Can you guys lighten this subject for me because I thought I had vortecs on my car but I don't know how to tell the difference? The motor is a 1991 350 l98, I thought almost all tpi cars came with them.

 

As far as I am aware no third gen came with vortec's. If they did, the manifold from those cars would be sought after big time. Then we wouldn't have to buy the scoggin dickey mainfold.
Hope I didn't burst your bubble.

 

no you didn't but hey how much hp increase would I see If I bought a pair? .......And where could I find them? lol

 

Keep in mind that you need a new intake manifold to make the vortec heads fit our cars. There is an edelbrock one available a summit and the same one at SDPC.com About 400$. I've heard about 30+hp depending on the vortec's you get, porting, valves etc. Cam and heads go hand in hand. I won't be building my motor till next year. Maybe.

 

oh ok well i was going to put a summit cam in my car anyway do you think i can get both for like $1500 or less?

 

Seeing as how "Vortec" heads didn't come out until 1996, no third gens would have come with them... I see so many people think that their '87-'95 heads are vortec heads because the center intake manifold bolts are at a different angle... SOOOO many people think they have some special "Vortec" head, which is just a buzz-word anyway for fast-burn chambers and raised intake ports.. An easy way to identify Vortec heads is to count the number of intake manifold bolts that hold the manifold down... Vortec heads will have two bolts in each corner of the engine, all of them are perpendicular to the ground with the engine sitting in the car.. So if you have 8 bolts, and they're straight up and down, then it's probably vortec heads...

 

Well Vortec is gm branding. Not soo much a buzz word. a Vortec engine is quite different from a traditional SBC.

-- Joe

 

Well, I'd consider a Gen-II LT1 quite different from a traditional SBC, but not really a vortec engine.. Granted, the heads are good heads, but other than the induction system (which doesn't come into my equation, you can put many forms of induction on any engine), there's not a lot of primary differences other than the cylinder heads in a Vortec engine..

 

I have one apart at the shop out of a '98 1/2 ton I had. I know the oil pans are the same, timing covers are different. Internally I think the casting is a little different but I think the rotating assembly is the same.

-- Joe

 

so then how do the centerbolt valve covers come into play? That is what i have on my 88 camaro 350tpi. Does this mean I can buy a sbc cylinder head that does not have center bolt valve covers?

 

Kinda. Iron heads changed the intake pattern a little bit, the center bolts changed angle. Alum heads (vette) did not change. So if you get older heads OR vette heads you gotta slot the intake, or buy an aftermarket (slotted) intake.

Then there is also differences in the rockers, self aligning vs not, and associated pushrods for each. If you go with the older heads on a roller motor make sure you get the vette pushrods because they are hardened for use with guide plates. The old style harded pushrods wont be the right length.

-- Joe

 

if you remove your intake manifold the intake ports are larger that most others and the stamp number along the side below the valve cover on the manifold side, can be ran to see fore sure look you numbers up to make sure completely. As i knew it 4th gen were the cameos that had the vortecs maybe a few latter third gen ones had them i don't know, but you can get a set on eBay or a machine shop can mill some to fit your block, but i have the left side vortec head that will fit most or all 350's, it brand new, my step dad works and Delphi and made a calibration machine for Gm vortec heads and he got the head from work, if you pay for shipping and give me $75.00 obo, i would sell you it. a good source to find the other side is eBay, you can find good deals on just one or get a set, i am going to make a lamp out of it if not lol.

 

wow thanks, finally a forum that will answer my questions. Ok so let me get this straight.....I need to slot as in make the bolt holes longer? how does that affect the ports? If I was going to buy a new HSR manifold what would I buy to fit these headshttp://www.midwestmotorsportsinc.com/order_part.php?item=PPHEAD&line=MWM

 

if you get the vortec heads, you will need a manifold to fit it, you can't adapt your current intake manifold to fit (and if you could, after welding, machine work, it wouldn't be worth it). They were discussing modifying a iron-headed '87-'95 intake manifold (which involves slotting the center intake pairs so you can get the bolts in) to fit a traditional SBC pattern (12 bolts, all at 90* angles to the intake->head mating surface).

Those look like just standard SBC heads, so you'd get the regular 7540 (I think thats the PN for the standard) HSR.