Cage build choice?

[a_ahmed]

Anyone have more pictures of koguchi's cage?

I am liking the way he designed his cage, everything triangulated from what I'm seeing, a lil better than the typical loop, I was just wondering what you guys think and if anyone has more pictures of his car's interior so I can see more.

I know he also has front strut tower bracing to the firewall which is very nicely done too. I like overall what he's done with his car's chassis








Need to get this sorted out so I have a process plan and references when I go into the shop that'll be working on the car... I already miss my car... I feel like putting koni yellows on my winter beater lol

[sr20goofus]

gross....that cage/rollbar design is terrible.

[a_ahmed]

Is it? Cause honestly he has it triangulated and all the points connected from the way im looking at it. As opposed to having one point bombared with many bars over and over again? Carefully follow the triangles he has formed. I would take a triangle over ever many squares which is typically found in most cages I see with lots of bars... If that makes sense to me at least it does... Triangle is stronger than a square. At first I though it was a mess, incomplete, messy/complicated... but then I took a better look at it and followed how he triangulated... Can't really draw real-time to show what I mean... Plus the whole front and rear he has gusseted connected to chassis... and the front he has a bar connecting on an angle the pillars and roof... and in the center the center of the chassis/tunnel of the car which most cages don't do... essentially then making the whole rear completely connected and triangulated, very rigid, or I'm just not getting it then I don't know.. but that's what I'm seeing. Not a typical s chassis cage...

[jmauld]

Where's the harness bar?

That upper rear shock mount is interesting. Is that being used to adjust ride height without crawling under the car?

[a_ahmed]

Yeah that's the only thing I was wondering, where's the harness bar lol...

I'm not too sure, someone might be able to chime in on that. His new car (same chassis as you can see but red outside paint) is missing that. It's on his old black car (2001?)

His older green car (same chassis again just different state and green heh):

http://www.youtube.com/watch?v=Mosqy8LcVn0

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

http://www.youtube.com/watch?v=-dbUVJ5AN_Q

His current car is absolutely amazing:

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

http://www.youtube.com/watch?v=2ZsNfdAZUkU

[McCoy]

Your over thinking things here, a_ahmed. Most cages built for any race series/general club use have a fairly similiar look to them... what you posted up there doesn't rememble any of those...

Take Andy's pictures as a good starting point for a cage. Add the front 1/2 of the cage if you want a full cage...

http://nissanroadracing.com/vbulletin/showthread.php?t=182

One of the shots I stole from his link...

[sr20goofus]

things are triangulated in weird places, and the huge lack of real door bars and a harnessbar bothers me. I am a huge fan of simple, effective, and well designed. It seems you want something different from the ordinary when the ordinary is proven and safe.

Gussetts are not necessary and usually a well designed cage shouldnt need them, its filler for poor fitting cages. I will get some pics togeather of a solid cage that is legal for World Challenge cars and you can do a visual comparison. I would trust any WC cage over every single drifters cage, i have seen too much that scares me silly to trust anything from that "motorsport".

[jmauld]

Also notice the number of attachment points that cage has. There are some classes that limit the number to 6 or 8. Don't know if that concerns you.

[Def]

That first cage is horrible. A hit on the upper left part of the main hoop and the thing will bend with very little resistance. The whole point of triangulation isn't just randomly making triangles like he did, but to direct the load paths down to well reinforced nodes.

[ecugrad]

WOW, Im gonna guess that cage builder was getting paid by the foot of tubing used.

[a_ahmed]

^lol

sr20goofus can you post some pix of WC cages? I'm just curious to see what you're talking about.

I've asked Jon of momentumgt to show me how they did their cages, he's suppose to send me some pics of their car. It was a 2006 redline time/srx attack champ so will see. They were placing 1st and 2nd in ST2. Had a nice cage, lots of cooling work, 300whp sr, and tein's custom coilovers that were sent to them not sure what exactly. They did fairly well and well I thought the car kicked ass... so i'll see what their cage is like...

<a href="http://myspacetv.com/index.cfm?fuseaction=vids.individual&videoid=50704 24">Team Momentum GT - Redline Time Attack</a><br><embed src="http://lads.myspace.com/videos/vplayer.swf" flashvars="m=5070424&v=2&type=video" type="application/x-shockwave-flash" width="430" height="346"></embed>

[spool_sample]

Holy crap, that cage is a mess. If you went to any serious cage builder and told them you wanted that, they would tell you to go away.

Browse here: http://www.rollcageguy.com/

Local guy to me, looks even better in person from what I'm told.

No 240s there, but he did do the cage in this car: http://www.sportcompactcarweb.com/fe...0sx/index.html

[sr20goofus]

just so you know. Just because a car is fast or does good in a Redline HPDE (time attack), im bitter towards redline, does not mean it is setup well safety wise. Many cars dont have well designed cages. Everyone here is just trying to prevent you from spending money on something illegal or unsafe.

Great cage builder for east coast cars is...Piper Motorsports http://www.pipermotorsport.com/

[a_ahmed]

Essentially what I want to achieve is not have a cage just for safety (obvioous primary purpose) but to increase the chassis rigidity. I think what Koguchi concentrated was on chassis strength more so than safety or having a certified race legal cage... although in a different sort of way he has the points connect right above the head, im guessing in order to keep the impact above the user on the cage not on one's head. Different maybe stupid but :-/

[Wiisass]

So what are you trying to do? Design a cage? Or are you having someone build you a cage?

As for gussets not doing anything, some of them really don't do much, but a couple well places ones will really help out with overall chassis stiffness. The a-pillar gussets especially, really tie the chassis together with the cage, especially where the front of the cage is so open. B-pillar gussets do help a little as well. Unless the cage is touching the body of the car and welded to it, gussets will help. Some gussets are overkill and really not necessary. But gussets look sweet, so more are usually better. It's just a side benefit that they actually do stuff.

Here's a link to my gallery and some of the cages that I've done.

http://www.theoryinpracticeengineering.com/gallery/tipwork/

These are the more recent ones, but if you go up a level into the main gallery, there are more in there. The FC is one of my favorites.

But if you look at them, pretty much wherever more than 2 tubes meet forms a node. This will distribute the load better through the different tubes that are connected. The only place that I do not do this is at the upper door bar to main hoop joint. This if because most of these are drift cars and it's a sacrifice for more driver room over the best possible design. But if you look at the other points, everything comes together in the same spot. Most of them are pretty simple cages, just some extra gussets and an occasional extra bar in some places. Some of the extra bars will add some strength to the cage, but without doing more analysis, it's hard to say if they're adding more weight than they are strength. And really depends on what you're going to do with the car. If you're driving the car to events, you don't want bars going everywhere, you won't be able to fit anything in the car. But if it's a full track car, even then you don't really need bars going everywhere, especially if weight is an issue.

And then going a little off topic, that most people don't understand torsional rigidity and how much is needed or how it's going to effect everything. And additional X's and stuff just make the rear/mid part of the car stiffer, but then you have a huge gap between the front strut towers and the a-pillar bars. And if you break down the chassis into sections, it's like spring in series, and you still have a soft spring in there flexing all over the place.