K1100 1360 build W/offset bores
Turbo Mini Forums

Hello guys been wanting to do a K1100 build forever finally got around to doing it. So far ran five minutes but the Carb did not work out so the fuel injection is currently going onto it. Aaron
http://s1346.photobucket.com/user/Hydrolas...m?sort=3&page=1

Edited by hydrolastic on 28th Jul, 2015.

Racecar spelled backwards is Racecar

Hello everyone, Gregg, (the originator of the k conversion) came over and we started on the fuel injection. Since i had not planned on using FI there are a couple of items that need to be changed. First i need to make a crank sensor bracket. Next i need to get the coil and wires figured out cause the coil is a ford gen 1 zetec coil and the leads into it are different. I plan on using the typhoon ECU for this engine only because it is leftover from another project. Anyway Gregg and i mapped out the connectors needed to make a harness. Since the carb failed i had to get the TB's replaced as the RS tb's are too big for the k1100 head i have. At least thats what the computer engine sim program says. A buddy of mine has a mini that is between engines right now and i am installing the Khead engine to do a mock up of everything needed to get this puppy running and back into the race car. Just letting you know i am not familiar with much more than the basics of fuel injection so i will be on a steep learning curve here. There are however a couple of easy parts first the car i am using has an MPI tank and pump already in it and it is a 3.5 bar /51 psi unit and the bmw injection system is also 51 bar. Also i am going to build a new exhaust system into the car as the SC system is a 2" and the regular mini system is 1 7/8 ths. I want to make sure the system is as free flowing as possible cause the computer shows that any less than 300 cfm causes a good reduction in HP. Will keep you posted on how it goes. Shooting for the engine to be running by the first weekend in september. Aaron

Racecar spelled backwards is Racecar

Sounds good. Any pics?

My build thread..

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=542985

Wow how cool

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

Hello, Added more pictures including how the bores were moved
http://s1346.photobucket.com/user/Hydrolas...m?sort=3&page=1

Racecar spelled backwards is Racecar

Hello turbo's, I started the conversion at christmas and figured in a month or so i would have it assembled. Instead it took 7 months! First problem was in looking at the conversion i wanted the change and hopefully improve a couple of things. First was the bore centers. I wanted to center them up properly to the head. How to do it posed a couple of problems. Because i was enlarging the bore to 73mm i could move the end bores inward .028 but i needed more to get it exactly on 76mm. I settled on a true 3" bore center this meant that the two center bores were .008 wider and the outer bores are out .016 close enough for my garage. I then got a set of A+ rods and removed .030 off the outside of the little end because the bore moved inward. To clarify i am doing two engines at the same time one for me and one for a friend. The first engine has run on a carb the second engine is still in bits. Then i plugged the holes. On the first engine i used brass pipe plugs and steel grade 5 bolts for the old stud holes. My machinist cursed me for this but surfaced the block anyhow. The second block i rethought it and used silicon bronze bolts and pipe plugs I chose silicon bronze cause it is easy to machine but it is stronger than the brass. it is however hard to find solid plugs eventually i found them they are used only in commercial water systems. plugged all the holes and started on the drilling. Couple of things to note i decided to use the hollow dowels used to locate the head on the block but they are an unusual size 12.5 mm . Made up a couple on the lathe. Since i was relocating the head from the SC kit all ten studs needed to be moved on the first block i used drill bits on the mill but they kept drifting off into the softer plugs. On the second block i used milling cutters 1/4 then 5/16 no problem after that. Once i got the mainstrap ARP bolts figured out i sent the crank rods and pistons to the machine shop and he bored and skimmed the block. He also installed ARP bolts and resized the rods. With the engine bored i clamped the gasket between two pieces of plywood and used a laminate trimmer to match the gasket to the bores. spent a day deburing the gasket but when i was done it fit perfectly. Engine assembly went normally after this. Next i got the kits from SC and the real work began. First problem during the mockup were with the pulleys. I had started to install one and halfway on it just seized on and would not go on or come off. Took me four hours just to get the pulley off again making special tools along the way. I then disassembled the pulley's chucked and indicated the bores and after a couple of .0005 cuts they were a hand press fit went to assemble it and the end bolt on one of the cam adapters was not able to go in. i ended up using valve grinding paste and the shank of a close fitting drill to open up the holes. Then the rest of the kit went together fine with some work to get the cam end thrust right. There was another issue with the top pulley's cause the keyways were machined in tilted. i ended up running them together in a vise with the key cutting its own keyway. Assembled it all together again. The tensioner was another issue and the pre A+ block needed a bit of fettling to get the tensioner to go loose enough. Then continued on and degreed the cam. There was an issue with this and it took a couple of tries to get it right. I never understood the method that SC talked about so i just used the centerline method. Not having done a twin cam before it was just a mess then one morning i woke up and the first thought was "do the exhaust first" gave it a shot and the numbers fell into place. Took a while to get the intake manifold together but finally it was time to start it up. Fired right up and it really sounded good and then the problems started….First it was a miss that got worse as i leaned out the HIF44 it got better then worse again till it would not rev past 3000 the plugs were fouled so cleaned them and again it sounded good but a minute later it did it again. The manifold and carb system just was not working. So the plan now is to get it fuel injected. So thats the story of the k1100 engines. Now I start on the list of items to get it running again. Aaron

