Why IRS ?

The rear suspension often referred to as 'IRS' is, IMHO, trailing- arm.

Surely swing-axle and trailing-arm are both independent rear suspension (IRS).🤪 Hope it doesn't sound pedantic, but non-VW people - yes, there are some - have trouble understanding.

Cheers, Greg

P.S. Guess which IRS I prefer? 😂

yes true
i think the best way to call it is swing axle and live axle

either way its good as long as yr driving a VW

Yea they are both forms of independant suspension, and ur right, the nick named 'irs' is rear trailing arm suspension :P

Choosing which suspension setup to go with for ur new dub racer i guess hey :P? Keep us posted!

I guess ur a swinger 😂??

One day I may explain why swing- axle is better than trailing arm - but non on here.🙄 (My typing is super-slow, and I STILL can't up-load pics🤪)

Ever driven a 914 (rear trailing arms)? If so, you will understand😉

Hey Greg.

I'd love for that day to be today. Hit me an email with pictures and i can host them for you, not a problem.

Yes, I honestly would like to know what you think. Why? Because Apart from strength, I see very little reasoning for how it is better. But you know, I am young and 'apparently' don't know very much.

No, I've never driven a 914, but it have drive late model "swing axel" and, "IRS" Beetles, and know which I would chose any day of the week. I also own that car.

So, lets hear it.

To all - Don't get all "gosh Colonel mustard" on me, Greg started the thread, and clearly has an opinion, so lets hear it 🙂

Cheers.

I agree with colonel, id love to hear what you have to say greg, and i like to be able to go back to it and refer others to it. Send your pics to colonel so he can get em up

Josh, give me a call, and pop around. I can explain all - and do a few sketches, then you can stick it on the bloody 'puter😏, for all to see ( and probably shoot me down)🥲 0402 415 022

HappyDaze wrote:One day I may explain why swing- axle is better than trailing arm - but non on here.🙄 (My typing is super-slow, and I STILL can't up-load pics🤪)

Ever driven a 914 (rear trailing arms)? If so, you will understand😉

what?dont say that greg im almost finished my irs conversion.... why do all the circuit guys woffle on about trailing arm bug??

and colonel , gregs ideas work,i did them to my swinger and they made a big difference..way better then those camber compensators you buy off the shelf.. hope you have 8 drill bits to drill through spring steel though..lol....

colonel mustard wrote:Because Apart from strength, I see very little reasoning for how it is better.

Less unsprung weight. And also less bits there so there's less components to wear, fail or go wrong.

But I would also love to hear any other reasons, I don't think the reasons I've mentioned above outweigh the pros for "IRS" though. Especially on an offroad car. Because the spastic camber can be downright dangerous on a swing axle at speed.


Smiley 😎

You are right, Smiley. Any 'big' travel - off road etc. - is not good for swing-axle suspension. My involvement has been with circuit racing.

how many modern cars have swing axle rear suspension I am sure its cheaper to build so where are they❓

RISKY4LIFE wrote:yes true
i think the best way to call it is swing axle and live axle

Not so! The best way to describe it is swing axle and double joint axle with trailing arm suspension, both designs being IRS! A live axle is nothing like our VW rear end but plenty to do with older Holdens, Fords,etc etc!

See: http://www.google.com.au/images?hl=en&q=live+axle&um=1&ie=UTF-8&source=univ&ei=JZ49TPKoIIvKvQOP64jtDg&sa=X&oi=image_result_group&ct=title&resnum=4&ved=0CDcQsAQwAw

DH

there are none, why coz its ridiculously dangerous. Now I have nothing but semi tailing IRS coz of my love for late type 3s. But I did restore a sprint car looking bugy based of an early t3
with swing axle. God! that thing handled like a piece of crap. Even driving in a line its started to sway side to side. Mainly due to the fact that the massive rear wing would cause enough
down force to push the rear down so that is caused excessive camber and toe in would cause the rear to ramp up, down and sway side to side.

swing axle 👎

ridiculously dangerous? I dont think so. Would hazard a guess that it was more the set up of a sprint car looking buggy and stupid wing that was more dangerous. If you can drive a swinger at max speed and take your hand off the wheel then I cant se how it is ridiculously dangerous.

Throwing one through a corner without limiting the travel could be another matter

A few years ago I limited the travel on a HR stock car (inside rear wheel) and all that happened was that I ended up on the roof!

