SOLD!!

Datsun 1200 Coupe

Specifications

The following updates are in order from newest to oldest, and include some articles I wrote for a local Car Club Magazine. For further images see the Photo Gallery.

The Final - UPDATED 19 JANUARY 2001

My baby is now sold, and moved to Auckland New Zealand, where it will be entered in club events and possibly the Targa New Zealand. My new project is well underway which is a kit car called the Saker built here in New Zealand. I have installed a Toyota Quadcam V8 with Renault 5 Speed transaxle. The car will be extremely light around 1000kg, and have about 300hp. Watch MATT'S AUTOMOBILES webpage shortly for some photos and info. In the meantime, check out "The Saker Website in NZ"

Part 9 - UPDATED 01 AUGUST 2000

The suspension changes made a huge difference to the handling and definately reducing understeer (now down to 1:28s flat). However, regretfully, I must now offer the car for sale due to another project I have started. Watch Matts Cars homepage for an update soon. If you are interested in the car and live in NZ, drop me an email, you can also see if racing this Saturday (5th August) at Manfeild.

Part 8 - UPDATED 01 MAY 2000

Boy, things have changed a bit since I last updated this. After the Taupo meeting we found the car needed more negative camber at the front. I picked up some second hand adjustable camber plates off a GTiR Pulsar just so I could use the bearing plate.

My brother machined new camber plates themselves to suit the Datsun towers. To enable further adjustment however the old springs had to go. These made way to race springs of 280lb rating. Also fitted were Potenza adjustable motorkhana spec shocks from a late model Jap MR2.

I also in the process extended the front spoiler which now has a splitter on the front. The sills are now painted black ready for some more advertising. Last year the quickest time round Manfield for the Datsun with the h/performance road tyres was 1.33; now with better tyres and more negative camber, we are down to 1.30 flat. All for $500 dollars + tyres. Next mods are to reset the rear leaf springs and remove the spacers, improve brakes and change diff ratio.

Part 7 - UPDATED 04 JANUARY 2000

Another six months go by without an update so here goes. The Winter Intermarque series went well and I improved my lap times by 4 - 5 secs over the 6 meetings. I had basically reached the limit of adhesion with the road tyres so have now fitted road/race tyres. These are Yokohama Advan A032R, which work well in dry or wet. They have a full tread depth in a V pattern and although I have only tried them in the dry I am sure they will work wonders in the wet. Between Christmas and New Year I got the opportunity to practice with my car around the Taupo Race Track. This is a really fun challenging circuit and because it is short(I was lapping in 51 seconds) keeps you on your toes the whole time. I thoroughly enjoyed it, scrubbing in the new tyres in the process with more to come. The gearbox bearings and synchro between 2nd and 3rd are on there way out, but I have another 5Spd ready to bolt in. I am also still trying to improve the brakes and may fit a sprinter rear end (discs and LSD) before the start of the Winter series again.

Part 6 - UPDATED 26 APRIL 1999

Been almost 8 months since I last updated this, so thought I better let you know how it is going. Over heating problems continued even after getting the radiator recored, however that seemed to help. We believe after testing the radiator we had a blown head gasket. Removing the head we found traces of the gasket parting between the water jacket and combustion chamber, so it was replaced. Worst of all though, we discovered that the valves had been hitting the pistons, ahhhh!, though the valves or stems were not damaged is a miracle, we have now machined reliefs into the pistons for the valves - remembering I am still running dished pistons at present. We have just installed a Nissan Sunny 5 Speed gearbox as on the track we were running out of revs in top well before the braking areas on the straights. We calculated max speed on one particular straight in top to be 170km/h. I could have changed the diff ratio back to 3.9:1 or lower but it would be less usable on the street circuits. Hopefully the 5 Spd will gain us 2-3 secs on the track. The brakes we are still tinkering with, we have just removed the rear bias as the spring tension in the bias has been giving a spongy pedal feel. This Saturday we are back up to Manfield for the start of the Intermarque Series which runs throughout Winter.

Part 5

After the car was completed and run in, we took it to Manfeild to test it, and to find out what modifications needed doing to the car. Firstly was the cooling side of things. Before going to Manfeild we had suspected that the radiator was blocked, as it would get hot just from driving up and down the road. And as expected on the racetrack, after three laps the temperature gauge was over 220°F (about 95°C) and the overflow bottle was fulling up. We have had the radiator recored since with an extra row added and the temperature hardly goes over 160°F (75°C) with testing up and down the road. We also fitted an extra shroud between the fan and radiator so the air was better directed.

