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Ram Pipes


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#1 blister

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Posted 10 November 2010 - 10:25 AM

just got a few questions

1. is it the longer the ram pipe the better for torque?
2. will a ram pipe and sock be better then just a standard air filter
3. also how much clearance do you need at the mouth of the ram pipe?

as you all know i am using a suck through supercharger set up so i have plenty of room at the front for a ram pipe and sock, so length isnt a problem to some degree

#2 MRA

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Posted 10 November 2010 - 10:29 AM

Ans..

1) generally yes, but also the shape has a lot to do with it as well.
2) a sock over a ram pipe will change the flow characteristics for the worse.
3) ??

#3 Cerberus

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Posted 10 November 2010 - 10:55 AM

Ans..

1) generally yes, but also the shape has a lot to do with it as well.
2) a sock over a ram pipe will change the flow characteristics for the worse.
3) ??



+1, when we took our crossflow engine to the rolling road, the bloke told us that the pipercross socks are useless.
And can potentially be dangerous, if you get spit back, they can become soaked in fuel then easily ignite.

A proper air filter, with plenty of room inside is much better than a sock.


With the ram pipe, if you can only fit a short'ish one, try and get one that has a large angle on the bell. This is what vizzard says in his book.

#4 blister

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Posted 10 November 2010 - 11:12 AM

what about those gauze things that go on he end of the ram pipe?

also 3. say if the the mouth being the end of the ram pipe how much area behind this do i need before it becomes very restrictive?

#5 MRA

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Posted 10 November 2010 - 11:21 AM

Look at it this way, if you have wire, nylon etc in the way it WILL cause a restriction of flow, it can even cause what should be laminar flow to become turbulent flow which is not good.

Try running around your garage.... ie a 90 degree sharp edged wall, see how close you can get to following the exact line of the wall, air is no different in this respect, so the smoother, larger the radius the better. The bigger the distance the better.

#6 mini93

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Posted 10 November 2010 - 11:23 AM

what you actualy do when you have long ram pipes is your changing the characteristics of the engine. When your valves open and close they cause the air to oscilate, if you tune your inlect tract you can get the oscilations to fill the cylinders more efficiently. The lengh in question is from the centre of the valve to the centre of the inlet/ ram pipe...but as we know on a 5 port everythings mixed around anyway.
Longer ram pipes will shift the torque slightly compaired to an identicle shaped but shorter ram pipe

#7 blister

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Posted 10 November 2010 - 11:23 AM

that is alright then!

well my plan now is to remove the spacer block between carb and vmax inlet to get an extra half inch, use the 3" long ram pipe with the k&n mesh filter at the end

#8 mini93

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Posted 10 November 2010 - 11:53 AM

with forced induction theres little point having a long inlet track, because your already getting high volumetric efficiencys, air being pushed into the cylinders rather than drawn in. Still worthwhile using a substack, a short block with the radiused edge to stop the blockage but only a short lengh

#9 Bungle

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Posted 10 November 2010 - 03:04 PM

someone needs to put Visards yellow book on their christmas list

#10 TopCatCustom

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Posted 10 November 2010 - 03:53 PM

If you are using a supercharger there is very little point worrying about the length of inlet tracts etc, the blower will beat the s**t out of the mixture, so NA tuning goes out the window in certain respects. A radius around the inlet will always be a good thing, and just use your head with the gap between the end of the trumpet and airbox, half the diameter of the ram pipe will be about enough, but shouldn't be crucial.

Remember with forced induction, the air is basically thicker so porting work will have a good effect, along with big valves, de-shrouding etc. The more space/length between the blower and engine means there will be more lag (I know it's not like a turbo but it still has to pressurise the chamber), if you can fit a charge cooler in there then it will be VERY good, FAR more beneficial than messing around with pipe lengths, my blower exit is about 6" from the inlet valves (V8 though).

I love superchargers- my current RV8 mx5 is making 370bhp at 7000rpm, and pulls like a train from about 2000rpm, it makes me VERY happy :) Turbos are cool and much more potential on road cars but blowers are so old skool!!! Is this engine runnin yet and just changing carbs or is it a build in progress?

#11 blister

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Posted 10 November 2010 - 06:04 PM

it is running but the belt likes to jump of and it isnt tuned yet,



i do have a vizard book but i cannot find it for the life of me




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