, and I'm thinking about ground clearance and suspension travel, as well as tyre availability and unsprung weight..... yet to make decisions, but I've still got a cage to stress about in the mean time.

 

LOL about the exhaust tubing.... I think it has to be a bit stronger than that...

 

Robert.

[Redwarf]

Have a look at mine:

 

http://www.rollaclub.com/board/index.php?s...1964&st=210

 

and my 25:

 

http://www.rollaclub.com/board/index.php?showtopic=366

 

Reading the CAMS ROPS regs is a must. 45mm cds and 38 mm cds are what is used, and are hard to bend. The main hoop needs to be as close to the pillars as you can get it and your standard of welding needs to be good. Welds as stated need to be full circumference. If you use exhaust tubing, I'll come and slap you personally myself.

 

I've worked as a motorsport fabricator, but I still get someone to build mine.

Edited February 16, 2010 by Redwarf

[rob83ke70]

oOoh brilliant!!

 

I hadn't actually thought about attacking the doors and the rear parcel shelf with a hole saw.... was going to take the trims off, the deadener out, and anything else I thought possible out. My battery is going to live in the back of the car where the back seat was unless I come up with a better idea as well. Distributes weight better and frees up space for cold air to go to the carbies, combined with heat wrap/ceramic coating, and heat shields I should have relatively cool air into my engine :)

 

thats a serious looking cage!! I like the idea of linking it to the strut towers. So you have it welded to the body at the six mounting points, plus at the top of each pillar, where else is it attached?

 

That is far more serious looking than what I originally had in mind.... I take it you were planning on crashing a lot harder/faster than we were?

 

Robert.

[rob83ke70]

the ke25 cage looks a bit more like what I had in mind....

[rob83ke70]

dumb question time:

 

This car is currently unregistered. We would like to put it on historic rego, which shouldn't be a huge drama as we are both in a car club that does this, and we have sorted out the requirements for that. The problem is the cage and the blueslip.

 

I'm assuming it needs to pass a blueslip to get the historic rego, and I need a 6 point cage to compete in rallies.... anybody been in this pickle before? what was the outcome?

 

Robert.

[corollaart]

If its your first rally car i would look at a bolt in ,because chances are you will have a excustion in to the forest at some time.

 

Not putting a mocker on you but ive seen it happen a lot.

 

Then with a bolt in at least you can transfer it to a new shell.

 

Weld in are the best but you need to get it done by a pro.

 

I think bonds bolt in are around 1300-1400 approx.A mate of mine just got his rex back from bonds ,weld in seam welded,plated etc 8500.

 

But it is a work of art .

 

I would strongly advise not to weld it in your self if you go that path ,because it will be a hassle when it comes to getting it logbooked.

 

I would seam weld strut towers add brace ,reinforce rear spring hangers as well ,then get out there have some fun .

 

rob

[altezzaclub]

We used to have bolt-ins mainly, because even if you don't crash it the shells are knackered after a year or so.

 

Make sure the foot plates have rounded corners, and if you weld them in don't weld the corners.

 

My cabbage designed my last cage (he was an engineering draughtsman) in small diameter thick-wall tube and we had an engineer approve it to get MANZ certification.

 

If you're not careful you will replace all the weight you're removing plus some! I think I've been rolled four times, and I've rolled once as driver, and we never had more than the very basic cage with one low horizontal anti-intrusion bar at floor level by each door. The only bit that did any work all those times was the hoop over the top of the windscreen.

[Andy43]

Rob

In speedway

We suffer from flexing strut towers and flexing top strut mounts.

We also get fatigue in the K frame where the lower control bolts go through, fix this with a 3mm plate welded over where the hole elongates and then redrill the hole.

Where the front of the leaf spring is welded to the subframe we get cracking there, weld a 3mm plate over the cracks.

I suspect our rear subframe was flexing around the rear of leaf spring hangers I have now reinforced this section as well.

Most speedway KE30's teams also have reinforced the front tiebar between the subframe arms, we have not done this but note our subframe did crack above the Kframe last sesson, Due to rules this crack was repaired with 1.6mm plate

The main part of our rollcage is 38mm x 3mm

Next off season we will be reshelling the old girl

Hope this helps

Andy

[snot35]

Go here for cage specs:

 

http://www.camsmanual.com.au/pdf/10_gen_re...dule_J_Q110.pdf

 

I'd also say bolt in to start. But do NOT go for the lightest possible cage if you're doing genuine rally. You want a decent amount of cross bracing and side impact protection. A decent cage will also ensure that your shell will last a decent amount of time and might even handle reasonably well depending on the cage. For seam welding you're probably going to want to do the majority of the shell in a Corolla, at least around chassis rails, strut towers and all suspension pickups.

 

Bolt in is good, because if you don't bend it every now and then, you're not trying :)

 

Also, don't hole saw the parcel shelf. As the fuel tank is in the boot you need a fire proof bulkhead separating the passenger compartment and the boot. If you chop it up you'll only have to fill it in later.

 

Here's some reading for you:

 

http://www.camsmanual.com.au/pdf/04_rally_...roup_3_Q110.pdf

 

http://www.camsmanual.com.au/pdf/04_rally_...-PRC_Q110_1.pdf

 

http://www.camsmanual.com.au/pdf/04_rally_..._Rally_Q110.pdf

 

http://www.camsmanual.com.au/pdf/04_rally_..._Rally_Q110.pdf

 

Pick your class, and have fun! :fuzz: