Deleting the tumble flaps

[S0C0nFused]

Originally Posted by BowerR64

Now that i think about it, as the air rushes past that vent from the CAI its creating a draw from that vent and that draw has to come from some where so its drawing it right from the bottom. wow

It's called the 'Bernoulli principle' or 'venturi effect'. In our cars PCV system, the intake port is designed thus as air flows both ways (to and from) the intake depending on engine RPM. This 'draw' is not to be confused with engine 'vacuum' in the manifold. But is can be useful in a catch-can setup when you want a small amount of 'draw' from the PCV valve (as an example).

P.S. what paint did you use on the intakes? They look very good!!!

[BowerR64]

Originally Posted by S0C0nFused

Well, I am late to the party but I will input some info here as regards plugging the holes between the runners for any other folks wanting to do this. As the intake plastic is very hard and can be difficult to epoxy, the preferred method would be to use 'blind rivet nuts'. Specifically, a straight shank with a swag on the barrel. These fasteners are designed to embed into hard plastics. If that is not desirable (due to cost or difficulty pressing them in), then run a cone style steel wire brush through the holes, degrease, rinse and seal with 'PC-7' epoxy. I have had some experience sealing holes in plastics (unfortunately). The blind nuts are better as they have high mechanical grip. PC-7 is best as an epoxy as it will adhere to hard plastics (if prepped) and it is more of a paste/putty so you don't have runout like liquid steel.
Just FYI for future.

You know i haven't done allot plugging holes on plastic, these intakes are more of a composite then a plastic its got fibers in it and seems more brittle it acts allot like cast metal or something.

Anyway since i haven't done allot of work with this kind of stuff i wasnt going to risk sucking chunks of epoxy down into the valves. The way i did it was IMO the safest way to plug them and insure they dont get sucked into the intake.

Another thing i thought of doing was to bevel the back side of the "sleve" hole the flaps pivot in and then fill it. By beveling the hole on the back side as the epoxy, JBweld, quick steel what ever as it sets up that bevel will create a head kinda which i would hope would hold the rest of the plug from pulling threw into the valves. Again i didnt want to risk failure.

Anything metal was the last thing i wanted to use. Im sure sucking a rubber plug down into the intake valve will do just as much damage though.

There isnt much to work with on the sleve. Its about 1/4" thick and it fits tight into the intake runners. The backside is pretty flush.

[BowerR64]

Originally Posted by S0C0nFused

It's called the 'Bernoulli principle' or 'venturi effect'. In our cars PCV system, the intake port is designed thus as air flows both ways (to and from) the intake depending on engine RPM. This 'draw' is not to be confused with engine 'vacuum' in the manifold. But is can be useful in a catch-can setup when you want a small amount of 'draw' from the PCV valve (as an example).

P.S. what paint did you use on the intakes? They look very good!!!

Bernoulli? humm i think thats the first ive heard of that. I have heard of venturi though.

The paint? funny you mention that. When i did the PCV delete i painted it with brush on model paint. "steel" was the color. It took 2 full testors bottles and didnt look to bad but i didnt put enough clear on it and it chipped putting it back on.

I tried going over it with caliper paint. This is the issue i have.

When i did my calipers the first time man the duplicolor paint is awsome, its thick its really glossy and best of all when you put it on with a brush you dont see brush strokes as it sets up it smooths out and looks really good. I bought another can of black and did my rotors and the inside spokes of my winter wheels. That was the same way, really thick, glossy and went on really nice.

This time i think hey, now my intake could use a nice thick glossy coat of this caliper paint. WRONG the silver caliper paint sucks! its thin, runny and when it dries has no gloss. Maybe i got a bad batch i dont know but it sure wasnt like the black and red. Also the silver seems to seperate as you paint, you have to constantly stir it up or you get blotchy color changes as it goes on.

So yeah its dupli-color silver caliper paint. With several coats of clear high gloss wheel coating. Seems the wheel coating is very durable.

[BowerR64]

Originally Posted by Outlaw5.0

Correct, don't port match the intake port to the intake manifold opening, you could screw up the short turn radius.

One thing i wonder though in the picture, look how at the bottom of the intake ports looks like carbon build up.

Its like the intake was sitting to low on the head and the air is hitting that lip and backing up right there. If i ever did have any done i would think that edge could be rounded better. Just half moon the bottom edge a little taking that edge off. At the top its more clean which seems like its flowing better.

Maybe this is why they added the "tumble flaps" so the air rolls in at the top where the intake meets the head better?

[S0C0nFused]

Originally Posted by BowerR64

You know i haven't done allot plugging holes on plastic, these intakes are more of a composite then a plastic its got fibers in it and seems more brittle it acts allot like cast metal or something.

I hear ya! but what you want is mechanical grip. Rubber is not 'mechanical' like a sleeve or epoxy. Rubber has poor 'memory' and will let go. If the flanges are only 1/4" deep, then use a blind rivet or blind threaded insert (absolutely no chance of coming loose). But maybe that is to much hassle (not much room in there granted). Then may I suggest simple hard wood dowel. Rough up the plastic, then insert a dowel soaked in glue (note: at this time I don't which glue). A hard wood dowel will swell as the glue impregnates its fibers, making a very tight plug. Note: You want a glue that is fairly 'runny', and has a slow set-up time. But you will also want a glue that is not affected by gas when DRY, and has a good temp range! There are several that meet most of these criteria, fewer have the necessary temp range.

Paint >> I have found any 'metalic' paint is runny, and splotchy. I also don't know why. But they still look good!

[S0C0nFused]

Hey! I found something probably useful as regards plugging those holes.
www2.dupont.com/Plastics/en_US/assets/downloads/.../DCI283.pdf

I did not suggest simple self tapping screws as bad things can happen. But if you get the right type, then you have simple installation with high mechanical grip. Although I think the wood dowel bit would be better personally.

[Red Jay 918]

so this is basically the same as the charge motion delete plates on the Mustang?? or well similar anyways?

[Outlaw5.0]

yes.

[Jgrove998]

I do like the painting he did on the intake runners...really dresses up the stock manifold.

[BowerR64]

Played around with it today a little more. It seems ive lost a little low end acceleration. Idle to around 2-3k seems slower or more slugish but once it gets past that i feel a little more gain.

Not really what i wanted, i wanted more bottom end but im going to leave it because i think im going to install cams and a larger TB so maybe that will help?

I understand why they are there now, its a cool idea. When your at a lower RPM the flaps close down and force the air threw the smaller closed off opening i dont think it actually tumbles the air as much as it increases the velocity and i think thats where it helps.

I wouldnt recommend doing this. I think the stock intake is best left like it is so far.