just sent my magnum eddy heads and single plain magnum intake to Jeff at modern to get fully ported, Was wondering if you guys had any ideas how much horse power im gonna gain just looking for a ball park idea i know its hard to know for sure
Thanks

depends on your combo. if the porting is optimized for your cam (and vice versa), you could see pretty significant gains. jeff would probably have a pretty good idea what you could gain.

If your combo can support it, the flow gain could be worth up to 2 hp per cfm gained. So if the head flow goes up 30 cfm, it will support 60 more hp... if the rest of the combo will support it. Rough, but without any other info, that is all I can offer.

The cam is about .588 lift intake and .595 or so on exhaust not sure of the duration dont have the cam card in front of me, but thanks a bunch for the info

We run mostly 1/8th down here in NC, Just had Shady Dell do a Stage 2 (from maybe 240-ish to 270+) on my Eddies for my 12:1 414, hoping that ~30cfm nets me another 50 or so HP, which for me also allows me a higher RPM cieling to where I won't have to take gear out of my comb when I run the 1/4.

As said it really depends on the rest of the combo, and if the short block you have has hit it's "saturation point" VE wise with the Compression, cam and induction you have. In other words is it to the point where Head flow is the main thing holding it back (causing/resulting in the power falling off)

i spent crazy money having ray barton do my eddies,they said 311cfm which was way off the local shops flow bench..2600 for a tenth..mistake that wont be made again,car did 10.90's after it did 10.80's

2,600 for 10 hp