Sixline

I recently upgraded from Rogue Tuning's A-Tune to his M-Tune I thought I would post a review.

First off, it took a little over a month to get mine. The company that Joshua gets his custom air filters from decided to take forever so it wasn't exactly his fault. It did give me a reason to annoy him though. He also decided to start working 18 hour days which makes getting a hold of him a little difficult. Future buyers, be patient as he does Rogue Tuning as a side business.

Joshua stop working 18 hour days, the 944 community doesn't want you to die on us.

The install went fairly smooth. Installing the DME chip is fairly basic, nothing complicated. Installing the injectors, again, fairly simple. I also installed a new 3 bar FPR and new damper while the fuel rail was off. The MAP sensor was already installed since I had the A-Tune.

Now, fitting the MAF pipe and air filter was a different story. I was expecting it to fit a lot better than it did. It would of been nice to have some pointers on this but not a huge problem. I knew the alternator shroud was going to require some trimming and in the end I should of trimmed it a lot more but left it since I will be doing the Nissan Quest alternator mod soon. I also had to trim about an inch off each end of the 45 degree silicone hose in order to get the air filter to fit. It seems that the air filter rubs on everything and I am hoping this doesn't cause holes in the filter.

The MAF pipe eliminates the fitting that goes to the cycling valve so any future buyers be prepared to install some sort of boost controller. I was going to leave mine in place temporally as I don't have a boost controller yet and I had to ditch that plan. So right now a Lindsey Racing boost enhancer is working as a crappy manual boost controller. My fault.... I have a Tial wastegate and manual boost controller on the way.

The car started right up after I was done installing everything.

First off, when the car is idling it hesitates a little bit when you give it gas. It almost stalled on me once. Not really sure what would cause this as it doesn't happen all the time. The car will also buck when coming to a stop if you let the RPMs get near 1400, injectors coming back on? With the A-Tune I would let the RPMs get near 1100 before pushing in the clutch and never had an issue. Last thing I noticed is that the car will occasionally sit at around 2000 RPM for a few seconds before dropping to idle, like your holding the throttle. Again it doesn't happen all the time and I never noticed it happening when the car is warm. No problems cruising or boosting.

I also picked up the logger as well which is really cool. Very easy to install. One thing I noticed is that the boost pressure that it is reporting doesn't match what my boost gauge is telling me. At 15 PSI on my mechanical boost gauge the logger is reporting 11 PSI. Which is right?

So partial review at this point since I am having some problems, sorry Joshua. I will update this thread as things progress. Overall I am impressed and can't wait to get everything running smoothly. Last thing, anybody looking for that Fast and the Furious blow off sound get the M-Tune, it is loud. I will get some pictures up and possibly video soon.

Sixline

Rogue_Ant

Glad you got the kit and installed. Yes, I am a bit behind on orders at the moment...

The kit will fit without modifying anything. It is a tight fit, and it might be easier to fit by cutting the 45° a bit and/or getting the Quest alternator. But the kit was setup around an otherwise stock Turbo-S.

The reality is that there isn't much room to work with.

Regarding your running issues. The hesitation is most likely fuel related. Are you on Gas or E85? What FQS position?

The buck is the injectors coming back on. But going from the AFM to the MAF, generally you need to reset the idle. Follow this procedure:

http://www.clarks-garage.com/shop-manual/fuel-08.htm

Going to MAF, removes the restriction of the AFM. Typically causing the idle to be high, and the RPM hang you mentioned. This should be fixed by doing the clarks-garage idle reset.

The boost value discrepancy is due to our altitude. The MAP sensor (logger) is the correct one. The MAP sensor is measure absolute pressure, while your gauge measures pressure over atmosphere.

And yeah, the diverter-valve sound is much more pronounced. Just a side-effect of removing the AFM restriction.

User 52121

I did both (trim the elbow AND install the Nissan alternator). Otherwise it's all a VERY tight fit, no doubt.

I noticed the "burp" too when the injectors come back on. I think it's exaggerated more if you have a lightweight flywheel. I have a LWFW in my car and mostly got rid of the burp with the tuner. And the idle "hang" (if you've ever driven a manual trans Ford Mustang... they all behave exactly like this!) I resolved mostly by resetting the idle as Rogue suggested. I made further tweaks with the tuner. From what I remember based on reading the descriptions in the various tables, etc. is that idle will "hold" slightly higher based on how high the RPMs were (and for how long) prior to closing the throttle. It's to keep the motor from stalling if you suddenly drop the throttle from high revs. All of this is adjustable in the tuner.

Sixline

Yeah no complaint, you kept me updated.

Again no real complaint, wasn't expecting it to be so tight but in the end it did fit.

FQS is at 0 and I am running 91 Octane, AFRs are pretty spot on. The plan is to run E85 after I upgrade the fuel pump. If you think the stock pump will keep up with the K26/6 I can switch now but everything I read said not to even attempt.

Yeah I will do that this weekend.

It seems that this only occurs right after a cold start up but I will have to test it more. I will try to capture it on the logger.

Hmmm, I understand the different ways they get their readings but now I am not sure what to trust. The last thing I want is to blow my engine up. I will do some more logging at certain boost pressures and see if they match up on the logger.

Here is a log file. I don't have my wideband hooked up yet but will do it this weekend. I still need to get the proper definition file from you for my PLX wideband.

Sixline's Test Run.zip

Here are the formulas for gas and E85.

alxdgr8

Have you pressure tested everything to make sure you don't have vac/boost leaks?

Rogue_Ant

Sixline, the logger/MAP sensor is the one to trust.

Your gauge is only showing you pressure above atmosphere pressure. However, we start off at less atmosphere pressure than someone at sea-level. Denver altitude typically results in around 3psi less atmosphere pressure. So, a boost gauge will say 15psi, but that is only the same as 12psi of boost at sea-level...

I will get the PLX logger file done in the next few days..

Sixline

I see what your saying now....why the hell is my gauge sitting at zero then when the engine is off? Shouldn't it be reading some vacuum at this elevation?

Also, what do you think about E85 with the stock fuel pump and K26/6?

Rogue_Ant

Because your gauge doesn't measure absolute pressure - it measures 'gauge' pressure. Basically it is measuring the pressure in the vacuum/boost line vs the outside. This is also known as differential pressure (the difference between two points of measurement).

If it was an absolute pressure gauge, then you would see the reduced pressure at elevation. This is exactly what the MAP sensor reads (Manifold Absolute Pressure).

The stock pump is adequate for E85 and the K26/6.

Sixline

Sorry, I am not well versed in the different measurements of pressure....thanks for the explanations.

How much boost would you recommend if I run E85 with the stock pump?

refresh951

18 psi was what I ran with the k26/6 and E85.

Dwane

Nothing but praise from me for the products and after sales service.

Sixline

Were you still using the stock fuel pump though? I am also at 5300 feet so I have to work the turbo harder to compensate. Wouldn't the K26/6 be far outside it's efficiency range?

refresh951

Stock pump will be fine with the K26/6 and E85. You will not hold 18 psi to redline but it is still fun in the mid range.

Sixline

Reset the idle this weekend. Didn't seem to really make any difference. Car idles fine.

The 2K RPM hang is only when the car is cold(open loop). It will literally hang for like 30 seconds or more if you let it. Kind of annoying for short trips where the car doesn't warm up.

Rogue_Ant

Your ISV could be sticking, and/or your throttle could stick too.
Can you send me a log of it occurring?