SBC Intake Manifolds: Creating Another List.

[skinny z]

Stock Vortec must be half a chance.

maxresdefault.jpg

It's difficult to tell from the pictures so I'll ask how long those runners are from the plenum to the port face?

[Tom68]

Stock Vortec must be half a chance.

maxresdefault.jpg

It's difficult to tell from the pictures so I'll ask how long those runners are from the plenum to the port face?

Dunno, more even lengths than a single plane though.

s-l1600 (13).jpg

s-l1600 (1).jpg

I think this Vortec has the stock manifold ? 550 lift cam springs and retainers. Injection plumbing would need a cleanup to get out of the way of the runners.

https://www.youtube.com/watch?v=-X1TAF0 ... ussCoffell

550 lift springs and retainers Vortec.jpg

[Tom68]

Speaking of which, what's out there besides the usual suspects from Holley and Edelbrock?
There's also Speedmaster.

One I bought back in 2014. Procomp, lower runners are pretty small.

20140825_165241.jpg


20211228_113706.jpg

Procomp.jpg

Is that ProComp a single plane? When you mentioned lower runners, I thought no.

Yer nah, sorry dual plane.

[ChopperScott]

The "mini" SBC. This was the lower intake with upgraded spider injection on my Vortec 4.3 in a ZR2 Blazer I had...

IMG_3311.JPG

[F-BIRD'88]

All the other vortec head single planes are quite tall carb height..

Speaking of which, what's out there besides the usual suspects from Holley and Edelbrock?
There's also Speedmaster.

I have the Professional Products Crosswind (vortec) dual plane air gap intake on my 406.. Works fine. no mods

The Speedmaster79 intakes seem to be copies of the PP stuff.(Typhoon, Crosswind, Hurricane)

The most recent Weiand stuff "Air Strike" looks good to me.

[skinny z]

The "mini" SBC. This was the lower intake with upgraded spider injection on my Vortec 4.3 in a ZR2 Blazer I had...

IMG_3311.JPG

What do you reckon that intake runner length is? How would it compare to a single plane? Looks nice and straight.

[F-BIRD'88]

Stock Vortec must be half a chance.

maxresdefault.jpg

It's difficult to tell from the pictures so I'll ask how long those runners are from the plenum to the port face?

Dunno, more even lengths than a single plane though.



s-l1600 (13).jpg


s-l1600 (1).jpg


I think this Vortec has the stock manifold ? 550 lift cam springs and retainers. Injection plumbing would need a cleanup to get out of the way of the runners.

https://www.youtube.com/watch?v=-X1TAF0 ... ussCoffell

550 lift springs and retainers Vortec.jpg

I have looked and looked and looked at this OEM L-31 Vortec EFI lower intake for adaption to carbs... with a added custom carb plenum top.. Lots of fuel distribution issues with carbs on. Would require a lot of sorting out but could be good on the street.
Some potential as a blower intake for a vortec engine.
It will take work either way. "Cross Ram"

Mounting 4 holley 2 bbls right over the runner entrances on a custom plenum top might be fun.
Or possible mount 2x AVS 650's in a twisted orientation to optimize the port fuel distribution.
There is a mercruiser marine version thst has a much flatter cleaner looking floor contour.
The floor is going to need lots of optimizing
3x2 Tri Power induction might be fun. (Holley, Rochester)

You'll have the only one on cruise nights.

[skinny z]

It's difficult to tell from the pictures so I'll ask how long those runners are from the plenum to the port face?

Dunno, more even lengths than a single plane though.



s-l1600 (13).jpg


s-l1600 (1).jpg


I think this Vortec has the stock manifold ? 550 lift cam springs and retainers. Injection plumbing would need a cleanup to get out of the way of the runners.

https://www.youtube.com/watch?v=-X1TAF0 ... ussCoffell

550 lift springs and retainers Vortec.jpg

I have looked and looked and looked at this OEM L-31 Vortec EFI lower intake for adaption to carbs... with a added custom carb plenum top.. Lots of fuel distribution issues with carbs on. Would require a lot of sorting out but could be good on the street.
Some potential as a blower intake for a vortec engine.
It will take work either way. "Cross Ram"

Mounting 4 holley 2 bbls right over the runner entrances on a custom plenum top might be fun.
You'll have the only one on cruise nights.

I just knew you had a scheme for duals on that!

