rear sway bar recommendations

[Jim Lusk]

Like chicken wire and bodywork, the two things are just not related.

I seem to recall seeing that on some car at some point in time...

 

[Woody500]

And right here is the problem^^^^, it's not a simple question, and intended usage has a 50% affect this decision....the important thing is the total package.
Per the OP He's only got the stock front 3/4" bar from a '73 & up, that's not enough to use a rear bar w/the ESPO's. The frt .870" T-bars are a bit soft, but here, the usage DOES matter. Rural roads, especially like Mine, have a lot of rapid elevation changes.....straight on or mid-turn, like a ralley, so more stored energy does a better job keeping the tires in contact with the road when the suspension moves into rebound.
Basically, the OP needs a bigger frt. bar, before considering a rear one. And the best shocks He can get.

Great explanation of your point. Thanks. I've no experience w/Dusters, and always thought they looked light in the rear, which was comfirmed in an earlier post. They look great lowered for handling, too.

 

[RustyRatRod]

Nice!

I started AutoX in a different make/model as well. 16 year old me giving the beans to my '56 Austin Healey 100 at my first autoX.
View attachment 1716472493



Whaaaaat?!

You can't just slap them in and expect everything to work the same as it did with a rubber bushing? You have to upgrade the whole system? Blasphemy!

Very cool stuff! Thanks for sharing. My very first car was a 67 Triumph Spitfire. It was a cool little car, also British Racing Green. The girls loved it. lol Our high school shop class instructor had an Austin Healey Sprite bug eye, also British Racing Green. lol

 

[Woody500]

That Austin looks like a blast to drive !
I sold high end cars for 25 years …. BMW , Porsche, Mercedes,Jag , Acura and Audi.
( 2 different dealers ) and the manufacturers would put on “Ride and drives”…. They would have their newest models and the competition there to drive . Some events were in parking lots others on tracks . Ripping around a track in 911 Turbos , BMW M-Series , AMG Mercedes and Acura NSX’s was pretty cool ! They would always have professional drivers at these events . One time in Pheonix AZ I had een driving all morning with a pro and when we broke for lunch he shook my hand and said “see you after lunch” … I looked at his name badge and realized I had been driving around a track with Roberto Guerrero ! It took me a second to process his name and by that time he had walked away . At lunch I went over to apologize for not paying attention to who he was . He said no problem… BTW this is Davey Jones” !

Man those guys can cut a lap time SO much faster than the average guy and look slow doing it !
I also spent a week at the old AMC proving grounds in Wisconsin with Audi . The Germans know how to put on an event ! No expense spared .

Acura sent me to the Honda proving grounds in Ohio to drive NSX twin turbos and 911 Turbos for 3 days . It paid off for Acura as I sold 5 NSX’s at $230k a pop . Not bad for a little dealer in Boise Id .

Anyways I just thought you autocrossers would get a kick out of those stories .

I was in Atlanta in 1983, working on the movie Tank at the old Lakewood Fairgrounds & Audi was having an event there & somehow got to ride around the old Lakewood Park Speedway, with a salesman? I'd say the car must've been a Quattro(IIRC)as it was a dirt track. And his driving didn't impress me with the concrete walls, and the tracks' reputation. And track not prepared. Rough & rutty.

 

[72bluNblu]

There is absolutely nothing wrong with lifting a tire in autocross, especially FWD. Sometimes you want the car to rotate, not stick. Some bad assumptions in your thinking.

I have been autocrossing on and off for 40 years in FWD, AWD and RWD cars, front and rear engined. I am decent at it, not great by any means. I do have one SCCA regional championship. I have no idea who Randy Pobst is without googling him. Rotating the car for the purposes of this discussion is in reference to a FWD car, you charge into the corner, lift off the throttle and turn, weight shifts forward, the car lifts the inside rear tire and the rear of the car slides sideways (car rotates), when the car is aimed where you want it, you get back on the throttle, weight shifts rearward, the rear stops sliding, and you accelerate out of the corner.
Have you never seen the pictures of the Lotus Cortinas going round corners a three wheels (driven by some of the greatest drivers ever)? Have you never been to the Daytona 24 hours and seen the Porsches going round the infield turns on three wheels?

Also Physics still apply, no matter what class. & all info about all classes is info that's worth knowing. You never know where the next idea will come from.

Both of you have missed the point entirely. Yes, I've seen lots of cars lift a wheel. Different makes/models of car, different drive layout, different competitions and racing classes.

BUT, just because you see certain cars in certain classes lifting an inside wheel does NOT mean that lifting a wheel is good or that it's necessarily the fastest way around the corner. In some cases and some corners it might be, that's true. But in most cases it would be better to have that wheel on the ground-if it's possible on that chassis with that suspension in that particular corner.

