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05-17-2018, 06:59 PM | #21 |
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Re: Long-Tube Intake Manifold
Quote:
Originally Posted by Talkwrench I bet it would run like a pig until everything was hot .. actually, when you look at that setup because there is no fuel running through the long tubes manifold temp wouldn't matter. it's got fuel injectors right at the base of the intake into the block. you won't have fuel falling out of suspension due to a cold, long intake runner. Yes, I was making a statement about the original post.. I can see the injection working , nice.
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05-17-2018, 09:12 PM | #22 |
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Re: Long-Tube Intake Manifold
What do you think is beneficial in using a long tube intake manifold on a flathead?
I see no advantage whatsoever |
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05-17-2018, 09:35 PM | #23 |
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Re: Long-Tube Intake Manifold
Pictures of mine are on my other computer at home. I'm running it at El Mirage this weekend, however. It is Ray's (Flat32) design. It has, however, no butterflies. It has a plenum with a throttle body for air control only and 8 injectors (one in each tube). I ran 151+ at El Mirage last November. I plan on doing better this weekend.
Wayno
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05-17-2018, 09:57 PM | #24 |
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Re: Long-Tube Intake Manifold
Elmo/wayne... I'll be a devil's advocate. You could gear, theoretically, a 12hp briggs motor to do 200mph if you had enough track. Please add more.
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05-17-2018, 10:24 PM | #25 |
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Re: Long-Tube Intake Manifold
Tinker, aerodynamic forces would gobble up them 12 horsies in short order.
Wayno
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05-17-2018, 10:30 PM | #26 |
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Re: Long-Tube Intake Manifold
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. Last edited by Tinker; 05-17-2018 at 10:35 PM. |
05-18-2018, 01:28 AM | #27 | ||
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Re: Long-Tube Intake Manifold
Quote:
Quote:
That's kind of the idea I was having here, to see if the airflow path could be straightened out and charge velocity increased to boost low-end performance. Tracing airflow through a stock manifold reveals the following. Outboard cylinders on one bank and the inboard of the other draw off the same carburetor throat, with cylinders 1 and 6 as well as 3 and 8 sharing a common runner. For practical purposes, the only way I envision this mess of tubing ever fitting under a vehicle hood is with two carburetors, each feeding four cylinders, maintaining the over-under design of a stock manifold. As some of you have suggested, side-draft carbs would probably be best. |
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05-18-2018, 07:02 AM | #28 |
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Re: Long-Tube Intake Manifold
Lift is a different physical property than drag. Remember, a glider can get lift under it's own power once it get's going.
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05-18-2018, 07:04 AM | #29 |
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Re: Long-Tube Intake Manifold
I wanted to ask Pete this same question. My thought is a ram effect, but I'm really curious on the intake was able to lower the RPM's. I'm not doubting, but really curious on this works. I find it fascinating.
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05-18-2018, 07:47 AM | #30 | |||
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Re: Long-Tube Intake Manifold
Quote:
just look at petes post. you are able to make more usable torque and more hp. it's not relegated to extreme racing engines. why do you think factory engines have long runners now?? they are all tuned intakes to give ram effects. Quote:
maybe in a vacuum. factor in any kind of drag and that's a bs statement. drag increases at the square of speed. if you want to go twice as fast it takes 4 times the hp to overcome the drag. it doesn't matter if it's a plane or a car, the coefficient of drag for any vehicle is a constant (for that particular vehicle) mostly they calculate drag out to the equivalent "flat plate area" for example a P51 mustang has approximately the same amount of force exerted on it by the air it's flying through as a flat board that is 2ftx2ft. Quote:
HP provides thrust in a plane, wings provide lift. if we compare your earlier briggs engine analogy to the airplane you are using now, that plane has infinite space to fly continually so per your logic should break the sound barrier!! |
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05-18-2018, 08:40 AM | #31 |
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Re: Long-Tube Intake Manifold
At a more convenient moment I'll try to get some pictures posted.