[Tom68]

Pity the marine version with external injectors is cast iron.

inside.jpg

[F-BIRD'88]

Dunno, more even lengths than a single plane though.



s-l1600 (13).jpg


s-l1600 (1).jpg


I think this Vortec has the stock manifold ? 550 lift cam springs and retainers. Injection plumbing would need a cleanup to get out of the way of the runners.

https://www.youtube.com/watch?v=-X1TAF0 ... ussCoffell

550 lift springs and retainers Vortec.jpg

I have looked and looked and looked at this OEM L-31 Vortec EFI lower intake for adaption to carbs... with a added custom carb plenum top.. Lots of fuel distribution issues with carbs on. Would require a lot of sorting out but could be good on the street.
Some potential as a blower intake for a vortec engine.
It will take work either way. "Cross Ram"

Mounting 4 holley 2 bbls right over the runner entrances on a custom plenum top might be fun.
You'll have the only one on cruise nights.

I just knew you had a scheme for duals on that!

I have a SCHEME for 2X4's on everything. ha ha ha

[Tom68]

I have looked and looked and looked at this OEM L-31 Vortec EFI lower intake for adaption to carbs... with a added custom carb plenum top.. Lots of fuel distribution issues with carbs on. Would require a lot of sorting out but could be good on the street.
Some potential as a blower intake for a vortec engine.
It will take work either way. "Cross Ram"

Mounting 4 holley 2 bbls right over the runner entrances on a custom plenum top might be fun.
Or possible mount 2x AVS 650's in a twisted orientation to optimize the port fuel distribution.
There is a mercruiser marine version thst has a much flatter cleaner looking floor contour.
The floor is going to need lots of optimizing
3x2 Tri Power induction might be fun. (Holley, Rochester)

You'll have the only one on cruise nights.

You'd think 5 and 7 would need more plenum room around them even for port injected let alone carbys.

[F-BIRD'88]

I have looked and looked and looked at this OEM L-31 Vortec EFI lower intake for adaption to carbs... with a added custom carb plenum top.. Lots of fuel distribution issues with carbs on. Would require a lot of sorting out but could be good on the street.
Some potential as a blower intake for a vortec engine.
It will take work either way. "Cross Ram"

Mounting 4 holley 2 bbls right over the runner entrances on a custom plenum top might be fun.
Or possible mount 2x AVS 650's in a twisted orientation to optimize the port fuel distribution.
There is a mercruiser marine version thst has a much flatter cleaner looking floor contour.
The floor is going to need lots of optimizing
3x2 Tri Power induction might be fun. (Holley, Rochester)

You'll have the only one on cruise nights.

You'd think 5 and 7 would need more plenum room around them even for port injected let alone carbys.

Yes lots of issues.. EFI with dry runners/ plenum gets away with lots of evils. Cross rams are always a challenge. I would not run out and buy this but if one fell out of the sky and someone had way too much time on their hands......

[ChopperScott]

The "mini" SBC. This was the lower intake with upgraded spider injection on my Vortec 4.3 in a ZR2 Blazer I had...

IMG_3311.JPG

What do you reckon that intake runner length is? How would it compare to a single plane? Looks nice and straight.

That engine ran well. It was a GM performance engine, but not aggressive enough to handle a single plane.

[Tom68]

Now here's a marine one to keep an eye out for.

459423_356085397773748_90710916_o.jpg

Vortec Marine.jpg

[F-BIRD'88]

Now here's a marine one to keep an eye out for.

459423_356085397773748_90710916_o.jpg

Vortec Marine.jpg

Yes with. a custom carb top it could be fun on a street strip car.
This marine intake manifold lower was used on the Mercruiser Ski boat scorpion/black scorpion series engines.. There are 2 versions .1 is for the older pre 1996 engines that used the #083/#217 sbc head castings.
the other. 96+ is for the engines that had the L-31 Vortec heads #062/#906. I belive the marine engines got the #906 vortec heads.

It is designed to make good midrange up torque and power in the rpm range a street strip engine runs.
Room for creative porting. Lots of potential for custom creativity of a custom carb plenum top for various street carb schemes. 2x4. 3x2. etc.
Even forced induction.
Edelbrock was selling off all their old stock of these a few years ago.. The price was cheap. They all went fast.
I believe some of the specialty marine engines used this EFI base as well. Tons of potential.