Project EP3 Civic Si: Suspension Upgrades with Whiteline!


The front lower control arm is reinstalled.

You can see how the Whiteline bushing cants the lower control arm inward, which moves the control arm forward, increasing positive caster. You can also see how the cutouts in the bushing allow for the arm to pivot up and down, but the bushing’s solid center resists side-to-side and fore and aft movement.


The lower control arm is good to go!

The front sway bar is now ready to install. It is only 1mm larger in diameter than stock.

This makes the bar about 20% stiffer. The Whiteline bar is adjustable, and if the inner stiff position is used, the stiffness increases about another 20%.


Howard used Teflon tape and grease to prevent the Whitleine bars’ urethane bushings from squeaking.
 The front bar was bolted back in place.

With the Whiteline urethane bushings elimination of squishy rubber, squishy rubber that was worn out and hammered from many street miles, our car feels a lot better. Gone is the vague disconnection that the stock car had. The ride is just a little bit harsher, with harder bushings more road vibration comes through, but the car feels much more precise which makes it all worth it.

The Whiteline front and rear sway bars also helped by reducing body roll. Their adjustability will come in handy later when we dial-in the car at the track. With the rear bar being 5x stiffer than stock, understeer has been significantly reduced.

Now our car has a pretty solid foundation for more suspension mods we have planned. Stay tuned-in for our next installment, we get our car back on the road with some coilovers from Fortune Auto!



Whiteline Suspension

Enkei Wheels

Nitto Tire

Parts Shop Max




Hawk Performance Brake Pads


Centric Parts


  1. I installed the Whiteline RSB this weekend. WOW, I did not expect the dramatic difference in balance it would make. It really improved the car’s handling on the old stock suspension with +135k miles on it. Greatly reduced the plowing effect and the car will actually rotate now when pushed hard! Also seems to have fixed the weak rebound I was experiencing in the rear [but didn’t notice until now]. I love it!

    One question, the instructions from Whiteline said to sandwich washers between the bar and the endlink inner nut and locknut. Did you guys also do this? I’m using Hardrace rear endlinks and with washers in place the bolt is barely long enough to clear the width of the locknut, full thread engagement on the nut, but no extra threads left sticking out. I understand not having the nuts eat into the RSB, maybe I just need thinner washers?

  2. 2005 Honda Civic Si project. I want to upgrade the suspension on my 05 Honda to improve handling using the parts on your webpage. Can u provide a list of the items I will need to do the upgrade. Can I come in to pick up the parts for purchase? I would like to get the parts asap and come in to get them. I live locally in SoCal. Please advise.

  3. Reference EP3 Suspension Project. 30:41 video. WOW, I’m blown away! Not super mechanically inclined, but after spending a good amount of time researching, still can’t figure out whiteline special? bushing part numbers for the 12:06 time in the video (2 items), and 12:08 time (4 items) ? PLEASE PLEASE assist.
    Thank You for helping ALL the EP3 enthusuiasts ! You are the BEST ! Thank You Mike Kojima and the team! HUGE support for us Yes, I’m doing the majority of this project ! Super Excited

    1. At 12:06, those are the KCA424 bushings –
      At 12:08, those are the W63381 bushings. They only seem to be in stock on the UK website -

      Maybe because these chassis are not the most popular, it seems that Whiteline might not have the stock like they did when the Moto IQ video was made. It might be worth contacting someone at Whiteline to see what their actual availability on these parts is.

      Just purchased an EP2 here in Europe after owning an EM2 in the US and hope to make some of these improvements myself.

  4. Charles, the W63381 bushing is for the rear lateral arm the video has some photo discrepancies. I think David was looking for the 2 bushings being pointed a few seconds earlier in the video. If that is the case then I believe he is looking for the 2 front lower control arm bushings. He’ll have to confirm for us that’s what hes after.

    As for W63381 being sold out I think the main reason they are possibly discontinued is the abundance affordable aftermarket arms that replace the thin oem arms like these

  5. read the whole article on this website, and have watched the video several times over. i purchased the whiteline camber bolts for my front suspension on my 2005 honda civc si. per the whiteline doc that came with the bolts i installed them on the upper strut damper bolt. and put the apex of the lobe pointing to the inside of the engine bay for a `A` camber effect.

    is this how yall installed the bolts? i did not see any video footage in the youtube video of the bolts installed and their orientation nor did i see any pictures of the bolts within this 7 page article. look forward to your response.

  6. hey Mike, if I farm out this project to a local mechanic, how many hours of labor roughly speaking do you think all of this requires? and roughly the cost of parts?

  7. Good day
    In regards to the trailing arm bushings, it was mentioned that they used the OEM rubber trailing arm bushings, but what about the harden rubber trailing arm bushings from hard race or the powerflex trailing arm bushings

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