Mercruiser 370hp Motor Question

[Greg Guimond]

Anyone have feedback on this motor? Guy said he had a 7.4 Magnum vintage 1990 in the boat but then finally sent this picture over which was tough to get out of him. What year is this do you think? Is it better or worse than the Magnum model that made 365hp? Thanks

[BUIZILLA]

I thought the 370 was for the TRS era and the 365 started the Bravo era, but i'm not 100% positive...

[Greg Guimond]

The boat it is in is a 1989 with a confirmed HIN. It is attached to a Bravo One drive?

[Greg Guimond]

I think I dug up the information ............I'm not sure why a 1989 HIN would have a 1987 or earlier engine in it but it looks like the 370 is a good motor.

Let's see, for the Mark IV, Gen V carbed 454s

330 TRS 1977-81 Merc Trans
330 TRS 1982-87 BW Trans
370 1979-87 (predecessor to 454 Mag)
454 Magnum (7.4 Magnum 330hp) Alpha Drive only 1986-88
7.4/330 1988- Bravo
340 inboard 1981-1987
454 Magnum (365hp) Bravo 1988-97
400 cyclone 1980-86
420 & 425 1987-93
475 Turbo 1981-85
525SC 1991-96
450 (roller cam) 1995

[Ed Donnelly]

My 85 Criterion came from the factory with a 370 h.p. in it tied to a
TRS. ..Ed

[Greg Guimond]

Thanks Ed. I guess the thing that would worry a buyer is the fact that the Mercruiser 370 motors had a long 9 year run. Who knows if you are getting a 1979 or a 1987. Back when the boat was built in 1989. Mercury probably had a leftover sitting around as they were transitioning to the 454Magnum series and gave the builder a deal to move it off the shelf.

[Conquistador_del_mar]

Back in 1977 when I ordered a 24' Excalibur, you could order the 330HP or the 370HP TRS drive packages. The 370HP was a 4 bolt main block where the 330 was a 2 bolt main.

[BUIZILLA]

I thought the 370 was for the TRS era and the 365 started the Bravo era, but i'm not 100% positive... so, i'm right? :yes:

[Ed Donnelly]

so, i'm right? :yes:

Not too often you are wrong. Ass kissing Ed

[Greg Guimond]

So the 370 High Performance actually had a 10 year run, 1977 to 1987. And I guess that 370hp rating was flywheel so maybe only 350hp at the prop when comparing to today's motors.

[Greg Guimond]

I found this excellent picture of a 420 TRS. Does anyone happen to have a photo of an engine bay with a 370 motor to compare to? Thanks

[BUIZILLA]

370 had a Qjet, otherwise it *looked* the same as a 420 which had a Holley

[Greg Guimond]

Thanks Jim. I never knew if the 330, 370, and 420 all had 4 bolt mains with the better internals back in the day.

[Greg Guimond]

When I look at the graphics of the 370 Valve Cover below versus that high res 420 photo it almost looks like the 370 label has been messed with.

[Ed Donnelly]

This is off my 370 in the Criterion SS ..Ed

[Conquistador_del_mar]

Thanks Jim. I never knew if the 330, 370, and 420 all had 4 bolt mains with the better internals back in the day.

Greg,
I am almost certain that the 330HP was a 2 bolt main block - at least in my 1977 24' Excalibur with the 330HP TRS setup.

[Greg Guimond]

This is off my 370 in the Criterion SS ..Ed

Thanks Ed, your picture eliminates any doubt that the motor is a 370 in the boat. The seller has been a real gem to get info out of. Based on the comments and the chart below the guy could have anything from a 1977 to a 1987 motor in the boat. A little different than the 454 Magnum that he said he had. My understanding is that the Mag made 365hp while the 370 TRS made about 350hp.