low buck junk SBC

General engine tech -- Drag Racing to Circle Track

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dannobee
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Re: low buck junk SBC

Post by dannobee »

When I say "Vortec," I'm referring to the L31, vin code "R" engine with either 906 or 062 casting number cylinder heads, with 4 intake manifold bolts on each cylinder head. The others (other than the V6 that said "vortec" on the plastic valve covers), were not "vortec" but did have high vortex swirl flow heads, along with TBI. Those were designated L05, vin code "K" engines. They had that goofy ski jump in half of the intake port to introduce swirl into the mix.

The vortec heads would be a great upgrade, but they are limited to 0.480" lift before the retainer hits the valve guide. The 906 and 062 heads are pretty much all the same except for the 906 used in the 1ton (and HD) trucks, which had inconel exhaust seats.

One more thing regarding timing chain/gear set. Make sure that you degree in the cam, as they seemed to move the cam timing around to meet emissions. The replacement sets might have been all the same, but the production line sets were not.
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Re: low buck junk SBC

Post by turbo camino »

I know this is getting way off track, but, the Vortec branding was definitely used for the TBI/swirlport truck engines before the 1996 L30/L31 versions appeared. Vorted 305 & Vortec 350 before '96, Vortec 5000 & Vortec 5700 after. I and everybody else was using the Vortec name for them in the early '90s, we didn't invent it on our own.
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dannobee
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Re: low buck junk SBC

Post by dannobee »

What was the RPO on those vortec V8's, pre '96? V6, sure, the L35 vin code "W" CPI engine that had all of the injector poppet nozzle problems.

My memory might be slipping, but I don't remember any vortec V8's before 96.
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Re: low buck junk SBC

Post by rebelyell »

dannobee wrote: Sat Nov 23, 2019 11:57 pm Vortec heads had beehive springs with smaller retainers. And didn't have valve rotators.
OE Iron Vortec L31 heads have straight conventional springs but no dampers.
spring GM pn 10212811 ... 80 lbs on seat, retainer GM pn 10241744
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Re: low buck junk SBC

Post by rebelyell »

dannobee wrote: Sun Nov 24, 2019 3:31 pm What was the RPO on those vortec V8's, pre '96? V6, sure, the L35 vin code "W" CPI engine that had all of the injector poppet nozzle problems.

My memory might be slipping, but I don't remember any vortec V8's before 96.
5.0L L30, 5.7L L31 ... L31 is vin code R

afaik, V8 Vortec began 1996
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Re: low buck junk SBC

Post by turbo camino »

L03 & L05, in trucks, were called Vortec. I believe they were the first to use the name along with the TBI 4.3 of the same era. It didn't denote anything special or different from the same engines used in cars, it was just a truck badge-marketing thing. It wasn't pushed hard like in later years with fancy logo'd plastic covers and all that but before '96, if you said 'Vortec', everybody knew you meant a TBI truck motor. Where'd that name come from before '96 if not from GM?
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Re: low buck junk SBC

Post by dannobee »

turbo camino wrote: Sun Nov 24, 2019 6:19 pm L03 & L05, in trucks, were called Vortec. I believe they were the first to use the name along with the TBI 4.3 of the same era. It didn't denote anything special or different from the same engines used in cars, it was just a truck badge-marketing thing. It wasn't pushed hard like in later years with fancy logo'd plastic covers and all that but before '96, if you said 'Vortec', everybody knew you meant a TBI truck motor. Where'd that name come from before '96 if not from GM?

Do you have a pic of a vortec badge on an L03 or L05? I'd like to see one, because we never called them "vortec," although we did call the heads "swirl port heads." (Often disparagingly) The only Vortec designation that I've ever seen before 96 was on the L35 V6, starting in 92 (the plastic trim on the upper plenum or on the plastic valve covers). Internally, we'd refer to the L05 and L03's by the 8th digit of the vin, i.e., "it's an "M" motor, or "it's got a "K" motor in it." Likewise, we called the "Vortec" 5.7L an "R" engine. In nascar the "vortec" designation in the rule book referred to only the L31 head. Anything earlier was just a regular smallblock chevy head.
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Re: low buck junk SBC

Post by dannobee »

rebelyell wrote: Sun Nov 24, 2019 6:13 pm OE Iron Vortec L31 heads have straight conventional springs but no dampers.
spring GM pn 10212811 ... 80 lbs on seat, retainer GM pn 10241744
You're right, I must have been thinking about the LS engines.
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Re: low buck junk SBC

Post by rebelyell »