The issue is that it's not always POSSIBLE with the chassis, suspension and class rules to make the modifications necessary to do that. Picking up the wheel means you've exceeded the limit of the chassis and the suspension to keep the wheel on the ground. And on some chassis and suspension layouts it may be unavoidable. Is it inherently bad? No, but it's also not a desirable effect.

Suspension design and set up is ALWAYS a trade off. Especially in racing, you may end up with really stiff wheel rates and fairly short suspension travel to deal with really high suspension loads from high speeds and soft tires. That works most of the time, but in some situations it also may mean picking up an inside wheel because your roll angle has exceeded your suspension travel. Now, you could set up the suspension with longer travel, or modify the chassis, or run more spring and roll rate etc so as to keep that from happening, but then the overall handling of the car might suffer the rest of the time. Trade off. Like picking lines in some corners in pretty much any racing event, the "best line" through a single corner might not actually be the fastest way to get around the track on the whole. Compromises are made, you go slower through a single corner to set up the next that has a larger lap time impact, or get better traction to put down more power coming out of the corner, whatever.

Bottom line is just because it can happen doesn't mean it's good. And it certainly doesn't mean it's relevant for picking a rear sway bar on a very basic street going A-body!

Great explanation of your point. Thanks. I've no experience w/Dusters, and always thought they looked light in the rear, which was comfirmed in an earlier post. They look great lowered for handling, too.

Duster's aren't substantially lighter in the rear than any other A-body. In fairly stock trim most A-bodies are in the 57/43 % for front/rear balance. It can be improved substantially, and weight reducing efforts have a much larger impact than body style.

There's a bunch of different results posted in this thread, most of the somewhat street going cars are near 55/45
Stock weight distribution for various body styles - can you improve balance w/out drastic mods?

The results vary a lot by set up, but the best balanced 67+ car in the thread is a '71 Duster at 52/48.

 

[mbaird]

I was in Atlanta in 1983, working on the movie Tank at the old Lakewood Fairgrounds & Audi was having an event there & somehow got to ride around the old Lakewood Park Speedway, with a salesman? I'd say the car must've been a Quattro(IIRC)as it was a dirt track. And his driving didn't impress me with the concrete walls, and the tracks' reputation. And track not prepared. Rough & rutty.

Not sure if it was the case then but if you wreck a car in one of those events your dealership buys it … lol. I know a few dealers bought some $200k+ cars .

 

[mbaird]

Both of you have missed the point entirely. Yes, I've seen lots of cars lift a wheel. Different makes/models of car, different drive layout, different competitions and racing classes.

BUT, just because you see certain cars in certain classes lifting an inside wheel does NOT mean that lifting a wheel is good or that it's necessarily the fastest way around the corner. In some cases and some corners it might be, that's true. But in most cases it would be better to have that wheel on the ground-if it's possible on that chassis with that suspension in that particular corner.

The issue is that it's not always POSSIBLE with the chassis, suspension and class rules to make the modifications necessary to do that. Picking up the wheel means you've exceeded the limit of the chassis and the suspension to keep the wheel on the ground. And on some chassis and suspension layouts it may be unavoidable. Is it inherently bad? No, but it's also not a desirable effect.

Suspension design and set up is ALWAYS a trade off. Especially in racing, you may end up with really stiff wheel rates and fairly short suspension travel to deal with really high suspension loads from high speeds and soft tires. That works most of the time, but in some situations it also may mean picking up an inside wheel because your roll angle has exceeded your suspension travel. Now, you could set up the suspension with longer travel, or modify the chassis, or run more spring and roll rate etc so as to keep that from happening, but then the overall handling of the car might suffer the rest of the time. Trade off. Like picking lines in some corners in pretty much any racing event, the "best line" through a single corner might not actually be the fastest way to get around the track on the whole. Compromises are made, you go slower through a single corner to set up the next that has a larger lap time impact, or get better traction to put down more power coming out of the corner, whatever.

Bottom line is just because it can happen doesn't mean it's good. And it certainly doesn't mean it's relevant for picking a rear sway bar on a very basic street going A-body!



Duster's aren't substantially lighter in the rear than any other A-body. In fairly stock trim most A-bodies are in the 57/43 % for front/rear balance. It can be improved substantially, and weight reducing efforts have a much larger impact than body style.

There's a bunch of different results posted in this thread, most of the somewhat street going cars are near 55/45
Stock weight distribution for various body styles - can you improve balance w/out drastic mods?

The results vary a lot by set up, but the best balanced 67+ car in the thread is a '71 Duster at 52/48.

Smooth is the winner . Again… the top pros I have been with don’t look or feel like they are going that much faster but they never scrub speed . It’s an art !

 

[mbaird]

The OP just wants a nice handling street car . Properly matched front and rear sway bars will accomplish that.

