Vortec heads??

[GMPartsGuy]

OK guys, here goes:

I have a couple of questions regarding the terminology used for the Vortec heads. I already did a search on "vortec" and came up with over 225 results. I read about 75 of them until it felt like my eyeballs were going to explode. Unfortunately I didn't find the answers I was looking for.

I see the terms "Vortec" and "L35" being used as if they're different. From my understanding, when GM went to the 4.3W engine in 92 (the "Vortec"), it had the RPO code L35. And even when there were major changes to the heads in '96 (different intake bolt pattern, raised runners), GM still uses the L35 code for them, and still calls them Vortecs. My question is, what heads are you referring to when you use each of the terms?

I see that most of the people here are using the '96+ heads. Obviously, it's a lot of work, and that's why I'm apprehensive about trying the conversion. Now correct me if I'm wrong, but didn't GM go to the killer combustion chamber design in '92 while keeping the runner location and manifold bolt pattern the same as our trucks? If so, why not just use the 92-95 Vortec heads instead of going through all the trouble of trying to fit the '96+ heads on?

Also--when you reply, try to take it easy on me. I'm a parts guy....not an engineer.

Harold
92 Ty, bone stock...mostly

 

[CLONE]

When people here say Vortec they are usually referring to the 96+ heads.

The L-35 heads have the same sucky combustion chambers as the stock sy/ty heads. They have the chamfer removed from the siamesed intake ports and somewhat better intake and exhaust flow compared to stock.

The 96+ heads have awesome combustion chambers and great ports.

As for the term vortec, my old 1989 Chevy Astro van's window sticker referred to the engine as a "vortec" so it's not a great way to describe anything GM.

 

[smeagol]

In the Syty crowd, the 96+ heads are referred to as Vortec. Really, they are engine code LF6, X motor. Very much like the raised runner SBC "Vortec" cast iron heads.

The L35 heads have been the same (or relatively so) since 93ish. L35 motor, W code.

It's a huge confusion, thanks to GM, and calling everything Vortec.

Even the new motors are Vortec, WTF. I have Vortec exhaust, and Vortec tail lights. I know i know, the stance with the intake port design, well that definition sucks.

FWIW, I believe the L35 DID have a gasket surface between the siamesed intake ports. I need to refer to some pictures.

 

[myclone]

Re: Vortec heads??

OK guys, here goes:

I have a couple of questions regarding the terminology used for the Vortec heads. I already did a search on "vortec" and came up with over 225 results. I read about 75 of them until it felt like my eyeballs were going to explode. Unfortunately I didn't find the answers I was looking for.

I see the terms "Vortec" and "L35" being used as if they're different. From my understanding, when GM went to the 4.3W engine in 92 (the "Vortec"), it had the RPO code L35. And even when there were major changes to the heads in '96 (different intake bolt pattern, raised runners), GM still uses the L35 code for them, and still calls them Vortecs. My question is, what heads are you referring to when you use each of the terms?

Im no expert on the subject but know enough to possibly get you started. Around here the terms Vortec usually mean the 96 and up heads and L35 usually means the ~92 to 95 heads. Although possibly the wrong name as far as GM is concearned it seems to work when communicating amongst ourselves.

I see that most of the people here are using the '96+ heads. Obviously, it's a lot of work, and that's why I'm apprehensive about trying the conversion. Now correct me if I'm wrong, but didn't GM go to the killer combustion chamber design in '92 while keeping the runner location and manifold bolt pattern the same as our trucks? If so, why not just use the 92-95 Vortec heads instead of going through all the trouble of trying to fit the '96+ heads on?

Also--when you reply, try to take it easy on me. I'm a parts guy....not an engineer.

Harold
92 Ty, bone stock...mostly

Im not exactly sure when GM went to the "good" combustion chamber but as far as I know the L35s of ~92 through ~95 have a slightly better than stock port configuration but still have the crappy old style combustion chamber. The 96+ "vortec" heads not only have decent ports but also a better combustion chamber design.

Some ppl do, in fact, use what we call the L35s as they are a moderate perf gain over the stock heads and are a bolt on where as ppl who are going for a more radical build will do the needed mods to get the 96+ vortecs to work. Its just a matter of how much money you want to spend and your performance goal as to which heads to use.

So youre a GM parts guy huh? Weeeeeelllllll. Whadya know.. I/we could prolly use your assistance in tracking down a part # for the 4300 marine engine rolled fillet crank should you feel the urge or run outta things to look up :wink:

Welcome BTW

 

[CLONE]

FWIW, I believe the L35 DID have a gasket surface between the siamesed intake ports. I need to refer to some pictures.

They do. I don't need to look at any pics, I have the images burned into my long term memory storage banks. Stock heads do not have a gasket surface between the siamesed intake ports, they are chamfered for the lack of a better term. 96+ also have a gasket surface like the l-35's.

My Syclone came equipped with a vortec transmission, did your's?

 

[Dealboy]

i see you can use the 96 and up heads but will the 96 up block work also and if it does is there any benefit?

 

[GMPartsGuy]

You guys are a total crack-up! But I do understand what you mean by the way GM uses the term "Vortec" as a blanket to describe nearly everything in the entire GM lineup. Of course, nobody asked me, but I personally think GM started using the term "Vortec" because of the reputation that Vortech superchargers had made in the automotive world. People hear the word Vortech and automatically think of horsepower. The fact that GM decided to drop one letter so they wouldn't get in trouble is chickenshit. BUT---that's neither here nor there.

Anyway, thank for sorting that out for me. Clear as mud.

Oh--and as far as getting the part number for that sweet rolled fillet marine crank, good luck. GM is incredibly tight-lipped about information and part numbers regarding marine parts. We tried to get my boss the part number for a set of marine Vortec small-block heads (much thicker casting, and they accomodate valves with enourmous stems for sustained high RPM) from the Performance division of GM ParTech (GM parts tech assistance)....you know what they said? That they couldn't give us ANY of that information because of confidentiality contracts between GM and Mercury Marine. He also told me that even if I DID get a hold of the part number, and I tried to order it, the order would immediately cancel since we're an auto dealer, and it's a marine part. So there's the basic scoop. SUCKS. :evil:


By the way...does anybody have the part number for the gearshift knob with "Vortec" embossed in the top? I'm having trouble finding it and I think that would be KEWL

Harold
92 Ty bone stock...mostly

 

[CLONE]

i see you can use the 96 and up heads but will the 96 up block work also and if it does is there any benefit?

The engine will run smoother, but that block is weaker so you run the risk of creating a boat anchor.

 

[ericguy320]

i have a vortec glove box in my blazer


is there any differance in head design between the 96+ moters, not sure of the moter code x,v,y somthing there were differant hp rating 190 and 200 i think it was the s-10 and the astro and full size truck. just wanted to know cause i come acrosed them at work a lot and want to know wich one i should use.

 

[93ty475]

but I personally think GM started using the term "Vortec" because of the reputation that Vortech superchargers had made in the automotive world. People hear the word Vortech and automatically think of horsepower.

thought crossed my mind as well...I have to admit, they were alot more powerful than the previous engines...


servando