Archetype's Pro7 Mazda RX-7 race car

[Archetype]

Hey fellas,

So I started a thread about my Series 1 RX-7 project back in August 2009 (viewtopic.php?f=17&t=19560), but there hasn't been much in the way of updates on it since January of this year.

The reason for this is I've been saving my funds for another project that I have been secretly working on. I thought I'd share it with you now that it's definitely going ahead and starting to take shape quite nicely.

Since I was an early teen (15+ years ago), one of my life goals has been to compete in a sanctioned race series. I've always been into RX-7s and had previously considered buying or building a Pro7 Series 1/2/3 car. However, I was put off by the fact that the cars are getting very long in the tooth now, with speed (compared to modern cars), reliability and parts becoming an ever increasing issue.

A few years ago, the 'Pro7 Plus' class was introduced to the Pro7 Racing Series, which allowed the later model FC and FD cars to compete. Now the original concept of the Pro7 Racing Series consisting of the Series 1/2/3 cars was to provide relatively cheap, competitive and fun racing for newcomers and those on a tight budget. Unfortunately the new Pro7 Plus cars cost a lot more to build, so all I could do was watch from the sidelines and hope that one day I was be in a financial position where I could get involved.

Going back around 18 months or so, I met a Pro7 member by the name of Graeme Hill, who told me about the possibility of yet another class being introduced to the Pro7 Series, which would sit somewhere between the original Pro7s and the Pro7 Plus cars. The new class would once again be based around the concept of cheap, competitive and fun racing for newcomers like me.

Over the next year and a half, Graeme kept me informed of any developments in regards to the new class, and I knew that this was going to be the ideal solution to help me reach my goal of competing in a sanctioned race series. In June of this year, I attended the North Island Mazda Rotary Racing Association AGM, where the final details of the new class were discussed and the 'Pro7 Production' class was officially confirmed.

By this stage I had already taken a punt and purchased a car, and I was now ready to build the car up to spec for the upcoming 2011/2012 race season.

To be continued...

[My name is Russell]

Looking forward to updates sounds good

[rot808]

so what are the rules surrounding this new class?

[anglia4]

Good stuff!

[Archetype]

so what are the rules surrounding this new class?

The technical regulations for the new class aren't on the Pro7 website yet, but the Pro7 regulations are:

http://www.mazdapro7racing.co.nz/uploads/90505/files/2010-11-Sch-RX-and-P7P.pdf

I've got a print out of the Pro7 Production regulations here and just comparing them quickly now, the main differences relate to the suspension and engine internals. It's basically a 'lite' version of the Pro7 Plus car. I guess the best way to summarise it is a lot of little things that are allowed in Pro7 Plus are excluded from Pro7 Production. All these little Pro7 Plus modifications and additions can make the cars quicker, but they add up to a reasonable amount of money too. I've been told that some Pro7 Plus cars have had up to $80,000 spent on them. My car should cost less than $20,000 all up. Obviously it won't be as competitive as the Pro7 Plus cars, but it won't be too far off.

[Truenotch]

It will be interesting to see how the new class goes. From what I've seen, the prototype production car wasn't particularly quick - often lapping amongst the series 1 cars.

I reckon you could build a Pro7 plus for 20k. There's not that much to them and shells are dirt cheap at the moment. A good engine would likely cost 7k or so, leaving 13k to buy a car (2-3k roller) and build it into a racer. Surely a cage, suspension, brakes and tyres wouldn't cost more than 10k to put together?

Good luck anyway, I'll be watching with interest.

[mikuni]

I reckon you could build a Pro7 plus for 20k. There's not that much to them and shells are dirt cheap at the moment. A good engine would likely cost 7k or so, leaving 13k to buy a car (2-3k roller) and build it into a racer. Surely a cage, suspension, brakes and tyres wouldn't cost more than 10k to put together?

Perhaps but to be competitive you're probably going to struggle against the guys with 4 times the budget.

Was Graham Hill already running a car built to this spec? I never understood why his FD was always running with the early cars.

[Archetype]

It will be interesting to see how the new class goes. From what I've seen, the prototype production car wasn't particularly quick - often lapping amongst the series 1 cars.

I reckon you could build a Pro7 plus for 20k. There's not that much to them and shells are dirt cheap at the moment. A good engine would likely cost 7k or so, leaving 13k to buy a car (2-3k roller) and build it into a racer. Surely a cage, suspension, brakes and tyres wouldn't cost more than 10k to put together?

Good luck anyway, I'll be watching with interest.

Yes, you are mostly right about the prototype car being amongst the Series 1 cars initially. Graeme's car has improved over time, and it's now sitting between the Series 1 and Pro7 Plus cars in terms of lap times. Going from what was discussed at the AGM, this is where it shall remain and also how the race starts will be managed. I've only done lapped times, dual sprints and track days, so being sandwiched between 2 classes of experienced drivers will be exciting/scary enough for me.

