Thats nice

Personally, I like the other orange one better. . .

You play around with SC12's and you would know of the limitations of both 12's ans 14's . The teflon is the first thing that is removed along with modifications to the bearings/seals and lubrication system.
Now have you ever heard of "pressurized rotor strip sealing" in a blower. It's used extensively on condensate vaccume pumps on steam turbines and auxilary blowers on big 2 stroke diesel engines that are running 3 bar boost. I have overhauled quite a few of them over the years ,so do some research and you can find out about it. Sulzer engines and some early MAN engines also used this type of blower.
However I would NOT recommend that this system of sealing is suitable for a high use road car.

The pic I posted is a honda T/C F4 head conversion, a modified SC14 and a set of 68mm pistons I did for a engineer I worked with on a Dutch dredge who races minis in Belguim where he lives.
The engine was completed and running but he blew it up just recently during a race meeting. I do not have any pics of the final set-up as I know how is been all put together.

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Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

Nice car, At what PSI are you injecting the water? Is it just water or meth too? I've just installed a water injection kit onto my sc12 setup and its off the rolling road on the 2nd for the setup, so any experiences would be gratefully received.

Thanks
Graham

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998 SC12 61atw

Given that the SC12 is on a 998, it can make some pretty high pressures in short bursts. . .I've seen up to 16psi on the guage.

I've set the water injection to swich on at 5psi via a pressure switch fitted to the manifold. . .any lower than this and the engine bogs down badly.

I've tried straight methanol, a 50:50 water/methanol blend and straight water. . .I couldn't feel any great difference between them, so I've just stuck with water. Given that I primarily fitted the water injection for cooling (not necessarily for performance) then straight water should do a better job in any case. . .

My water injection system is reasonably crude but it seems to be effective - I've used a late model VW Golf windscreen washer pump (capable of 40psi) connected via nylon tubing to an atomising nozzle (which, from memory delivered 70ml/min water at 40psi) that is positioned to fire directly into the supercharger rotors. One thing I do need to fit is some sort of check valve or solenoid or something - off boost, engine vacuum is enough to pull water through the pump and into the manifold wich can cause water to sit in the manifold or (presumably) in the chambers whan the motor is switched off. Probably not a good thing.

Without the water switched on, the car will start to ping badly at about 8psi boost (98 oct fuel). After an extended period of running, the main manifold it pretty much too hot to touch. With the water on (switched at 5psi) I cant get any detonation under any type of driving, even right up to 16psi (momentarily). After a decent run, the manifold is only warm to the touch.

You should probably take all my 'test work' with a grain of salt in any case at it's all been done by plug cuts and seat-of-the-pants testing - I haven't had the car near a dyno for tuning purposes. I know the car does run lean at the top end but i haven't had time to sort it out yet. I have a 1380 waiting in the wings to go in the car, so I probably wont do much more work with the 998 in any case.

Thanks for the reply. Ben made me a new manifold so that I can inject into the rotors too.

I have also used a VW (made by VDO) headlamp washer pump, I have installed a 12v solenoid and used 1/4 plastic piping and some push fit connections. I have a .35 nozzle and a .70 I have installed the .35 and setup the system to be fired + open the solenoid at 5psi... spooky. mine runs to about 10.5 psi at max revs. I have some mix but was thinking it would change the fuelling as I only have a 1l bottle installed I was thinking straight water would be best. the only thing over here is that we get stuff to freeze very easily.
I was going to use a switchable map so I could take advantage of the cooler intake temps and advance the timing a little... but will see if thats a good idea on the rollers.

DO you know how quick you get through the water?

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998 SC12 61atw

interesting stuff about the water injection - great stuff

I've set my ignition on boost to 14* and gotten rid of any pinging, but that's made it a bit sluggish. I think I'll do something with a water spray and see what it does for me

what plugs are you running?

Sounds like a remarkably similar system. . .where did you source the solenoid from - I assume it has small (1/4"?) fittings? the only 12V solenoids I could find at the time were dirty great 19mm garden reticulation ones. . .

I guess there's no reason not to add enough methanol to slow down freezing. . .although it is a fantastic solvent - it can be surprising what it can dissolve!

I'm using a 5 litre tank sitting behind the seat of the Moke. . .like I said in my earlier post, the 40psi pump and spray nozzle run at 70ml/min, so I have more than an hours worth of water on board, assuming I'm always above 5psi of boost. Realistically, though the water lasts a long time (about a week) under normal driving - I tend to fill it up every time I refuel. I'm sure I could also back off on the 70ml/min rate with a smaller spray nozzle to make the water last longer and still see a useful effect.

As for ignition, I've just welded up the baseplate of the standard dissy so that I've only got 10 degrees mechanical advance (20 at the crank) plus 5 degrees static and that seems to be fine. Plugs are normal old (and I mean old. . .) BP6's.

I've used brass LPG solenoids you pick up from automotive LPG installers. I paid about 30 dollars two years ago.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Ah hah:

http://cgi.ebay.com/ebaymotors/water-methanol-injection-stainless-steel-solenoid-/120686268216?pt=Motors_Car_Truck_Parts_Accessories&hash=item1c19764f38

mm I never put the tank in the car in case of the smell..

yep I use a lpg petrol valve, in fact I use two... one is to re-circulate the boost on over run so that it doesnt over fuel and stall when you come to a stop.. works great.

Megajolt was one of the best things I have put on the car after Bens sc12 kit . Ben also sorted the trigger wheel, bracket and sensor, lovely job.

Will let you know how I get on at the rolling road on the 2nd...

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998 SC12 61atw

I use a brass version of this...

http://cgi.ebay.co.uk/PETROL-Solenoid-S ... 4aa92d2409

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998 SC12 61atw

Is there an issue with pre ignition when fitting the SC12 on a 1275?

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http://www.youtube.com/user/Hanras

was it due to the teflon finding it's way into the inlet??

if you read the rest of the post, he said that he'd already removed the teflon and modified the blower