RAMM
Well-Known Member
I wondered this as well so I found some time to check 2 ports. An untouched port came in at exactly 153cc's. The port I had been working with came in at a whopping 154cc's. J.Rob
New Magnum heads for 347 with Flow data
- Thread starter RAMM
- Start date
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I wondered this as well so I found some time to check 2 ports. An untouched port came in at exactly 153cc's. The port I had been working with came in at a whopping 154cc's. J.Rob
Hebrews10:26
Banned
RAMM
Well-Known Member
Here is where some may find this very interesting. I know that some porting info you may run across tells you to concentrate on the bowl and valve job for maximum gains and to leave the pushrod pinch intake flange area alone. Well we already know that it is abysmally small at the pinch and when it's this narrow you can bet that the air is being accelerated to a very high speed here. The air will not be able to make the turn past the S.S. and head down past the valve at such high speeds. So I know from past experience that it is very important to gain some real-estate here on Magnum heads.
As you can see from the pic-I used the end of a 12mm wrench which measures .735" across as a guide and visual aid . The port was less than .690" here at the roof to start with. You can see that I really did not remove much at all.
So how did it impact the flow?
.1 63.3
.2 130
.3 185.3
.4 206.5
.45 199
.5 199
.6 199
The port still stalls but it is important to note that it sounded much better than previous tests above .400" J.Rob
As you can see from the pic-I used the end of a 12mm wrench which measures .735" across as a guide and visual aid . The port was less than .690" here at the roof to start with. You can see that I really did not remove much at all.
So how did it impact the flow?
.1 63.3
.2 130
.3 185.3
.4 206.5
.45 199
.5 199
.6 199
The port still stalls but it is important to note that it sounded much better than previous tests above .400" J.Rob
RAMM
Well-Known Member
There is a fairly large rib/vane that is cast into the floors of all the ports that runs right up to the S.S. that may be contributing to the ports early saturation. Next move is to take that out and retest. You can see it here, I've touched it with the burr to get it to show up better. J.Rob
AlV
Crabs in a barrel
Just the intake detail.
RAMM
Well-Known Member
Here is what happened once that rib/floor protrusion was removed. J.Rob
.1 63.6
.2 128.7
.3 185.3
.4 210
.45 207
.5 207
.6 206
.1 63.6
.2 128.7
.3 185.3
.4 210
.45 207
.5 207
.6 206
RAMM
Well-Known Member
At this point it's probably a good idea to give the port a little more area around the guide boss. Here is what it looked like after about 10 mins of fast carbide work. J.Rob
.1 64
.2 130
.3 189
.4 217
.45 214
.5 212
.6 212
Forgot to add: port volume is 160cc's now.
.1 64
.2 130
.3 189
.4 217
.45 214
.5 212
.6 212
Forgot to add: port volume is 160cc's now.
AlV
Crabs in a barrel
This update includes the removal of the rib/floor protrusion and increase in port size to 160cc.
RAMM
Well-Known Member
Thanks for taking the time to graph this. J.Rob
AlV
Crabs in a barrel
You're welcome!
Thank you for sharing your knowledge with us and making it available with such nice details. Your work is engaging me to get a better understanding of something I wouldn't ordinarily have access to.
I've been experimenting with line and plot graphs to find the best presentation for he data but at the moment the standard bar seems to be the easiest to interpret.
gtmopar
Phuckin A!
Great info guys
Great work Ramm! Much appreciated. Should make for a real responsive street engine,with low &mid range flow like that.
RAMM
Well-Known Member
I'm glad its being appreciated. I feel it's important to not get too caught up and start chasing a flow number. As it is now these flow numbers will support the power goals. However because the air speed is still way too high I may open the pinch further in an attempt to reduce turbulence. J.Rob
skrews
Well-Known Member
Solid gains for sure.
.1 65....64.....-1
.2 122...130...+8
.3 167...189...+22
.4 194...217...+23
.45 194..214...+20
.5 192 ...212...+20
.6 190 ...212...+22
Looks like a bit too much over hang on the SS in my humble opinion, but I know how the pics can be deceiving vs seeing in person. None the less in the big picture of what the build is targeted for they should rock. Lots of low RPM air speed should make for a very torquey responsive motor.
Thanks for the update. Much appreciated.