So hows it go on a swing axel?

Newt

yes i drive my cars hard around corners. Also even with the wing removed it still handled crap but some what better.
My neighbor had a go once and he stacked into a massive prickly bush first turn coz of snap over-steer. Then after that I worked out I could put limiting cables, which improved it again some more.
But in the end it still sucked. The irs in my old square actually handled better than my vp commodore when they both had 185 tyres. After a while I got 205 for the vp and being 25 year newer tyres than the type 3 had. and it was better
but still slid around corners like commodores do.

The commy has live axle. so it tends to handle like a bigger heavier go cart kind of characteristics.

Newt wrote:A few years ago I limited the travel on a HR stock car (inside rear wheel) and all that happened was that I ended up on the roof!

So hows it go on a swing axel?

Newt

you'd want to limit the travel on the outside wheel so that it doesnt tuck under.



I'm not really sure how the human population survived the 50's and 60's when one of the most popular forms of transport was ridiculously dangerous.

But I'm kinda getting the drift now that I know your neighbour stacked your buggy and the double joint type 3 could out handle a VP commodore. I also recall stacking my Datto 180B big time and I think it was kinda swing axelly. I also cheated death by spinning my mac strut all round telstar on a road that I swear was narrower than the length of the car, but didnt cause a scratch. Conversely in all the years I raced my double joint kombi I only ever had 1 small accident.

EDIT: and I've seen greg and wayne crash their respective swing axle race cars.

im gonna go back to calling them IRS now, not double jointed, we all know what we're talking about.

PAZZAN wrote:how many modern cars have swing axle rear suspension I am sure its cheaper to build so where are they❓

Porsche 914/916 Porsche 944 Porsche 912

all had the rear IRS trailing arm rear suspension... as VW had..

some even aluminium...

LEE

Have a look at this video, it was shot in 1970, so all those VW's would have been swingaxle!

http://www.youtube.com/watch?v=YZb7sbRFCF0

yes I seen that. That exactly how it is with swing axle.

watched mr mackie at wakefield, no TUCKEN probs there!!!!!

Hee hee, luvd the second car, the red one, must have been on his way to school, all his homework spilling out onto the track, and the soft top with four on board, or was it five, couldn't focus I was laughing so much. 😀

There are much better suspension designs than either (swing-axle or trailing arm), that is why I went for double wishbones on the back end of my 550 Spyder.👍

My belief is that the swing-axle rear end CAN be set up in such a way as to use some of it's design to your advantage. Don't just 'give up'.

Body roll, for example, will DECREASE camber of the outside rear wheel of a swing-axle car, whereas it will INCREASE in the case of a trailing-arm car. That's why you see monstrous ant-roll bars on rear trailing-arm cars,

There are MANY things that can be done to improve the swing-axle rear end, such as lowering the effective roll-centre (with the help of a strong compensating spring and 'softer' torsion bars), limiting 'droop', and so on. My 'typing finger' is saying STOP now.😂

Cheers, Greg

Is this the ultimate swing-axle race car?

The Type C Auto Union race car of 1936-37, designed by Ferdinand Porsche and developed further by his son Ferry. Powered by a mid-rear 6-litre supercharged V16 developing 390 kW (520hp) and over 850 Nm. 340 km/h top speed. Torsions bars front and rear, drum brakes.

Berndt Rosemeyer won the 1936 world championship in it.

Im ging to see greg on saturday and im sure he will give me some good info and pics which i will post here if he wants.

Phil74Camper wrote:Is this the ultimate swing-axle race car?

The Type C Auto Union race car of 1936-37, designed by Ferdinand Porsche and developed further by his son Ferry. Powered by a mid-rear 6-litre supercharged V16 developing 390 kW (520hp) and over 850 Nm. 340 km/h top speed. Torsions bars front and rear, drum brakes.

Berndt Rosemeyer won the 1936 world championship in it.

Rosemeyer mastered the swing-axle Type C😎 Nuvolari wouldn't drive it - said it was dangerous, although he drove the Type D, which used a De Dion rear suspension. Dr Porsche did not approve.❗

Swingaxle has some unique design advantages in certain situations I'm led to believe, whether these outweigh the disadvantages probably depends very much on the driver and situation. I have a preference for IRS mainly because Im lazy and Its easier to take the gearbox out!!

