Don't know too much about it but why don't many of the manuf. use A-arms in the rear of the car? Do any manuf. use them?

Manufacturer's that use rear A-arms,
1. Chenowth
2. Elite ( I bought one! )
3. Sidewinder, SV 16, 20.
I know there's more

I am no expert, but maybe because...

-With a trailing arm, the tire can take a hit from the front of the tire, and move back, and up out of the way of the obsticle (kinda like the front arms on a beam car) it seems like there would be less of sheering energy transfered to the arm mounts. I could be completely wrong on this though.


-With an A-arm, you have to have an upper and lower arm. This means 4 pivot points instead of two which could eliminate the above problem come to think of it . So bottom like.....I have know idea I guess

I can see the problem of needing 4 pivot points making it much more difficult.

I have found out that it's much easier to make a VW style trailing arm than to make a A-arm system for the rear suspension.
A-arm has similar components but most of them are NOT "off-the-shelf" like most of the current VW trailing arm style.

It's virtually possible to "mail order" all your parts for a trailing arm car and then have minimal fabrication to get things to fit correctly.

Most A-arm components are custom for a builders cars only. You CAN buy them and make them fit your car.


Carl

Rear A arms

Having owned both rear a-arm and trailing arm cars my opinion is that my rear a-arm car worked much better than my trailing arm car. I'm no expert, but i understand the following to be some of the techinical pro's and con's

1. A well designed rear a-arm car has no toe change and has camber gain. In a well designed trailing arm car you cannot have proper camber gain without toe change.

2. Rear a-arm cars have much less and in some cases no axel plunge as the heim joint piviot points at the chassis are in the same plane as the drive axel allowing much greater axel anglearity(sp)

3. On rear a-arm cars the roll center height can be controlled/adjusted. Trailing arm cars have no/minimal adjustability

4. Rear a-arm shock position creates congestion in typical radiator and gas tank mounting location

??? Aren't trailing arms, cheaper, stronger, and alot easier to set up on a rear engine car. I've never ran a-arms in the rear I've been completely happy
with my trailing arms, and most off road cars and pre-runners I've seen run
trailing arms or 4 link, I personally haven't seen a-arms on off road cars
wich leads me to believe a trailing arm is much stronger????

Not completely true.

Chenowth ran rear independent 5 link on the Chenowth Magnum for years. The short course Magnum was considered to be the car to beat in most cases. There were some Funcos and even a Nye Frank chassis that did very well. But by and large, it was a Magnum class.

And they also had a Desert car called the Arrow that had A-arms on it. It never made production levels. Their Genesis line is all A-arm I believe.

Stronger? Cheaper? Cheaper , yup I would guess that the mass of off-the-shelf parts would tend to make them cheaper.

Stronger? I'd say that it entirely depends on design. A-arm would tend to spread the load over a wider area of the chassis and not just on the "torsion housing."

I'd say that it is the easier of the two to set up and sell. And it looks beefy and to the uninformed, that speaks volumes.

And most racers have identical parts on their prerunner so they have a donor vehicle nearby in case a part is needed for the race car. Cannibals!

CArl

V8 Rail rear end:

Where's the motor???






























Sorry gents, if I didn't say it, someone else would have

It's a whole new ball game without a transaxle

yes , somebody had to say it

i like A-arms (its actualy a H- and I-arm on our cars) for the minimal axle plunge (+- 0.5"), low roll center (body lean) and lack of axle hop



the axles are also very well protected by the lower H-arm (we mount the aluminum skid plate/gravel guard as a upgrade )

not to disagree thats what I meant by ???? , but your going to tell me rear a-arms
are as strong as plated trailing arms like what I've seen on pre-runners????

Yes; how many TT, class 1, class 10, prerunners, dual sports and sand cars are out there that have front a-arms. A LOT. As long as they are built correctly they will last, just like boxed trailing arms. Same exact setup in the rear except your mounting points may differ, your rear wheels dont turn and you have a hub and some type of part driving the hub.

It looks like more people are trying it, so if you wanted a rear A-arm car you could get one.

Chenowth builds the Genesis as a play or pre-run car. If some one builds Genesis to race and it out runs the Millennium dogs then we might see more of them out there desert racing.

