Retrospective – R.CREW RACING’s World Challenge EK (in year 2004/2005)

Updated by Frank M. Lin on 12/15/2011 4:26 pm – Thoughts about this car in 2011.  In retrospective, this was a bitter weekend for myself.  This was Dan’s car, and both Alex and him performed majority of the work on it.  I did a couple of minor things like taking the car to get it aligned and bring it back.  I did however, pay for the entry fee to the race.  I also bought a fresh set of Toyo Proxes RA1 sized 235/40/17 just for this event, and I treated the guys to lunch at a beautiful Sonoma Winery (no big deal, Dan bought me lunch all the times and would never let me pay my own share, unless I was paying for everybody lol).  I spent about $1300 but the car just never ran right on the Oct. 08/09, 2005 Honda Challenge weekend.

Several weeks later, when Dan and Alex finally got around to disassemble the car they figured out the flywheel/clutch assembly was not installed correctly, hence the clutch issue we had.  There was also problems with the wiring setup for the MOTEC causing it to be way down in power.  All resulted in a bad showing for us.  Prior to this weekend I had pleaded to Dan that we must put in a test day before the actual race weekend.  I want it to be perfect.  But Dan had a lot of shop business to attend to and he could not get me the test day that I asked for.  I didn’t feel confident going in to the weekend because the car was already having issues at the Buttonwillow STUSA shake down (terrible handling, and shifting problem).  Dan kept on assuring me come the Honda Challenge weekend everything was going to be fine.  Well, it was not at all.  I was really frustrated inside, but I couldn’t complain too much because it was Dan’s car, and he was kind enough to let me race it.  But at the same time, I put in $1200 for the weekend (nothing compare to what Dan has invested in this car though, easily over $17,000) but had a terrible experience.

Weeks gone by, and Dan asked me if I want to race Honda Challenge seriously.  I said, of course.  He said, give him $10,000 and he will do it.  I asked Dan, sure, but can you explain to me what that include.  Dan got irritated by my questions and quickly said, just forget it.  Alex pulled me on the side and said, dude you should have just said yes without hesitation.  Alex asked me if Dan have always taken care of me.  I said yes indeed.  But I said I want it to be fair.  I’m more than willing to pay for my fair share into this.  All I needed was for Dan to clarify for me what $10,000 would include.  The biggest question I had was was this $10,000 the cost for me to rent the car from Dan?  Did that include transport, food and fuel cost?  Did that include wear items, and consumables (brake pads, oil, tires)?  Most importantly, did that include the entry fees to the entire season of Honda Challenge.  At about $350 per race weekend, times that by 9 weekends would mean $3150 entry fee as well.  If it was all inclusive, I felt like that was too good of a deal and it would be unfair to Dan.  I want to make it fair.  But Dan seemed offend at my simple questions and he just brushed me off…

That was too bad, because I know Dan and Alex working together would make the car supremely competitive in a short amount of time.  With their full support I can concentrate on driving and, I am sure I can be competitive against the other drivers at Honda Challenge.  Maybe it was misunderstanding, or maybe I hurt Dan’s feelings by not accepting immediately…  it did not work out in 2005 and slowly Dan starting parting out the parts out of the EK and I don’t believe it was ever tracked again.

I remember on the forums people were putting us down about the lap times…  Considering the issues we had, the car did okay.  We did 1:54.x and it wasn’t even WOT at all, with poor handling as well.  Any real racer knows cars have bugs that needed to be iron out…  I knew for a car that this car was fast.  I will dig up the photos soon but before this car was changed to K20A power, it was in another trim.  The motor was powered by B18C5 with Toda ITB’s.  I think it had ITR transmission with 4.9 final drive.  It had the rare ATS single disc carbon clutch, and it ran the simple Spoon 4 piston ITR brake setup.  TEIN N1 suspension setup, ITR sway bars front and rear.  We ran 16″ Mugen wheels on some 16″ Bridgestone high performance street tires.  The car only put down 185 whp but the power band was smooth and it ran really well with the final drive @ 9000 rpm.  Even though we were on street tires, at an Audi Club day, we SMOKED EVERYTHING.  I played lead and follow with a full race 550 whp AWD Audi 4000.  He would pull easily some 20-30 yards on each straights but under braking and a corner later we would be on his ass again.  Eventually even he had to wave us by…  it was absolutely sick.  Handling was beautiful and we carved the corners so hard.  I’m certain in the K20A EK trim it was NO WHERE near as fast in corner speed.  The newer setup was TEIN RS if I recall…  for whatever reason it just did not work well…

