Onservation about magnum 5.9
The fuel injected 5.9 is managed by a computer with mostly a fixed tune. Has anyone here flowed/determined what the kegger flows? I hear as cast it is around 190's cfm per runner. Now that kegger manifolds runners taper down somewhat drastically at the flange/intake face FWIW. If you gasket match that and open that tapered section ...it will flow a lot more. Side note was it on purpose to speed the air at the injector? I've opened it up and have not felt any negative from it in fact it hauls *** and if I did lose an inkling of torque it was probably about 300 RPMs worth sooner, maybe. Now still staying on the mag vs mag , kegger vs dual plane/4 brl.... the kegger is designed for idle to maybe 5000 rpm, probably 4800 rpm ...but the stock valve springs wont allow more than 4200 rpm or so 'worn and tired @85 seat/ 190lbs open, stock new is 90/200'..
So a factory Magnum kegger designed for 5000 RPM and under, with tiny runner windows... springs designed for Max RPM of around 4500 rpm...
The cam is not the issue as much as the above, believe it or not.
Makes sense that a version with more air/fuel dual plane/4brl, no stock computer tune and some better springs or cam will rev faster alright.
For what it's worth I put some really good heads on my 5.9 Magnum in my truck that has to pass California smog 'has the stock hyd roller cam" I also upgraded the valve springs and Port matched the kegger and put some Summit headers on it + ultra flo muff.
It revs no problem to 4800 and does it quick...though ultimately the computer caps the output.
Imo the intake design and valve springs are 1st, computer second, exhaust 3rd...and cam last as to why it does or doesnt "rev fast".
There's a couple reasons to this...But being that you also compared the engine with a carburetor to itself with injection... let's go there.
The fuel injected 5.9 is managed by a computer with mostly a fixed tune. Has anyone here flowed/determined what the kegger flows? I hear as cast it is around 190's cfm per runner. Now that kegger manifolds runners taper down somewhat drastically at the flange/intake face FWIW. If you gasket match that and open that tapered section ...it will flow a lot more. Side note was it on purpose to speed the air at the injector? I've opened it up and have not felt any negative from it in fact it hauls *** and if I did lose an inkling of torque it was probably about 300 RPMs worth sooner, maybe. Now still staying on the mag vs mag , kegger vs dual plane/4 brl.... the kegger is designed for idle to maybe 5000 rpm, probably 4800 rpm ...but the stock valve springs wont allow more than 4200 rpm or so 'worn and tired @85 seat/ 190lbs open, stock new is 90/200'..
So a factory Magnum kegger designed for 5000 RPM and under, with tiny runner windows... springs designed for Max RPM of around 4500 rpm...
The cam is not the issue as much as the above, believe it or not.
Makes sense that a version with more air/fuel dual plane/4brl, no stock computer tune and some better springs or cam will rev faster alright.
For what it's worth I put some really good heads on my 5.9 Magnum in my truck that has to pass California smog 'has the stock hyd roller cam" I also upgraded the valve springs and Port matched the kegger and put some Summit headers on it + ultra flo muff.
It revs no problem to 4800 and does it quick...though ultimately the computer caps the output.
Imo the intake design and valve springs are 1st, computer second, exhaust 3rd...and cam last as to why it does or doesnt "rev fast".