Hayabusa High Output Stator & Regulator

Ordered a high output stator rebuild and rectifier / regulator from Rick's Motorsport Electrics in the US, also ordered a cable repair kit to replace the melted connector on my loom. This solution should provide a high enough output to correctly support the engine in the car application with twin pumps etc. I went with this option as the alternator setup was far more expensive.

The Rectifier-Regulator is designed with Mosfet Technology which makes the regulator run a lot cooler, it also has a higher output than standard and runs up to 40 amps.

I also sent my stator core back for rebuild and rewind. The stator has now been upgraded to provide an output of 500 watts compared to the standard 400 watts. The coil has been fully re wired and all connectors replaced.

I have fitted the regulator and also replaced the damaged connectors in the loom, will install the stator when I change the oil next and remove the dry sump tank.

Uprated Starter Motor & gear

The uprated starter and gear arrived, the version I ordered is a high torque and high output starter motor designed to overcome the Hayabusa starting issues. It also comes with a heavy duty gear to replace the stock item. The new gear is twice the thickness of the standard Suzuki version. 

As my original starter was from a 99-01 engine, I needed to fit a later starter cover and shaft to accommodate the new larger starter gear. On the later engines this was modified to fit a different gear that was made of 3 plates. The Brise unit is much more sturdy than either of the standard versions so should work well even when the engine is hot. 

Running In Rebuilt Engine

Have now completed three sets of 10 powerseat runs where I snap on the throttle in 6th gear at 3000rpm and hold it until 6000rpm. Really enjoyed driving the car so far, however I'm still getting used to the clutch when pulling off from standstill.

Found a few things that I need to look at:

When the engine is hot, the starter struggles to turn over the engine. When I let it cool it cranks fine. The issue is due to the high compression pistons now sealing a lot better. Have done some research and it seems to be a common problem. Fixes are either a different set of starter gears with different ratios, billet strengthened starter casings / gears and finally a choice of a more powerful starter motor or a 24v starter system. 

The brakes are getting a lot better and are quite progressive, need to check the balance adjuster settings.

I still think that there is an issue with the charging system. I found that when I went out the battery voltage was at 14.9v and when I came home later it was down to 12.5v, however did start the car a couple of times while the engine was warm. May be that the starter motor using a lot of current and draining the battery. 

The electrical system may also be loaded quite heavily, I have two fuel pumps, ecu, dash, can module, electric water pump, radiator fan etc etc. I will look at this and calculate if the standard 400watt stator is up to the job.

The induction noise from the foam filter is really fantastic and adds to the experience, only problem is it's too loud for track day use. Will look at getting a pipercross ducted airbox like the one fitted to Leon's car. This should quieten things down to a more acceptable level.  

Daytuner Dyno Results

Damian sent over a copy of the Dyno plot from his mapping session yesterday. The output of the mapping session gave 171 wheel hp and 99 ft/lb torque, this seems ok but is slightly less than expected.

In talking to Damian there are a few issues with the engine, the problem with the rings letting by is causing a loss of power and control of combustion at the top end of the rev range. I'll most likely swap the pistons out when I Supercharge the engine next year.

Unfortunately there is also an issue with the engine smoking badly on overrun, Damian feels it may be the valve guides that need replacing. I'll see how bad it smokes when I get it back and remove the head for inspection if need be. I hope that this is not the case as guide replacement is expensive.

The final issue is that the counter balancer has been removed which makes the engine vibrate quite badly without it. This is apparently often removed and thought to give more power, but is not really proven. These are quite cheap on eBay, so I can get one to try it out to see if it makes things better.

All in all, I guess that I have learnt a lesson that there is no such thing as a hardly used race engine, always assume that they have had a hard life and expect to have to pay for a refresh. In hindsight, I would have been better off with a stock engine for my build.

SBD Throttle Bodies & 690cc Injectors

Chatted with Marc on Friday and agreed that as Damian will be away on holiday soon for a month, the best plan would be to get my car mapped for performance this week and then sort the IVA afterwards.

The IVA issues that are to be fixed are the brake balance and the noise at 102.4db and needs reducing to 99db at 7680rpm (based on 3/4 of 10200rpm). Marc feels confident to sort the noise with a slight change to the silencer and and adjustment to my airbox.

In the meantime I went up to MNR today and fitted my SBD 50mm throttle bodies, 690cc injectors and a itg foam filter. I also fitted the flat shifter blipper and a new throttle cable. The car will then be taken to Damian at Daytuner for setup. As the SBD throttle bodies use aluminium velocity stacks they will not work with the standard airbox, have fitted a basic itg until I find at a better solution.