When Dan made the switch to K20A, I think he just made way too many changes all at once…  and ruin a beautifully balanced car.  I also forgot to mentioned that, Spoon had couple of staff at this Honda Challenge weekend due to their business dealings with their USA dealer OPAK Racing.  They saw Dan’s EK and was very interested about the K20A swap (which was not done in Japan at the time yet).  The Spoon staff politely asked if he can take photos of the installation and he proceeded to asked many questions about the swap to Dan.  Not long later, this Spoon K20A EK9 came out.

I notice that the lap time of 1:03.x is a bit slower than Spoon’s own B series powered EG6 though… I remember they had ran 1:00.x flat with that setup with R compound tires. i speculate the stock suspension just don’t work well with the much taller 255/40/17 (25″ diameter vs. 23″ of 205/50/15)… the car sounds great, but the acceleration don’t seem to be all that strong though? perhaps it’s not a strong K20A engine…

Written by Frank M. Lin, published on back in 2004/2005:

This car was built with the intention for the SCCA sanctioned World Challenge competition.  It serves as the real world testing ground for products and services offered by R.CREW RACING.  World Challenge allows seam welded chassis so the whole tub was stripped down to the bare minimum and every seam on the car was spot welded.  Recently Honda club road racing has picked up steadily and now the car has two additional classes where the car can compete in.  They are the NASA Honda Challenge H1 class and the new 2005 SCCA Honda Cup class which is currently in Southern California only.

All preparation are done in house at R.CREW RACING including the full chassis preparation.  Fully stripped, seam spot welding, race cage construction, MOTEC ECU wiring install, dyno tuning, suspension corner balancing, custom 3″ mandrel bent exhaust, front splitter, rear wing… etc.  The race car features numerous R.CREW K series swap products as well:

  • R.CREW 304 stainless steel 4-2-1 header with merge collectors
  • R.CREW PIMP (Power Intake Manifold Plenum)
  • R.CREW short shifter
  • R.CREW bolt-on shifter box adapter

The power plant is the Japanese Integra Type-R DC5R K20A (2.0 liter inline four) with 6 speed manual transmission.  Currently the engine makes 232 hp at the hub and 162 ft-lbs of torque.  This was done at the R.CREW’s shop dyno the Dynapack 3000 which is calibrated with output nearly identical to the popular Dynojet 248c.  The car meet the Honda Challenge minimum weight of 2350 lbs with driver.  The transmission is the standard DC5R close ratio 6 speed manual.  The final drive has been changed from the stock 4.7 to 5.0 for improved acceleration.  With the 235/40/17 sized tires the following data is calculated:

DC5R 6 speed Transmission Box, 5.0 final drive, 235/40/17

final drive
max speed
@ 8500 rpm
rpm drop
from redline
rpm in
next gear
1st gear 3.266 39.2 mph 2957 rpm 5543 rpm
2nd gear 2.130 60.1 mph 2446 rpm 6054 rpm
3rd gear 1.517 84.4 mph 1709 rpm 6791 rpm
4th gear 1.212 105.6 mph 1683 rpm 6817 rpm
5th gear 0.972 131.7 mph 1678 rpm 6821 rpm
6th gear 0.780 164.1 mph n/a n/a

Aug. 06/07, 2005 – STUSA initial shakedown report @ Buttonwillow

last updated 08/18/05

We have just shaken the car down in at Buttonwillow.  The K20A swap was completed just recently and the testing weekend went well.  It was very warm air temp 110F on Saturday and just over 100F on Sunday.  The car was perfect mechanically.