.1 65....64.....-1
.2 122...130...+8
.3 167...189...+22
.4 194...217...+23
.45 194..214...+20
.5 192 ...212...+20
.6 190 ...212...+22
Looks like a bit too much over hang on the SS in my humble opinion, but I know how the pics can be deceiving vs seeing in person. None the less in the big picture of what the build is targeted for they should rock. Lots of low RPM air speed should make for a very torquey responsive motor.
Thanks for the update. Much appreciated.
MopaR&D
Nerd Member
Just my $.02 from messing around with stock Magnums there were two main castings produced, one earlier that came on mostly 5.9's and some 5.2's and another later casting that became the replacement and started out mostly on 5.2's. The later casting has slightly smaller ports and combustion chambers; measuring the chambers myself the "early" casting had average volume around 66 cc while the later one was around 63 cc average.
This makes me really wish I had the means to port my Magnums before I put them on my 360 I feel like I could have made these mods myself pretty easily and picked up 20+ cfm... oh well I'll just wait till I upgrade to EQ's and port those ha
This makes me really wish I had the means to port my Magnums before I put them on my 360 I feel like I could have made these mods myself pretty easily and picked up 20+ cfm... oh well I'll just wait till I upgrade to EQ's and port those ha
RAMM
Well-Known Member
That is exactly the way I've geared this thread-So that anyone can do this. I have been trying very hard to NOT put them on the CNC and put an oval/venturi shaped bowl and knock the pinch out to an exact, straight size. The steps laid out here are so anyone with 2 different carbides can replicate.
The EQ's are an awesome head and with my valvejob flow an honest 239-241 cfm everytime. Beautiful casting they are. J.Rob
moper
Well-Known Member
I've always maintained the biggest issue with magnums is that pinch. So from what I can see (excluding the various retests) you've got about 20 minutes of grinding once you know where to touch. Correct?
RAMM
Well-Known Member
I would agree--20 mins per casting excluding valve job of course. J.Rob
luckysgarage
Well-Known Member
Great work. Really appreciate the time you're taking to share all of this information.
Graphs look nice too, AIV.
Graphs look nice too, AIV.
moper
Well-Known Member
With the EQ heads availability I'm mostly looking at this thread as an indicator of contrasting financials between reusing factory or buying those. I like the idea of tracking the improvements and reusing what one has I'm just not certain about the economics of it.
Hebrews10:26
Banned
This shows the amount of work just to end up with a closed chambered head that flows like a stock 1.88 360 head.
20 min per port, includes porting and NO valve job im sure. Not 20min per head
this is hillarious.
When you get done working a magnum head to where a mildly '250's cfm' ported La head flows, the port volume will the same..EXCEPT you will have major air speed issues from there out from things like the pinch and roof height . Get the ports big enough to slow things down, if you can without spending way too much time to almost get it and then having them crack on the motor.
what was it you said RAM, theres such thing as too much air speed? lol
And you started out pressing the velocity button and then turn around and tell me there "theres such a thing as too much air speed" back and forth you go.
You didnt respond to my points becaue they are all right on the money.
Ive been doing this for 18yrs, where you been??
Thanks again
20 min per port, includes porting and NO valve job im sure. Not 20min per head
this is hillarious.
When you get done working a magnum head to where a mildly '250's cfm' ported La head flows, the port volume will the same..EXCEPT you will have major air speed issues from there out from things like the pinch and roof height . Get the ports big enough to slow things down, if you can without spending way too much time to almost get it and then having them crack on the motor.
what was it you said RAM, theres such thing as too much air speed? lol
And you started out pressing the velocity button and then turn around and tell me there "theres such a thing as too much air speed" back and forth you go.
You didnt respond to my points becaue they are all right on the money.
Ive been doing this for 18yrs, where you been??
Thanks again
80fbody
Well-Known Member
What's hilarious? Anyone offering to spend the time to document actual flow changes to any mopar head is thumbs up in my book. Don't have a 318 but this data should be archived for anyone looking to build one, imo.
It was "Not including the valve job" just a few minutes with the grinder on the port.
Hebrews10:26
Banned
No the showing is great, it shows people facts...like these heads suck for anything other than a 318 or stock 360 emissions
its just watching someone learn that fire burns you...get the burn cream quick.
Anyone who really knows should be asking whats up with the dodging of my questions, does anyone really want to learn here??
Go ahead try and act cool and take 3 steps back, see you at the finish line.
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