Nye Franks Ex-Riviera car never amounted to much. Possibly too many moving parts.

On page 29 of the April 2005 Dirt Sports Magazine, there is a picture of an all A-arm Class 10. Looks real fast! Didn't win...

This might just be the wave of the future, who knows? It just needs a bunch of money thrown at it until the code is cracked and then the world off-road will change.

I don't think trailing arms are as "off the shelf" as stated. The day that a Fodrill arm fits on a Funco, and a FrantzCo, and an Extreme then I will buy into the "off the shelf Cheapo theory. Until then I will assume that the trailing arm is the best method available at any cost. As an informed enthusiast, that knows the difference between 5 link and A-arms, I will defer to the engineers and experienced fabricators that build winning race cars today.

There is an opportunity for someone to build a measurably superior rear A-arm car. If that happens, then the industry will change. Until then it is just a theory for us to debate on the Internet.

Chenowth Exodus Rear Arms

My next car will have rear A-arms. I've done some research on it. My guess is it will be more expensive than a trailing arm setup. Depending on the design, it could use up to 16 heim joints in the rear (for both sides). Heims are not cheap.

I would say that yes, generally speaking, pound for pound, A-arms are stonger.

Most of the A-arms that I've seen have a better triangulation structure than trailing arms. It's the basic mount system as well. Let's say that they're both doing the same thing on similar cars. But the A-arm car is spreading the same weight over four or five locations versus the trailing arm with only two.

Just because most builders choose to use a certain method might mean that it's what sells and is generally accepted. Most of the time it's what is economically prudent. Not what might be the best performing.

** I didn't imply that "off-the-shelf" meant cheapo. You can buy a Foddrill arm from Kartek and McKenzies. You can buy a Jimco Spindle from McKenzies. Does that mean that it's cheap junk? No. It's called marketing.

And yes, those arms fit many chassis and applications. It's done for a reason. So the customer can buy a replacement if needed.

Carl

Single shear heims on the load bearing arm. Perfect play car.

Sadly enough, there ae many here that are forgetting the eveolution of this sport. It evolved around the VW chassis, engine and style of suspension. Was it the best? Probaly not. It was the cheapest. This is where the trailing arm got it's start.

And why did the racing community stick with the air cooled 60 hp VW for so long? Were there other alternatives? Yup.
Can anyone cite the reasons for moving directly to the Type IV instead of going with other imported lightweight engines of the time? Practically the whole off-road world is liquid cooled now.
They never wanted to move too far out of the box.

The off road racing community is often looked to for guidance on the "next hot ticket."

While most of them are looking elsewhere for the "next hot ticket."

It's a conundrum fer shure...


CArl

There is no reason to run 16 heims on a "true" a-arm style rear. You are not setting your car up with a rake in the rear so bushings would be fine. You could get away with running 4 heims in the rear for adjustment but only if it was built correctly and to your liking. On my car we are setting it up with bushings on the inner pivots and heims on the outer just for adjustability purposes. There is no reason to run 16 and it would be more of a pain in the a$$ to dial everything in. Depending on who you get them from will determine your deal. Id be willing to sell you 16 heims; no questions asked. I pay cost on the heims so that would be your price too.

I agree, and it probably will have inner bushings. I was just saying some cars might use 16 heims. Even with 8 heims it's more money than one big heim for a trailing arm. Thanks for the offer on the heims, but the rolling chassis will already come with them.

That is a cool statment. I'm sure that you have data some place to back it up.

My only data is last week in the Nevada 1000 there where 6 trailing arm cars in the top 10. The rest where trucks. A truck finished first. Maybe the future lies in truggies at the dunes?

You made the perfect example of the move out of the box. Nye Frank, backed by Riviera took the step and failed to yield results. That is a money and talent combo. You are a great guy Carl! Thanks for the exercise.

Who knows, some day over the horizon you might be right.

I think truggies will start becoming more popular when people finally get tired of dealing with transaxles.

