DailyTrackDc2

My Apologies for cut and pasting my build from another forum but I've found Honda-tech to be a treasure chest of knowledge and wanted to share my Dc2 build with the community.

Hi All,

I recently moved to a new city and as many of you know yourselves the main concern for any car nut without a car is what car to buy next!

I was initially just looking for a daily driver and after weighing up the cost and performance of a few cheap Japanese cars I purchased a Dc2 Vti-R (GSR) with 280000km's on the clock.

When I brought the car it was 100% stock and drove fine if a little loose and rattly. After driving the car for a few months I started researching modified Dc2's and Type Rs as you do. I originally intended to leave the car stock but after reading some of the great build threads on the web I convinced myself modifying the car was a good idea. The Dc2 Type R is touted as the "best handling FWD ever" and I wanted to experience the full potential of the Dc2 chassis.

Given the mileage of the car I wanted to refresh the essentials. I started by replacing the timing belt, water pump and rocker cover gasket.

The car then developed a squeal under brakes, I pulled the wheels off and sure enough both the front and rear rotors were heavily worn. I replaced the pads and rotors all around with cheap Repco replacements. Looking back now i wish i had researched brake pads a little more and gone with a more performance orientated set of pads.

I found a set of Tanabe Street sport struts for sale on ebay and decided they were the way to go because they reuse the factory top hats. As I intend to daily the car I want to keep the rubber damper bushes and spring isolator.

I ordered a combination of Mugen and Spoon hard durometer rubber top hat bushes and replaced the bushes in the UCA and LCA. I sourced a set of Hardrace adjustable camber and toe links for the rear, these let me set the toe and camber back to stock settings.

After a short time on the forums I noticed a large number of DC2's running the ASR subframe brace and 23mm Type R rear anti-roll bar, i picked up the bar from ebay and the brace from ASR. I was pleased with the quality of the ASR brace and found it straight forward to fit.

I brought the Type R wing and lip from ebay then had them painted by a local paint shop. I found the wheels for sale in Sydney and made the seller a cheeky offer which to my surprise he accepted. They are genuine Enkei Sport ES-Tarmacs 15x7 +40. The wheels feel light but i have yet to actually weigh them.

I'm really happy with the handling of the car now. I will continue to tweek the car here and there but my intention is to keep it on the road as much as possible.

Thanks










I have been driving the car everyday and fixing small issues as i go

The car had a small oil leak from around the V-Tech solenoid, you know that stain on the bellhousing that never goes away no matter how many times you wipe it off. I replaced the solenoid o-rings and de-greased the front of the gearbox and block while I was in there.

The Tanabe spring and damper combo was designed as a upgrade for the Type R and as such the rear dampers have the eyelet lower mount designed to fit with the Type R LCAs. When i installed the front shocks I wanted to drive the car so I swapped the Tanabe rear spring onto the GSR rear damper so the car would sit level until I got some Type R LCAs. The car drove terribly like this and the rear felt really unstable. I attributed this to the Kenda Komet rear tyres I was running but when I finally got the Type R rear lower control arms installed they completely transformed the car.

I'm not sure if the issue was lack of preload on the rear springs due to the oem dampers being longer than the Tanabe units or the heavier damping or the stiffness of the hardrace type R LCA but the resultant of getting those components installed has restored balance to the chassis and increased grip in the rear tremendously. The car can now be pushed right to the limit and when you exceed the tires the chassis responds really predictably. I took the car for a drive in the hills and was blown away, it has great turn in and feedback to the driver.



I made some centre caps for the Enkei rims to add to that 96 spec look that i'm going for, I think the centre caps make the car look a bit tidier overall.

I've installed a short shifter with 50% reduced throw and rebuild the shifter assembly with urethane bushes. I added a 100mm extension to the shift rod and now it has about the same throw as stock but the **** is much closer to the steering wheel; cycling through 2nd and 3rd feels really good now.

I found this picture on the internet, it's a CRX i believe. I really like the clean functional look I think i'm going to try pick up a fixed back bucket seat and harness as you really can't hold yourself upright while cornering anymore.



I also have an Airbox set up in the works. Ill post some pictures when it arrives and i get it installed.

I purchased a OEM Type R exhaust last week. The pipe work has already been coated in a hi-temp paint and it came with the 2.5" JDM high flow cat which is a bonus. The muffler is a Fujitsubo Legalis R which i'm told sounds really good. I'm looking forward to getting it installed.

I don't want a loud or drone-y exhaust just something a bit more aggressive than the factory vtir pipe. I'm undecided on what to do about the headers, I'm thinking about Private Label Toda replicas.

The car snapped two exhaust studs last week, this looks like a major pain in the *** to fix!



