BBC intake flow
07-20-2025 | 06:13 PM
#11
Registered
Joined: Aug 2019
Posts: 1,233
Likes: 417
From: BC
RamJet 502
Ramjet 350
That's right...the Ramjet GM crate engines. The 350 version is more like a TPIS Mini ram. Solution from the GM TPI system.
The BBC 502 Ramjet intake looks interesting, but it appears to have some sharp turns into the head ports.
The Holley FI tunnel ram style FI intake has a better intake port entry angle.
The benefit of FI BBC intakes like these...is the underhood clearance.
Ramjet 350
That's right...the Ramjet GM crate engines. The 350 version is more like a TPIS Mini ram. Solution from the GM TPI system.
The BBC 502 Ramjet intake looks interesting, but it appears to have some sharp turns into the head ports.
The Holley FI tunnel ram style FI intake has a better intake port entry angle.
The benefit of FI BBC intakes like these...is the underhood clearance.
07-20-2025 | 09:05 PM
#12
Thread Starter
Registered
Joined: Jul 2025
Posts: 28
Likes: 10
From: Buenos Aires, Argentina
performer rpm with injectors would be interesting. I know many have done it, various different engines, and they had a hard time tuning them. Not sure who they where and what systems they used… I’m sure you could would get it done. 
:wink :lol
Sorry for slight side track, smitty, you need to find a customer wanting one of these. They (Holley) finally makes one for the bbc ! Would love to see how it works out.
https://www.holley.com/products/engi.../parts/300-963
:wink :lolSorry for slight side track, smitty, you need to find a customer wanting one of these. They (Holley) finally makes one for the bbc ! Would love to see how it works out.
https://www.holley.com/products/engi.../parts/300-963
I want the Holley Hi-ram, nice product.... I have it scheduled, maybe they will release an oval port version
I think the same
so they used a intake called a "ram jet" on some crate 502s, a local guy on ebay has had a new intake only for sale on ebay forever under rosebush motorsports, lingenfelter used the 502 mag intake modded on a bbc in a suburban once upon a time. Do you have one laying around your thinking of using? the 502 mag intake is ugly and heavy, would pull un modded to 5500 or so on your cubic icnhes I built, dynoed and tuned 2 454 mags w whipple sidemounts. I modded the 454/502 mag intakes heavily and running NA with bored out throttle bodies before bolting the superchargers on made 550 or so hp , peaked t 5600 , fl;at lined to 5900 . Keep in mind though the intake mods (cutting runners shorter) gives up tq from idle to 3000 or so. Interesting project. I recently built and dynoed a moderate 496 for a 70 chevelle using promax 290 heads, 10.5-1 compression, performer rpm intake and 830 annular discharge carb that made 635/635 and came off idle making torque like a turned up diesel, would be interesting to see someone add injector ports on a performer rpm, Smitty
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
07-20-2025 | 09:48 PM
#13
Thread Starter
Registered
Joined: Jul 2025
Posts: 28
Likes: 10
From: Buenos Aires, Argentina
I started looking at the modern OEM intake designs for the Chevrolet LS, Ford Coyote, and Mopar Gen 3 Hemi.
They all have long ports curved at over 180°, all of them.
The closest thing to those designs is the ASM/Mercury 500/525.
I refuse to believe that what works for Mercury/Chevy/Ford/Mopar won't work for me, BBC 454.....
The intake design Ligenfelter developed for the C4 Corvette is conceptually very similar to the ASM/Mercury design as well...
LS3 intake
Coyote Mustang 2018
Mopar SRT 6.4L
They all have long ports curved at over 180°, all of them.
The closest thing to those designs is the ASM/Mercury 500/525.
I refuse to believe that what works for Mercury/Chevy/Ford/Mopar won't work for me, BBC 454.....
The intake design Ligenfelter developed for the C4 Corvette is conceptually very similar to the ASM/Mercury design as well...
LS3 intake
Coyote Mustang 2018
Mopar SRT 6.4L
07-21-2025 | 01:40 AM
#15
Registered
Joined: Aug 2019
Posts: 1,233
Likes: 417
From: BC
Airflow is not intuitive.
Check out some of the Live (recorded) Darin Morgan vids on YT Dragboss channel.
Darin is one of the best intake manifold guys, and one of the only one's sharing his info.
He speaks very plain language on anything over a 7° radius corner angle will be turbulent.
Just an FYI...a 100ft cube of air weighs 40Tons.
FI intakes are mostly a dry flow (no fuel atomized & suspended)
The LS intakes are flat only because they have hood clearance restrictions. The best FI intakes would look more the Ferrari cross ram FI intakes.opposing plenums with straight runners right into the head int ports. With a butterfly valve elec controlled to open pressure pulses between plenums as tuning.
Have a look at Pipemax software.
Worth every penny of the $150. It would go through what you would need to for your engine for intake and exhaust, and give all the harmonic tuning lengths etc.
As Arcticfriends mentioned, the Mercury Racing chokes off at 5500 area. But it's likely restricting airflow from optimum potential before it really chokes off.
Check out some of the Live (recorded) Darin Morgan vids on YT Dragboss channel.
Darin is one of the best intake manifold guys, and one of the only one's sharing his info.
He speaks very plain language on anything over a 7° radius corner angle will be turbulent.
Just an FYI...a 100ft cube of air weighs 40Tons.
FI intakes are mostly a dry flow (no fuel atomized & suspended)
The LS intakes are flat only because they have hood clearance restrictions. The best FI intakes would look more the Ferrari cross ram FI intakes.opposing plenums with straight runners right into the head int ports. With a butterfly valve elec controlled to open pressure pulses between plenums as tuning.
Have a look at Pipemax software.
