1stgen8

iTrader: (1)

Ever since I bought an Umnitza intake several months ago I have been thinking about changing it over to a CAI with the least amount of cost. I posted a thread last month looking for one of the old Umnitza intake pipes for this project. One of the forum members helped me out....$20. I then ordered a s2000 CAI off ebay for $35 to complete my project. I did use a piece of screen just in front of the MAF sensor like the Umnitza setup that I removed from my ride. I will be starting the car within the next hour and hope I don't get a cel during the test run. I will keep you all posted. By the way I like my design better than the AEM CAI cause I have less breaks in the piping. I will like it a lot better if I dont get a cell. It only took my about 2 hrs to fab.

d j

what happened to the cf shroud?

TownDrunk

Pretty cool.

1stgen8

iTrader: (1)

I still have the complete Umnitza intake. You are looking at one of the old spare pieces of pipe that was sold with the first kits. If this intake works with no cels I may sell the Umnitza intake....it is the revised model.

1stgen8

iTrader: (1)

Well I did a test drive of about 8 miles....some on the highway. Car idles at 900 rpms with my custom intake....so that seems fine. Starting out in 1st gear the car sputtered when I got to 5k but once I passed 6k it smoothed out. I noticed it did this in all the gears up to 80 miles per hour. After driving around for about 10 minutes the car seemed to smooth out....only sputtering a little in first at take off. When I got home I checked all vac hoses for leaks.....can't hear any leaks. I think I may have to relearn the ECU. Don't want to jinx myself but no CEL at all. I know I will probably have to drive further than 8 miles before I can really tell but atleast I did not start out with one. My custom intake is half as loud as the Umnitza but it does have a nice sound at WOT.

Any suggestions.......I'm wondering if I should add another screen like the AEM intake.

MtlRX8

If you want to sell you Umnitza intake, pm me, I'm interested.

XDEEDUBBX

rotary extreme made an intake like this when the 8 first came out, it didn't do very well, hp was lost and caused many problems...

1stgen8

iTrader: (1)

I had to go back to the umnitza intake today. Yesterday my car seemed to be adjusting to the new intake. I double checked everything and decided to go for a ride earlier today. Well 5 mins into my ride things got a little worse. The car really started to break up between 5-6k in 1st, 2nd and 3rd gears. Then my CEL flashed about 6 times....only once in 3rd. Once I reduced my rpm's all seemed fine. The car also smelled really rich. Funny thing is it idled good and once I got over 6k it ran fine. When I put the umnitza back on I was scared as heck and thought I messed something up. The car was trying to stall out at idle and was missing really bad. It ran like it was flooded. I cleaned the MAF and reinstalled it. Then I drove around for 1/2 hour trying to avoid red lights.....now she runs like she did before. I'm wondering what the problem was and if I had added another screen to the intake would it work. I'm also wondering if it is the 2.75" pipe I used as apposed to the 3" umnitza pipe. I have to build up my courage again before giving it a second try. My wife was like, "You're always messing with stuff until you break it." I told her to go sit down somewhere. Hell, if you dont try you will never succeed.

Brettus

iTrader: (2)

hmmmmmm - the dia. at the maf was the same for both right ?
where did the pipe change dia. ? If it was right before the maf it could be some kind of turbulence occuring . I know its only 1/4" but on a volume basis it could be significant when you only have one screen in there.

I see now that it changes after the maf . That would suggest you need to change the maf mounting tube back to the stock dia - put a mesh sceen in just before the maf & make the dia transition on the tube before the maf tube.

I'm not an expert but hey - seems plausible .

1stgen8

iTrader: (1)

Yeah...all pipe was the same size. Only place it changed is where it flares out to fit into the OE rubber tube. I went with the s2000 CAI cause I knew it was the same size pipe as the old umnitza intake before it went to 3". One thing I was wondering is did I need to reconnect the green plug next to the MAF back into it's sensor. I did not connect it cause I think the AEM intake does not use it. However I did cap off the spout on the intake like the AEM install suggests. I may try it with two screens next week. Want to drive my car a bit longer the old way to make sure everything is ok.