The exhaust manifold has overheated and warped snapping the studs as it's moved. The manifold needs to be faced(or replaced) and i've got to replace the studs. One of the studs snapped off inside the head making removing it a real problem as we can't just weld a nut to the end. I will source a 90deg drill and attempt to remove the broken stud with an easy out.

Since the header had to come off to fix the studs, I took the opportunity to weld a baffle plate into the sump pan. After welding the plates in i cleaned the welds with a wire bush to remove any loose bits then rinsed the sump out with brake cleaner followed by some old engine oil before refitting it.

I replaced the sump seal and gave the whole area a good clean.



Here's a blurry teaser of my Airbox set up.



The Airbox consists of a Mugen copy fiberglass Airbox that will house a K&N 3" Inverted filter. The reason i went with a cheap copy is that i have decided to covered the filter housing in heat reflective tape. It just seemed wrong to buy a Genuine Mugen Airbox then cover the beautiful carbon and logo devaluing the airbox. I sourced the Mugen Copy air box from China and unfortunately it is really poor quality, out of the box it didn't have provision to mount the filter inside and the fibreglass is really rough (it's ok on the inside). No matter though, it will serve my purpose as a duct from the bumper to the engine bay and cost a lot less than a genuine Mugen. It came with a bell mouth not shown here. A good reminder you get what you pay for!

I will fabricate an aluminium flange with 76mm tube through the back and make it all work with the rest of the factory pipe work (are most full tube CAI 76mm?) .The heat reflective tape is pretty neat, this product is claimed to reflect 80% of heat up to 850 degrees!

I've been continuously working on the car since the last update.

It's now got the Type R exhaust system installed, initially I modified the V-Tir header to fit the cat back system but then I managed to acquire a b18c7 Dc2r header and swap that on. I modified the secondary and It's 2.5" from the secondary collector all the way back now. My butt dyno tells me the exhaust has made a difference and if in the future I head down the intake/cams/tune road it will support those mods too.

I entered the car in the Exe Haunted Hills Hill Climb event, i was really happy with how the car performed and had a lot of fun chasing the times of a very quick EF!


Credit to C2888 of Exe Forum.


Credit to C2888 of Exe Forum.


Credit to C2888 of Exe Forum


Credit to Peter McG

After Haunted Hills i got back to the garage, put the car on the hoist and gave the car an inspection as you do and found the left hand side front upper control arm had twisted!

In addition to the control arm damage i inspected my tyres and found the scuffing on the front tyres quite far down the sidewall. I recall the car pushing the front end quite badly on the downhill sweeping corners toward the end of the course and that driving impression combined with the tyre wear led me to the conclusion that i wasn't running enough camber upfront. I was running pretty high tyre pressure on the day so i don't think it was a tyre pressure issue.

I looked up my last wheel alignment sheet and found we'd only given it -1 deg camber up front, after reading up on what fast FWDs should be set to I decided that I should be running around -2.5deg camber and the car was lacking castor as well.

Since the control arm needed replacing anyway i picked up a set of Hardrace adjustable upper control arms.



I fitted all the remaining washers from my whiteline castor kit



I made myself a camber gauge at work and set the front camber to -2.5, with the washers installed castor should now be somewhere around 3 degs. Something about the installation of the washers to adjust castors doesn't sit well with me and i think the front LCA set up could be done better, expect some interesting updates to come in this area.

I wound in another half a degree negative camber at the rear taking the total rear camber to -1 deg. Front and rear toe was the reset at 0.

Interested to know how the new wheel alignment would change the car I booked a spot on Tampered Motorsports up coming Trackday at Winton Raceway.



I had some trouble with my trailer hire in the morning causing me to miss the first session but after that the day went without a hitch.

I managed a 1.50.7 which i was reasonably happy with. The car has a great attitude on track, It never fails to turns in and rear slides out just enough to help the car turn.

I'm still very much a novice when it comes to driving the car so it's hard to differentiate between poor driving technique and vehicle behavior but if i had to be picky i feel the car struggled with understeer in low speed corners and still feels like it's overwhelming the outside tyre. It would be interesting at this point to drive a dc2 with an LSD to seem what difference it makes!


Build thread now up to date, stay tuned for further progress on this car!

ed rex

that is a very clean car i like it alot

Spartacus2234

great looking teg. I'm definitely following this thread. Keep us updated !

JDMTERRY

Nice car, although trying to read it gave me a huge headache..

B serious

iTrader: (1)

A LSD and shorter gears makes a huge difference. The LSD is a big part of the reason that the ITR handles so well.

DailyTrackDc2

Thanks for your responses and encouragement. I've edited some of the above to try and make the thread a bit easier to read.

Since the track day my brakes have been a little soft and lacking in bite. I did feel some pad fade during the track session but i'm not familiar with what long term effect that has on a car's brakes.

