Project Acura RSX Sleeper, Buttoning Up the Project With Suspension!

We left off in our last edition of Project DC5 RSX with some killer brakes by Stoptech that brought our cars stopping power in line with our fantastic 300 whp naturally aspirated 91 0ctane pump gas K24 engine. Since the goal of our car is to build a subtle and stock looking car with outstanding performance, we now have to piece together a suspension for our car that gives great performance but is totally driveable in daily use with as few as possible annoying characteristics. If you want to see what we have done so far in total to our car you can check it out here.

One of the issues for building the suspension of the DC5 is that the handling in stock condition is pretty horrible. The DC5 shares most of the suspension parts and flaws of the much-maligned Honda EP3 Civic. The biggest issue is the horrible bumpsteer caused by the unbelievably poorly designed front steering geometry and an odd center tie rod attachment point for the steering rack.  You can see how we fixed some of this on our EP3 project.


Most of the time, when improving the handling of a car, the best starting point is a good set of coilovers.  Not too many companies make good coilover for this platform but we found that KW Suspension makes a set of Variant 2 single adjustable coilovers for the DC5 chassis.  The KW part number for these is 15251001.  The damping for the Variant 2 has a single adjuster on top of the shock shaft which affects mostly the low-speed rebound.   In order to keep things smooth and quiet, we opted to retain the stock Acura rubber isolated upper mounts and simply replaced our old parts with fresh genuine Acura parts. The front spring rate is 5 kg, up from the stock 3.2 kg.

Since we are going to be running the stock upper mounts instead of an adjustable camber plate, the KW front struts have a great feature. The upper strut to knuckle bolt is slotted and has an eccentric so camber can be adjusted at this lower point.

The steering arms are welded to the strut body which is in our opinion a good feature. Some other RSX struts have the steering arms on a threaded collar which can come loose and cause wandering due to toe change and screwed up Ackerman.



The rear shocks are also single adjustable. Like the front struts, we will be using the stock rubber isolated mounts. The rear spring rate is 9 kg up from the stock 5.3 kg.


    1. Ok so I’m not sure what your ask but I can explain what a rsx is a Acura RDX is a American version if the Honda Integra Dc5 there the same car with different badging.
      Hope this helps

      1. No – I mean that in the sense of… Honda built some of the best handling FWD cars ever from the factory… and then they built this? It’s just astonishing that Honda, of all companies, went backwards like this.

    2. From what I understand, to save development costs the firewall and front suspension module were taken from some Japanese van thing. Hence the front suspension geometry that has no thought to anything other than to attach the wheels too! This and the EP3 have the worst bumpsteer of any modern car that I have ever driven.

      1. The steering rack is interesting though, in the sense of I can think of a use for it, on something weird enough where the control arm pivots nearly meet in the center. Metro 6R4 inspired thing, if I ever get crazy enough to build something like that.

      2. it shares the same suspension and steering as a honda element. having owned both an element and an rsx, i have to say they handle pretty similarly.

        in the element community, this was awesome as you could use similar components from a “sportier” vehicle on your crossover SUV.

        conversely, as an rsx owner, it’s kind of unfortunately that your sport compact car shares a lot of components with a crossover SUV.

  1. Has anyone tried to develop a mounting section that is longer so that the inner tie rod pivot location would be more outboard? This might result in too high of a torsional force on the rack center I suppose.

    1. Yes, actually the guys at SHG Motorsports did exactly that for their race car. They were able to get the toe change to under 1/8 for the entire suspension stroke.

  2. After sometime with the suspension setup, what are your thoughts on the inverted tie rod ends? In the past people have said that it had created more bumpsteer unless you are very very low. I do have RCA’s so I’m wondering if I should consider these. My downpipe is contacting the tie rod slightly because the angle is so high up, inverted would remedy this issue for me possibly.

    1. If you don’t get and install both the roll center correctors and the bump steer correctors together, you will have horrible bump steer. That happens all the time. People don’t understand how this stuff works!

  3. Sorry to bring up an old thread. I have a DC5R which shares most chassis components with the RSX. I’ve seen conflicting opinions with regards to how the inner tie rods should be angled. Ideally for the best ride quality, should I be aiming to get the tie rods as flat as possible or should they be angled, and if so, angled to what extent?

    1. At the same angle as your lower control arms. If your lower control arms are pointing upwards or are horizontal with the floor, try raising the car until the arms are slightly pointing down. This will allow better suspension geometry upfront. would also highly recommend the extended balljoints, the equivalent or better as mentioned in this article.

  4. We keep being told how bad the bumpsteer is but no bumpsteer graph being presented in comparison. I have a bumpsteer gauge. DC5 and EP3 don’t have horrible bumpsteer. They just don’t respond the same when lowered without corrections being made. And you want the tie rods to have an angle because it’s attached up higher on the coilover. The coilover steering arm travels inward towards the chassis as you compress. Having the tie rod angled is what helps the tie rod end keep the same place inwards towards the chassis. If it’s off too much you’ll have major toe changes. Now imagine how much slower the tie rod end moves towards the chassis if you make it horizontal.

    Even SHG and PCI racecar don’t use inverted tie rod ends.

    1. The essential reason for moving the outer tie rods is that the roll center has been raised and you need to move the tie rods when you move the LCA outer pivots or else you get horrible bump steer. The stuff PCI sells moves the inner tie rod with a vertically adjustable slider, essentially doing the same thing but even better as inverting the tie rods moves them too much, you go from toe out under compression to toe in. The PCI parts let you adjust the tie rod height for the toe curve you want. Had this part been available when this car was built, we would have used it instead along with their heavy-duty slider. The SHG race car had a fabricated long slider and short tie rods to place the inner tie rod close to the imaginary line between the top strut mount and the inner LCA pivot, reducing bump steer to a very low amount. In addition, the inner and outer tie rod ends could be adjusted up and down so you could tailor the curve to your preference. SHG never produced these parts for sale even though I tried to convince them to. We will probably go to the PCI parts in our EP3 project car and this car when we have the time.

  5. A bit late to the game but wondering if the polyurethane bushings are absolutely necessary or could i make do with hardened rubber bushing for a more daily car driven car since Im worried about a stiff ride or loud squeaking and for the same purpose would it be more cost effective to go with the inverted tie rods over the PCI adjustable tie rods. Also would it be alright to go with something other than KW like BC Racing or Fortune Autos.

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