Older 2 barrel Intake Manifolds

[64Avanti]

I ran across something that looks strange to me. The parts book list manifold part number 534854 for the 1954 V8. Of course that engine had the small valves and ports. However the same part number is listed for 1955-1957 with 2 barrel carb and that engine would have course had the larger head ports. So it looks like they used the small port intake with the larger port heads. Anyway never new that before.

[Mike Van Veghten]

May have been a method to get rid of a large quantity of old stock, rather than toss it for scrap or send it back for remelting.

Mike

[64Avanti]

May have been a method to get rid of a large quantity of old stock, rather than toss it for scrap or send it back for remelting.

Mike

Mike that is a lot of old stock. That intake came out in 1954 and was then used for 3 model years on all 2 barrel V8s.

[HOXXOH]

I ran across something that looks strange to me. The parts book list manifold part number 534854 for the 1954 V8. Of course that engine had the small valves and ports. However the same part number is listed for 1955-1957 with 2 barrel carb and that engine would have course had the larger head ports. So it looks like they used the small port intake with the larger port heads. Anyway never new that before.

That makes me question if the part number for the '54 intake gaskets was 530266 like the '51-'52 engine used? It's been a long time ago that I used a '52 manifold on heads from an unknown year ('58?) 289 on the .060 overbored 232 that I raced. I don't remember if I port matched that intake to the heads, or what gasket I used. Just curious to see if the port size on the hi-rise (more vertical runner) manifold used the same gasket as the flatter runner low-rise manifold.

[StudeRich]

The answer is as usual quite simple, the ONLY Ports that were enlarged for the 224, 259, 289 were the Exhaust, the Intake size never changed, same Gaskets, same Intake Manifold "Size" for '51-'54 "232" and ALL the rest.

Of course the "Other" characteristics of the Intakes were updated later like, 1959 on the Low Rise vs '51 to '58 High Rise.

[64Avanti]

Thanks Rich. The only older than 55 engine I ever had was immediately replace with a 289 many years ago so I never even looked at the heads on the 232. I learned something today that I never knew. It still happens once in a while! I just looked and the part number for the inlet gaskets is the same all the way up to 64 except the ones for the R2 engines that restricted the heat riser crossover flow.

[PackardV8]

The answer is as usual quite simple, the ONLY Ports that were enlarged for the 224, 259, 289 were the Exhaust, the Intake size never changed,

The valve sizes certainly changed on both intake and exhaust:

Intake valve diameter:
232” – 1-13/32" = 1.40625”
224”/259”/289” - 1-21/32 = 1.65625”
R3/R4 - 1-7/8" = 1.875”

Exhaust valve diameter:
232” – 1-9/32” = 1.28125”
224”/259”/289” - 1-17/32 = 1.53125”
R3/R4 - 1-5/8" = 1.625"

jack vines

[StudeRich]

Remember that we were only talking Intake Manifold PORT size and matching Cyl. Head Inlet Ports, between 232 and the Rest, that's all.

[DEEPNHOCK]

Generically speaking......
There can actually be an advantage to having the intake manifold outlet port slightly smaller than the intake runner on the head.
Pulse reversion waves can flow backwards all the way to the carb butterflies. Having a little reverse 'step' in the runner can help disrupt those pulses. Ok, ok.... Racer stuff aside.
Studebaker OE never considered that. Just a cost analysis of how much any head/manifold update/upgrade would cost.
And to add...
I have bored out the early 2bbl throttle bores to accept a 650cfm Rochester 2bbl carb (including the governor spacer block).
The later cast iron 2bbl intake still outflowed the early intake.

[PackardV8]

The later cast iron 2bbl intake still outflowed the early intake.

Good info, Jeff and thanks for sharing. Looking at the early 2-bbl intake, it's easy to make the assumption it would flow better; however I learned long ago never trust the eyeball dyno or the butt dyno.

jack vines

[firestoper 25]

Excellent points as usual Mr. V And it has been decades since I had my butt dyno calibration inspected . It seems to be dragging a lot lately.

[bensherb]

I love it John!

I like that you bring up reversion Jeff. Something most never consider.

[bezhawk]

On extreme engine builds, I put my flexible bore scope camera down the intake and make notes as to where to port it so there is a smooth transition from the manifold to the head.

[HOXXOH]

Generically speaking......
There can actually be an advantage to having the intake manifold outlet port slightly smaller than the intake runner on the head.
Pulse reversion waves can flow backwards all the way to the carb butterflies. Having a little reverse 'step' in the runner can help disrupt those pulses. Ok, ok.... Racer stuff aside.
Studebaker OE never considered that. Just a cost analysis of how much any head/manifold update/upgrade would cost.
And to add...
I have bored out the early 2bbl throttle bores to accept a 650cfm Rochester 2bbl carb (including the governor spacer block).
The later cast iron 2bbl intake still outflowed the early intake.

What car used that 650cfm Rochester carb? I thought 450 cfm was the largest.

In the late '60's, I bought a 2GC from a place in Washington or Oregon that had the outside of the venturi bores epoxyed, which allowed them to bore it out to the same 1.68 dia. as the throttle base. They claimed it flowed 700cfm. I machined about 1/4" off the top of my '52 manifold to get a larger surface area than the OEM Stromberg used and then drilled/tapped the bolt pattern and bored it to match the 2GC base. I had no flow bench to test it, but the car ran fast enough to set AHRA World records.
A couple years later, I built a box to enclose the carb, so I could use a VS-57 blower.

[DEEPNHOCK]

Maybe it was 500 cfm...
The circle track stock car guys that run the 2bbl classes have had carb guys hot rod the 2gc to flow more.
I don't know much about them other than that.