olddragger

iTrader: (3)

How many out their are not running screens in their revi intakes? If you did/have/do please share your results. I have been running without any screens for about 1 month--no issues(no benefits that I can tell). A very trusted source told me that the car will actually make less power without the screen.
comments--thoughts?
I am making a homemade replacement screen now to try out to see if I can tell a difference.
olddragger

rotarygod

The screens are only robbing about 1 hp apiece. That's it. Some cars have experienced idle issues without them which is why RB keeps a screen in place. If yours works fine without them, then keep it that way. The reason Mazda has 2 screens in place is for the same reason. They too were finding inconsistencies across the maf which affected the idle. The stock airbox bell mouth doesn't go all the way around as it would hit the filter if it did. this causes a slight flow variation through the inlet and across the maf which required Mazda to use 2 screens to straighten the airflow out to keep it smooth. RB has a perfect bell mouth shape all the way around so they get far more even flow distribution but for them they still needed 1 screen to eliminate the problems in all cars they tested. "some worked without the screens and others needed 1. If you don't have any screens in place and have no idle issues, leave it alone. You'll be fine. They aren't there for foltering ability and you aren't hurting anything without using them. Even if you had a slightly rough idle without them it still wouldn't be hurting anything. Don't worry about it.

r0tor

iTrader: (1)

the screens are dual purpose - to straighten airflow over the MAF, and backup protection to limit debris from entering the engine if the filter itself would fail.

Given proper placement of the MAF and proper design of the bell mouth, straightening airflow is not even a concern. As a filter, you can be your own judge to its merit and weigh the risks of not running it.

rotarygod

A filter would have to have catastrophic failure for those screens to be any additional filtering protection. The filter would literally have to blow apart in which case the screens would stop larger pieces of filter element from entering the engine. Lots of bad other things would get by in the process. I've never seen this happen. I've seen an undersized cone filter on a large high boost pressure turbo get physically sucked in which collapsed it but it still didn't fall apart or enter the engine. He's not ever going to have that happen. It's a well built filter and it's large. With the power level of the car where it is, airflow through the filter is quite slow. There is no stress on it. The screens themselves do nothing when it comes to filtering ability. They would only stop small pebbles. Tons of things that will kill an engine such as sand could easily pass right through them.

r0tor

iTrader: (1)

... never said it was likely, but i have seen first hand a foam type filter fail and chunks of foam get caught by the screens and I've seen pics of paper filters fall apart after getting wet.

again, the screens are there for a couple reason - if your willing to accept the risks involved with removing them there is no reason why you need them... but you should st least understand the risks you are accepting

dgrx8

i have a k&n typhoon2 short ram w/ no screen as per the k&n instructions. i have a tad bit of rough idling at times but my car has never stalled or given me any other issues.
i plan on adding the rb duct soon... been sitting in garage. i will post results here on the idling when i get it done.
good thread od...

olddragger

iTrader: (3)

I guess I am one of the lucky ones in where my car does ok without the screens.
THE ONLY WARNING I WOULD SAY IS THAT IF YOUR ARE INSTALLING THE REVI FOR THE 1ST TIME MAKE SURE THERE ARE NOT ANY LEFT OVER PACKING FOAM INSIDE THE INTAKE ITSELF!
You also will want to check the clamp/filter ever so often as I have a friend that the k&N filter came unclamped and was off and lying inside the airbox. Just maintainence thats all--heck ran recips for years with nothing inbetween the filter and engine.
Thanks for your response RG.and dgrx8
anyone else?
olddragger

Mazurfer

I installed the screen when I put on the Revi intake and Ram Air.
That's all I can tell ya. Have heard of people damaging the screen on install, so if you go put it on....be careful.

staticlag

interesting.

perhaps when I dyno I can test this.

Brettus

iTrader: (2)

using RB duct + stock intake + K&N drop in + 1 only screen here . No problems at all with idle .
However 1/2 an hr ago I decided to clean my K&N . After 10000 od km that thing was very dirty/gritty . Anybody with the RB duct should be checking their filters regularly .

anewconvert

When I owned a GTP I pulled the stock airbox off to put a fenderwell intake on instead. Pulled off the intake ducting, and what did I find? A small leaf plastered to the MAF screen. Would it have done any damage? Probably not. Probably would have burned real fast and been shot out of the engine without me ever knowing it. Did it make me happy that I had left the maf screen on when I switched back to my stock intake from the cold airbox I had? Yep.

That is not its purpose however. It is purely to straighten out flow. Go take the screen off your water faucet in your kitchen and turn the water on to see what the screen really does.

BC

Mazda-Rati

Were you running without a filter? A proper set up would have the filter BEFORE any kind of MAF screen to stop any small particals. How a leaf got passed the filter just doesn't make sense

Wilson

If a leaf got past your filter, then a screen is the least of your worries. You need to find the open gap (wherever it is) and close it up. I can't help but wonder how much trash made it inside your engine.

Mazurfer

Was wondering that myself!

Nemesis8

iTrader: (3)

What do people running velocity stacks do to protect the engine?

Brettus

iTrader: (2)

Prey

BlueRenesis82

screen doors. or they hope that they dont suck a rock in their vintage 427 mclaren can-am engine

linck32

i recommend you to use the screen, mine broke and because of that my car lost a lot of power; does anyone know where to get at least one of the screens?? or do i have to build my own??

sweatr

If you can't find it at the dealer, you might try a motor cycle dealer as the screens on a c- series motorcycle velocity stack are 2.5 inches in diameter and it is the same mesh.

Bluerenesis

I have always had one screen in for my REVi. May be around 8 years or longer without any stalling. A month or so ago I tore the screen while cleaning my K and N air filter so I left it out. Just yesterday while driving it a little longer than I usually drive it since I may average 15 miles tops per drive, the car stalled at a red light. I ran to lowes and bought brite aluminum screen mesh to try out for about 7 bucks. If it fails I am either going to by the honeycomb setup from another thread here that goes fro $35ish or try ordering online from a mesh specialist mentioned also in another thread. Before all of this I had an AEM intake with no screens and it stalled on long drives.

TeamRX8

iTrader: (25)

I haven't used one for years on my own custom CAI(s) and have never had an issue,

per Post #18 it has nothing to do with causing lower power as anyone who races can attest to ...