Wayno
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05-18-2018, 03:11 PM | #32 | |
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Re: Long-Tube Intake Manifold
Quote:
If you will notice closely sometime, race teams that use one car to compete on several types or lengths of tracks, will use different configurations of exhaust headers and intake manifolds. An excellent explanation of this was published in a book called "The Sports Car" by Colin Campbell in 1961. The basic principle of this is that the movement of the intake charge and the exhaust gas as interrupted by the valves causes pressure waves in the tubing it is traveling in. These pressure waves travel along the inner surface of the tubes building positive pressure ahead of them and negative pressure behind. If the tubing is cut to certain length, at a certain rpm the negative portion of the wave will occur precisely at the end of the tube and will cause a reflection of the wave. This reverse wave will travel back along the inner surface of the tube till it gets to the valve seat when it will meet the new wave and be reflected and reinforced causing a slight vacuum. This vacuum is what gives the incoming charge or the outgoing exhaust a boost in speed and increases engine efficiency. There are several other design parameters involved in using this system but this is the basic. |
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05-18-2018, 06:01 PM | #33 |
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Re: Long-Tube Intake Manifold
Or you can cheat and make your own pressure!
Btw, believe it or not the intake port length design still makes a difference with a blower or turbo. Pete, that Harmon Collins cam you ground for me will be at the heart of this setup eventually! |
05-19-2018, 11:02 PM | #34 | |
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Re: Long-Tube Intake Manifold
Quote:
But isn't it also limited to the pitch of the propeller also. Kind of like gearing or per say a osprey plane that can change the pitch of the propeller? Or why new cars have 5-6-8 sp transmissions with smaller engines. or why i installed a over drive unit in my flathead. Like maybe.... torque performance and gear ratios? when I'm at 4k rpms in 4th and switch to 5th which drops it 3k or below torque range? and I can't overpower the resistance. Just want to learn... Last edited by Tinker; 05-20-2018 at 01:54 PM. |
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05-19-2018, 11:16 PM | #35 |
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Re: Long-Tube Intake Manifold
torque being more relevant then hp.
seems to me with a briggs the weight of the transmission would be the biggest issue. maybe, But if it was geared right... I digress. . Last edited by Tinker; 05-19-2018 at 11:26 PM. |
05-20-2018, 03:00 PM | #36 |
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Re: Long-Tube Intake Manifold
I'm assuming you realize the HP is torque x rpm.
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05-20-2018, 06:36 PM | #37 | |
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Re: Long-Tube Intake Manifold
Quote:
Drag from air is your biggest enemy on top end speed. |
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05-20-2018, 07:10 PM | #38 |
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Re: Long-Tube Intake Manifold
true. Alright I'll back off. Although I still believe with the right conditions gearing/torque might be as important or more so, as hp.
Last edited by Tinker; 05-20-2018 at 08:13 PM. |
05-20-2018, 07:58 PM | #39 |
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Re: Long-Tube Intake Manifold
Yes I know you need hp to create torque. The idea was to apply gearing over torque range, not over peak hp. Granted aerodynamics and weight. okay... Found this video that talks torque and hp, it makes a strong case for the importance of torque in conjunction with hp. Certainly not exploring the earlier, but the traditional later. Faster/quicker. But does express gearing and torque mod'ed to hp or adding torque to hp. Not really going into gearing for torque only. https://www.youtube.com/watch?v=u-MH4sf5xkY torque over hp links. https://newatlas.com/top-ev-electric...op-fuel/50741/ https://www.youtube.com/watch?v=1Qaj2_0Ouos okay I'm done. Sorry, I apologize to the original poster. Last edited by Tinker; 05-20-2018 at 10:31 PM. |
05-20-2018, 08:59 PM | #40 |
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Re: Long-Tube Intake Manifold
Years ago a fellow ran a long tube manifold, Supposedly he said it made little difference if the tubes were on top of the carbs or mounted under the carbs.
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