Worth every penny of the $150. It would go through what you would need to for your engine for intake and exhaust, and give all the harmonic tuning lengths etc.
As Arcticfriends mentioned, the Mercury Racing chokes off at 5500 area. But it's likely restricting airflow from optimum potential before it really chokes off.
Last edited by Tartilla; 07-21-2025 at 01:44 AM.
07-21-2025 | 12:04 PM
#16
Registered
Joined: Jan 2003
Posts: 6,020
Likes: 1,522
From: Grand Rapids, MI
I've been waiting for Holley to release this. But I just saw a back to back dyno overlay between the Holley HI-Ram and the Edelbrock Pro-Flo XT 7136 and they were pretty much identical. I guess I'll just stick with my Pro-Flo.
,
They (Holley) finally makes one for the bbc ! Would love to see how it works out.
https://www.holley.com/products/engi.../parts/300-963
https://www.holley.com/products/engi.../parts/300-963
,
07-21-2025 | 10:41 PM
#17
Thread Starter
Registered
Joined: Jul 2025
Posts: 28
Likes: 10
From: Buenos Aires, Argentina
Airflow is not intuitive.
Check out some of the Live (recorded) Darin Morgan vids on YT Dragboss channel.
Darin is one of the best intake manifold guys, and one of the only one's sharing his info.
He speaks very plain language on anything over a 7° radius corner angle will be turbulent.
Just an FYI...a 100ft cube of air weighs 40Tons.
FI intakes are mostly a dry flow (no fuel atomized & suspended)
The LS intakes are flat only because they have hood clearance restrictions. The best FI intakes would look more the Ferrari cross ram FI intakes.opposing plenums with straight runners right into the head int ports. With a butterfly valve elec controlled to open pressure pulses between plenums as tuning.
Have a look at Pipemax software.
Worth every penny of the $150. It would go through what you would need to for your engine for intake and exhaust, and give all the harmonic tuning lengths etc.
As Arcticfriends mentioned, the Mercury Racing chokes off at 5500 area. But it's likely restricting airflow from optimum potential before it really chokes off.
Check out some of the Live (recorded) Darin Morgan vids on YT Dragboss channel.
Darin is one of the best intake manifold guys, and one of the only one's sharing his info.
He speaks very plain language on anything over a 7° radius corner angle will be turbulent.
Just an FYI...a 100ft cube of air weighs 40Tons.
FI intakes are mostly a dry flow (no fuel atomized & suspended)
The LS intakes are flat only because they have hood clearance restrictions. The best FI intakes would look more the Ferrari cross ram FI intakes.opposing plenums with straight runners right into the head int ports. With a butterfly valve elec controlled to open pressure pulses between plenums as tuning.
Have a look at Pipemax software.
Worth every penny of the $150. It would go through what you would need to for your engine for intake and exhaust, and give all the harmonic tuning lengths etc.
As Arcticfriends mentioned, the Mercury Racing chokes off at 5500 area. But it's likely restricting airflow from optimum potential before it really chokes off.
07-21-2025 | 10:42 PM
#18
Thread Starter
Registered
Joined: Jul 2025
Posts: 28
Likes: 10
From: Buenos Aires, Argentina
07-22-2025 | 12:45 AM
#19
Registered
Joined: Aug 2019
Posts: 1,233
Likes: 417
From: BC
07-22-2025 | 03:37 AM
#20
Registered
Joined: Nov 2004
Posts: 14,108
Likes: 3,694
From: On A Dirt Floor
Rookie Good info. Can you share a link so i can see the particulars of the engine build.
I shared pipemax results years ago here on OSO for marine pump gas 500cid engines . Was one of arcticfriends threads when doing intake mods on 502mpi and etc.
If you dig thru google search you may find it. OSO’s search suks.
Airflow is not intuitive.
Check out some of the Live (recorded) Darin Morgan vids on YT Dragboss channel.
Darin is one of the best intake manifold guys, and one of the only one's sharing his info.
He speaks very plain language on anything over a 7° radius corner angle will be turbulent.
Just an FYI...a 100ft cube of air weighs 40Tons.
FI intakes are mostly a dry flow (no fuel atomized & suspended)
The LS intakes are flat only because they have hood clearance restrictions. The best FI intakes would look more the Ferrari cross ram FI intakes.opposing plenums with straight runners right into the head int ports. With a butterfly valve elec controlled to open pressure pulses between plenums as tuning.
Have a look at Pipemax software.
Worth every penny of the $150. It would go through what you would need to for your engine for intake and exhaust, and give all the harmonic tuning lengths etc.
As Arcticfriends mentioned, the Mercury Racing chokes off at 5500 area. But it's likely restricting airflow from optimum potential before it really chokes off.
Check out some of the Live (recorded) Darin Morgan vids on YT Dragboss channel.
Darin is one of the best intake manifold guys, and one of the only one's sharing his info.
He speaks very plain language on anything over a 7° radius corner angle will be turbulent.
Just an FYI...a 100ft cube of air weighs 40Tons.
FI intakes are mostly a dry flow (no fuel atomized & suspended)
The LS intakes are flat only because they have hood clearance restrictions. The best FI intakes would look more the Ferrari cross ram FI intakes.opposing plenums with straight runners right into the head int ports. With a butterfly valve elec controlled to open pressure pulses between plenums as tuning.
Have a look at Pipemax software.
Worth every penny of the $150. It would go through what you would need to for your engine for intake and exhaust, and give all the harmonic tuning lengths etc.
As Arcticfriends mentioned, the Mercury Racing chokes off at 5500 area. But it's likely restricting airflow from optimum potential before it really chokes off.
If you dig thru google search you may find it. OSO’s search suks.
