350 Mag Alpha 1 HP ?

[delmarjr]

I recently purchased a 1990 Stingray SVC 200 with a Mercruiser 350 Mag Alpha 1 and I can't find out the horsepower rating. The title says 230 hp but that seems a little low because it has a 4 barrel Rochester Q-Jet carb with thru hull exaust. It runs about 52-55 mph on the gps with a 23" pitch mirage prop. The outdrive sn starts with OC-------. The head #'s are 64cc chambers & 1.94 cc intake. Any ideas on the horsepower of this engine? I know the new 350 Mags with mpi are 300 hp. Thanks.

 

[Bondo]

Re: 350 Mag Alpha 1 HP ?

With the 4bbl. Carb..... It's Probably around 250/260hp......

 

[I/O WALDO]

Re: 350 Mag Alpha 1 HP ?

Sounds like a 260/350cid.Old way rated wuz at the crank(260)now,at the prop(230hp.inc.losses thru the drive)more realistic.(oh yea,mag.hmmm)

 

[Bonus]

Re: 350 Mag Alpha 1 HP ?

Does it have the highrise manifold? The 64cc cumbustion chambers prolly make a higher comp ratio. Similar year non-mags are 76cc I believe. None mags thar era were rated at 260 HP(old way as has been said)<br />Bob in CO

 

[delmarjr]

Re: 350 Mag Alpha 1 HP ?

It doed not have a high rise manifold and is all stock, what do you think the horsepower is?

 

[Bondo]

Re: 350 Mag Alpha 1 HP ?

Originally posted by Bondo:<br /> It's Probably around 250/260hp......

 

[delmarjr]

Re: 350 Mag Alpha 1 HP ?

Shouldn't it have more than 250 or 260 hp since it is a 350 mag, because I have seen a lot of 350 4 barrel engines that say 260 hp and 2 barrel engines that say 250 hp or does the mag logo not really mean any extra hp at all? I know the new 350 mags with mpi are 300hp.

 

[John_S]

Re: 350 Mag Alpha 1 HP ?

delmarjr, <br /><br />250hp 2brls, and 300hp mags were not available, until they came out with the vortec heads. They started around '96 with "gen+" engines, and became standard in '98. Many of the early 90's pre-vortec engines, had the same hp ratings for the 4brl LX and 350 Mag. Thats on paper. The mfg has some leeway in those paper ratings. ie the 350 mag might have been slightly under rated. What has been quoted (250-260hp) is what I have seen for this year level mag.<br /><br />A couple of things you stated, are contrary to what I was able to reseach. I am not aware of any stock 64cc heads, during that time period. While not impossible, I thought all the mags had the high-rise manifold, too.

 

[delmarjr]

Re: 350 Mag Alpha 1 HP ?

The head number is 14101083 which I looked up on the internet this is one spec I found----350 285HP, or 300HP, Crate Motor, 1.94-1.5, 72º intake bolts, 64cc chambers. The Alpha 1 S/N is 0c807009. Do these #'s help to determine the HP? It does not have a high rise manifold.

 

[muc]

Re: 350 Mag Alpha 1 HP ?

the serial number you posted is for a transom assy and has never been registered.

 

[John_S]

Re: 350 Mag Alpha 1 HP ?

delmarjr,<br /><br />That head number does indicate 64cc chamber, based on net documents I found. I rechecked mercruiser online parts diagrams, and they only list one part number for the 350 head. It is the same as what is used in 5.7L 2brl, and 5.7LX 4brl. Also rechecked DM book, and indicates only low-compression (76cc) heads were used in production merc, until vortecs. Doesn't mean that these sources are 100% correct, but I'd at least say that the heads are "suspect" to have been replaced sometime in its life. At this point, I wouldn't worry about the paper hp rating, just go out and see if the "true" performance is to your liking.

 

[delmarjr]

Re: 350 Mag Alpha 1 HP ?

Does anybody know if my Alpha 1 outdrive is a Generation 1 or 2?

 

[Don S]

Re: 350 Mag Alpha 1 HP ?

It's an Alpha I not a Gen II. Your transom shield is an 89 and the GenII drives didn't come out till 91.<br />Have a look at this service bulletin on engine ID,<br /><br /> http://www.boatfix.com/merc/Bullet/97/97_06.pdf <br /><br />You might also look for a metal tag on the block just above the starter where the bellhousing bolts on. That would give you the serial number of the engine.<br /><br />PS: What's the obsession of knowing the horsepower number?