Identifying Vortec heads???

[180shabah]

OK, the easy part, I have a '96 4.3LX 4bbl. I would like to be certain which heads are on this engine. Here is what I know, the valve covers are stamped Vortec(I know this means nothing), The original spark plugs were AC MR43T's with a reach of .460" and the intake manifold has six bolts per side for a total of twelve.

Here is what I think I know, IM's used with the vortec heads only have four bolts per side (total of eight) and use spark plugs with a reach of .708"

Is this correct, and do I have the older style heads???

 

[Reel Poor]

Re: Identifying Vortec heads???

Is this correct, and do I have the older style heads???

Yes and Yes

 

[Don S]

Re: Identifying Vortec heads???

What's the serial number of your engine. Just because you have a 96 boat, doesn't mean you have a 96 engine.

 

[lilmandavis]

Re: Identifying Vortec heads???

how many valve cover bolts? that and intake will always tell..

 

[Rob454]

Re: Identifying Vortec heads???

vortec heads have center bolts. the bolts are in the middle of the valve covers. the older non vortec heads have the bolts on the lips of the valve covers
Rob

 

[TilliamWe]

Re: Identifying Vortec heads???

Rob and Joshua, the valve cover bolts is not the way to tell. there are heads produce from 1987 thru 1996 that have center bolts, and are definately NOT Vortec heads. (They have six manifold bolts per side with the center two at that goofy 75 degree angle instead of 90) The intake manifold bolts is the visual way to tell. When the head is installed on the block, the intake manifold bolts will be vertical. Also there will only be four bolts per side, not six.

 

[TilliamWe]

Re: Identifying Vortec heads???

180Shabah, my vortec 5.7 uses MR43LTS spark plugs. And they are a longer reach. Those MR43T is what my Dad's 1983 260 (5.7) and a million others used. Those plugs and the six bolts (are the center two at a different angle than the rest?) say you do not have Vortec heads. But Rick already confirmed that. Just wanted to make sure anyone else who read this would understand why.

 

[180shabah]

Re: Identifying Vortec heads???

Thanks everybody, I was pretty sure I had the old heads, just wanted to be sure.
DonS, the engine is the original(SN 0F781275) it only had 46 hrs when I bought it.