The car is a 1978 Datsun 280Z Coupe. It has been modified in accordance with the SCCA Street Prepared rules. As with most enthusiast cars, this one is a work in progress. I will be updating this page as we update the car.
The suspension modifications start with Ground Control 2.5 inch coil over struts with Tokico Illumina adjustable inserts at all four corners. Current spring rates are 225lb/in in the front and 250lb/in in the rear. Camber/Caster plates and eccentric control arm bushings provide the fine camber and caster adjustability necessary. We are currently using a Ground Control adjustable front sway bar and a Ground Control non-adjustable rear sway bar. All the bushings have been replaced with urethane or other non-metal bushings.
An aluminum seat along with a four-point, cam-lock harness keeps the driver under control (well, the drivers body anyway!). A Personal brand Grinta steering wheel and a Momo shift knob on a shortened shifter shaft help the driver control the car.
The interior is mostly stock. The stock radio still works through speakers in the stock locations. I have replaced the carpeting on the transmission tunnel with the diamond vinyl from earlier cars. (I think I'm one of the few who actually like that stuff!) I have also replaced the stock headliner with a thinner material (for more headroom!) I had custom carpets made to replace all the floor and sill coverings. The rear carpet is stock without luggage strap holes (luggage during an autocross is generally frowned upon) The seats have been lowered and replaced, with an aluminum racing seat for the driver and a lightweight fiberglass seat for the passenger. Both have 4-point harnesses to keep driver and passenger snug in their places. There is even a stock Japanese Z clock with date and minute hand that works quite well. Kind of odd driving a Z with a working clock!
Street Prepared rules require that the long block remains stock, but Intake and Exhaust are free. We are using a rebuilt N42 head with a ported stock intake manifold. A TWM big bore throttle body is also helps open things up. The header is a non-descript unit with small primaries and a 2.5 inch exhaust pipe with two mufflers. This will eventually be replaced with my EMI Racing header which worked so well on the Wonder Car. We will also be adding a custom fuel rail to ensure good fuel flow. The ignition is stock for now. We will eventually go to an aftermarket electronic ignition system, hopefully one with a rev-limiter! Right now the drivers conscience is the rev limiter. Not a reliable device!
The stock 5-speed transmission is backed up by an R200 clutch-type LSD (limited slip differential) with a 3.54:1 ratio. We use RedLine fluids in the engine, tranny and diff and have had excellent results.
A balanced driveshaft with new U-joints was recently installed. The idea was to tame an odd vibration we were having. It didn't help!
A R180 differential with either a clutch-type LS or a Quaiffe LS is in the future.
If you have driven an early Z (70-78) you know the brakes are barely up to the task for street driving, for autocross they really suck! We replaced the rear drums with some Brembo units I had stored in my garage. The brake pedal on this car is lower than on other Zs I've had and raced so we are working to remedy that. We will be doing a complete overhaul of the braking system in the early summer of '99. Hopefully we will maximize the braking potential while still remaining legal for our racing class. We are currently running Porterfield metallic pads in front which did really well on the Wonder Car, but they aren't helping on this one! I'll update this when we do the work.
Update 8/99 - Well, we did the brake job. Replaced the master cylinder, both rear wheel cylinders, front calipers, front rotors and Porterfield Carbon Kevlar shoes and pads all around. The verdict is....the brakes still suck! Everything looks really nice, and they work better than before, but still not on a par with the Wonder Car. One interesting fact I discovered is that California cars (of which this is one) have some different brake parts. The CA cars have some sort of proportioning valve to help avoid locking up the rear brakes (or some such!). We are going to investigate replacing the lines and removing this thing to see if that improves things any. Stay tuned....
Wheels and Tires
We are currently using Kumho VictoRacer V700 225-50-15 tires. We have been using these for over three years with good results. They grip well, are fairly forgiving at the limit and are very durable. With two drivers running more than 10 events, driving schools and other events throughout the year we have only needed one set of tires per year. We use a variety of wheels in either 15x7 or 15x8 sizes.
We currently run 15x7 Panasport Ultralights, 15x7 Enkei aluminum mesh (actually lighter than the Panasports) and 15x8 Revolution 5-spokes. I bought the Revolutions with the idea of running them as our race wheel, but they turned out to be so heavy we use them with street tires. They look nice and I get lots of compliments on them, but they must be made of depleted uranium or something.
This is one area where we definitely need to improve. The fenders need to be flared and we need to use larger 15 or 16 in wheels and tires.
You have probably noticed from the photos that this car doesn't look exactly like a '78 Z. The bumpers have been replaced with those from a '74 260Z. This was done by the previous owner. I really prefer the skinny bumpers. It does confuse people though, because I have also removed most of the exterior badging. This car also has a roll bar that was installed by the previous owner. Hopefully we will get a camera mount soon so we can get some video captures for this site. (oooh, I can almost taste the wasted bandwidth already!)
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