No I havent, havent seen a mefi3 small block in person , sorta strange that some got TBI, some got mpi and some got Carbs even in the 90's.

I have burnt sleds down from stale premium that had water in it or station owner lied about octane in remote towns in Upper Peninsula of Mi.
Around here most gas stations have a "premium" tank and a base gas 87 octane tank, the 89 is mixed at the pump as it dispenses. I bought 20 gallons of 89 at the same shell when I first started tuning this then 15 gallons more and at 36 total timing would only get fractional KR (less than 1 dgree) IF I loaded brake too long/made really slow pull where motor was maxed out and not barely climbing. All of a sudden this week its got 3-4 dgrees KR on latest batch of 89 from same station with same tune, same afr, same timing, distributer not touched etc and we know its NOT mechanical since it goes away with 93.
The tach drive adapter on the dyno going to the depac was acting up last week, took it apart, shimmed spur gear in it, seemed ok for a day then at end of this latest test it started faltering again so no more dynoing till new one comes from Depac and Depac box is re-programmed to recognize it as it turns crankshaft speed and old one was geared down 2-1.

Efi or carb? I had a 2 stroke snowmobile that was a octane monster and everytime I got crap premium it blew up, It took me a while to realize it wasnt from a lean condition but a lack of octane. When it would blow up from being lean it burnt center of piston away then did a 4 corner seize/scuff from the heat expanding the piston. When it would pre-ignite detonate it burnt side of piston facing exhaust port and crown into the rings on exhaust side. So thats why I ask if efi or carb, did you end up giving it a little more fuel to be "safe" when you re-assembled it or it was definately octane? did it scuff the pistons, break rings or tulip valves?

Not sure, big blocks love duration and lift if heads and compression support it BUT keep in mind that these intake restricted motors as you add more duration and lift to move hp peak up at a certain point it will give up more tq than the hp it gains since the intake runner length will keep it at 5600 or 5700 modified and even lower in stock form although a 525 efi cam COMES from a restricted intake engine! Would be interesting!

You sure you didnt have a porous case that leaked when hot?

The 95 350 Mag EFI/MP had the same throttle body as the big blocks when they were MEFI 1. Thanks though.

It took out the side of the piston near the intake valve. I didn't add any more fuel as I added 2 jets in the secondaries 2 years earlier with all the ethanol horror stories. It didn't scuff or break rings. Even the valves were good. It happened at 4500 RPM as well. It was odd!

I decided to go with the 500efi cam because I thought the 525 might be too much. either Dart IE or EQ heads. Engines will be 9.1:1 with a 118 cc chamber. Also sent him info about having tpis do his throttlebodies. We're gonna do the mill work on the intake as well.

Any guess on numbers?

I see by your screen shots you have a DePac System . Hows it treating you?

515.88453hp more w/ the 525efi cam