http://www.youtube.com/watch?v=w9fviVILuPg<!-- m --> intro <!-- m -->http://www.youtube.com/watch?v=jKeIU3l2t90<!-- m --> walk-around <!-- m -->http://www.youtube.com/watch?v=2OzHBhB9S2A<!-- m --> fire up http://www.youtube.com/watch?v=DsoMCvBKP8E
Unsubstantiated challenge. Request for supporting evidence, unanswered. Education. You got to love the hamb
This is a good thread. Your work looks great, and I really enjoy the science behind this, and the fact that it supports what I've done too! This is the manifold currently on my Plymouth flathead. I built this one with the longest equal length runners that would fit. No design based on rpm bands per say, just figured it would work well with longer runners for lower rpms. They turned out to be around 25". Your formula says it should be best at 3600, and it does. It pulls hard. I don't ever want to turn this one above maybe 43-4400, and so this works well for me.
Don I need to ask a question, not that you should redesign your intake but to further the discussion of fluid theory. Your intake has the carbs mounted on top and the runner attached to the side causing the air flow to make a 90 degree turn, is there any advantage to the runners attaching to the bottom of the plenum and a slow turn to the valve. Does the plenum negate the the flow problem incurred by the change in direction. I see that in your application the winning factor is the design I hope you net gains in ET and HP and TQ. Thank you Ed
As long as he has strong vaccuum signal to pull the mixture in so it won't fall outta suspension, he should be good. Me, myself, I would've put a little more incline to it. Look to the FrenchTownFlyer! His car is truely wicked, I've followed since way back....
The plenumn absolutely negates the problem. That is what plenumns do. You can wiggle and dance all you want with long gentle sloping runners and turns but efficiency wise the plenum is hands down the most efficient method of making it work. I dont have the Fluid Dynamics text book right here but it is over 90 percent efficent while the best of what looks right is at best 70 percent. Us six cylinder guys forget that V8s other than tunnel rams always have a plenum and a turn. That is one thing I have learned if I have learned anything studying airflow and porting and working with my flowbench is that air does not behave how we think it does. It certainly doesnt behave what we think looks right either. In case many think I forgot this manifold. I did not. I just got sidetracked with the aluminum casting thing. I was back at it to day making wooden plugs to align the runners for tacking it together. This makes the alignment and holding together for tack welding much easier and less chance of error. It also helps me see how the runners meet the plate. 5 are real good but the one outside one still needs some work. (Tomorrow) After welding the wooden plugs can be pulled out from the outside. Don Others may do it another way. That is ok by me.
http://www.bgsoflex.com/intakeln.html http://www.wallaceracing.com/runnertorquecalc.php These are rough approximations.
Thanks Don and Screamin" for answering my question, the plenum serves more than the purpose of connecting the runners to the carb. I'm following this thread and your thread on melting pistons. I hope by saying melting pistons others will search to find out why. It has been very interesting reading to me, tho I may never melt a piston your journey is worth the read. Ed
Thanks. In the "big book" it says "teach us to number our days" (just came back from a funeral so it is fresh in my mind) which means DONT WASTE ANY! I am doing my best and i am having fun. The tunnel ram is awaiting my friends bottle of Argon but we have both been busy so I havent pushed it. The casting thing is going great. Now i would not even think of buying small aluminum parts when i can have them here in about 1/2 hour! Don
I was wondering the same thing Flipper, was doing some piddlin on the Belair today and wondered if he ever finished that intake!
I was just thinking he hasn't posted here in a while; I thought it was less than three years though!! I do hope he is well...[edit: profile says last post was a year and few months ago.]
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