The EFI on the 993 Briggs starts and runs. It idles very smooth and starts in one revolution. I haven't hooked it to the computer yet but am very pleased so far.

Pics?

you da man

Hey stu, my PayPal is ready to go! Just say when

Here are a couple of pictures before all the wiring and plumbing was done. The ECU is fastened to the rear of the belt housing. This is a complete, "closed loop" EFI with O2 sensor, block temp sensor, intake air temp sensor, mass air flow sensor, throttle position sensor, high pressure pump and fuel pressure regulator. My next step is to connect it to my computer and tune it for the best performance. As far as I know this is the first time this mod has been done on the 993. I'll add a picture of a similar kit to the one i'm using. If you contact Ecotrons tell Matt you saw the one stu did.
Oh yeah, the kit shown uses a throttle body injection system. If you look close at the pictures you will see I went with port injection.

Impressive

Thats sweet.

Cool

Nice Stu, caint wait for your review

Sooner or later we will be able to buy big block EFI's, its just when. Until, them 25's are gonna go like hot cakes

bad ass!!! i wish i had the tinkering time alaska affords!!!

Do this and fix the case gasket issue and I will own another 35! Lol.....sweet job.

993 cc

Got it- DOOOH!

Hey buddy, when the water gets soft I want to go for a ride. When is Easter weekend? I'm thinkin Clearwater. Looks GREAT....Don

Good job Stu! It looks great.

Stu, What size throttle body did you use?

Did the efi on one of my motors in 2009. Was a complete kit from a manufacture that puts them on harly motors. Still have it sitting on the shelf at the shop. Set it up on an EVT vertical intake and tried it TBI and DFI. It did better with TBI. Had it installed on a motor and tested in California before shipping it here. Too many other things happening to mess with it again. Good job on your conversion.

Built a wheel that bolted to flywheel. Had 38 teeth on it with 4 missing using the halls effect sensor. Used different coils as well.

Stu: you should get one of these. In your creative hands it would be deadly, I'm sure: desktop 3d printer.

http://www.stratasys.com/lp/3dprinting/ ... Qgod3V8AKQ

I did a short video of the engine running and loaded it to utube. I'll do another after I tune it with the computer.
[youtube]http://www.youtube.com/watch?v=8cF2xJr5qb0&feature=youtu.be[/youtube]

All of this is over my head to say the least, but that was impressive!

set up a hydrolic motor to run off your out put shaft, through a gage set with a valve off the down stream side so you can tune and compare output at a given rpm. Kinda like a dyno. if you are pushing 4000psi at 3600 wot, and a adj gets you 35-- rpm at 4000psi it added hp.

Here is a quick update of the project. I haven't been pushing real hard since we have almost 5 ft of ice on the rivers and lakes so it will be awhile until I can put the engine under load. The instructions for tuning are not difficult after you have read them 8 or 10 times and figured out what is meant by some of the terms. Once I had the software working in the computer it became playtime. Right away I noticed the displacement was identified as 497 cc's. I said "that can't be right" this is a 993 cc engine so I changed it.
When I started it up it looked like a diesel under load. There was a beautiful plume of black smoke from the exhaust and I could barely keep it running. DUH!!! That must be the displacement of one cylinder. I went back into the computer and reset it to 497 and it runs great. The throttle body doesn't have any mechanical idle adjustment. Since it was idling at 1500 I wanted to be able to adjust that downward. Nothing to it. The 42 mm throttle body has a stepper motor that is controlled by the ECU, so I told it to idle at 1000 and it did. Then I told it to idle at 1200 and it did that too. The 28 mm and 35 mm throttle bodies for the single cylinders use a bleed air bypass to set the idle adjustment. There are several other adjustments I will make once it is warm enough to run outside. It gets a little close in the shop if I keep it running too long and some of the settings need to be made after the engine is warm. The cowling had to have holes cut in it to allow clearance for the port injectors. If I had elected to go with throttle body injection the cowling could have been left stock and I wouldn't have had to do any machining to the intake manifold. It still would have required the adapter from the throttle body to manifold but I prefer port injection. I fabricated two covers for the two holes where the injectors poke through the cowling because quite a bit of cooling air was escaping.
Those of you that are into hopping the single cylinder engines I encourage you to look at what ECOTRONS has for these engines. Of particular interest should be the EFI-Turbo kit. With adequate crank, rods, piston and cam I think doubling the hp is feasible without turning it into a grenade and still maintaining a reasonable idle.
More to come when the water gets soft.

This is fantastic and appears that the kit is $599 and you pick your throttle body. Any body else thinking what I'm thinking. Why the hell can you get an entire EFI kit WITH throttle body for $599 and that mikuni carb kit is $775. Something wrong there.

Looks good man. Wish I had the time to tinker with a project like this. My only question: did you get warren cocos good graces to mod his motor? Lol