But i have an auto/non rev up, and from reading abunch on here, doing both the plenum spacer and mrev2, you dont get much of a gain by doing the mrev

 

You won't get much gain from the MREV with a non-revup, as it's a non-revup lower plenum......it's slightly modified (polished), but even Tony at Motordyne says it's not really worth the money....


Now that Cosworth plenum.......

 

mrev2 + 5/16 spacer --> revup (05+ 6mt)

1/2 or 5/16 spacer --> nonrevup (03/04 6mt, all 5at)

 

^+1

 

hmmm, interesting...

 

Didn't really see a review, but I don't need one since I can relate

The spacer definately makes a difference. I made the mistake of not purchasing the MREV2 (which I still have not) because it would have been a ton easier to install it; actually, it literally would have been no work at all since I still had to remove the lower plenum in order to install the iso gasket on the collectors.

As far as the MREV with a Non-Revup... it would work. But the problem is, you will run lean. Meaning, power is there to be made with a tune (correction of AFR)
I suggest you stick to the spacer and then get the MREV once your going to tune the car.

.

 

mrev2 is almost pointless for non revup motor. you will pay 400-450 and get 2-3whp . if you dont believe me or anyone else that tells you this go to MOTORDYNE's website and look at the dyno charts, if you dont believe that call Tony he will tell you. He is up front and honest, no BS with him, he is a good guy. I was talking with Tony about this same thing 2 weeks ago and even he said that for the $$$ it is almost worthless but it does give you gains and people want gains so he made the part available.

I woudl recommend buying the spacer and Test Pipes or HFC (high flow cats) you will get more power and the price is TP = little less HFC - a little more --- personally only buy Fast Intensions test pipes and cats... #1 without a doubt. Tony told me that with F.I. resinated test pipes and 5/16th spacer that I shoud get 21-24 whp...those are his numbers not mine guys.
good luck with what ever you choose

 

Hi Shyhorse,

Its not that the MREV2 doesn't give a good bang for the buck... By itself it works great. Its if you add it to a spacer on a non-revup engine that it has less bang for the buck.

By itself on a non revup engine, the MREV2 makes gains like the plenum spacer (~11-13HP) and a little more TQ.

If you add it to a non-revup engine that already has a spacer, it only makes another 4-6 HP through the midrange.

 

on my non-revup I've had 1/2" spacer since the IsoTherm came out... indeed there were gains (without a doubt)... when the revups came out and Tony started doing variations of the lower collector, I was intrigued... Obviously it's designed to replace the revup lower collector, but I've always wanted to know how well it would work on my configuration. Because it increases airflow, my first concern was running lean - of course everyone now mentions you will.

To get to my point... yesterday I installed an MREV2-esque and have an appointment with Shawn Church Thus for Osiris tune. I haven’t really seen much info about this configuration, so I'm gonna do it and see what happens... the only problem is I've also had a TBS (controversial I know) - so I won't know for certain how much of the improvement (if any) after the tune will be due to lower collector or TBS or both...

I've realized after 2 TS re-flashes that altering airflow and/or exhaust obviously changes A/F - but sometimes much more significantly than others... for instance, my ECU after it's first re-flash took well to the plenum spacer and gains were noticed immediately... after HFC I lost a ton of power until adjusting the A/F then I picked up a bunch of trq!

Right now, the car feels about what it did prior to the lower collector mod - so I know it's not pulling timing from running too lean - but I'm hoping it's lean enough that Shawn can add some fuel and see gains.

To further distort whether the collector improved anything, cam timing will be adjusted so it might be hard to tell if gains (presuming there will be some) after the tune is from better airflow or other aspects of the tune.

Like most performance enhancements on our cars - it's often the combination of mods that shows best results... but when you've picked the low hanging fruit and maxed out the obvious stuff - you look for little incremental stuff like this.

So I guess to summarize - unless you already have all the common breather mods and a good tune, just get the plenum spacer for a non-revup. Most cars I know of have responded well to it.

If anyone cares, I'll post impression after the tune on Thurs. Mind you this will be the 3rd ECU reflash so I don’t expect a bunch of gains - but adding the modified lower collector and TBS (I have my personal impressions about it) should help Shawn squeeze a little more power! If he gets a bunch, then kudos to him and Osiris!!! We'll see what happens.

 

This has been exceptionally informative!! I want to know if any of you out there are running a fujita intake, 5/16th or 1/2 spacer on an 04 sedan and have had a dyno. I also would be interested to know if anyone has any data about the leaning effect. If in fact there is a problem with A/F ratio should I change fuel delivery? I can't really understand why a spacer might cause this type of problem wheras other bolt-ons don't. My limited understanding of mechanics dictates that a change in the size of plenum of this magnitude should not cause a large enough change in oxygen that the ecu wouldn't be able to compensate. The amount of air that can be sucked in is limited by the throttle body diameter right? In the eventuality that it is lean I am having trouble finding a larger pump. Sorry for the barrage of questions but I have been up all night reading these posts and can't get straight answers.

 

A spacer on an 04 engine will run perfectly fine.

Its not untill you start adding a lot of mods that it starts to really make a difference on the A/F.

Intake, spacer, exhaust and test pipes is the "typical" limit you can go without a reflash.

Add headers and cams to that and you will definetly need a reflash.

 

Will the re-flash be enough to correct the a/f or will mods have to be done to

the fuel system? I would like to know the limits of the stock fuel system and

what the proper steps to take are when I run up against the wall.

ThX,
Will

 

You won't need any kind of fuel system upgrade unless you go FI.

 

What will be the best option for my car considering the upgrades and were I live?
I have 03 AT sedan with z-tube and Stillen CAI and I live in Denver, Colorado.

Thanks