If truggies are going to become the thing to have then the motor will be in the front. Isn't there someone already doing that?

i dont realy see the relation betwene Nev1000 style desert racing and duning
i grew up with "Rally Raid" Racing: IMHO one of the only motorsport where the cars actualy have to handle, turn and perform very well in the dunes and the desert.



not many trailing arms and rear engines there



thats where i look for inspiration : other opinions may vary

Hmmm, what about this Jimco/VW Dakar race car?

where they ended last winter

lost again against Mitsubishi big time , and was barely ahaed of Nissan





looks like the Mitsu is a better concept


BTW I still remember the twin engine DAF semis and the 1000HP Detroit boat diesel powered Perlini 's running circles around Schlesser in his SoCal build desert racer... that was hilarious, but many many years ago when they let the semis really fly.

...as i posted; opinions may vary
IMHO i stick with A-arms as long as they work perfect for our car and our driving style

btw notice in the 2nd pic the lack of "ackerman" angle in the front end geometry

They hold up just fine on the front of cars, cant see why it would be an issue out back. My guess is that they are more expensive to build and harder to setup.

Two different classes of race vehicles.

BTW, why don't you V8Rail guys build Rally Raid cars? Since you can do it better than Jimco, you probably get a lot of phone calls from the race teams, right?

Awww...


typical King reaction as soon as somebody has a different opinion
as i posted: i look there for inspiration
i m not a "wannabe" racer ; i just like to go fast into /around turns....IMHO A-arms work better there= thats what we use

I think Chenowth offers the rear a-arms or trailing arms for the same price on their new exodus cars. Looks like they have updated their site.

http://www.chenowth.com

There are two answers to this :

No, both factory supported race machines running the same race in the same class.Mitsu had smaller engine with less HP....
but yes you are correct it looks like the A-arm setup is a class above


Nowhere I said that. Each time you are not right you try to bring the quality of discussion a couple steps down ....

but anyway I give you a answer to that silly post :
We would not have the money and resources to compete there.

... But VW spend the money and resources and lost again ... so maybe the concept is wrong ...

I'm just messing with you guys. Actually I don't have a different opinion. I think rear A-arms are a great idea.

But to say they are "better" than trailing arms is a matter of opinion.

Buggyshop a-arms.
These cars work great. Suspension designed and modeled after RC cars.

http://eaglefab.net/ another place to check out a-arm rear ends.. I just love thier cars..

But if you continue to make the same old product and don't step out of the box, we'd still be using the 1600 VW for everything!

Glad someone at least added water!

The Nye Frank comment fails to include his dominating Jerry Whelchel Mickey Thompson short course car. I know that there were other really good ideas too, but can't think of them for now.

Sounds like you miss the 1600!

Carl

everyone seems to agree trailing arms are cheaper and easier to setup,I still only
read opinion that REAR a-arms are as strong as plated trailing arms. Or am I answering my own question?????

Why wouldnt they be as strong?

Mike's cars are 5-link rear suspension, unless he changed the design.

Late, PATCO

its how the arms are constructed and mounted,as well as personal opinion that will decide YOUR OWN thought between the two

I'm convinced by this topic that at the dunes, you should run what makes you happy. If you can afford it, build it, or have it built... The parts are as strong as you build 'em. Some times they end up too heavy but it will get you rolling.

I'm new to this forum. I learned a lot here. Like, there are people putting V8's in the front with A-arms in the rear. And thet are driving them and people are buying them.

Sounds like you miss the 1600!



This forum would have the world beliving that the minimum engine for the dunes is a Subi and most guys have V8's. If you ever go to the dunes you will see as many VW's as anything else except quads of course.

At the Laughlin Desert Challenge there where 78 Type 1 engines this year.

Are you from around here? From the looks of your fish and your signature I would guess you where from down under. Not that there is any thing wrong with it...

crazy, isnt it


...and the A-arm rear works perfect on the street too

OK, I don't have a trailing arm or A-arm rear end. My car has the five-link variety. Where do these come into the mix?

My observations are the trailing arm setups are in either older vw-torsion types or heavier four seater rear engine cars. Five-link setups appear to be the rear of choice on a lot of mid engine cars. The less seen A-arm rear setups are mixed between mid-engine two seaters and rear engine four seaters.

That is bad ass! I'm sold!