225 efi 3.0l kicking my tail...

[Merctink]

January i got my injectors back from Brucato. New CCM reeds. Done some gasket matching and such on the intake. Set TPI and crank trigger. New orings in fuel system and all the goodies. Engine ran like a new machine until last week. What looked to be paper element from the spin on filter lodges in the VST float. Flooding engine to the shutters. So I fix the issue and go through setup again. Checked the crank sensor for .040 off a tooth and checked TPI. Tpi sets .95 idle and will never see more than 3.75 WOT. Engine has gone from 55-5600rpm at 70mph to 5300rpm and 65mph. I put new Ql77cc plugs in when she flooded out. So yeaterday fedex dropped off my long awaited 4 shutter intake. I get that all on along with my 250 ign ecu. I left the 225 fuel on it. Test ran it today. Maybe a tad better but not much. I did notice my tachometer started reading high today and tells me the supposedly new 250 ecu could be bad. Can a man run the 4 shutter intake with 225 fuel and ign ecu so i can see if that helps calm the tach or will that get me too much air? Ive done all i can to get the tpi to get to 3.95 at wot and it wont. Setting with a good fluke meter and all temp sensors unplugged. This thing is eating my lunch. Any help appreciated. I have checked everything obvious and went through linkage setup and timing twice. Im about to get my sledgehammer....

[R.grover]

I have many 3.0l mercs and have run 3.95-4.30 wot and .90-.100 at idle.
Now some 225hp 3.0l motors did come out with a 4 butterfly intake.
I have run best with 300pm ign and 250xb fuel.
250xb has 4degrees more timing than a 225hp and 250rpm more revs
300pm revs 6400rpm

[Merctink]

yeah I for some reason swore i ran mine 3.95 WOT before. maybe it was the 3.80 merc says. 3.75 doesnt bother me that much i guess. i cleared my head and went back through and found the fuel line collapsed as it came through the cowling. i would assume thats the source of my top end power loss. Ill run it tonight. just to be clear, i am good to go running my 225 ecu's and 4 shutter intake until Simon gets my spares re flashed correct? thanks for the help

[big tom]

Good info !!. please continue!.

[Merctink]

Ill be water testing later today but im going to give the 250 IGN ECU another go. I founds a collapsed line at the cowling. I have another post warning about this but I also found the inlet screen on the fuel regulator plugged shut and half the fitting full of junk. I just cleaned the fuel system and had Tony run the injectors. Wish I had known about the screen at that time. most of the junk was rubber from fuel lines and o-rings. Ill keep everyone posted but on the water hose it ran like a totally different engine.

[big tom]

When you pull the inlet screen is there a gasket?. Just wondering if I should have one on hand?.

[Merctink]

When you pull the inlet screen is there a gasket?. Just wondering if I should have one on hand?.

There is an O-ring between the outlet of the regulator and the VST. There is also an O-ring between the brass 90* fitting and the regulator. My two looked okay and sealed back just fine. The screen itself is pushed into the brass fitting so you will have to pop it out. A fairly easy task. Its a dome shape with the top of the dome meeting the fuel first. I think the level of junk in the screen will depend on the integrity of the two hoses coming from the VST to the fuel rail. Most junk before that should be caught in the other filters. That could be just my weird thinking too... anyway, I wish i had taken the time to take pics. mine was a mess