psi_duster
Member
testing with EQ magnum heads.
Interesting video RPM Airgap intake flow.
- Thread starter psi_duster
- Start date
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ir3333
Well-Known Member
very confusing video...maybe i'm too thick? What is he saying?
Ya I seen that, but these intakes are known to work really well even on some big number hp builds, i figured they flowed around 250+ cfm.
What the video is showing is the cfm flow of the intake and how it flows less than the intake port there by limiting the intake port total flow abilities. AKA, it’s killing HP vs what the head is capable of in terms of total cfm flow through the head.
Since this is probably they best intake manifold out there in a dual plane style, imagine what a stock intake is killing.
ir3333
Well-Known Member
Tx..i wasn't sure which numbers were which. Now having said that, Hughes had an older video testing different intakes and surprisingly those intakes that flowed the most did not produce the highest HP. I think Dulcich has a
newer video were the airgap and RPM were compared on a big hp chev sm. block and there was no difference?
newer video were the airgap and RPM were compared on a big hp chev sm. block and there was no difference?
There is no flow difference from the RPM-AG and the standard RPM. The standard RPM is a heated intake. This means the intake gets hot and the air within it expands. This is less available air to mix with the fuel and rejetting should be needed.
When they’re cold, there is no performance difference.
The heated intake offers greater flexibility in all driving conditions, most notably, cold weather. As in actually cold, below 35*’s.
When they’re cold, there is no performance difference.
The heated intake offers greater flexibility in all driving conditions, most notably, cold weather. As in actually cold, below 35*’s.
good velocity though! 
And yeah.. having only one choice in dual plane sucks balls especially when the company and intakes are so badly made If i end up with hood clearance i will probably end up with a single plane, i went RPM cause i have no idea on height yet.
And yeah.. having only one choice in dual plane sucks balls especially when the company and intakes are so badly made If i end up with hood clearance i will probably end up with a single plane, i went RPM cause i have no idea on height yet.
The RPM will clear the hood on A bodies and the use of a drop plate air cleaner, like from Mancini Racing, will allow its use. I’m suggest you select an air cleaner but that is short and flat to clear the under hood insulation if you have it.good velocity though!
yup, i'm in a 62 b-body but there wasn't much clearance when the poly was in there, with the stock setup.. will get the LA going with the rpm then figure it out
If it doesn't' clear i will add one of these.
DionR
Well-Known Member
For what it's worth I run a Hughes RPM AG with a 1/2" spacer, Edelbrock AFB and a '72 trap door air cleaner with no clearance issues. No insulation though.
the 62 has a pretty low hood line.. it's just one thing to figure out when i get to it.. i already have the rpm ready so.. no biggy at this point..
33IMP
Well-Known Member
@Icetech, I don't believe you will have trouble with the rpm on a small block in your 62.
Mine has a dart raisin bran scoop, but it doesn't need it for carb clearance. My 440 has a team G single plane, 850 brawler, and a drop base a/c that came with the carb, and I have plenty of clearance, even without the scoop.
Heck, I've had a maxwedge crossramon it, with all the hood bracing intact, but I wasn't running aircleaners at that time. Air cleaners may have been a problem, at least the factory max repops might have been.
Mine has a dart raisin bran scoop, but it doesn't need it for carb clearance. My 440 has a team G single plane, 850 brawler, and a drop base a/c that came with the carb, and I have plenty of clearance, even without the scoop.
Heck, I've had a maxwedge crossramon it, with all the hood bracing intact, but I wasn't running aircleaners at that time. Air cleaners may have been a problem, at least the factory max repops might have been.
That's interesting, my poly had like 1" and was bone stock.... BUT.. my 62 has the 61 k-frame and powerflite mounts, might sit higher maybe?
33IMP
Well-Known Member
That is distinctly possible. Mine has the big block k member, and I have the mounts , but I built some elephant ears for it, while it was sitting on factory mounts. Pretty sure it is at stock height.
I can probably put a straight edge across the fenders and measure to top of the carb, if that would help.
Kinda also depends on what kind of air cleaner your poly had. My 9"tall 55chevy oil bath aircleaner would NOT fit on a 62, plymouth or chevy, lol.
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NICE! I have a trap door air cleaner myself. Had two, sold one to Rani. It’s on my 5.9, in a ‘79 Magnum now on top of a RPM & Edel. 750. Good to know this stuff.
Do me (Us the forum) a favor and find some clay to put on top & around the outside diameter of the high points of the air cleaner.
Measure them up.
I’m not fond of using the drop base air cleaner on my wife’s ‘67 Cúda. I can’t remember the exact amount of clearance the MP ribbed flat lid has over the carb, but the closer it sits the worse air flow is going into the carb. So I trolled through Summit for the diameter and height of the filter to use and found one.
DionR
Well-Known Member
Can do. Just need to find some clay.
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Rat Bastid
Dunamis Metron
Playdo (or however it’s spelled) and silly putty both work. So does most any modeling clay you can find about anywhere.
EQ Magnums of the better Aussie verity.
Check his channel for the work done in his videos.
Check his channel for the work done in his videos.
DionR
Well-Known Member
Wife had some playdo she uses with little kids when she teaches them piano so I figured I would just get this done.
RPM Air Gap with AFB and stock air cleaner to hood clearance measurements
In another thread I mentioned that I have an Edelbrock RPM Air Gap intake with a 1/2" carb spacer, AFB carb and a '72 trap door air cleaner and didn't have clearance issues with my hood. This prompted a request to take some measurements to see how much clearance there was. Instead of...
www.forabodiesonly.com
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What is the stock head flow of the Magnum head?
When you see an intake limit the flow of a head being tested, it’s not exactly safe but it does point to how limiting a factor it could be. So, re viewing the video, the head flowed 238 & 194 with the intake on.
This would suggest the intake only flows 190. This is not accurate since flowing the intake itself will show a lot more air flow. It’s the combination together. A flow great meets a flow great doesn’t always equal flow great. Perhaps Charlie can or will answer this question in the upcoming videos? IDK
If there is one thing I know for sure, a no doubt in my mind, is you want the best flowing intake to the cylinder head as possible. Should it be equal to the head? No, the intake should flow greater. As much as possible. More the merry.
This however doesn’t mean to put a well ported single plane intake on top if the cam isn’t going to match performance parameters.
No not really but it’s done every day of the week hundreds of times. Port the heads, screw the intake. I ran one dual plane intake in 47 years of playing with cars. And that was an LD4B on my 360 that I towed with. Guys are afraid of single plane intakes.
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