Kawboy's restoration/conversion of a 1980 KZ13

scotch wrote:

That is a beautifully compact "Coil-Block" !   Beats the crap outta dealing with 3 individuals and looks appreciably smaller then my GM coil. 

And here I thought you were going to say " Jesus KB you got a big hand"  LOL (Truth is I do have a big hand XL glove size)

Yes, it's small. It will easily mount in the place where the 2 lower coils go. This coil pack has impressive numbers as well.
Duration to achieve saturation 3 ms as opposed to the stock coils of 8ms. because the primary resistance is .9 Ohms instead of a total of 3.2 Oms like the stock coils with the resistor. and with the Microsquirt, no ballast is required.
Spark duration is 2.8 ms. Most coils have a duration around 1.2 -1.5ms.
Doing the math, at 8000 rpm, you have 7.5 ms to charge the coil and discharge the coil and with this coil, charge for 3ms and 2.8 to discharge still leaves 2.2 ms in between cycles so at redline, the coil will still be providing a full spark. With the stock coil because the coil needs 8 ms to fully charge plus a discharge of 1.2 ms , at redline, the coil can't fully charge before it's asked to discharge and then immediately have to cycle again.

Output is 58 Mj which is slightly higher than a stock HEI coil and I can tell you from personal experience, you don't want to get lifted from a plug wire from a HEI system. It will knock you flat on your ass. Having a high output coil with a long duration spark gives you the opportunity to run leaner mixtures if you have the equipment to do so. Combine this with the Microsquirt and a fully self programmable fuel map and things could get really interesting.

I just need to get my shit together and get on with it.

biltonjim wrote:

This is interesting. I'm really looking forward to seeing your ideas take shape!   That's a neat coil pack - hopefully easy to find space for on the bike frame.
Regarding cleaning of the cylinder block, would  Scotchbrite wheels of various grits, mounted on a rotary tool or a drill, make the job easier? 

The problem is that the really bad areas on the liners are where the o-rings have to seal. The pitting needs to be filled in because the area where the o-rings seal is also an interference fit to the block. I think what I want to do is set this block to the side for now and refurbish another cylinder block that I have and get on with it although after having pulled this one down and cleaning everything up, it would be wiser to carry on with refurbishing this block. My biggest reason for wanting to go with this one was to get LA Sleeve to make me new cylinder liners to go from the stock bore of 62mm to a bore of 66mm and use the KZ750 pistons I have, building a REALLY BIG BLOCK   66mm bore x 71mm stroke = 1457cc    Ay Karumba !!  The liners would set me back $189 USD x 6 = OUCH !!

It's all fun and games.

These might be a better size representation

 
Almost identical to the length of the stock coils

 
Twice the height of the stock coils

 
A little bit less than the width of 2 coils

And weigh about as much as 6-8 of the stock coils. the thing is a beast at 4.5lbs  The stock coils are about .4 lbs each

Could that coil be used on a conventional OEM system if appropriate ballast resistor was used?

Probably. You would have to use a 2.2 Ohm ballast resistor to keep the primary power draw down to a level that the stock igniter could handle   It would take some research with an oscilloscope to get it right. The next question would be if the coils would saturate enough to give a healthy spark. The limiting factor as I see it is the power allowed through the stock igniter because if I remember right, the Darlington transistors can only handle 8 amps of current. 
The quadspark igniter I now have uses IGBT transistors which can handle power outputs of 30- 50 amps maximum depending upon the model of IGBT so now the limiting factor is the coil itself. Using low resistance coils means you can reduce the dwell time to charge and that opens up the frequency of cycling. The only way all this is going to work is as an entire system using an ECU to program the duty cycle.

It's been a while since I wrote anything on the "restoration topic" but I have been working on the bike. Last couple of months have been restoring a cylinder block and I'm almost done and this was covered in topic  Cylinder Sleeve Removal / Replacement  so for the purposes of documenting the restoration of the bike I'll do a recap of the cylinder block refurbishment.

Cylinder Sleeves removed by heating the cylinder block to 300F on the BBQ tor 1 hour, then knocking out the sleeves with a block of wood and a light hammer ( 5 minutes).



Sleeves were initially cleaned with a smooth lathe file to remove the major crud and for the most part the sleeves were fine. The crud was really heavy and concerned me because the crud would act like an insulator and resist transferring heat from the cylinder sleeves to the coolant..








 I wanted to protect the sleeves from future corroding and investigated options similar to wet sleeve manufacturers options like Parkerizing but decided to Cerakote the sleeves instead. Cerakote has a ceramic coating called "Blackout" which is primarily designed for corrosion protection on firearms and one unique property of this Blackout is that it is high in thermal emissivity meaning it promotes heat transfer. The other unique property is that it is very high in corrosion resistance. Corrosion testing is done with a wetted surface in 90 deg. F. until signs of surface rust are indicated. this stuff timed out at 4000 hours where Parkerizing was less than 100 hours. So , I elected to Cerakote the sleeves and they turned out better than I thought they would.



I also had a casting flaw in the aluminum block that concerned me. There was a small area of porous aluminum beside the upper flange of one of the cylinders and this is a sealing area of the head gasket. JB Weld has been applied and I'll dress it down before installing the sleeves back into the block. 



I had a lot of fun  doing the Cerakote on the sleeves so I decided to Cerakote the pistons as well. They have a piston coating for the crown which is designed for Low thermal emissivity ( the ability to insulate heat) to help keep the pistons cool which will also reduce the heat soak keeping the engine oil cooler, so I just received that and also Cerakote piston sleeve coating for the thrust faces of the pistons. I'll be adding another topic on this process shortly.