What makes an engine a "Vortec" and what dif does it make?

[John_S]

Re: What makes an engine a "Vortec" and what dif does it make?

I am happy with the upgrade. You end up with about 280hp at the prop. I started from a 210hp (2brl) @ prop.

I would make sure your engine is good condition before considering, also make sure the rest of the boat is worth the upgrade.

If you have flat-top pistons you will have too high of compression, IMO, for a boat engine.

 

[TilliamWe]

Re: What makes an engine a "Vortec" and what dif does it make?

A 1987 motor should have had dished pistons originally. If that was what was put back in during the reman, the Vortec heads should work well. While you are swapping heads, you should install the roller camshaft that true Vortec engines get as well. That's the real way you'll get to 280hp at the prop.

 

[tmh]

Re: What makes an engine a "Vortec" and what dif does it make?

OK, since I was the OP of this thread, I see it's been brought back to life and I still have a question. OK, so it seems IF I have the 8-bolt configuration it is Vortec heads. I'd like to check the S/N or P/N for the engine and the heads to see if it is indeed a mod to the original engine or just exactly what I have. Where do i find these numbers? My engine cover piece does not have a S/N listed and i don't think I'd trust it anyhow as it could be from any engine. Just as a refresher, it's a 5.7L 350 Mag Mercruiser I THINK from early 90's.

Can anyone help me find the ID plate on it? For the heads, can I find the ID with the engine installed in the boat? Where to look?

Thanks.

 

[Bondo]

Re: What makes an engine a "Vortec" and what dif does it make?

and I still have a question. OK, so it seems IF I have the 8-bolt configuration it is Vortec heads.

Ayuh,..... Have you even Looked,+ Counted the bolts,..??

As for the Secret/Number you're lookin' for,....There probably Ain't 1....

If you have Vortec Heads,.. Or think you do,... Count the Bolts,... That's how they're Identified...

Otherwise, you'll have to pull the Valve Covers to see the Casting #s....

If this motor has the original Mercruiser block,...
There might be an aluminum tag riveted to the block, just forward,+ slightly above the Starter,...
Lower starboard side aft end of the motor....

 

[tmh]

Re: What makes an engine a "Vortec" and what dif does it make?

I've looked, yes - did so earlier today again, as a matter of fact. IF I'm looking at the correct part, yes, there are 4 bolts visible on the port side and I assume 4 matching ones on the other side. Why I was asking about ID #'s is to try to find out what year the various parts were from. The casting # is what I was thinking of and had heard about here before but sounds like it's not happening. I will look again for the engine block tag - I wasn't looking in the right spot I guess.

 

[John_S]

Re: What makes an engine a "Vortec" and what dif does it make?

Most likely an engine replacement or modification. Vortec engines were mid-late 90's. A 350 Mag with vortec heads would have been a fuel injected engine. Take the flame arrester off and post a picture.

 

[John_S]

Re: What makes an engine a "Vortec" and what dif does it make?

While you are swapping heads, you should install the roller camshaft that true Vortec engines get as well. That's the real way you'll get to 280hp at the prop.

The roller cam was introduced before vortec heads came out. The std flat hyd cam is fine and produces the same hp.

 

[Mkos1980]

Re: What makes an engine a "Vortec" and what dif does it make?

As posted on another site, I'm doing the same swap. 906 Vortecs, Edelbrock RPM Air-Gap, LT4 Hotcam, GMPP 1.6 Roller Rockers and a set of Beehive springs. Identical combo minus the headers = 401HP from CarCraft Hoping for 380 with my Revolution Manifolds. Should put me around 340-350 at the prop.

 

[tmh]

Re: What makes an engine a "Vortec" and what dif does it make?

Mkos, in the 2nd photo I see the 8-bolt holes on the top......Is THAt the intake manifold I'm looking for to determine if I have a Vortec? Do you have a photo of it from the side by any chance?

I'll get a few pictures of mine when i have the boat home again this coming weekend. I should have done that months ago.......never thought of it.

 

[Mkos1980]

Re: What makes an engine a "Vortec" and what dif does it make?

Thats the one.