Apex Engineered Track Attack - anyone actually running it yet?

[zbloke]

I appreciate that the following isn't the Apex Track Attack system but a fellow Hybridz member built, installed and ran a pushrod/rocker/inboard damper rear suspension on his car some time ago, I don't know if he is still active on here but a search of his past posts might give you some insight into how he fared with his system

 

https://forums.hybridz.org/topic/91914-rocker-arm-rear-suspension/

 

[Coelocanth81]

Thanks for posting this - I could've sworn that there had been an attempt at a pushrod linkage suspension before...

[///M3 & Z]

I started thinking about the Heim joints after you mentioned it. There are a lot of them, 22 In the rear kit to be exact. If you planned on replacing those with the ridetech R joints it would cost you $1900 usd to buy enough of them. 

People seem to say they get contaminated pretty fast with dirt and road debris, would hate to have to be either cleaning or replacing that many of them.

Iv always also wondered what the cabin noise would be like with the struts and joints being right behind you inside. I like loud engine and exhaust sound but little bumps and vibrations I'm not a fan of at all.

 

 

[Ironhead]

It's funny...I have heard a wide range of opinions about Heim jointed cars.  Some say they wear and start "clicking" almost immediately, others say they get thousands of trouble free miles out of them.  I guess I'm about to find out, as my project car has a crap load of them.

 

I am interested in the R joints in concept, but I don't understand what makes them superior to standard Heim joints, other than costing 3X as much.  They do not appear to be "sealed" from dirt and moisture, and while the metal ball rides on a plastic bearing surface, that is true also of many Heim joints that are Teflon lined.  I am also a bit dubious of some of their claims about poly bushings.  They repeatedly cited "squeaking" as one of the major faults of poly bushings, but if they are properly lubed with Teflon grease squeaking is a complete non-issue.  I have a track car on poly bushings that I greased/installed almost 20 years ago.  Not a squeak in 20 years.

 

My point being, hard to separate the truth from BS marketing with the R joints.

Edited January 16, 2021 by Ironhead

[Coelocanth81]

2 hours ago, Ironhead said:

I am interested in the R joints in concept, but I don't understand what makes them superior to standard Heim joints, other than costing 3X as much.  They do not appear to be "sealed" from dirt and moisture, and while the metal ball rides on a plastic bearing surface, that is true also of many Heim joints that are Teflon lined.  I am also a bit dubious of some of their claims about poly bushings.  They repeatedly cited "squeaking" as one of the major faults of poly bushings, but if they are properly lubed with Teflon grease squeaking is a complete non-issue.  I have a track car on poly bushings that I greased/installed almost 20 years ago.  Not a squeak in 20 years.

 

My point being, hard to separate the truth from BS marketing with the R joints.

 

If I remember correctly, R-joints use some kind of spring-loaded tapered sleeve that has a self-tightening effect to prevent slop as the joint wears. I also wanna say that the sleeves were grooved to promote a self-cleaning effect, and are made of Delrin(?) instead of teflon. They're definitely not sealed, but if they have the ability to shed/reject grit, it might bear some fruit for reliability. 

 

I agree with about their claims on poly bushings. If they're lubed correctly, they'll stay quiet. They've got a point about increased bushing "stiction" reducing the suspension performance. The upside of a bushing is also in the fact that it has some slop in it - which can save components from breaking in the event you hit a pothole in a turn, or some other "feature" that wouldn't exist on a properly groomed road course. In the end, I feel like a street car could definitely benefit from poly bushings over hiem joints in numerous locations. They gotta make a sales pitch, I suppose. 

Edited January 16, 2021 by Coelocanth81

[Coelocanth81]

4 hours ago, ///M3 & Z said:

I started thinking about the Heim joints after you mentioned it. There are a lot of them, 22 In the rear kit to be exact. If you planned on replacing those with the ridetech R joints it would cost you $1900 usd to buy enough of them. 

People seem to say they get contaminated pretty fast with dirt and road debris, would hate to have to be either cleaning or replacing that many of them.

Iv always also wondered what the cabin noise would be like with the struts and joints being right behind you inside. I like loud engine and exhaust sound but little bumps and vibrations I'm not a fan of at all.

 

 

That's what I counted, too. I definitely feel that the design leans on them a bit much for my purposes.  

  The cost of those R-joints are eye-watering - I think I'd only put them in locations that are external - leaving the interior joints to regular hiem joints - as they won't be subject to contamination inside the car.

