The Shopping List

Below I will go through what we got for it and why, we decided early on to make this engine reliable. There are a lot of potential issues which we wanted to address once and properly.

Kevin has been involved in professional motorsport for many years and has seen shortcuts end badly, so taking the time to think it through carefully will hopefully mean no nasty surprises:

Engine – We did not only look at Suzuki’s, the Kawasaki ZX14 engine is more powerful and is better suited to a car because of a few design feature such as a much larger clutch. But they are not as available as the Hayabusa, and the amount of parts and knowledge around for the Hayabusa is huge, so we quickly dismissed the Kawasaki as a viable option. So, as I said before we bought the gen 2 Hayabusa, a 2011 with only 3000 miles on it, so pretty much brand new. The guy we got it from was wrecking the entire bike. So we got in contact and made sure he gave us all the bits it needed to run. So we had a complete engine, from air box to extractors. We also bought the fuel pump and dash off him and got him to send the loom to another guy in the USA for a mod (see below).  Why the fuel pump and the dash? Well the fuel pump is going to be the correct pressure, it is as simple as plug and go, hopefully. The dash because again it is plug and go, it also has gear display and shift light, and reads up to 280kph which should be handy. Although I am not yet sure what is involved to get the speedo going.

Loom – As I said we got the loom sent off to Downs Engineering. Mike Downs specialises in making Hayabusa’s fly. So we got him to strip out the loom of all the unnecessary stuff like indicators etc, and to remove all the alarm sensors such as roll over sensor and kickstand alarm which will kill the engine. We also got him to lengthen the dash cluster wires and change out the key with a switch and ignition button. For the price it would not be worth even attempting yourself.

www.downsengineering.com

Dry Sump –  The problem with a bike engine in a car is oil surge. A bike never experiences it because in a corner the bike leans over and the oil sit in the pan, just like swinging a bucket of water upside down, no problem. So in a bike there is no need to baffle it or even think about oil surge. Put it in a car that experiences any hard sort of lateral G’s and the oil has the potential to disappear out of the sump, if it does goodbye engine!! There are a few solutions out there from gated sumps to swinging oil pick ups, but the ultimate solution is to dry sump it. It is not cheap but beats the hell out of picking up the engine internals off the road, and then buying a new engine, and then dry sumping it.

There are plenty of options out there for dry sumps, most use the water pump drive to run a small scavenge pump. The are other more expensive systems that have remote belt driven pumps but they are getting towards the cost of another engine. So after a lot of looking at a few we decided on one from SBD in the UK, we liked how they have used solid tubes instead of hoses. Every hose means another fitting that has the potential to fall off, and by the time you price the aeroquip hoses and dash fitting the additional cost of the SBD unit is justified.

Plus a dry sump has a much lower profile than a wet sump so should help with clearance in the car.

www.sbdev.co.uk

Dry Sump Tank – Now you are sucking all the oil out of the engine, you need to put it somewhere, but not all tanks are created equal. Anyone who knows about dry sumps and scavenge pumps know that oil aeration is a big problem. The scavenge pump sucks anything, so ends up pumping a lot of air, you need to get this air out before pumping it back into the engine. Again Mike Downs had the solution, a tank made by Aviaid. They are made to order with the dash fittings you require. Other tanks just have push on fittings, but if one comes off the engine finds it hard to suck the oil off the ground.

Electric Water Pump – Now the scavenge pump is where the water pump was you have to install an electric one. Davies Craig in Australia make a reliable unit that are readily available.

Reversing Box – Motorbikes don’t go backwards, and unless you want to do like the Flinstons and push, a reversing gearbox is a necessity. Plus to race it or put it on the road it has to have reverse.

Again a couple of options, a purpose built gearbox or strip out a regular gear box and put it in 4th (1:1 ratio) and use reverse when you need it. The second option has been used very successfully and some guys have actually got rid of the reversing box and gone with the standard box. We found a reversing box out of the USA that no one here has used, it has turbo 400 splines at either end and it was built for use in sand rails (USA dune buggies) and should be good for 500hp. Guys here in NZ have only used the Quaife box, and had a few problems. Hopefully our USA one will work better, time will tell.

www.roadstercycle.com

Drive Shaft Universals – A known issue with putting this engine in is the angle of the first drive shaft out of the engine to the reversing box.

