Marinised PCM/Ford

horkn wrote: Not backpedaling at all. If you want to argue semantics, go ahead. 350's are known as 5.7's. While the 97+ vettes were 346 CI, they were still known as 5.7's.

Its not semantics. The 350 design dates back to the 50's. The LS series of engines was a clean sheet redesign for '97 that shares no components. Just because the LS1 (346) shares a similar displacement as the old engine and rounds to the same tenth of a liter doesnt make them "the same", regardless of what you think they were commonly "known" as- and I suspect youre not right about that either. The 346 shares little more in common with the 350 as it does a Ford 351w.

Like I said, you better stick to the Ford stuff.

We've had 2 Gm 350's crack on the lifter valley on the last 6 months, one was a '95 and the other a '98. We also had many, but many V6s from the mid 90's crack there too. All low hour engines.

We were discussing the cracked blocks yesterday, maybe a question of luck but all of them Mercruisers.

We have 2 4.3L blocks, both Vortecs, one out of a Bayliner Sierra 2350 and the other was on a 20' Runabout. I didnt water test any of these.

Then the 2 5.7L, one pre vortec (12 bolt intake) out of another Bayliner Sierra 2350, wot at 4700, cruising at 3300rpms and the other on the Tigé, this one a Vortec, Wot at 4500 cruising at 2400rpms (13x13 stainless prop)

Engines had good compression, worked good, just emulsionated oil.
All cracked in the same place, were the head bolts pull in the lifter valley. The Pre-vortec 350 was cracking all the way around on both sides.

The general consensus around here seems to be that the castings are too thin in that area and the amount of torque from the head bolts leads to the failure.

I'm yet to see a PCM, Indmar or even a Volvo crack like this.

you can distort a block and stress it if its pulled down unevenly on the mounts and tightened that way, you will cause some type of deflection in the casting. ironically, are they all 2 bolt main blocks? some tend to think the 4 bolt mains are so the crank doesnt come flying out the bottem, but in reality they are there for block distortion, (twist)

let me stir this up a little more. what if toyota marinized one of their v8s for inboard use. would you buy it? the v8s used in toyota tundras are lasting longer than most in its class. now that would be something to invest in, provided they make them in the us.

That would be the Toyota Lexus V8 Joe's talking about.

Toyota doesn't continue doing anything they can't make money on.

btw, where did you hear the engines were lasting longer than any in its class? toyota commercial?

eric lavine wrote: btw, where did you hear the engines were lasting longer than any in its class? toyota commercial?

If this is based on the 4.7 OHC v8 in first gen tundras, I guess I don't see it. That same motor is the same basic motor that the GS400 used, with different bore and or stroke, and that was the same as the epic ski boats.

Its a great motor, but I don't see it any better than the other brands, (well most of them).

The newer yota 5.7 is a very good motor, but I see no way to quantify it as better than he other brands similar sized motors, especially in only a couple of years of use.

Luc, it has a timing belt, and those need to be replaced or you have catastrophic problems. That's one issue I have with that motor.

Maybe I'm a bit cranky at our 4.7 4runner because it needs its timing belt done now. The water pump and pulleys should be done at the same time as well, so parts are about 250-300 for factory ones, and labor is another 250 or so. It's been a solid great performing motor, so other than an odd oil filter location on the 4runner that requires a trained weasel or dropping the skid plate to change the filter, I have no issues with it. It seems to want to rev a little more to make power versus other v8's too.