Early 383 RB manifold vs. 440 manifold

I've got a bit of a Frankenstein engine - it is a 1972 440 block, but it has a 1959 383 4-bbl manifold on it. These very early 383 manifolds were actually for a 383 RB block (only in 1959 & 1960 I believe), so it fits on this 440 block quite nicely without requiring gaskets / spacers.

So here is my question: does anyone know whether the 383 manifold will flow air "slower" on the 440 block, than a stock 440 manifold? I am assuming the 383 manifold probably has narrower passages than a stock 440 manifold (can anyone confirm?). So that could mean either air flows faster due to the narrower passages & venturi effect.....or it could flow slower due to narrower passages. Or it might not make much of a difference at all.

I'm not building a high-performance engine, but if a stock 440 would perform a little better than a 383 manifold, I might make the switch.

Thanks much - Wade

Welcome aboard, Wade! I know a little about the early engines and I would not use that manifold on a 440 for reasons you voiced, plus the fact that the intakes really made a giant leap by 1968 and flow MUCH better than any of the earlier intakes. You can buy a stock 68-72 intake for under $50 that would work much better than an earlier intake.

Man, just because of the weight and ease of handling on install, etc, I would go anything alum, plus all the other advantages.

I wonder about the carb mounting pad, if the holes are too small to fit, say, a 440's AVS or Holley.
Would be interesting to see any design changes, like the runners, as well as port sizing.

I have a 2 brl intake for one of those somewhere

Thanks guys, I think will go for a later-model 440 intake. My father-in-law has a 1972 intake, I'll ask a follow-on question about it in the next thread. Wade

I would really be surprised if the 59/60 intake wasn't a very low rise intake with curved passages to make up for the low riser. Under hood clearance on the 57-60 model cars was a premium, most had the air cleaners set to the side to allow the hoods to close.
Having a high rise intake with pretty straight passages towards the heads would be a huge improvement on air flow. Gene

Yes it is a low rise with small Throttle bores. The small ports will make the air flow faster. Not a bad thing depending on the cam, rear gears and use desired, which you never told us about.

This intake will make the car slower compared to something else. But those early engines had compression, closed chamber heads, small cams and carb CFM. Very good throttle response and low end, but petered out quickly when RPM’s rise.

2806178 intake was used 1967-1969 on ALL 440 engines. Works real good.

BROOM that turd out and get a Streetmaster or SP2P...

NO.NO.never use those intakes on a 440.
Build a smaller motor if you want gas mileage
The early, pre 1967 BB Mopars with 4 barrel carbs had the small AFB bolt pattern and small air cleaner tops so the later AVS and standard 4150 Holley won't fit on those intakes All the production single 4 barrel intakes for the 413,426W and non HP 440 motors where horrible on air flow and carb size

sea Bee .... ... bite Mee ! ... you ole ...

WHY are you such a hater on these intakes ?

splain yourself or forever hold yur

If you are looking for any kind of performance, using those intakes is like pi$$ing through a straw.

MAYBE using the SP yes ... but the Streetmaster no.

DEPENDS on your needs and application

Have you ever used a SP2P ? Or help someone change to one?
Good manifolds stay in production for many years, neither of those two you mention did

sea Bee .... no and YES ... but I planned on running one meself on that 413 motorhomey! ... I did run a Street on it initially because the carb on it was junk.

I helped a bud with a 69 Imperial 4 door with SP and s TQ ! ... driving it smoothly netted him almost 21mpg with a 27 or 29 gear

NOT IN production for a ton of years ? .... true - it was during the gas crunch and that passed. BUT LOTS of good intakes have stopped ... best perfect example - the Helley Street Dom 440

But AGAIN ... why are you a hater ?

I know people who bought and used both of those intakes and regretted it They weren't as good as a stock intake so if I can help some other people avoid making that mistake why not

If your peeps were looking for HIGH drag strip PERFORMANCE from either of those intakes ... I would agree that those parts are IN FACT a bad choice... especially an SP2P.

But those intakes were never designed for that HP application.

I called Eddy some years ago about both those intakes. From what I digested from the convo WAS ....

SP2P ... better fuel mileage with better low rpm grunt AND be able to EZ usage of a TQ carb.

Streetmaster.... a much better mid range intake - THAN A STOCK IRON INTAKE - with an EZ adapt of a TQ carb.

In my experience and knowledge of others - EXCEPT from one guy from Bend Oregon- .....

Mission Accomplished

hey there OP, i am having 383 manifold and i have a few questions about it. what you've decided so far? https://suppsforlife.to/aromasin-for-sale/. how it goes? thanks

If you want to hear other opinions, troubles and experiences with SP2P intakes look here

https://board.moparts.org/ubbthreads/ubbthreads.php/topics/2740759/1.html

PROBLEMS with a SP2P? ... would only be the MISUSE of the part !

EXPECTING it to be a HIGHER HORSEPOWER item !

Yes, and it worked wonderfully. Both performance and gas mileage improved.

The intake (and recommended carb) were targeted for specific type of application and did well in those applications.

If you are starting with a factory high performace 4 bbl application and the goal is more power, you simply would not choose a SP2P as that is a complete misuse.

What was the vehicle and engine? What carb did you use with it.

A Mirida. 318 2 bbl.

I don't remember the carb specifics, but it was something like a 450 cfm 4 bbl. It was not a typical spreadbore, but the primaries were pretty small relative to the secondaries. It had real nice throttle response too.

Your carb was probably a Holley Economaster unit.They made a 450cfm,I had one on a 1976 Cordoba 400,it ran well actually with that carb,stock engine.

Boy intake manifolds made in the 50s seem to show engineering much far behind the 1970s. For example- Offenhauser- their manifolds are just a big plenum with a divider and thats it. Single plane design but not the legit single plane design as say a Torker TM7 and Street Dominator (All 1970s designs). Offenhauser and Weiands dual quad intake looks like they copied the mopar factory 413 dual quad intake. Nothing like the Edelbrock tried and true dual plane design. Im sure the compromises I mentioned are in that old single carb 383 intake you have. A used Performer (idle to 5500rpm) can be bought reasonably maybe cheaper than an OEM 1971 ish iron intake.. Id run that and be done.

years ago [around the 1982-83 ish time period if i remember right] i tried a split plenum single plane intake. i made the divider from 1/8" aluminum plate, and put a couple of locating notches in the carb flange to hold it into position. the "butt dyno" said i made an improvement, but i think the time slip said different.
i didn't spend much time trying to sort it out, so i can't say if it is something worth pursuing or not.
anyone else try this, and if so, what were your results ?