VINTAGE SS ALUMINUM SB INTAKE

Any idea what was a hot SB 4 bbl intake from later 70's-80's. I'm thinking Port O Sonic or Eddy intakes(TM-1) that would have been used in Super Stock Class? Thanks

Not super fast but I ran 11.82 in my street strip 1970 (340) duster in the late 1970’s with a Port O Sonic out of the box.

Or a Holley Strip Dominator.I think the Edelbrock Victor 340 came out later, but might fit the bill too?

For what it is worth I went to a Direct Connection seminar at Wise Speed shop in St. Louis in the late 70's Tom Hoover, Lee Shepard, and some guys from Mancini's were there, the question was asked about intakes for street & strip, Edelbrock LD-340 was their pick then. It was mentioned that it made more HP than several single plane intakes available at the time. They also said the factory cast iron intake for 340's with a thermoquad was almost as good as any aftermarket intake at that time.
Bought my blue mopar bible then, still git it.

My recollection was it was the Port-o-Sonic with lots of modifications, external as well as internal.

However that was a long time ago.

I ran a 340 with a Offy intake with 2 inch spacer and it had popsicle sticks epoxied in. In a 70 Cuda with a 904 it ran mid 11's in the 80's.

I went from a stock AVS intake to a Strip Dominator and picked up a solid .3 in the heat of the summer.

My ex-Hamburger SS/IA 340 Duster ran the Port-O-Sonic intake back in the day, apparently in its original combo.
When I got the car, it had a ported/polished Holley Strip Dominator on it, which appears quite similar to me.
Whether that was a later iteration of the car, or done in between by someone, I don't know.
The car was claimed to be the first 340 in the 10s - at one point 10.90 on an 11.08 index - and his deal was holding class records.
I went low-10s with the SD at 368" with the car - plugs always looked even, no lean/rich variation.
The car never saw street use, which of course is a different world, but was very responsive on return roads, FWIW.

I don't think the Portosonic was available when he first campaigned the 71 SS/IA car. I was in the process of building a SS 340 ebody and had bought a bunch of parts from both Hamburger and Cecil Yother. Ed told me to use the LD340 for a stick car and the iron thermoquad intake for an auto. I ended up not finishing that project because he told me that a 1970 Avs would not be competitive. I didn't want to start over with a 71 car so it became a street car. As a street car I tested just about every intake that was available at the time and ended up putting the iron back on and selling most of the others. I did keep the LD340 on the shelf for a while. This was before the Holley SD came out and maybe before the Offy. A few years later Herb M. tried to talk me into putting W2 heads and a Holley Strip Dominator on it but by then I was done with small blocks.

The Portosonic info came from period articles on the car.
There's another article on another of the early cars that shows the engine & compartment, but I no longer have it - gave it to the car's new owner.
May have been an old SS&DI issue, the car was white & as I recall a darker color was showing through in spots underhood, probably from gas spills.
I recall the LD340 being the hot tip for street/strip.
The "1971" car is actually a '70 - jit got the updated Sharktooth grille so he could run the T-quad.
Funny you should also mention Cecil; been friends with him for decades & worked for him for a bit.

I had forgotten about the year change. That's probably why he was suggesting that I do the same but its a little more difficult on a ebody
I bought some parts from Yother probably at least 50 years ago.

The LD-340 to this day is regarded as an excellent high performance dual plane manifold- decades before the intro of the Performer RPM. But because of this the pricing has gone insane on the LD-340 units. Looks like the Port O Sonic single plane Offenhauser was their first array into legit scientifically proven single plane design for high RPM use. The design Offenhauser is known for is their split down the middle divided plenum single plane intake manifolds which seems to be the standard from the 50s and early early 1960s.

Everyone always brings up the "popsicle stick" Port-O-Sonic as the best intake for its time because there was a limited number of Mopar intakes available. While true, the distinction between Thermoquad and Holley square bore use isn't mentioned unless the topic centers around the Super Stock class. The Thermoquad was the only "legal" carb for SS, thus the need for a legal modification because of the spread bore. Have there been any tests of a "stock" Port-O-Sonic with a square bore Holley compared to the LD340 and other options? (Rarely heard anything positive about other single plane intakes like the original Torker & Tarantula.) Just wanted to note that the Thermoquad popsicle stick mod couldn't possibly work well in a square bore carb application.

I see pittsburghracer has a positive view of a stock Port-O-Sonic!

I used the LD340 on the street and early bracket racing years. The Holley Strip Dominator provided great results with my bracket W-2 engines and later IHRA Crate Motor Stock class. The Edelbrock Victor had a deeper plenum and didn't seem to work as well in my applications. (7,000 rpm max.) Other racers in my classes didn't find a benefit with the Super Victor as well.

Of course, jetting will be a factor in any comparisons. You can't simply swap intakes and take for granted that fuel distribution remains the same.


Didn't Hamburger make adapters to put small block Chevy intakes on Mopar small blocks in the Super Stock or Modified classes in the early years?

Dad and I ran a 71 340 Super Stock in the late 70's, the Holley Strip Dominator was a solid tenth better than the 2100. LD-340,, and Offy/Hamburger Port-O-Sonic. The Edelbrock Victor wasn't out at the time, but is on a Super Stock 340 I built recently

Not including the W2 stuff, I thought the Holley Strip Dominator and Edelbrock Tarantula TM5 where the hot small block intakes of the late 70s. When Ebrock dumped the TM series for the Victors, that was the hot set up in the 80s.

The original Torker & Tarantula were brought out by Edelbrock early on as their higher rpm intakes. They may have been "hot" but there were few others to choose from. It's almost like they slapped the Chevy versions onto Mopar flanges. As noted by some, the Holley Strip Dominator was a huge improvement. Victors came out after the Strip Dominators but how it compares depends on the application, usually favoring higher rpm regardless of their "advertised range". There were some LD340's modified as well as cast for W-2 heads in the '70's. But the need was there for a single plane. I'm not sure but the LA Strip Dominator may have come out after the W-2 version. They worked well enough for Mopar to make, what look like,
copies of the Holley for their M-1 series.

I dont think the TM5 on a stroker is that bad. Wasnt it the 1st single plane offered?

Here is a pic of the glass unit from the article.

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LD340 worked the best for me back in the day on the street/strip. I had a holley strip dominator on a 340 and it ran worse for my combo.

Herb McCandless states in his YouTube Autobiography that he developed a W2 Single plane in the Early 70's after he quit racing Pro Stock during the Hemi/Weight break debacles. He said he Developed it for Edelbrock and it was supposed to become the Victor 340...and Apparently it did...But it Became the SB Chevy Victor FIRST!! Edelbrock stole the design for the Chevy and then it became the Mopar.

The Victor 340 (as anybody who runs one knows) has super thick runner dividers, but you can really port the heck out of them. I think maybe Edelbrock fattened the dividers because what they copied made for too much cross section for a typical "hot Street" small block of the day. The reduced the ports by thickening the runners...figuring racers were going to port them anyway. Just my "theory, I can;t imagine why else they would make the runners so chunky otherwise.

Maybe Herb Jr can ask Sr to elaborate but I believe Edelbrock Herbs contention that copied/stole/borrowed Herbs design....because from a short distance you can hardly tell a Victor SB Mopar/Victor Jr SB Chevy apart.

I couldn't get the TM! to make consistent power thru the RPM range. I highly modified the runners with not much success. A tapered/divided spacer from Wilson made it perform much better but still not close to the M1 but that's not period correct.