Carb to EFI conversion

[h2oski]

I am converting my 1991 200 2.5 fishin motor to EFI. I have everything, at least I think I do.

Does anyone have experience doing this, tips, things to watch out for???

Also, can anyone provide me with pics of a similar powerhead so I can see where things go. My biggest concern is the wiring.

Any help much appreciated.

[sosmerc]

Fun project...and I've done it before also. I put a Laser 220 EFI system on a '91 2.5 carb 175 powerhead...and it worked out fine.
Mine was pretty close to stock. I did use Boyesen reeds and I had my heads milled just enough to insure they were flat. My compression was 140-145psi all cylinders. I ran premium just to be safe. I removed the oil injection as well as the onboard spin-on filter and the water sensing device. I also removed the detonation sensor. I ran 23 degrees advance and ran Amsoil injector oil at 40:1. Used a holley red to push fuel to the engine through a Racor water seperator. I left the diaphram fuel pump on the engine as well. I ran dual egt, and also monitored both my low and high pressure electric fuel pumps. Never turned it up much over 6200 rpm and usually saw between 1200 and 1300 degrees (my probes were in the exhaust cover, not the adapter plate). I had the 40 amp charging system with dual regulators.
I recently sold this powerhead and now will be doing a similar project this winter. I have a 91 200 2.5 Carb powerhead that I am also going to put EFI on. Was thinking of building it with Laser system first, then want to go to MAD front or SVS. I'm sending 6 injectors to Tony Brucato for their "deluxe service" first...to be sure they are all flowing pretty close.
This will be a seven pedal reed setup, and again, I will use Boyesen reeds. On this powerhead I think I am going to switch to top-guided rods and pistons. Since I do not intend to exceed 6500, I think I am going to try the Pro Marine cast pistons. I am also thinking of using either a 9 amp or 15 amp system and smaller flywheel (just to see if I can notice any difference in performance). Powerhead will be going on the same driveshaft housing and boat....so I'll get a good idea of whether or not I've gained anything over the last powerhead.
The only thing that required any special attention on the last conversion that I remember is: I had to elongate a couple of the intake manifold holes in order to line things up. And I think the bleed system routing took a little "thinking thru" as well. But in the end I was very pleased and I'm excited about getting going on my next one...just wish I could finish up all the paying jobs so I can get on with it!!
Sorry I don't have any pictures of the powerhead for you, but you really should pick up a factory manual for your model anyway.
Send me your powerhead serial number and I'll see if I have an extra factory manual for it...if so, I'd sell to you for $10 plus shipping.
Let me know if there is anything in particular you might need...I do have quite alot of v-6 stuff, and I have access to parts at reasonable prices and will sell at my cost plus 10% which is very similar to others in the business on this site.
Good Luck on your project!