XDEEDUBBX

i dont know what happened but this style has been tried and will not work..good job trying..

Brettus

iTrader: (2)

are you saying the umnitza is smaller than stock at the maf

1stgen8

iTrader: (1)

Not the new revised umnitza....like the one I removed to try this out. I bought one of the old pieces of pipe from the very first umnitza intakes.....that pipe was 2.75". They later revised it to 3" cause ppl were having a lot of problems with them but that still didn't work. Someone on the forum figured out it was missing the screen. Soooooo I thought there was nothing wrong with the old pipe just missing the screen. I placed the screen in the same place as the one on my working umnitza intake.....just before the MAF. Did not want to hack up my good working pipe for the project. Maybe the intake pipe size does make a difference.

Brettus

iTrader: (2)

By my calcs it would be 7% less area - which means the ecu thinks there is 7% more air flow - so I would say yes it does .
Compare the inside dia. of stock vs the tube you used .

TeamRX8

iTrader: (25)

I made it work

https://www.rx8club.com/showpost.php...3&postcount=41

Brettus

iTrader: (2)

[quote] Lid for the CAI air box cover, probably going to secure it with Dzus, still have some detail work to finish it all out, the MAF body runs dead-stone cold even after extended idling with the hood closed and no forward airflow : [quote]

you've just given me an idea Team - wonder if insulating the inside of the stock intake will give the same result you got ?

1stgen8

iTrader: (1)

The size of your pipe looks larger than the one (old umnitza pipe) that I used. Did you leave the green plug for the VFAD connected or just disconnect it. I had to remove the oem front intake tube (behind the bumper) in order to make mine cold air so I just left the green plug disconnected. I did cap off the vacuum spout on intake where the hose for the VFAD went.

If you used a larger pipe (like oem size) and left the green plug connected for the VFAD I can see how yours would work....it would be just like the revised Umnitza intake without the carbon fiber shell and pretty pipe.

TeamRX8

iTrader: (25)

it's the RP pipe I believe, got it from Marietta8, the ID matches the OE intake pipe and I added a single screen to it. I posted the screen info and source in this area somewhere. It's the key to preventing a CEL.

1stgen8

iTrader: (1)

I had a screen in mine just in front of the MAF.....like the umnitza one. I'm a really starting to think it had something to do with the pipe size.

TeamRX8

iTrader: (25)

I was referring to the previous comment about the RP pipe not working, they did not use a screen and they also only had an aluminum partition that let a lot of heat feed into the engine. I just made some improvements and these fixed all the issues.

XDEEDUBBX

i was refering to his intake pipe that goes all the way down to the front bumper.

Mazda-Rati

I thought the set up you are talking about was only for the 5spd/Euro-JDM version because the pipe ran down and placed the filter where the US/6spd has the passenger oil cooler.

1stgen8

iTrader: (1)

Hello all...I came up with a new design that works. Already put 20 -25 miles on the car with no CEL or hesitation at all. Car runs better than it did with the Umnitza. I really feel my first design was the pipe size and air filter. For my new design I had to hack up the stock airbox for the piping. Then I went to Advance and bought an APC Turbo Air Intake Filter .....very nice for APC if I may add. Filter cost $65 but it is worth it. Then I went to Lowe's and picked a three inch pipe coupler, one 4" coupler that tappers to 3"...in plumbing section and a few 4" inch clamps. I also used the two screens out of the stock airbox. Took a little work to the screen in between the pipe and couplers but they work like a charm. My project cost less than $100. I can give more info on how to do this if anyone else is interested. I still have a few finishing touches to add...like painting the stock pipe to dress it up.

If I don't have any problems with my custom CAI I will be selling the Umnitza.

Brettus

iTrader: (2)

Well done 1stgen - we need more people like you to pioneer these ideas .

What do you have outside the engine bay - or does it just collect air from the oval hole .

1stgen8

iTrader: (1)

I left all the stock piping behind the front bumper. I plan on designing something to make it ram air. Will keep you posted.