So far my build cost is $6,360.17, which includes the purchase of the car, the roll cage (not welded in yet), the C-West style front bumper and rear wing, plus a bunch of other little bits and pieces that I will cover in detail later.

[Archetype]

I reckon you could build a Pro7 plus for 20k. There's not that much to them and shells are dirt cheap at the moment. A good engine would likely cost 7k or so, leaving 13k to buy a car (2-3k roller) and build it into a racer. Surely a cage, suspension, brakes and tyres wouldn't cost more than 10k to put together?

Perhaps but to be competitive you're probably going to struggle against the guys with 4 times the budget.

Was Graham Hill already running a car built to this spec? I never understood why his FD was always running with the early cars.

Yes, you are right about trying to compete with the big budget cars - I'd have no chance. You are correct about Graham's car being prototype spec too. Here's an article that Graham wrote about his progress back in December 2010: http://www.irc.org.nz/news/future-car-for-pro-7

[SHGWAG]

So I'm guessing that you're using an FD Chassis?

If you're on Toyspeed, PM Emperor, as he has been racing a pro 7 FD for a few years now.

[Archetype]

Continuing on with the background story...

On a sunny Friday afternoon in February of this year, I drove from Hamilton to Auckland to check out a freshly imported vehicle which would be suitable for my race car project. A few weeks earlier, a vehicle importer and rotary enthusiast by the name of John Tucker had emailed these photos of a very tidy non-compliable 1992 Mazda RX-7.

I had a good look over the vehicle, took it for a test drive and decided that this was the right car for me.

[Archetype]

So I'm guessing that you're using an FD Chassis?

If you're on Toyspeed, PM Emperor, as he has been racing a pro 7 FD for a few years now.

Yup, that's right (see pics above). Do you know what Emperor's (real) first name is?

[SHGWAG]

Jason (Forget his last name).

Hamilton local

His dad also races

[Archetype]

Ah yes, most likely Jason Martin and Ian Martin. Not sure if I met them at the AGM or not.

[Truenotch]

^ That's the one.

After talking to Todd at PN Automotive today, he said their car that won the 2010/11 championship would have cost no more than $30k to put together... And that includes stripping the engine to replace the RX8 rotors with RX7 ones mid season because they thought the rules had changed. Turns out the rule change doesn't take place until the upcoming season.

Engine: 7k

Suspension: $1400 per corner ($5600 total).

20 would be cutting it fine though, and it makes sense to start off in the development series to build up car control & racecraft skills before going all out.

[Archetype]

Several weeks after viewing the RX-7 in person, the seller and I agreed on a very reasonable price. Once payment had been made, I arranged to have the vehicle brought back on a trailer with the help of Graeme Hill.

We headed back up to Auckland on another lovely sunny day and picked the car up.

Back in Hamilton, with the car safely tucked away in my warehouse. Now I had the chance to have another really good look over the car.

The car has only travelled 88,000km, and looks to have been maintained very well.

Both the interior and exterior are extremely tidy.

Other than a few little things here and there (such as the wheels and suspension), the car is basically standard as it left from the factory, right down to the unused space saver tyre.

Even the factory toolkit remains in place and looks to be unused. I feel a little guilty about using it as a race car, but it's nice to start with a tidy, solid foundation for a project.

The car arrived from Japan with this set of 17x9 Sparco wheels on it.

For race duties they'll be replaced with this set of factory 17x8" wheels from a later model Series 8 RX-7 that John kindly included in the sale.

These factory side skirts won't be required. I prefer the smooth clean lines of the RX-7 without any form of a bodykit where possible anyway.

Yes, the car is currently an automatic! Strangely I have owned a few automatic RX-7s (this is my third), but I've found that the automatic cars are generally in a far better condition to the manuals. Swapping over to a manual isn't much of an issue anyway.

And luckily this manual gearbox was included in the sale too.

Now the strip down and build up can begin.

If anyone is thinking about buying a non-compliant RX-7 to build a race car (or thinking about having a vehicle imported from Japan for that matter), I would highly recommend John Tucker. He's a rotary enthusiast and a hell of a nice guy, and will do his best to help you out. Just contact me, and I'll put you in touch with him.

[SHGWAG]

Are you going to strip the interior?

If so, I want your Parcel Tray!!!

Also, what else will you not be needing? I'm always on the lookout for spares.

Yea, it was Jason Martin who I was thinking of.

[Archetype]

Yep, the interior is stripped now, and I won't be needing much of it, including the parcel tray.

You can come over and have a look through my spare parts if you want.

[SHGWAG]

I'm keen.

Are you free Saturday?

[Archetype]

I might be heading down to Taupo to skydive and watch the dual sprints on Saturday, but it depends on the weather. Will let you know closer to the time?