When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Also posted this on 460 ford, I have a set of d3 heads installed that I was told were ported considerably, however, I can't measure the valve diameter (it's on the engine) I have handwritten receipts that show no specifics, and a handwritten flow sheet maybe? I'm trying to figure out what all the numbers mean and if it seems to be a decent flowing head. I'm debating on reusing these heads on a new build. I can only assume the numbers on the left side are lift, other than that, those numbers mean nothing to me! Thanks everyone for your help!
If there is any math involved, I'm sure there is, if I take that top number on top " int 295" and multiply it by the decimal numbers, that replicates what they got for 254cfm at 500 lift.
295x.85=253.7~254
If this is the case what is 295 representing and what are the decimal numbers representing?
And finally, is 254 cfm at .500 any decent? And on the exhaust side 174cfm at .500?
If there is any math involved, I'm sure there is, if I take that top number on top " int 295" and multiply it by the decimal numbers, that replicates what they got for 254cfm at 500 lift.
295x.85=253.7~254
If this is the case what is 295 representing and what are the decimal numbers representing?
And finally, is 254 cfm at .500 any decent? And on the exhaust side 174cfm at .500?
Could the decimal numbers be before work (left side) and after work (right side)?
If so I would think they were just a 'clean up" for flowing but again I don't know what a good port job should flow?
I also hear if you are going to get them re-flowed you need a little more information from the first flow bench but cant remember what that is right now.
Dave ----
I'd like to think the 295 is intake port volume and 315 is exhaust, but is that even possible? These things are pretty restrictive, is it possible to hog it out that much? I like the idea of average flows, but average what? I wish I knew what size valves are in it now...
In the first post you suggest that that these heads have been 'considerably ported'
I don't think it would be impossible to increase volume by 11%, but I'm no pro.
Average the flow numbers of all eight intakes (or exhausts) to come up with a number for the engine as a whole.
Yeah, I had no clue at the time, and now I'm debating using them or porting my own. The guy could have been completely full of crap just trying to make a buck, I had no way to verify at the time. Because the numbers on the right increase with lift, maybe it is some calculation of flow, some how some way. It's just weird how they pulled the top numbers by intake and exhaust and calculated cfm at 500 lift.
Maybe I'm going about this all wrong, if those numbers were true, my 268 cfm intake at 600 lift is horrible. Mild port d3's show to flow 315 ish and 180 ish exhaust, I though factory d3's intake was closer to 300cfm? So that really can't be the right way of calculating cfm... Exhaust is nicer though. I'm thinking someone penned in hard numbers and somebody later wrote in pencil trying to make sense of it. I guess at this point all I can do is pull the heads and get them flow tested, or port the stock d3 heads myself. I was just seeing if any of those numbers or calculations jived with anyone's experience from porting those heads.
I would like to agree with you guys though that it would be nice to see the first number as a stock cc at x lift, and the number next to it was the ported cc at x lift, but that doesn't tell me much else.
what are your exact plans for this engine. If you want just a little more grunt for towing I wouldn't want heads that were ported big time. You can just knock the smog bump off the exhaust side a straight up timing gear set, long tube headers and good exhaust all the way back and a good dual plane intake and that will really wake up that engine for low end torque. I did just that to mine and boy howdy will that dude pull like a freight train. Now if your making a hotrod hogging them out is the way to go.
Just making a good tow motor, using factory intake and cast iron manifolds with straight up timing, never saw an improvement with the long tubes I have on it now, just a whole bunch of heat and retorqueing. the eddy intake was nothing more than a weight savings. Exactly like you said, I don't know exactly what these things are, so I don't know if I'd be better off using them or porting my own.
personally I would rather know what I have and port my own but as I said before if you just want more low end torque just knock the smog bump off the exhaust side and your there. If you port your heads and don't run those long tube headers you have wasted your time IMO. Get yourself some Percy aluminum header gaskets and never look back. You may have to retighten header bolts one time but then your done and they are even reusable. You say the Eddy intake made no difference, which one do you have and are you sure it is a dual plane cause I put mine on before porting and I could tell a difference.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
