Frankshaft wrote:- As far as port energy, you can call it whatever you want. That's fine. Its not a necessary "measurement" or one of the many port dynamics that exist. Someone that understand port "dynamics" knows that. Porting cylinder heads isn't about grinding, sticking it on the flow bench, flowing it, grinding more, sticking it back on there to see if it flows more. Its simply about sizing the port for the given application, creating complimenting areas within the runner, and then tuning the velocity profile to compliment the application. Its different for every application. maximizing what you refer to as port energy, will in most cases create a port that is to fast. One of the most misunderstood "dynamics" in cylinder head porting is velocity. Its not the most velocity you can create, but the correct velocity for the given application, that's the trick, knowing what you need. So, respectfully, I am not a follower of port energy. Sorry. I would blow most peoples minds on here, what I have made for power with every application under the sun. The kicker, at least half or more of the time, the heads NEVER went on a flow bench. One time, I hand ported a set of Indy 600-13x cnc castings from scratch, for a local dyno shop friend of mine, to replace a set of cracked and burnt up castings that BES did originally. My heads made 30 more hp on the same short block, vs BES's cnc'd set. The heads never went on a flow bench. I have a Saenz S-600 for the record, its my 3rd flow bench I have owned over the years. This usually bugs people, when I say this, but, a flow bench is an intermediate learning tool. I know its not, but I make that joke all the time. That quote was actually from Billy Glidden. I have picked up no less than 20 sets of AFR whatever. Fill in the blanks. BBC 357's, sbc 195,s,210's, 220's, 227's, 235's, etc etc, HUGE. Not even kidding. Usually to the tune of 40-60 hp. Why, because they have killer port energy. Reducing it makes WAY more power. Its not even about flow. Recently I re ported a set of RHS 200 heads I did for a 331 sbc road race engine. They were originally ported and had I would bet good port energy. Small port, fairly high flowing port. He built a new 377 short block, redynoed, and it quit a bit early. Re ported the heads for the new application, mainly to adjust the velocity profile, it gained minimal cfm, but made 35 more hp. The port energy as described was lower, but it made 35 more hp. I could go on and on with this stuff. Might not be able to articulate as well, with fancy graphs and the like, but I promise you, I know how to make real power, as well as anyone, and better than most.
I have thought long and hard as to how I should respond to your post here hence the delay.
I have followed pretty much all of your posts during the time I have been with ST. It is evident that you have well past a normal handle on things when it comes to making power so I am very reluctant to dismiss your comments lightly. As one of your recent post shows your porting dexterity is truly world class. My work looks just fine until placed next to what you are doing.
But that aside, I have come to the conclusion that the difference in our viewpoints is a failing on my part. Using port energy and specific energy is a is a little known but proven concept but the fact that someone of your caliber has failed to grasp it has most certainly demonstrated my failure to describe it and how it all relates to what we doing here.
You made a point about all the races your engines have won. This is good but I would like to remind you that my engines have won many many races including international ones. My best year delivered 5 national championships of which 2 were by winning every race in the series concerned. It’s not that I want to brag about this but rather point out that I must have had at least a half an idea what I was doing. My work with cylinder heads has even found it’s way into F1. How many ST posters can claim that let alone a guy like me who is so often rated among the semi clueless motor media.
I am certain I have something within the realms of cylinder head technology that I can teach you but more important for me is that I feel your extensive experience here leaves the door open for me to learn something of value from you.
In no particular order here, if you are agreeable, is what I would like to do:-
#1 Send you a complimentary copy of the flow bench program in question here.
#2 Have you evaluate the program and we converse privately back and forth on what and where you feel it, or I, is not delivering.
#3 Send me some heads that have demonstrated, in your opinion, really good dyno results and one that, again in your opinion, did not measure up to what you were looking for. With these I can assess the relevance of flow, velocity, discharge coefficient , port energy and energy density. These results will be between you and I unless you want to release them.
#4 Lastly have you got a SBF Windsor style head that performed very well on the dyno that can be made photo ready so I can show it in the SBF book I am currently working on?
PM me with your contact details if you are of a mind to push forward on this proposal.
David Vizard Small Group Performance Seminars - held about every 4 weeks. My shop or your shop. Contact seminar organizer at firstname.lastname@example.org for details.