However, we have discovered couple of small bugs which are being ironing out.  Some of the problems we encountered were the reverse gate lock solenoid out was not working which is usually powered by the Honda ECU.  We will wire in a switch button to manually lock the reverse gate out.  With out the reverse gate it made shifting interesting.  If you push to the right too hard, you can not shift “up” since there’s nothing above the R gear.  If you push lightly to the right you are not positive if you are going into 3rd (which would be very bad) or into 5th.

Handling wise the car was behaving strangely.  When we tested the car at Sears Point last time it handled flawlessly.  However it was on B18C5 drive train and 16″ wheels.  For this weekend there were many changes made that could have affected handling.  They include the massive STOPTECH brakes which requires moving up to 17×7.5 wheels running 235/40/17 gumballs.  With such a large size tire we had to raise the ride height for tire clearance.  We are also running MUGEN 2 way LSD.  The car was ill handling on Saturday with very poor turn in and notable mid turn and exit push.  Once we learn that the tire clearance was okay on Saturday, the suspension was lowered much closer to the previous ride height.  The initial turn in immediately felt better due to better toe from correct ride height from the last alignment.  However the mid and exit push is still there.

Once we return to the shop we corner weighted the car and checked for suspension travel.  The front suspension running out of bump travel which can cause understeer.  We give the car more camber now, with 4 degrees up front and 2.5 degrees on the back.  Zero toe front and back.  We plan to test the car again before August is over and if all goes well the car should be ready for competition by September.

work in progress…

Oct. 08/09, 2005 – NASA maiden competition report @ Sears Point

last updated 10/10/05

Saturday, Oct. 8th, 2005

practice session – 8am, track still cold and cars were out for 2-3 laps already and going full speed.  since we are just using this weekend more like test days to collect additional data, we just used brand new full thread tires.  car was super tail happy in lap one on dead cold tires it was a little unnerving hoping i don’t spin the car out and trying to keep from getting in people’s way.  do a few laps to check gauges, general feel of the car it was alright but the laps were just 8.5/10th speeds.  trimming the bump stops seems to have solved the understeer problem from Buttonwillow.  we didn’t have the transponder wired up yet so no lap times.  the car had 31 psi cold pressure to start with, fronts warmed up to about 38 and rears 34.  everything seems ok.  when we signed up 2 weeks ago we entered as H1 car.  but R.CREW was doing engine development so the car has couple of illegal parts, the camshafts, and 12.5:1 high compression pistons.  everything else is legal.  in reality these mild cams and pistons only yielded 8 whp (on dynapack) and 2 ft-lbs of torque peak than a stock k20a.  to be legal we changed class to HU but we’ll be benching ourselves against H1 times.

qualifying session – transponder wired.  start to push the car a little more gradually. 1:55.8x, still plenty left.  after the session Dan noticed the iVTEC wire was not functioning so power was down a bit.  now, gearing calculation shows 8500 in 4th gear on 235/40/17 = 110 mph.  i shifted at 8000 revs and the straights requires 5th gear.  however if I use more revs the car pretty much finishes on top of 4th @ 8500 on end of the straights.  we topped off the tank and after qualifying we weight in at 2441 lbs.

race session – since we were still establishing baselines we decided not to make any changes until we start pushing harder.  we didn’t make any changes after qualifying session, just check tire pressure and oil level and then wired iVTEC in.  but from the moment we fire up the engine to warm up for race, the engine sounded a little funny, i thought perhaps it was just the iVTEC…  warm up lap, the car was WAY down in power, and was misfiring a lot (good thing it wasn’t pinging; we ran 100 octane fuel).  the wideband voltage reads 1.10-1.15!  and 1.0 was suppose to be 14.7:1.  something was obviously wrong and i exit and drove into hot pits while others lined up for standing start.  Dan raises the fuel pressure and i go out behind everyone to turn in some laps.  it ran slightly better but was still quite lean and after 2 laps i just pulled off not wanting to damage the car.  we suspected the stock civic pump was going out.  we checked the plugs and sure enough they were white.