I've ordered some super blue brake fluid and will get that bleed through the car in the weekend. Hopefully that brings back my pedal feel otherwise ill have to sort out some new pads as well.

I've got an interesting update on the way, i'm just taking my time to get everything straight before i post it up. Here are some teaser pics!

B serious

iTrader: (1)

Soft pedal during hard braking means fluid boiling issues.

Firm pedal but no stopping power means overheated pads.

I didn't catch what pads you're running. But for your setup, something like Hawk HP+ front and HPS rear or Stoptech street performance all around would be good.

Nice that you can still get ATE superblue. They outlawed it in the US literally because it is blue and brake fluid should not be blue :/

Not sure if this mod has made its way to Australia yet...but people use 97+ spec ITR calipers and brackets (the ones that go with the 5 lug brakes) coupled with pads for an ITR and 11" mini cooper rotors for the front. EP3 rotors and ITR calipers/brackets/pads for the back. (assuming you still have 4x100 brakes).

That would allow you to keep the wheel selection afforded to 4x100 lug patterns whilst having the braking performance of the ITR.

DailyTrackDc2

On the track i experienced pad fade, ie firm pedal but no stopping power. However driving the car the next day the brakes seem to have lost some "bite" and the pedal feels different to before the trackday.

Can you glaze a set of pads? or is it once they are overheated they're toast.

Thanks for your recommendations! I will look into those options. I have read about the ITR caliper/mini rotor combo.

Do you have any experience driving with gsr brakes vs ITR brakes? Is it a substantial upgrade?

I think the Willwood calipers are reasonably priced but have been warned the pads for Willwood calipers are more expensive.

B serious

iTrader: (1)

I have owned a few 5 lug swapped civics and a 2001 ITR. I have also owned various civics, EM1's, and Integras with stock brakes (4Dr and 2dr).

Yes...there's a huge, night and day difference in braking power.

DailyTrackDc2

Thanks for sharing your experience. You can read about these swaps but unless you experience the changes first hand it can be hard to quantify the difference.

DailyTrackDc2

So last week I posted a couple of screen shots from Susprog3d a cost effective Suspension analysis program I have used to model the Dc2’s suspension.

I’d like to tell you I used a co-ordinate measurement machine to measure all the points, (I did briefly consider it) but in the end the measurements were taken with tape measure, steel rule, string line and steely eyeball.

I’m confident the dimensions are accurate enough for my purposes and that the model truthfully represents the dc2 suspension

The dc2 runs double wishbone suspension up front with a unique trailing arm set up in the rear that features a camber arm, lateral link and a forward toe arm.

You can see these features are represented in the suspension model.

Susprog doesn’t have a polished user interface and requires the user to do a bit of work to get the information presented in useful form.
The benefit of this is that you have the flexibly to plot the data anyway you like.
I’ve now got Camber, Toe and Roll Centre data for the front and rear suspension and this information will help reduce the confusion when ironing out handling issues.

My main motivation for measuring up the DC2 was to investigate roll centre placement and find out what the roll axis is up to with changes with bump and droop.

It was this photo of my car at Haunted Hills combined with my experience in the car at Winton that kept nagging at my inner Engineer to find out what the car is doing



I’ve put the next three images together to illustrate what I found

At near stock ride height the factory roll centre front and rear are both well above ground level and the roll axis slopes downward toward the front of the car. This is generally accepted as the desirable set up for predictable handling



I found that as ride height was reduced the roll centres moved downward with the rear actually having greater vertical movement (due to the arch of the shorter links) this results in an almost flat roll axis at ride height.

If you look at the pictures of my car you can see that it is not excessively low yet that car is what i based my "lowered" ride height on.



The problem occurs when the car goes into bump. The front RC plunges below ground level and leaves us with a long roll couple. Roll couple being the distance from the car's centre of gravity to its roll centre



White DC2 Pictures Originally from www.Fastcar.co.uk

In simple terms the greater the roll couple the lower the cars roll stiffness (geometrically).

If you’re having trouble following me, check out the link below.

https://www.youtube.com/watch?v=bLcDN-qCpYI#t=04m39s
Video of DC2 competing in Swiss Hillclimb 2013

In the video the dc2 is comes into the right hander heavy on the brakes, all the weight is transferred to the front and the front suspension is compressed in bump. As the driver turns in, the car pitches about its roll axis, overloading the front left. This contributes to the car understeering and delays the driver from getting back on the throttle. For the sake of this discussion let’s not argue over driver technique.

The relationship between the centre of gravity of the car, its roll centre and roll couple is shown in this handy diagram I have borrowed from elsewhere on the web.



Now what?

Well I can buy front roll centre adjusters from Hardrace or Mfactory or J’s which is great and i’ll be picking some of those up in the next week or so.

The problem is, if you just increase the front roll centre, you will end up with an inclined roll axis toward the front of the car.