We are currently working on problems we have with the brakes, mainly a spongy pedal and reduced pressure, and it is hard to lock the brakes up. The main cause we think is the master cylinder being too small for the larger brakes installed. And thanks to Nissans interchangeable parts, we should be able to bolt on a bigger Sunny or 180B master cylinder. Other than that the car handled well and never missed a beat. It was also the first outing for the car with its new vivid graphics, which made it stand out. These were all done on computer before being cut out from special vinyl and stuck onto the car.

The car had its first dyno tune about six weeks ago (before Manfeild) and considering the block is standard, the 1390cc engine still managed to produce over 101hp at the rear wheels, which equates to approx 130 flywheel horsepower. This was measured at 6600rpm where they stopped taking measurements and was the not near the maximum power output for the engines setup (3500 - 7500rpm), so who knows what it is! The rollcage has been homologated and the car scrutineered and we only have minor things to sort out before its next event, which could be in the next two months or so.

Part 4

Through the winter months we had only managed to work on it on Saturday afternoon's when there is plenty of light and it is reasonably warm. After spending many hours preparing the body and fixing panels, before winter set in we had the final paint job applied which is called 'Marble White', on both the inside and outside. A front and rear spoiler were also sourced and modified to fit before being painted.

In the last part I mentioned about wishing to fit Wilwood calipers and rotors to the front. Well we went down the track of measuring and costing the brakes to fit the front, but it was almost impossible to find any rotor of a larger size to fit under the 13" Wheel with the Wilwood Caliper. The reason for changing the brakes now rather than when it was completed is the back face of the front wheels touched the standard Datsun rotor, so spaces would have been needed and the grinded would have to be used on the rotor.

After hunting around we found a pair of replacement struts off an 1981/1982 Bluebird ZXE. The discs are vented 10" with larger caliper and pad area. The money I had spent of the standard Datsun struts up until now was down the drain as I now had to get the Bluebird struts modified to fit. To do this the bottom spring holder was removed from the Bluebird leg and a threaded tube welding in its place. Then the bottom spring holder was cut from the original leg and attached to a nut which fits onto the thread. This allows the height to be adjusted without cutting any more off the springs. The original top mount and shortened King Springs were put back in place, as was the KYB insert. Datsun Sunny bottom arms were then used as well as the steering arm and stabiliser bar, to mount everything back in place. The bottom holes were slotted in the cross member allowing for camber adjustment later.

Once the front suspension was completed it started to come together a lot quicker including the installation of the motor and box, along with the radiator, windscreens and aluminium panel work. Brake lines were installed as was the petrol tank and fuel lines. Installed in the cockpit next to the drivers seat are both a brake bias valve and fuel cutoff switch. Seat brackets were fabricated to allow for easier adjustment of the seat for short and tall people. We purchased a Coby muffler and finished making the exhaust which finishes just before diff

The car is not too far off completion and it is really only the small things to finish off like the wiring, dash etc. Gauges have been purchased and include a 5" Rev counter with a programmable shift light. The wiring will be kept simple as it is not going to be road legal.

Part 3

I had started work on preparing the doors, bonnet, front mudguards/flares so they could be mounted back on the car. Front doors were lightened with all winding mechanisms removed and also the metal inside panel. Bonnet pins have been fitted and the bonnet adjusted to line up properly. I am hoping to find a suitable front spoiler within the next few weeks so that can be installed and modified to fit. The front valance as seen in the picture has been bolted in place instead of welded to allow for easy repairs later on if needed.

The motor is coming along well. Normally the Datsun runs the standard 1171cc A12 pushrod motor, but in efforts to get more torque from less modifications I managed to source a 1390cc A14 motor from a later model Sunny Coupe. Before Christmas I paid a visit to Camshaft Services in Palmerston North, where I discovered the head from the sourced motor was not worthy of the stresses placed on a racing engine. Brendon from CSL provided me with a fully rebuilt/reconditioned head as the basis to the modifications. The inlet ports were extensively modified including enlarging to fit the manifold and also removal of the pretuding valve guides in the port. See the difference below for the A14 head to my modified GX head.

Exhaust ports were also opened up and deburred of any unwanted material, the head was also planed to increase the comp. ratio. Standard Valve springs were tossed in favour of Triple valve springs, the third acting purely as a dampening device. The "GX" head as it is called also runs bigger inlet valves than the standard head. The completed head was then placed on a computerised flow bench where it was flow tested to enable the ideal camshaft to be ground. The flywheel was also lightened and the cam followers re-machined. At the end a computer report was printed, which references the camshaft to rev limits, power band and timings. With the power band being around 3500 - 7500rpm, it is in a very sedate mode at the moment.