 

With respect to the noise, I'd bet shock valving would be audible if there were no slack in the joints. Being outside the car, we never hear the noise that our struts make, but I can promise you they're not completely silent. The open hole in the top of the strut tower might also be an inlet for exterior noise, depending on how it gets sealed.

[clarkspeed]

On 1/16/2021 at 1:29 PM, ///M3 & Z said:

I started thinking about the Heim joints after you mentioned it. There are a lot of them, 22 In the rear kit to be exact. If you planned on replacing those with the ridetech R joints it would cost you $1900 usd to buy enough of them. 

People seem to say they get contaminated pretty fast with dirt and road debris, would hate to have to be either cleaning or replacing that many of them.

Iv always also wondered what the cabin noise would be like with the struts and joints being right behind you inside. I like loud engine and exhaust sound but little bumps and vibrations I'm not a fan of at all.

 

 

22 rod ends are not going to be light either. I can't help but to guess that F/R conversion will add more weight than any performance gains. 

[///M3 & Z]

I searched up a few videos on youtube of people using cantilever suspensions to get an idea of how loud it would be . Skip ahead to 9:26 in the video if the link doesn't already: 

https://youtu.be/L2FVxQjNXtA?t=566 To me that amount of sound while driving around town would be just ridiculious.

[jhm]

A member here designed and built his own version of a rear cantilever suspension several years ago.  It looked amazing, but I had the same impressions already voiced here (cost, complexity, noise, etc).  Still pretty amazing piece of work though....

 

 

[Ironhead]

I certainly want to support places developing parts for our cars, but after perusing the "track attack" setup I have to side with those thinking it is just....a bit much.  I don't mean just money, I mean the overall complexity to benefit ratio.  I think it is more of an engineering exercise than something that would make sense to buy and use, even on a cost-no-object track car.

 

A theoretically more advanced suspension design does not necessarily translate into a car that is faster or more fun to drive, and complexity can be a fault all it's own.

 

I am reminded of the story I mentioned earlier...of a racing team in a pro-level GT racing class doing advanced "ground breaking" design work on their suspension system that they thought would win the series, and while they dicked around with that another team running a live axle won the championship.

 

 

[Coelocanth81]

For a street car, excessive noise could be a show-stopper. I watched that video, but I’m not sure that the racket we were hearing was actually coming from the interior strut assembly.  It sure would be nice to get some in-car footage of a running setup to know for sure, though.

 

As for weight - I’m not certain what the apples to apples weight comparison is between a stock Z suspension and the track attack components. As long as the weight goes towards strengthened components and improved suspension articulation, I wouldn’t mind it - although, as a 2+2 owner with factory A/C, the lightweight train departed the station before my arrival!  Haha..

[AydinZ71]

1 hour ago, Ironhead said:

I certainly want to support places developing parts for our cars, but after perusing the "track attack" setup I have to side with those thinking it is just....a bit much.  I don't mean just money, I mean the overall complexity to benefit ratio.  I think it is more of an engineering exercise than something that would make sense to buy and use, even on a cost-no-object track car.

 

A theoretically more advanced suspension design does not necessarily translate into a car that is faster or more fun to drive, and complexity can be a fault all it's own.

 

I am reminded of the story I mentioned earlier...of a racing team in a pro-level GT racing class doing advanced "ground breaking" design work on their suspension system that they thought would win the series, and while they dicked around with that another team running a live axle won the championship.

 

 

my old engineering professor used to call us “sophisticated Taylor’s”. Meaning, our job is to CUT material, not add unnecessarily. His point was, anyone can “guess” conservatively enough to make something work. Engineering is the process of adding just enough material, complexity, etc. to get the job done, and no more. He also taught us to not “fall in love” with a design, and be open to continuous improvement and criticism. 
 

That always Resonated with me. 

[Coelocanth81]

Very good advice indeed!

 

He also taught us to not “fall in love” with a design, and be open to continuous improvement and criticism. 

6 minutes ago, AydinZ71 said:

 

[Ironhead]

3 hours ago, AydinZ71 said:

my old engineering professor used to call us “sophisticated Taylor’s”. Meaning, our job is to CUT material, not add unnecessarily. His point was, anyone can “guess” conservatively enough to make something work. Engineering is the process of adding just enough material, complexity, etc. to get the job done, and no more. He also taught us to not “fall in love” with a design, and be open to continuous improvement and criticism. 
 

