Y66P GD3 Honda Jazz/Fit

Would you rather drive a fast car slow, or a slow car fast? Brett opted for the latter, and ended up developing that slow car so much, that it became a fast car.

Words and images by Brett Swain
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When i got this humble Honda Jazz, I hadn’t planned to do much to it, aside lowering it with some cool wheels and attend bulk track days.

It was 2021 when we finally moved out of our inner city apartment with a single car space, and I could once again have a second car to myself. My wife no longer needed to worry whether I would call her from the track to let her know I have totalled our family car, her Mazda 2.

I had never had too much of an interest in Jazz’s, but I’d seen some cool examples locally and in Japan, so a Jazz was on my shortlist alongside Accord Euros. But after test driving a mates GD Jazz, I was well and truly hooked. 

I was set on a yellow one, specifically the ‘Y66P’ colour code which Honda calls Helios Yellow.  Funnily enough, it took a while to track down one with the 1.5L “big block” and manual transmission, but eventually I found one through the help of my friends. No test drive was had, so I paid a small fee and took it away then and there.

It was fairly run down, having sat on a farm for a while, but I set to work doing basic maintenance and entering any track event that I had the time/money for.

It wasn’t long before the scope creep took hold. My good friend Grant from Honed Developments suggested I bring the car in so he could develop a brake booster delete kit, which would help me modulate the sensitive braking system that was more targeted towards senior citizens.

What follows below is a rough timeline of events of how we got to where we are today:

The night i picked it up. I stopped at a car wash on the way home to install the hubcaps that were in the boot.

The state of the brake reservoir on the first flush

Broadford track day

I started off with basic engine mods.

Weight reduction: Sound deadening removal along with A/C Delete.

Honed Developments brake booster delete. This could be the single best thing that was done to the car for track driving.

Installed a 4-point half cage along with a Y66P paint-matched Velo racing seat to help keep me planted through the corners.

Winton Raceway.

Fixing the bus-like seating position with custom Honed Developments seat brackets.

Production seat brackets installed.

Calder Park Raceway.

I was getting a bit annoyed with the round shifter hole, so I designed and sold some shifter plates that better suited the Hybrid shifter setup.

BC Racing remote damper adjusters peeking through the interior plastics.

Sale Sprints, looking and feeling more and more at home on the track.

Left: 320mm standard Momo Monte Carlo
Right: Custom re-trimmed 350mm version

Winton again.

Mfactory 4.9 final drive, Jun Flywheel and Exedy clutch install. This was a very late night.

Time to get serious with engine management. Haltech Elite 1000 install.

Honed Developments strut top kit.

Sandown track day.

After some sketchy return-drives in the rain after track days, I opted for a 2-tyre strategy, picking up some Konigs and Shibawheels to go alongside my TC-05s.

GoPro mounted to the roll cage, with a Rode microphone mounted in the boot to capture exhaust audio.

Back at Winton.

Brake upgrade courtesy of some Integra Type R components, paired with extended studs and PMU Club Racer pads.

I decided the front of the car needed something to match the profile of the side skirts, so found a DOOV lip from Yahoo Japan Auctions and had it imported, then painted and fitted.

After installing a set of CBR600 ITB’s and a Cat Cam, the engine (that had seen over 180,000km and 20 track days) finally gave up. We picked up a donor engine and Grant from Honed set about refreshing it, installing new high compression pistons, thicker rods etc. as well reinstalling the cam/springs/ITB setup from the original engine.

The new setup was dyno’d, making 85kw, which might not sound like much, but it equates to a 40% increase over the stock engine. It drives like a normal Jazz around town (minus the chop).

And this brings us up to where we are at now.

Future plans? Continue attending as many track events as possible.

Special thanks:
Grant @ Honed Developments
Shane @ CMS Performance
Michael @ Autosphere

Build Specs:

Engine
Mugen Muffler
A/C delete
Mugen oil cap
js racing radiator cap
Spoon drain plug
Honed underdrive pulley water pump
Honed lightweight alternator pulley
Honed EGR delete
Haltech Elite 1000 ECU
4-2-1 exhaust manifold 
Stainless 2” B pipe
Haltech wideband WB1
CBR600 F4i ITB’s
ITB Airbox
Cat Cam Sport 2503003
BC valve springs 
Aftermarket Rods
Modified GK pistons
ARP studs
Honed sump baffle

Drivetrain
Mfactory 4.9 final drive
Jun light flywheel 4.2kg
Exedy OEM Clutch
Hybrid racing shifter bushings
Hybrid racing detent springs
Mtec shifter selector spring
Honed CDV delete
Js racing trans drain plug

Exterior
Mugen grill
Modulo spoiler
DOOV front lip
VTIS side skirts
JDM headlights
Rain visors
Honed rear tow hook
Early tail lights
Rolled + pumped front guards
Rear wiper delete

Suspension
BC DS f6K r8k
Helper springs
BC endlinks
Ultra racing rear swaybar
Honed strut top kit
Honed rear shims
Nolathane camber bolts
Superpro control arms

Brakes
Honed brake booster delete
Honda ITR calipers
Honed caliper adapter
Peugeot discs
Project Mu club racer pads
Stainless lines

Wheels

Street
Front 15×8 +25 Konig countergram 
Rear 15 x 6.5 +38 Weds TC05
Advan V701 205/50R15 & 195/50R15

Track
Front 15×8 +25 Shibawheel G23
Rear 15 x 6.5 +38 Weds TC05
Nankang CRS 225/45R15 & 195/50R15 
Nutya short wheel nuts
Hardrace extended studs
Honed 3mm spacers F+R

Interior
4 point halfcage
Velo 6 point harness
Velo GP90XL Seat
Honed Prototype seat bracket
Hybrid V3 shifter 
Works bell rapfix 2 quick release
Honed shift knob
Honed fire mount
Honed pedals
Fire extinguisher
Android head unit
Swain Sports shift plate
Momo Monte Carlo 320mm
HKB EK boss kit
Daikei horn plate
30mm Hub spacer
Honed Prototype cluster hood
Indicator spacer
Sound deadening delete
Haltech OBD2 to CAN adapter
Mugen mirror cover
Engine Hour meter

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