Due to the chain drive on a bike being at the rear of the engine, when you turn it 90 degrees to drive a RWD car the output shaft ends up a long way to the right.

The usual way to deal with it is to put a typical drive shaft universal on. Talking to some driveshaft specialists they say that a universals max angle is 3 degrees. Our calculations are that it will have 7-8 degrees or more. The problem with a universal, it is pinned and the moving part swings from there, so it has to swing a long way and then back in one revolution. The more angle, the more swing, the more vibration, and at high revs it can’t last for ever, and the last thing you want is that to come loose by your feet.

Our solution is to do what BMW and Mitsi EVO use, a CV joint. Not quite like a wheel CV but the same principal, sliding bearings. Instead of a swinging motion it has a swiping motion but the key is that all spinning masses remain in one plane. So the theory is that it should not vibrate. The problem is that 7-8 degrees is still more than ideal for a CV driveshaft, but is best solution we have.

Engine Valves – The gen 2 engine has titanium valves, which should be better that the steel ones but the have been known to drop valve heads, ask Brad Mcfarlane. So some stainless valves to go in it as well, plus upgrade to competition valve springs while we are at it as well.

Con Rods – By all accounts the standard rods are fine and they rarely fail, in a bike. The thing is on a bike if you were to use full revs for more than a few seconds you it wouldn’t be long before you would need some clean pants. So the engine does not spend much time at high revs. But in a race car we are going to ring its neck and it will be over 8000rpm for most of its life and the first thing to fatigue and fly out of an engine are the rods. So Mike Downs again (this guy got a few bucks out of us) supplied us with some Wossner rods, currently the strongest Hayabusa rod available. 

Clutch – There is always going to be a problem trying to get something with 3 times the weight moving with the standard clutch. A bike will either wheel stand or wheel spin, a car with a whole lot more weight and tyre on the ground will not and the little bike clutch gets a real hard time. For those who don’t know, a bike clutch has a series of plates inside a basket. That basket has little fingers that stick out which the plates drive off. Well those little cast aluminium fingers are the first thing to go when the clutch can’t take anymore. Then those broken little fingers can go out through the case and because they are in the same case as the engine, they will spread themselves through the engine and most likely destroy it.

Most guys either takes it real easy on the clutch, or hope that it will last. As we do a lot of hill climbs and a good start is key to a good time, which means the clutch does a lot of work.

So the answer come in the way of a billet aluminium clutch basket and hub from Hays Machine Works. These guys are at the front when it comes to drag bike clutches. The clutch basket is rated for 1000hp, that should be enough.

A big thanks to these guys for sending us out a clutch basket. Usually you send them the one out of your engine and they modify it, but we didn’t have an engine. So they gave us one of theirs in good faith that we would send them our standard one once we got it.

Standard Clutch Basket

Billet Clutch Basket

Diff Ratio – The bike engine reduces the crankshaft revs into the gearbox by about 1.6. So by the time you go through our 4.77 diff ratio you will only do 130kph in 6th gear at 11,000rpm.

In the USA the have a race car class similar to Star Cars called US Legends, anyway they have a range of gear ratios for a 6.7” Toyota for only US$250, so a 3.44 ratio was ordered.

Power Commander – A common piggy back fuel only ECU system was also bought. This gives you the ability to change the air fuel ration as the standard ECU can run a bit lean when you modify the extractors. The last thing we is need detonation so we will dial that out on the dyno once we get there.

Cometic Head Gasket – Anyone who has built high performance engines will know about Cometic. They produce high quality multi layer steel head gaskets. Install one and never think about it again.

 

So a few things coming from the USA and after all that it will make no more power or do much of anything different, but it is all about reliability. When you are at an event and something goes wrong you would be wishing you had spent that $500.