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Old 07-22-2025 | 04:40 AM
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Originally Posted by madmax2
What do I know, I'll keep looking for information
OEM automobile man’s have to deal with hood height.

Anyway, looks like you can get ASM’s intake still.

https://azspeed.com/product/bb-chevy...tion-manifold/
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Old 07-22-2025 | 05:35 AM
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Originally Posted by Tartilla
pro-flo-xt-efi-intake-manifold-7136.html

The seem to only have a Rec Port version.
Ive extensively dyno tested the proflow intake, it makes outstanding hp. It is NOT a tq monster however with runner length at only about 5.5" or so, its very hard to get a boat thermostat under the throttle body but can be done with enough work and the right one. The throttle body itself by design needs a air flow entry device or it kills hp, on any single engine boat its virtually impossible to put that on tb and a cone filter that doesnt restrict flow/ kill hp . Putting a 90 degree elbow to feed a proflow intake or ANY intake NA is a waste of time, at that point youd be better having a conventional intake/TB.. As far as a oval port version, they made one once upon a time, Ive used 2 of them in builds, they will never make one again, its out of the question for unknown reasons, Smitty
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Old 07-22-2025 | 05:47 AM
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Originally Posted by madmax2
Modifying a dual plane is more difficult, the channels are in different planes and the injector will be in different planes as well.
I want the Holley Hi-ram, nice product.... I have it scheduled, maybe they will release an oval port version

The GM RamJet 502 it's nice, the port has fewer curves than the Mercury/ASM, no hay data about torque/power rpm band on 454.




No power added at the moment.
I'm looking forward to some aluminum heads (AFR, TFS, ProMaxx) but I was thinking about that later and making one improvement at a time.
Lingenfelter/Accel make a BBC two version of the Super Ram at the time...SuperRam Stealth, I'm going to investigate these too
The holley high ram 300-963 is a great looking intake, I been waiting to test one. In YOUR application it would be a HORRIBLE choice with CSA of 5.31" especially with thought that your going to be IRON vortec heads and the fact your engines small as BBC go at 454 ci. I cant stress this enough. You want to make supreme tq down low over what you had before/ have currently, that holley would make NO tq in that idle to 3000 your looking for as its sized for 500 + cubic inches and rpm band to 8000+. IF I had to pick a efi intake for a small cube bbc with idea of most tq from off idle to 3000, I would pick the ram jet 502 intake, its on small side but packaged nice.
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Old 07-22-2025 | 04:17 PM
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Originally Posted by SB
OEM automobile man’s have to deal with hood height.

Anyway, looks like you can get ASM’s intake still.

https://azspeed.com/product/bb-chevy...tion-manifold/
They advertise that it runs better than the GM Ramjet 502... but it is a rectangular port.
They've been selling an oval port on eBay for a while now.




Originally Posted by articfriends
Ive extensively dyno tested the proflow intake, it makes outstanding hp. It is NOT a tq monster however with runner length at only about 5.5" or so, its very hard to get a boat thermostat under the throttle body but can be done with enough work and the right one. The throttle body itself by design needs a air flow entry device or it kills hp, on any single engine boat its virtually impossible to put that on tb and a cone filter that doesnt restrict flow/ kill hp . Putting a 90 degree elbow to feed a proflow intake or ANY intake NA is a waste of time, at that point youd be better having a conventional intake/TB.. As far as a oval port version, they made one once upon a time, Ive used 2 of them in builds, they will never make one again, its out of the question for unknown reasons, Smitty
Oval port discontinued due to performance issues (I read it on an Edelbrock forum)

Originally Posted by articfriends
The holley high ram 300-963 is a great looking intake, I been waiting to test one. In YOUR application it would be a HORRIBLE choice with CSA of 5.31" especially with thought that your going to be IRON vortec heads and the fact your engines small as BBC go at 454 ci. I cant stress this enough. You want to make supreme tq down low over what you had before/ have currently, that holley would make NO tq in that idle to 3000 your looking for as its sized for 500 + cubic inches and rpm band to 8000+. IF I had to pick a efi intake for a small cube bbc with idea of most tq from off idle to 3000, I would pick the ram jet 502 intake, its on small side but packaged nice.
Holley say that power range of Hi-ram it's 1500-7000
I didn't find any comments about the RamJEt 502 and a 454, on the other hand it is the only oval port.