Sunday, Oct. 9th, 2005

We arrived 7am to put the fuel pump into the car.  It is a Walbro 255 LPH high pressure pump.  We also checked the injectors and fuel filter, both had tiny amount of debris in it but nothing serious…  Fire up the car and the car ran a little better but still lean.  So we bump up the fuel pressure from 42 (reading on MOTEC ADL) to 44 psi.  We also removed the rear wing to see how the car feels.

practice session – can ran kind of poor, still lean.  it was reading mostly around .95-1.0 occasionally to 1.05 and 1.10 but for the most part it sounded okay.  i stayed out because the motor had a hint of misfire but otherwise sounded okay.  i didn’t push hard and just go around for more practice and feel the car with out the rear wing.  2:00 flat laps.

qualifying session – we bump up the fuel pressure some more to 48 psi.  i go out and it was reading .95, not ideal yet.  the strange part is during the session, it would sometimes lean out, and comes back to .95.  it was quite puzzling.  i was able to get it down to 1:54.x about 3 seconds off current H1 lap record.  as you start to push the car towards the limits the car feels a little on the “soft” side; not super precise nor responsive.  brake pedal was mushy and not easy to modulate so i left a lot on the braking zones.  it just wasn’t confidence inspiring to go all out.  but we are happy with the lap times as not only the car isn’t at its best it is also on full thread tires.  i did push the car a lot more on this session as indicated by the tire pressure they warmed up to like 46 psi which is a bit high.  we bleed them down to 40 psi all around for race.  we up the rebound and compression 1 click all the way around to see if it would increase the sharpness/feel of the car.

race session – when Dan moved the car to check the MOTEC during the break he said it seems like the clutch is going out.  I was surprised because I had been babying the car all the with easy shifting.  But he theorizes because the clutch pack Mugen diff locks hard, and the engine is torquey it puts a lot of load on the clutch when coming out of the corner hard (which I started to do in the last qualifying session).  When I tried to start the car to warm it up the car moved a little even though I clutch in while the gear was in 1st.  Indeed the clutch was working sporadically now…  A very bad sign and we have to go to pre-grind in 5 mins and worse, we are doing a standing start.  During the warm up lap it shift okay…  you can feel the clutch not fully disengaged sometimes…  just have to deal with it.  At worst I will just keep it in 4th gear going around the whole track, assuming I can get the standing start to work.  To my relief the car made the standing start just fine, I was able to keep my position.  But on entry of T10 the car lost power completely (and that’s a good thing I mean that’s right before the track exit) and I just straight coasted to the exit and entered the hot pits…  turns out the accessory belt broke!  I didn’t complete 1 lap, that really sucked…  But oh well we have learned plenty and one more test day we should be able to iron these bugs out.

final thoughts – Overall the car is well built and pretty fast out of the box so we are happy being 3 sec. off H1 lap records.  This car has been on track less than 2.5 hours total since going K20A and still plenty of fine tuning on suspension on braking are needed.  We will diagnose the fuel problem on the dyno and try to resolve that.  We suspect it might be some sensors perhaps IAT, MAP, or TPS which might be out of calibration and causing the ECU to choose the wrong part of fuel map.  We need another test day or two to fine tune the car to make it easier to drive at the limit.  And then it will soon be a legitimate H1 contender!

Related articles

About GhettoRacer

racer, driver coach, taoist, yogi, dreamweaver, bballer, rebel, philosopher, entrepreneur, kiva, lonewolf, vagabond, photo/video shooter, storyteller
This entry was posted in Japan, JDM cars and culture, Retrospective, Transportation and tagged , , , , , , , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s