Racecar spelled backwards is Racecar

Hi Aaron

Great project.

I will be doing a similar engine mod, and want to re-centre the bores too.

Can you give me any advice about this? I'm intending to use sprockets approach. Overbore then line and run +20 tho over bore from standard.

Cheers

Nathan

Hello Nathan, So not quite understanding what you are saying with the over boring.
lets start at the beginning the standard bores are 3" between 2 and 3 and the outer bores are about 3.028 between 1-2 and 3-4 so to move them inward to a true 2.992 (76mm) then the overbore from standard needs to be at least .020 for the just the center bores but now you have the problem of moving the outer bores to a true 76mm this means you have to cut the outer bores .028 to get them at a true 3" or another .004 from the center bores plus another.008 for the outer bores then the .028 so the outer bores centerline need to be moved .040 then you double that to account for both sides of the piston to get it round again thats a .080 overbore just to get it in the block. Now my machinist says he wants at least a .020 to do his work from there so thats a whoping .100 overbore now the pistons i use are 73 mm or a .094 from standard so thats why i went with the 3" bore centers cause i could not quite get the 76mm or 2.992 centers to work and still give the machinist his minimum .020 to clean up the rough boring i did on my bridgeport mill. Now at first i thought that the way SC did it using the existing studs was crude and more hp could be found by properly centering the head on the block since now you have to move all the front studs over .068 or so from memory. but since then i have realized that by using the existing studs the intake valves are just a bit more towards the center of the bore and are unshrouded a little better so it is probably a moot point. It does however allow you to use the BMW head gasket which on the US bike is a huge .065 in thickness and 4 layers thick after the 73.mm (2.874) pistons were pocketed i measured them at 9.5 cc volume so then i removed one layer from the gasket and ended up at 10.4 compression which according to my calculator allowed me to use a 9.20 to one dynamic compression with the 254 cam and 9 to one on the 266 i plan on using later. some people say you can use quite a bit more compression with a pent roof chamber but i chose to replicate the BMW dynamic compression of 9.18 or less
so what you are saying is you want to move the bores over but you only want to go with a .020 overbore does not quite work. Aaron

Racecar spelled backwards is Racecar

Nathan was talking about the way I did this by installing cylinder liners. Offset bore for the liners which then bring the bores back to STD or +0.020.

I did this way back in 2008.

Hello sprocket, Yes i think i saw that on EFI minis but thats gone now. How did that engine work out?

Racecar spelled backwards is Racecar

Ran great when it was in one piece. I suffered a center main bearing failure and the later that year melted a piston with NO2 . Rebuilt the engine with forged p istons in 2010 but not yet had it running due to general life experiences and other stuff that becomes more important. Watch this space...