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Old 07-22-2025 | 08:22 PM
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Originally Posted by articfriends
The throttle body itself by design needs a air flow entry device or it kills hp,
Smitty, It appears that Spectre has stop making their Spectre 9604.
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Old 07-23-2025 | 06:43 AM
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Originally Posted by Rookie
Smitty, It appears that Spectre has stop making their Spectre 9604.
Theres (4) left in world to be purchased : https://ebay.us/m/lxKTMx , IDK why they discontinued that bell mouth
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Old 07-23-2025 | 06:53 AM
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Originally Posted by madmax2
They advertise that it runs better than the GM Ramjet 502... but it is a rectangular port.
They've been selling an oval port on eBay for a while now.





Oval port discontinued due to performance issues (I read it on an Edelbrock forum)


Holley say that power range of Hi-ram it's 1500-7000
I didn't find any comments about the RamJET 502 and a 454, on the other hand it is the only oval port.
The oval port edelbrock proflow was a rockstar when I tested it, made hp numbers on 502 like Id see on a 540. Again though , if ran with a 90 degree elbow on it , stock tb and no bell mouth, I wouldn't waste my time a performer rpm would kick its ass 10 ways from Sunday, this is true with any front mounted tb intake. The CSA on the new holley intake tells you everything, at over 5 inches,THATS BIG, your running VORTEC peanut port heads, wouldn't be setting world on fire with great tq numbers sub 4000, 4500. Now you could buy one, weld it up or splash zone the ports and make them appropriate size, contour the openings etc, unlike the proflow you'd be able to get to upper entry's without cutting up the intake

Last edited by articfriends; 07-23-2025 at 06:59 AM.
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Old 07-23-2025 | 04:21 PM
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I understand the point, my heads are not peanuts, they are oval 049, port matching with a gasket,
I was thinking of a long port design like the tunnel ram but with less height, the MR 500/525 intake seems to have longer ports than any other I've seen, it has a CSA that appears to be good (I don't know its measurements) and a large plenum.
From my limited knowledge, I don't see the downside to using it in a 454 NA; teachme please.
Another point that I find beneficial is how the injectors are located.






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Old 07-23-2025 | 04:45 PM
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Originally Posted by madmax2
I understand the point, my heads are not peanuts, they are oval 049, port matching with a gasket,
I was thinking of a long port design like the tunnel ram but with less height, the MR 500/525 intake seems to have longer ports than any other I've seen, it has a CSA that appears to be good (I don't know its measurements) and a large plenum.
From my limited knowledge, I don't see the downside to using it in a 454 NA; teachme please.
Another point that I find beneficial is how the injectors are located.



A long runner 500 intake (I think its 13.5" if I recall) will give you that long, flat tq curve your looking for. since it usually runs out to 5400 on a 502, Id expect you to get to 5700, 5800 before it becomes a restriction on a 454. a 454/502 mag intake is closer to 15.5" from memory. Ive extensively modded both, surprisingly the 500 intake did not respond great to mods and lost far more tq then I gained hp on top. Throttle body and what you bolt to it to keep dirt out is critical, in NA applications they hate anything that changes shape coming in. I dyno tested a "billet" adapter with KN filter on a modded 502 that took map from 92.5, 93 at wot to 88 or so and took hp from mid 500s to below 500, seen similar results with 90 degree elbows on feed side of throttle bodies so keep in mind practicality of how your gonna filter air coming in, Smitty
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Old 07-23-2025 | 05:21 PM
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Originally Posted by articfriends
Theres (4) left in world to be purchased : https://ebay.us/m/lxKTMx , IDK why they discontinued that bell mouth
Smitty,

You have one?

Thanks. Brad.
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