That always Resonated with me. 

 

I love hearing stories/advice like that....

 

Another thing....if one wants to pursue the "ultimate" no-holds barred suspension design for a "Z", the logical first step would be to ditch the unibody and completely tube frame the car.  The basic Z body is notoriously flexy, and while a well designed cage helps, the production nature and era of the vehicle would certainly limit any gains that could be had from the ultimate suspension.

[AydinZ71]

39 minutes ago, Ironhead said:

 

I love hearing stories/advice like that....

 

Another thing....if one wants to pursue the "ultimate" no-holds barred suspension design for a "Z", the logical first step would be to ditch the unibody and completely tube frame the car.  The basic Z body is notoriously flexy, and while a well designed cage helps, the production nature and era of the vehicle would certainly limit any gains that could be had from the ultimate suspension.

I agree 100%! I think it’s important for us taking these cars to the next level, to know why they are the way they are. All a car manufacturer really cares about is how cheap, how fast, and how reliable the manufacturing process is (assuming the design/marketing actually creates a demand for the car). Therefore, stamped sheet metal spot welded together really fits the bill! Think about it... dozens of sheets of mild steel, stamped in a fury of Forges, transported with conveyors, assembled quickly with resistance spot welds. 
 

a race car and a production car have so little in common... I now have a much better appreciation for that restoring the race car. We start with a production car as a platform for many reasons, most importantly we can “add” to or modify something vs. starting from scratch. There are literally hundreds of dimensional decisions that Nissan has already made for us, for better or worse. Much more manageable then doing something from scratch and having to learn dozens of lessons the hard way. 
 

 

Edited January 26, 2021 by AydinZ71

[Ironhead]

1 minute ago, AydinZ71 said:

a race car and a production car have so little in common... I now have a much better appreciation for that restoring the race car. We start with a production car as a platform for many reasons, most importantly we can “add” to or modify something vs. starting from scratch. There are literally hundreds of dimensional decisions that Nissan has already made for us, for better or worse. Much more manageable then doing something from scratch and having to learn dozens of lessons the hard way. 
 

 

 

As a kid, I used to attend the IMSA GT races during the glory days of the racing Zs.  They primarily raced in GTU.  During the first few years I attended, all the GTU cars were production bodies with extensive cages and other mods to stiffen them.  Then suddenly, in the early '80s IIRC, everything changed.  I don't know if it was a change in the rules or just that the racing became more sophisticated, but overnight all of the competitive GTU cars were tube framed with fiberglass bodies....you know....nothing whatsoever in common with the production car except perhaps the engine block.  It might have been later than I recall...but pretty sure it was the 1980s.

 

That was the same time the prototype cars took over for GTX (Porsche 935 etc) and I began to lose interest in racing.  True production based racing is much more interesting.

[TUME]

Funny, about video and topic about cantilever suspensions, everybody goes nuts.

With real world it´s just "one pivot point more suspension" Okay, you can get some progressive behavior with pivot, but main reason with these things are: The fit in a low car.

That´s the main reason for use these things. Well maybe some street credibility, but that´s different story.

Edited January 26, 2021 by TUME

[caperix]

Can't you modify the arm pivot to allow more spring travel for a given wheel movement.  This could have some benefit on a low z car that has very little suspension travel.

[Coelocanth81]

On 1/27/2021 at 8:31 AM, caperix said:

Can't you modify the arm pivot to allow more spring travel for a given wheel movement.  This could have some benefit on a low z car that has very little suspension travel.

 

Depending on the design. If the pivot swingarm has different attachment points for the shock and strut-rod, then the leverage ratio of the spring and shock are adjustable. In doing this however, you’d want to optimize the wheel travel to match the full travel range of the spring and strut. There's likely only one ideal placement point for the respective items on the pivot, so a wide range of adjustment options may not prove as useful as they initially seem on paper.

Edited January 28, 2021 by Coelocanth81

[260DET]

Sometimes a reality check is needed and that can be provided here by looking at Z race cars and their results. The fastest Z's have always used the basic stock suspension, it's great that there are those who think outside the box and who are willing to put their $ where their mouth is, Once they do that however they need to turn a profit so they have to be commited to their product. What does not seem to be widely understood by potential users is the complexity involved in any suspension redesign. At the very least the actual dimensions and locations of all components needs to be established using proven methods. Until that is done we have what is basically promotional comment. Bye, getting real is often not popular.