Yes Greg the Type D lost the swing axles - plus it only had a 3-litre V12 (with 480 hp). That one was designed by Eberan von Eberhorst, who also designed the Tiger Tank and assisted with the V2 rocket and the post-war Porsche 356. Rosemeyer must have been some driver. He lost his life doing what he loved. His souped-up Auto Union Streamliner flipped at over 430 km/h during a speed record attempt on the Autobahn in 1938.

For the VW, swing axles were inexpensive to build; strong, reliable and gave a better ride than other mass market rear suspension designs of the 1950s. For the driving situations that VW made their cars for, swing axles were perfectly adequate at the time. VW never built them to be performance cars.

But look at what 'big brother' Porsche did. The 356 also used swing axles, with considerably more power than the VW ever had. Even the exquisite 2-litre 130-hp four-cam 356 Carrera 2 used swing axles, but with an additional transverse leaf spring (a factory camber compensator!). It was only when the 911 came along that Porsche went to double-joint rear axles and CVs.

Phil, Rosemeyer was, in my opinion, one of the best! The story goes that he was a motorbike rider, and he asked for a drive of the Auto Union at a test day. He went out and lapped quicker than anyone had ever done before. 👍 The rest is history. He met his end on the speed record attempt, as you said, when hit by a cross wind.

Cross winds and swing-axles are not good friends. At Bathurst in 1962, my Beetle was motoring happily down Con-Rod Straight (no Caltex Chase then, staight all the way)at 102 MPH (165 KPH) when suddenly at the exit of the cutting the cross wind hit! The car hopped sideways about a metre and woke me up immediately. Rocking the body like that causes rear wheel steer, as one rear wheel 'toes out' as the other 'toes in'. A bit scary when you're not expecting it, but it never caught me again - next time I was ready for it.😂

Cheers, Greg

i for one would love to hear and see youre theories greg as im a swinger link pin terrorist too!

You coming up to valla?

another brave man Damien,🙅: swing axle is ok when u known what your doing not for beginners..👍

oh dear im in trouble then!

that said, you'll never know what your doing if you never start... so we should all drive swingers and go hard! 😁

sander288 wrote:that said, you'll never know what your doing if you never start... so we should all drive swingers and go hard! 😁

Gotta be a few lines in there somewhere but I think I'll just move right on along. 😘

When I built my bug(1990),the advantage of an IRS chasis over a swing axle was that the later gear box was stronger.Is this still the case,or can you now build a strong swing arm box.
I blew 2 early boxes when I had swing axle.(1640cc P plater)The IRS chasis and later box seemed to be much tougher.
I also found that with the IRS chasis,from a 69 semi auto, my 66 delux handled alot better.
Im no expert but if you go swing axle,run a camber/caster bar like they do in formula vee.It will minimise rear wheel tuck,prone to swing axle suspensions.

HappyDaze wrote:The rear suspension often referred to as 'IRS' is, IMHO, trailing- arm.

Surely swing-axle and trailing-arm are both independent rear suspension (IRS).🤪 Hope it doesn't sound pedantic, but non-VW people - yes, there are some - have trouble understanding.

Cheers, Greg

P.S. Guess which IRS I prefer? 😂

Naturally they are both Independant rear suspension...
not a live axle which was in one piece...
either wheel can go up or down....

but swing axles YIKES...

the wheels go in and out.... while you are driving...

massive camber changes... can't be good at speed..

and I've never rolled a CV joint IRS.... lol
because the wheels don't go in and out....

so, I'm a converted IRS person... VW driver...

LEE


THE BEETLE HANDBOOK [ENGLISH TRANSLATION]

ok u swingaxle guys lets see u blokes enter a supersprint at easterncreek,love to see a swinger going through turn 1 at 180 kph plus😂
😂

I'd have a go, but my car won't do 180kph.👎 It does (or did)😢 the kink at Wakefield at 160kph, though.👍

Cheers, Greg

been in a spin at turn 1 at 190kph in my old bug went around 4 times in the middle of 25 other racers lots of smoke of the tyres but never felt lke it was going to roll...wakefield kink is a non event sorry🙅

Turn one at Eastern Creek IS great - been round there at over 200kph in the 'VW Fairmont' (GT-3 Porsche). 🙄That's got a proper rear end though (double wishbones)😂

Cheers, Greg

gt3 thats cheating👍