 

[abodyjoe]

The OP just wants a nice handling street car . Properly matched front and rear sway bars will accomplish that.

may not even need a rear bar,, our dart drives and turns great with only a front bar, i think i have heavier rear springs though.. personally i'd drive it and see what it needs fromt here.

 

[mbaird]

may not even need a rear bar,, our dart drives and turns great with only a front bar, i think i have heavier rear springs though.. personally i'd drive it and see what it needs fromt here.

If you drive halfway sane that is true . We drove these cars in stock form for decades and thought they were fine . I didn’t use a rear sway until around 2015ish . But man it really made the car hold the road . I currently run 205/70-14s because I like the stock understated look and it still holds the road . But with the addition of a 4” crank and 46rh it’s painfully evident I will need more rubber under her . 1/4 throttle stab roasts those poor little Michelins . Looking at ordering some Hankook 235/60-15s .

 

[abodyjoe]

If you drive halfway sane that is true . We drove these cars in stock form for decades and thought they were fine . I didn’t use a rear sway until around 2015ish . But man it really made the car hold the road . I currently run 205/70-14s because I like the stock understated look and it still holds the road . But with the addition of a 4” crank and 46rh it’s painfully evident I will need more rubber under her . 1/4 throttle stab roasts those poor little Michelins . Looking at ordering some Hankook 235/60-15s .

we run a 225/60-15 all the way around.. holds the road great.. just got back from a trip that took us on the tail of the dragon.. car felt great on it even though i couldn't go all that fast because of traffic.. not sure how fast i could have taken that road anyway.. the car does feel much like a modern car.. slide all over with the bench seat though so that kinda sucks..

 

[72dustervs]

And right here is the problem^^^^, it's not a simple question, and intended usage has a 50% affect this decision....the important thing is the total package.
Per the OP He's only got the stock front 3/4" bar from a '73 & up, that's not enough to use a rear bar w/the ESPO's. The frt .870" T-bars are a bit soft, but here, the usage DOES matter. Rural roads, especially like Mine, have a lot of rapid elevation changes.....straight on or mid-turn, like a ralley, so more stored energy does a better job keeping the tires in contact with the road when the suspension moves into rebound.
Basically, the OP needs a bigger frt. bar, before considering a rear one. And the best shocks He can get.

Yea I plan on ordering the front Hellwig as well , if the rear comes in Feb then I will worry about front at that time , and afterwards when I think about the torsion bar replacement some more , no hurry since I just ordered a 18 spline tranny from Brewers as well , I have an OD 833 in it now but but its untested , and if the OD tranny has any issues then I can quickly swap and may swap anyways as I like the 18 spline which of course will be a little more weight

Which set of ESPOs did You purchase, 6-leaf? Stk ride height?

I thought I had ordered the 6-leaf because I put in a new 8 3/4 rear , but after double checking its not , so stock

 

[mbaird]

we run a 225/60-15 all the way around.. holds the road great.. just got back from a trip that took us on the tail of the dragon.. car felt great on it even though i couldn't go all that fast because of traffic.. not sure how fast i could have taken that road anyway.. the car does feel much like a modern car.. slide all over with the bench seat though so that kinda sucks..

I try not to drive recklessly (anymore) but do like a car that goes where I point it and I live in the mountains so I encounter lots of sharp turns with fast moving rivers beside me or 1000’ drops .

 

[mbaird]

Yea I plan on ordering the front Hellwig as well , if the rear comes in Feb then I will worry about front at that time , and afterwards when I think about the torsion bar replacement some more , no hurry since I just ordered a 18 spline tranny from Brewers as well , I have an OD 833 in it now but but its untested , and if the OD tranny has any issues then I can quickly swap and may swap anyways as I like the 18 spline which of course will be a little more weight



I thought I had ordered the 6-leaf because I put in a new 8 3/4 rear , but after double checking its not , so stock

I don’t recall your engine build but if it’s a mild build with under 400 hp the OD will work great . I ran one in a 73 340 4sp Dart Sport and drove it from Boise to BIR raceway in MN …ran high 12s and drove home . People couldn’t believe I drove all that way with it . Springs shouls be fine … I have the Mancini XHD springs on my Barracuda and it took a while for them to settle in . The 69 Dart with W2s , solid roller and a 4 sp has SS springs .

 

[abodyjoe]

I thought I had ordered the 6-leaf because I put in a new 8 3/4 rear , but after double checking its not , so stock

espo 5 leaf ? they were pretty weak when we had them years ago..

 

[72dustervs]

espo 5 leaf ? they were pretty weak when we had them years ago..

They will do for now , got to many other things to do lol , if I end up thinking they are weak I will cross that bridge then , for now waiting on Bilstein shocks and rear sway , and may end up changing the tranny to the 18 spline I just bought , and sell my OD or buy a another project , I got a 440 block waiting for something