The block remains basically in standard form with new seals, bearings, gaskets, rings, frost plugs and paint job. Motivating the modified head along are twin 40mm Dellortoes which, when fitted, will be drinking 100+ Octane Avgas. The standard 4 Speed Gearbox remains with a modified clutch manufactured by Vortex Clutches. With ratios in mind, it should be well geared for short sprints and power out of corners, but not top end speed.

To date I have purchased about 75% of what is needed to complete the car, including a Racetech Seat, 4 point Full Harness belts, brake bias valve, brake lines, battery box, kill switch, jockey wheel for the Trailer, a spare Coupe for parts, and a Datsun Roadstar Ute for support vehicle. It does tally up to be quite an expensive project (about $7000 on the car to date), however it has been more enjoyable than buying a completed car.

Part 2

After the car was stripped, I tipped it on its side and waterblasted the floor pan and then painted it using Hammerite Silver Grey after repairing the rust areas. The Hammerite gives it a great effect and makes it easier to keep clean and maintain.

During this time I had also sourced a Datsun Roadstar rear end, which has a 4.11:1 ratio compared with the standard 1200 3.9:1. Also it is alot stronger, has bigger axles and brakes. I rebuilt the diff and brakes assemblies, then cleaned up the rear springs fitting the mounting points with Nolathene bushes. We also put the wheels on at this stage to check for clearances etc.

With the rear suspension installed back into the car we started on some of the body work (and believe me, there is a lot of work needed here). By the previous owner the car had two very large crashes, one which total the front left inner guard and had a new one welded in, and the other on the back right corner which punched the guard in right on the corner destroying the line of the body. With a lot of bondy and panel beating we got the shape back. The rear flares were mounted up to check the clearances around the now fitted wheels, and to check the track width. To help the strenghten the car, I decided on on continuing the rollcage through to the front struts and placing a cross bar between the bottom of the two front roll bar mounts, about where the dashboard would normally sit. These were mig welded in place as you can see in the below picture.

Over the next few months I spent most of the time working on rebuilding the front suspension as well as cleaning out the engine bay. I had also purchase a second Datsun Coupe to use as spares (see the Photo Gallery), it now resides in the garage at home and is a great donor vehicle. The first item to be pulled off was the front of the car, the part that holds the headlights, radiator etc as the one on the race car had been cut off which may have also weakened the cars structure. We grafted this onto the car then undercoated the engine bay. Marble White was chosen as the finish colour, so we painted the engine bay so I could finish putting the suspension back in when it was completed.

The front struts were delivered to Total Performance in Lower Hutt where Ron shortened the top end of the housings(to give more travel with the lowered suspension) and fitted VW Golf KYB Sport inserts, and Mitsi V3000 rear springs shortened to fit into the required height. At this stage I was using the standard 1200 struts & brakes as you can see in the photo.

To finish the suspension off I painted or polished every item, reassembled with new Nolathene bushes and rubber boots. I had planned on fitting the car up with Wilwood Calipers and Rotors down the track but could not get anything decent to fit under the 13" wheel. Under the guards were painted with underseal and repaired where necessary.

Part 1

Back in April of 1996, a Datsun 1200 Coupe rolling chassis was up for sale in the Trade & Exchange, it had been raced previously and was fitted with a six point roll-cage and some lightened body work. It must have been more of an impulse buy as I viewed the car in the dark and when I went to pick it up it was dark, so it wasn't unitl the next morning that I saw what I had ended up with!!

Ahh, and as you can see by the photo, it looks pretty hideous and run down. Closer inspection shows what any 25 year old car would be like, rust and some wrinkles in the body work. There isn't too much to it, I mean the only thing inside the car is the steering column, and a radiator strapped with wire in the front (the front had been removed for some reason).

At this stage I had not planned what to do with it, so it just sat grazing on the lawn for a few months. When I started work on it, I finished stripping it down completely including glass, suspension, doors and mudguards before trailering it down to my fathers workshop.

 From this point we had made a decision to build it purely for racing so we could make it as light as possible and we weren't limited to what modifications we could make to it. When completed we are going to use it for Club Racing, street sprints, hill climbs and circuit racing.

For more information, suggestions or help, email me at mxz@gen-i.co.nz

For more info's on Datsun's visit "Martin Pot's Datsun 1200 Modifications" Page