In the years before name "Vortec" began, did GM refer to their TBI "swirl port" tech by the name Vortex?
I seem to recall valve covers etc with Vortex (with an X).
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Re: low buck junk SBC

Post by 1980RS »

turbo camino wrote: Sun Nov 24, 2019 5:46 am
1980RS wrote: Sat Nov 23, 2019 9:42 pm The B-body cam is the same as the 96-97 Camaro LT4 cam, next step up was the Hot Cam.
Only the 'baby LT1' L99 used the cam you mention, the other B-body LT1s used the 191/196.
Interesting as when I worked at Buick we pulled the cam out of an LT1 in the car. I speced in the cam, the lift and duration was the same as the LT4 cam. I gave it to my buddy with his Camaro V8 and he really liked the car better.
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Re: low buck junk SBC

Post by 1980RS »

dannobee wrote: Sun Nov 24, 2019 8:45 am When I say "Vortec," I'm referring to the L31, vin code "R" engine with either 906 or 062 casting number cylinder heads, with 4 intake manifold bolts on each cylinder head. The others (other than the V6 that said "vortec" on the plastic valve covers), were not "vortec" but did have high vortex swirl flow heads, along with TBI. Those were designated L05, vin code "K" engines. They had that goofy ski jump in half of the intake port to introduce swirl into the mix.

The vortec heads would be a great upgrade, but they are limited to 0.480" lift before the retainer hits the valve guide. The 906 and 062 heads are pretty much all the same except for the 906 used in the 1ton (and HD) trucks, which had inconel exhaust seats.

One more thing regarding timing chain/gear set. Make sure that you degree in the cam, as they seemed to move the cam timing around to meet emissions. The replacement sets might have been all the same, but the production line sets were not.
I just did some Vortecs and mine had .410 clearance when I checked them. I had to cut this set as there was no cam other than stock that would work with that.
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Re: low buck junk SBC

Post by turbo camino »

dannobee wrote: Sun Nov 24, 2019 7:01 pm Do you have a pic of a vortec badge on an L03 or L05? I'd like to see one, because we never called them "vortec," although we did call the heads "swirl port heads." (Often disparagingly) The only Vortec designation that I've ever seen before 96 was on the L35 V6, starting in 92 (the plastic trim on the upper plenum or on the plastic valve covers). Internally, we'd refer to the L05 and L03's by the 8th digit of the vin, i.e., "it's an "M" motor, or "it's got a "K" motor in it." Likewise, we called the "Vortec" 5.7L an "R" engine. In nascar the "vortec" designation in the rule book referred to only the L31 head. Anything earlier was just a regular smallblock chevy head.
No, like I said, pre-'96 they weren't slapping logos all over everything like in later years. And I have a 2006 Envoy that most definitely has a 'Vortec 5300' in it, but no Vortec badging anywhere to be found (I think, but not positive, that the same RPO installed in a pickup DOES get a Vortec-branded plastic cover). If I tried getting parts info about it by asking about a 'Vortec motor' you'd think I'd lost my marbles. If I said LH6, we'd both know instantly what I meant. Because somehow it's turned into a thing where if somebody says 'Vortec' with no other qualifications, everybody is supposed to know they are talking about a '96-'99 L31. Vortec really should be meaningless, given the many dozens of different unrelated engines it's been applied to. It was used before the L31, and after the L31, yet somehow it only stuck to that one single engine...
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turbo camino
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Re: low buck junk SBC

Post by turbo camino »

rebelyell wrote: Sun Nov 24, 2019 7:16 pm In the years before name "Vortec" began, did GM refer to their TBI "swirl port" tech by the name Vortex?
I seem to recall valve covers etc with Vortex (with an X).
GM called those intake ports 'vortex', no capital, and applied the marketing name 'Vortec' to those engines with 'vortex' ports. It's fairly common to see them mixed together and confused in internet-land.
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Re: low buck junk SBC

Post by HotRod H269 »

This thread has brought back a ton of old memories! I started racing my 81 Malibu street car back 1989 when I turned 16. It started out as a 10.40 car in the 1/8 . I had many different combinations in that car and got it down to 7.70s with a 3.42 gear but it sure was hard on that 7.5 10 bolt!! Lol...
I won my first race in it going 9.80s after a gear change. I drove it everyday to school and drove it to the track. It sure was alot of fun back then! Hope your son has alot of good luck with it!
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Re: low buck junk SBC

Post by CGT »

I seem to remember a tbi 4.3 "Z" in S and T series being referred to as "vortec"....but not the lo3 and lo5 "K" and "M" engines.....could be wrong ....4.3 W prior to 96 for sure....vortec name has been thrown around at GM for a long time.
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