Engine is running! put it in a friends mini. Fitted the fuel injection and it is Awesome!
http://s1346.photobucket.com/user/Hydrolas...html?sort=3&o=0

Racecar spelled backwards is Racecar

Hello Turbo's, Last week we went to the Dyno. All went well and the SC map was a great starting point did not do much to the 1000 rpm to 3000 range but did a bit to get the 3000 and up dialed in for a 13 to 1 AFR the engine made 86 Bananas and 74 torques this is at the wheel so with a /.8 conversion it comes out to 108 hp and 93 tq. Not as much as i was hoping for… BUT what i did not realize it the amount of tq down low and when we started driving it holy cow this engine pulls hard! http://vid1346.photobucket.com/albums/p694...zpsqhjjb3fl.mp4

Racecar spelled backwards is Racecar

Similar to my 1275 and looks about right for the LT cams, though I'd expect a little more torque with the bigger bore so I expect there is more to come from that. I'd start by running the fuelling to 12.5 AFR where I know you will find more hp. Also, ignition wise, they tend to run less advance, around 28 degrees full throttle.

Just noticed that the dyno pulls were without air filters...... do you intend to run filters? I hope so! And not those bits of foam either. You are better placed to source some K&N filters or similar (I have the info for some motorcycle fillers ideal for these!) And bin off those trumpets, since the trumpets and foam socks make less hp than just the K&N filters!

Sprocket, The filters are a problem we will be coming up with something not sure what though but really on track we just need to keep the tire rubber out. The next race is at the end of the month so we will just be getting a crude something on it.
Before i forget here is the giant slalom
http://vid1346.photobucket.com/albums/p694...zpsennozuax.mp4

Racecar spelled backwards is Racecar

Hello Turbo's. The first race is over and we won fourth in class C and 43 overall with a 70 car field. Great for us! We would have done better but i spun out on a 60 mph corner and collected a bmw head on, spun me around again and i thought the race was over before the first day was ended. We pulled the front end off and pounded out the metal and the starter was broken. luckily i had put a spare in the box but almost didn't. The collision was above the subframe so it was still straight. less than an hour afterwards i was back out on the track. The rain had stopped and the track was dry so i started to go faster each lap. The engine sounded great and was really putting out the ponies almost everything about the twin cam was better. it was smoother wanted to hit the rev limiter all the time, stayed cool. Usually with the five port the engine is blistering hot. This one could have gone for a cruise it never went over 180 f no matter how hard we drove it. One thing i would like to change is the throttle bodies as i am sure the engine ate a lot of debris. i am partial to a plenum type manifold. I may change the intake cam. The LT cam is just too mild at least for the race car.
The best part was the fact that at the end of the race it was running better than it did at the start. So the conversion is sound and there was only minor issues. One issue was over the 16 hours we used a qt of oil it seems to be coming out of the water pump area and the fan sucked it up and put it through the radiator. Cant see where it is coming from . Thats it for now, it's on to starting the next one(mikes) and after that i have to make a spare engine for next year.

Racecar spelled backwards is Racecar

K&N's!! 4 individual 36 or 40mm ID universal K&N's not only look good, but do exactly what it says on the side of the box. The do an offset tapered version that's an easier fit.

Not convinced you understand how much crap the engine will consume even on a track! NEVER! Run without a filter be it paper, foam or cotton. That's advice not from me but Dave Vizard. Again, a good cotton gauze filter outperforms everything. A decent paper filter is actually better flowing than an oiled foam filter. A dry foam filter is just a waste of time. Dont be 'fashionable', foam filters are not cool

Hello Sprocket, I agree with you an air cleaner is important for any car racing or not. We just ran out of time. We did put some nylons over the trumpets. The object of this engine was to just see if the head would work. We are not going for super high hp on this one. Just experience what it takes to build one and if it had any defects that would show up. The captain of the team took the checkered flag and said it was running better at the end than it was at the beginning of the race. We made a few adjustments along the way one was to reduce the fuel map a couple of times for a total of 10%. This we figure to account for the altitude. Salt lake city is at 4400 feet.
The next engine is not for the race car but it will get a whole host of improvements and the engine after that will be for the race car and will incorporate the improvements also. stay tuned
Aaron

Racecar spelled backwards is Racecar