V8 Midget

After a few seasons in the F2 class and some good results, the team sat down and talked about our plans for the next season. The unanimous decision was that we had paid our dues and learnt a hell of a lot in the F2 class, and it was time to move up in engine power and race in the open grade. Obviously the costs and stakes go up with this move, so it was not a decision made lightly. But with anything, eventually you have to pull out the stops and see what you can make of things..

So the choice of engine had to be made, a vital factor in both the car performance and the budget required..

The main options are laid out in the Speedway NZ regulations, 166 cubic inch capacity for the pushrod OHV engines, down to 144 cubic inch for DOHC 4 valve per cyl engines. I’d sat down and done some calculations that said that (on paper) the advantage of the extra flow capacity of a modern 4 valve head and combustion chamber would outweigh the disadvantage of the smaller capacity limit. This limit would allow us a 20% increase in capacity for our Toyota 3SGE engine, unfortunately under investigation neither the block or cylinder head flow capacity would allow this increase.

The American 166 cubic inch engines are very expensive for a new engine, and the older engines, while still expensive are not competitive and becoming unreliable. We did not want to spend this money upfront and then have to spend more and more rebuilding engines during the season…

We looked at all options, including suitable automotive based 144 cubic inch (2400cc) engines that could be modified for racing purposes, however the demands are so different when compared to automotive requirements our search came up empty.

One day a brainwave struck. While the 4 cylinder 2400cc engines are not suitable, what about the motorcycle based alternatives? Obviously there are no relevant 2400cc motorcycles, but if we were to combine the essential parts of two 1200cc engines, then we would be heading in the right direction. We have no limitations on the number of cylinders allowed, and the modern motorcycle engine technology is fantastic, with high reliability and specific power levels approaching F1 levels from not too long ago. Besides which a 2400cc 32 valve V8 racing engine would sound pretty neat too.

The standout engine we picked was the Kawasaki ZX12R, the fastest, most powerful and fastest accelerating production motorcycle on the market. I had power and torque figures from a competive 166 cubic inch (2.8L) engine as a benchmark, and was able to find tested figures for the ZX12R. After performing calculations to enable a proper comparison of the 2 x ZX12R engine and the 166ci benchmark, it showed our engine concept would have both a power and torque advantage over the current front runners.

Now I sat down for a budget, obtaining prices for 2 used engines from Australia, and making estimates for design time and manufacturing time and cost for the custom crankcases and other parts required. Certainly not a cheap or easy exercise but one which was still cheaper than a new American engine, even including the one-off design cost!. By this stage the idea had taken hold and gathered momentum. I verified our engine layout with Speedway NZ to ensure it met the rules, and gained the OK some time later.

I have no doubt the timeline and budget will stretch out but have accounted for this to the best of my experience and we’ll see what happens with close monitoring.

I’ve bit the bullet and imported all the OEM engine parts required for the project, now its time to sit down at the computer and drawing board and get some design work done. This will be done with a close eye on the car installation, with positioning of ancillaries and weight distribution high on the list of prioritys. For the first iteration all of the mechanical components will be standard Kawasaki items. There is not a lot that can be improved already with these engines and they work well enough for the road bikes for Kawasaki to offer a warranty on… Not something you get with racing engines!

It must be pointed out that this idea is not a new one (as with many!), Ron Hoettells of Sesco has built motorcycle based Kawasaki and Suzuki V8 speedway race engines out of Wisconsin in the 80’s and 90’s, as has Western Springs promoter Bill Buckley who raced a self-built fearsome 1.5 litre V8 two stroke engine in the 80’s.

The development plan after the seasons racing and proving will be to produce other versions for the engine for use in speedway racing and also circuit racing / road performance cars. It will be unmatched in power to weight and size in these applications, with factory type reliability of main engine components. This will also help me recover the design and development costs. Interested parties please contact me.

Stay tuned for further updates. We need to be dyno testing in September to make our targets for car installation and first season practises in October, so its all on.First pictures of the solid model design work and engine configuration will be available soon.

This entry was posted on Tuesday, August 22nd, 2006 at 1:02 pm and is filed under V8 Midget. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.