Swing vs. IRS

wiley2006 · Post by **wiley2006** » Mon Apr 04, 2005 3:18 pm

Is converting a swing axle car to a IRS car worth it in terms of handling vs. time/money?

Expert opinions wanted

Post by **Marc** » Mon Apr 04, 2005 3:55 pm

For basic transportation, probably not. For use on unimproved roads swingaxle is arguably the better choice. For spirited driving or if an emergency maneuver is needed at high speed, there's no doubt that IRS is head & shoulders above swing.
But don't whack up a restorable `67, please!

rsrnate · Post by **rsrnate** » Mon Apr 04, 2005 6:55 pm

I agree with Marc that for a daily driver or play car swingaxle is fine, but for circuit racing or auto-x a swingaxle will never handle like an irs car

gcorrado · Post by **gcorrado** » Tue Apr 05, 2005 2:18 am

one other thing to add...

in the hands of a less than stellar driver, i swing axle can be a problem in emergency maneuvers even on the street.

yeahmag · Post by **yeahmag** » Tue Apr 05, 2005 10:19 am

Now... All that being said, a swing axle car can be drive fast and hard. I race my '66 swing axle in autoX car from time to time and have a blast. I've been told the new White Line bars for a swing axle are magic!

-Aaron

yeahmag · Post by **yeahmag** » Tue Apr 05, 2005 10:20 am

For example, uncorrected time I was only a few seconds behind a late model BMW 2002 in this last Solo2. And I have amazingly bad tires!

-Aaron

Post by **Marc** » Tue Apr 05, 2005 10:30 am

Yeah, I used to campaign a swingaxle circletrack car too and it's true that they can be made to handle for a specialized application, but the result isn't anything that's the least bit pleasant to live with on the street. There's no getting past the fact that you've got a high rear roll center (and nothing can change that, it's designed into the suspension) and a track width & contact patch that change radically with suspension travel. A slammed swingaxle with limited suspension travel can use a rear swaybar but they're a fatal mistake for a street machine.

Jerry D · Post by **Jerry D** » Tue Apr 05, 2005 3:36 pm

I have been doing pretty well in the local Autocrosses in my swing axle Manx. I'm running limiter straps, adjustable spring plates, a camber compensator , and 13" wheels and tires. With the rear being low and stiff and the engine having about 200hp I can just drive it thru the turns with the throttle. I do think I would be better at drifting it though.
I switch the tires and jack the suspension back up for street use.

Jerry..

Post by **Marc** » Tue Apr 05, 2005 3:49 pm

Jerry, the camber compensator is redundant with the limiting straps but it's a lifesaver when they aren't on (or if one should break). Still, it's quite possible to flip that car if the outside wheel hooks up unexpectedly in mid-slide. Drifting it would require a death wish IMO - be sure you have a good cage (solidly-mounted, not something that'll poke through the floorboards if you end up on your head), harness, and arm restraints if you do so...please.

Jerry D · Post by **Jerry D** » Tue Apr 05, 2005 7:52 pm

I leave the compensator on just to take some of the shock off the limiting straps. The buggy does drift very well as long as I have the limiting straps cinched down tight. When they are cinched down the camber cannot go positive.

Jerry...

wiley2006 · Post by **wiley2006** » Wed Apr 06, 2005 5:39 pm

A car that has been converted to IRS can be just as easily converted back right? I could keep the swing floor pan

Jerry D · Post by **Jerry D** » Wed Apr 06, 2005 5:49 pm

You can remove the trailing arms and put the swing axle springplates back on and have a swing axle car but the pivots for the trailing arms will still be on the pan.
Jerry...

69bajakid · Post by **69bajakid** » Sat Apr 09, 2005 2:34 pm

I hear allot of smack talk about swing axle cars and rear sway bars and death machine on the street..i say B-S

I have driven the piss out of my swing axle car (was long axle) to the point where i have turned my axles and tranny into mush..bult a new tranny..with some SAW short axles..drove the piss out of it..loved it..installed a bugpack rear sway bar..some Gas a just shocks..urethane spring plate bushings..bus snubs...and adjustable spring plates..and it is FAR from a death machine..all parts were added with test drives inbetween..the swaybar was first on the car..it rocks..hands down..the main span of the bar mounts to the underside of the frame horns..then there are pair of long pins that link the bar to the bottom shock bolts

i dunno why so many ppl say that rear bars are bad news..i will take ya for a rip in my car then you can choose

(i also run a airspeed.com 3" narrowed BJ style sway bar up front)

Cale

rsrnate · Post by **rsrnate** » Sat Apr 09, 2005 4:13 pm

I am not talking smack about swing axle cars as I used to race my 63 sunroof till it got stolen

I love early cars way better than 68 and up but now that I have built both a link pin ,swing axle car and a balljoint,irs car I can tell you first hand that an irs car will run circles around a swingaxle car. You can make a great handling swingaxle car but the irs will always handle better.

69bajakid · Post by **69bajakid** » Sun Apr 10, 2005 8:43 am

Ohh yes i 100% agree with you..i was just trying to say that a hi-po sway bared swing axle machine does not have to = trouble

my next car will be IRS for sure.

Cale