I think maybe the reason roll centre correction parts get mixed reviews on the forums is because although they reduce the roll couple across the front axle the resultant car is unbalanced

I believe the common practice of running high rear spring rates on Dc2 is reflective of this.

My plan:

I can correct my rear roll centre by modifying where the rear LCA mounts to the rear upright

I brought myself a set of trailing arms and measured them up



I have designed a weld on bracket to drop the outer LCA mount



While I’ve got the welder out I figured I might as well gusset the inside of the trailing arms to increase their stiffness.



The removable plate is there to enable the handbrake cable to be fitted

Everything is ordered and I should have the trailing arms fitted sometime in the next few weeks.

I could be totally wrong about everything, after all thousands of people have been campaigning dc2s in all forms of motorsport all over the world with no issues. This is just something that I find interesting and it will be satisfying if it works.

Thanks!

B serious

iTrader: (1)

Its impressive what you've done. I think, however, the best way to mod a car is reactively. It will be easier to modify it with the knowledge you've gained since you won't be making blind changes. But that can also hurt you if you're going against the seat of your pants feel of the car. If engineers had the final say in making a car fast, the concept of talented and knowledgeable drivers would be thrown out in lieu of theoretical data. It would be a total ******* nerd fest and nothing would work because someone forgot to take into account the earth's rotation or some other infinitely ineffective variable.

^ I say that in the most endearing way possible.

I wouldn't over think it. I try to keep it simple. If the car understeers, for example, you might use your knowledge toolbox and say "I know what might work".

I would change nothing, however, till you're confident enough that you drove the car well enough to make changes based on this data and that your changes are going to be the cure. Who knows...maybe a car with a shitty rear roll center is inherently faster BECAUSE of its roll center shittyness.

Then again...Maybe you're on to something and people will be beating down your door for your rear roll center adjustment/stiffener parts.

But...again...just drive. Figure out the car as you go. At any given track event, there's going to be 300 hillbillies, (idk what you call hillbillies down under) who still think the world is flat, that will still manage to go faster than you because they're adjusting the car by feel.

Tight-R

Definitely an ambitious undertaking, excited to hear some feedback, which I hope isn't bias due to the idea being yours.

DailyTrackDc2

Thanks! I understand your sentiment and whole hearty agree with you. I don't nearly have enough seat time to string consistent lap times together and yet I'm looking at making a radical change.

Making these modifications and testing what i think i know about suspension is the reason i'm doing trackdays. I'll keep my original trailing arms just in-case I've made a detrimental change.

I guess it's a little more involved than bolting on a set of front upper control arms or a strut brace but it's not too bad.

Here some pictures of my first Honda project











Thanks

B serious

iTrader: (1)

Indeed.

B_Swapped93

I love seeing tube frame chassis cars! we have a few that run at our time attack events. Very neat and a Skyline R32 in the back ground is it yours also?.

GagnarTheUnruly

iTrader: (3)

You, sir, are a genius. Looking forward to seeing your results. Maybe a solution to the high rear spring rates we all put up with?

DailyTrackDc2

Haha oh man, my apologies if I come across that way. Just trying to share some interesting content.

B serious

iTrader: (1)

Lol. Not at all. I'm just jealous. Great work on that frame car.

DailyTrackDc2

By my calcs increasing the rear RC will increase rear roll stiffness 22%. The roll centre will also have a smaller range of movement, making the roll stiffness more consistent.

DailyTrackDc2

Thanks! I had four years invested in the car and never got to see it run. I learnt a lot about design and fabrication through. When I moved countries I packed up all the expensive bits and brought them with me. We scrapped the frame.

The R33 GTR was not mine, just another car in the warehouse

DailyTrackDc2

In the past week i've tidy'd up a few interior items that had been bugging me.

I removed the factory clock for the last track day. I figured that with a time read out on the headunit, GPS and my phone I can live without a dash clock. I want to keep the car presentable so I fitted a ITR clock delete panel.



I removed the rear seats for the track day as well, i've decided to leave them out permanently and will probably get a filler panel made up to level out the boot shelf and protect the top of the fuel pump. I will then get a new piece of carpet made to cover the whole lot.



I laid this heat reflective/sound deadening product over top of the seat base panel to try and keep the noise of the fuel pump to a minimum



I've changed the rear section of the console to the type R version in preparation for new seats



I brought a Type R boot bar under the impression that the Vtir chassis had the provision to mount one. It turns out they don't. With a small modification I mounted it slightly further forward onto the rear "chassis rails"

DailyTrackDc2

Gusset plates have arrived, I should have the LCA plate in the next day or so. Hopefully i'll have pictures of the finished trailing arms this weekend

DailyTrackDc2

I found a picture of my twisted upper control arm, a parting gift from the Haunted Hills track.

Tight-R

How the f......?