RGB Racer

So I’ve made some thinking progress about the new chassis build, and been discussing it with Duncan and Tim.

We’re in agreement on the following.

1)  As this is the first time we’ve built a chassis, it is going to be hard enough without attempting a re design.  Don’t expend effort on flights of fancy that cost cash and waste time.  Transfer the known working kinematics and geometry “as is” where ever possible.

In other words  KEEP IT SIMPLE STUPID! KEEP FOCUSED!

2) To keep costs down, transfer all major components from the existing car.  BUT never bolt anything back on the car unless it is lighter than when it came off the old one.  Even if only by the weight of a washer.

That means track/width etc need to stay the same.

3) If a part is old/worn out out, has proven unreliable in the past change it.  That means I am allowed to refurb the steering rack, wheel  bearings and diff mount hardware.  Similarly we’ll be rebuilding wishbones with rod ends/spherical bearings.  I’m also  allowed to add lightness by replacing heavy steel parts with bling Aluminium ones.

4) Swap the engine to  a zx10. I’ve had a long chat with another RGB mate  Bob Mortimer over at www.furybusa.org.uk, who is content that his zx10 is powerful enough, and much cheaper than the Honda alternative.

5)  If we’re going to make next year’s Birkett then any bodywork changes are likely to have to come last and we’ll run next year with the existing bodywork.

So the plan is.

1)  Finish rebuilding my wife’s 1979 1275gt mini.

2) Measure the geometry of the old car, take careful notes.  Then strip clean, measure and store all the old kit.  Be very careful to weigh the car and components at every stage.  Keep Good records.

3) Dispose of those unwanted components to make space in the garage.

So Duncan and I are cracking on with the mini, and we’ve also obtained some decently accurate post scales for weighing stuff.

Lastly I’ve obtained a 2m x 1m industrial table made from 1.5″ box section to act as a build datum table for the  new chassis.

So some progress has been made… but physically it is currently mostly on the mini.

You’ll have observed that the site hasn’t been updated for more than a year.   This is because I haven’t been doing much in the racing world for a while, due to lack of cash, and knowing that you can’t actually afford to go racing is a great enthusiasm dampener.

However during this time the car has sat in the sat in the garage untouched and unloved, and suffered the indignity of being ignored and used to stack stuff on,  but she was ready… ready to flare into life and show her mettle again!

The chance came when I scraped the cash together to to go to the 2011 750 Motor Club Birkett with Tim, Dan, Derek and Doug and all my other RGB mates.   I love the Birkett, it is by far the best racing of the year, all the more enhanced by the team atmosphere and garage full of willing helpers.  It is a 6 hour team handicap endurance race and I had a fantastic time.    Unsurprisingly the smouldering embers of my passion for motor racing have flared into a full on conflagration again.

I had a great stint of 50 minutes with lap after lap of fighting with a very closely matched chap in a 750MC Kit Car racer.  We swapped places constantly, sometimes he was baulked by traffic, sometimes I was…. but the battle raged and places were continually swapped as we caught and passed what seemed like dozens of slower cars.   it was particularly memorable when we both swooped either side of a D type Jag in Maggots, and then immediately got on with the battle again on the other side…. Fantastic stuff. No quarter given… non asked  firm but fair racing with no contact whatsoever despite being inches part… fabulous.  Best of all I won in the end after he spun trying to close the gap on me for the nth time.

So what to do?    theres a glimmer that the financial constraints will ease in a year or so, but how to keep the flame alive until then?… both Dunc and I miss being in the garage.

Now my car is old,  it is also now uncompetitive, as with me in it is 60KG over the minimum weight limit…. that’s like driving around with a passenger sat next to you.  The newer generation class R cars are some 4 seconds down the road from me.   they also have some 10bhp more than me.   So old, worn out, heavy and slowish are my problems.

I’ve looked a getting a newer car, but to be honest there’s no way they are viable financially for me…. and anyway I’ve got a car that is now sorted and handles well,  I just need to add power, and in the words of Colin Chapman… Add lightness!

So to the plan.

For a while  now I’ve had this in my mind.

Excuse the poor quality scan.    It the MKII Genesis chassis, and is significantly lighter than mine, as you can see its main structural components are laser cut and CNC bent 3mm transverse steel bulkheads.    These are precut and contain all the holes for the front suspension mounts, steering gear, and the main front/rear chassis rails.   They are a very big step along the way towards a pre-jigged chassis, and certainly take a lot of the fabrication effort out of accurately making a new chassis, without Jigs.  They are at least a little self jigging.

I’ve had the main 3 front bulkheads for 3 years in the corner of the garage.  I may not be able to currently afford to race much.   But I can afford a few bits of tube to connect the bulkheads together and get this project underway.    Best of all the geometry and major component are the same, so I can transfer them over (with a bit of refurbishment along the way) to the new chassis.  Tim Pell simply took the design conclusions he had made when building/ modifying my Mk 1 chassis, and built the Mark 2 chassis to be significantly lighter.

This is born out by the fact that about 3 years ago RGB has a mass weigh in. My Genesis was the lightest mid engined car in the field at 502KG for the chassis. And the lightest Genesis in the field, by 15+ Kilos, but my engine is also lighter than the zx12 run by the other Genesis boys by at least 30Kilos…. so there are at least some 15Kg available to be pulled out of the chassis.

Incidentally the new generation of Mid Engined RGB cars (Sabre, Countour and spire) are all significantly lighter still and well under 500Kg

So my estimates of available weight to be lost are.

Chassis/Cage   15Kg

Airbox                  5Kg

Fuel System        3K

Uprights/Unsprung  8K  (2Kg per corner)

Coolant System    5K

Gurney flap         2K

Rear bodywork  5K   (mostly of filler)

Drivers spare tyre   10K

That’s 53Kg

Given the car is something like 515 KG now…. lets shoot for 460Kg…. with  me at 110Kg  (assuming I can lose my spare tyre) and we are close to the weight limit.

So lets state a public objective…. Re chassis the car, and be ready for next years Birkett.  

I’ve made a promise to my son to be there as he missed this years due to illness.

So watch this space for more news…. hopefully RGBRacer is resurrected!