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Mountune Fiesta MRX Turbo

danbfree

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Tigard, Oregon, USA
Thanks, I started a conversation with Randy but I think I will wait until the cooler fall temperatures come before I start sending him logs (I haven't paid for his services yet). It's a shame Randy or mountune isn't a vendor on this site, we talk so much about it.
Interesting, I always assumed that he was, it's really too bad as he definitely has great stuff and is a solid tuner... I went through the vendor list and like half I never really heard of before and I have a list of like 2 dozen bookmarks for vendors I use... Well, best of luck to you man, but definitely let him know that your gas is almost certainly 93+, I have had good luck for the last few years with our Premium "92" tuned for 93+ on 3 different DI-T cars and I'm sure you'll see some better results in both lower end feel and upper end pull once dialed in.
 


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Hela
The pulls on Youtube are my car, in Mexico of course. No formal dyno and I dont run WOT in 1st to preserve the axles and side bearings in the transmissions, the known weak points for these cars (aside from leaky axle seals even stock). Vdyno from yesterday, SAE, adjusted for temps and barometric pressure incorporating altitude adjustments are shown here. From real world, closest I can tell you is it runs about a half a car length to 3/4 behind my buddy's from 40-110mph and he has a larger turbo and a true dyno of 305whp/290wtq on pump 93, about 350whp on E40, redlines at 7250. My car is a wee bit lighter, about 100lbs but I kept the rev limiter at 6600, so that accounts for some of the variables. We ran with him at 93 octane and myself at my E22 blend. I would say I safely am at 280-285whp which is great for this little beastie. Youtube videos are about the same temps as our runs fyi. I will say that at below temps in the 60's, the car sometimes nips mid-290's to barely 300whp is the highest I have seen. When you get to 85-100 degrees, vdyno's are in the 270-275 range. Very safe as requested of Randy.

Red (3rd gear) and blue (4th gear) are two days ago runs, as you can see very consistent with a good log. Green is with temps at about 44 degrees a few months ago. The torque is overestimated due to a bit of wheel slip at peak torque for the cold run, but its easily 10hp over what it is right now when you factor out that hump. E22 blend for all the runs, about 94.5 octane, but no additional timing over 93 maps explaining why they arent higher. I just wanted the safety net for knock/etc, fueling is adjusted accordingly. This is on the non-billet WGA fyi. Regarding the weight (asked previously), back seat is out, spare is out, lightweight wheels and brakes, lightweight battery, washer reservoir removed, but intercooler is a bit heavier. Weighed in at 2580 without me in it. I am 175lbs.

Pics.jpg

https://www.youtube.com/watch?v=lf3RDxGcBiI

https://www.youtube.com/watch?v=Yd2hmPfoOB0

https://www.youtube.com/watch?v=uOfj5196CRo
 


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Hela
Great to know thank you! Do you remember your zero'd out WG boost levels?
Sure thing, I kept every log for every revision. These are not distributable per Randy's request to maintain privacy of his tuning strategies, but I can tell you the boost at the rpms below for the first run using the non-billet WGA on wastegate pressure at WOT:

3300rpms - 9.56psi
4000rpms - 11.86psi (peak)
5500rpms - 10.92psi
6400rpms - 10.92psi
 


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Location
Hela
I would note too that I have the Mountune airbox with a 3" bored bottom inlet/3" flange and larger ducting (2.75" neoprene from Summit Racing originally for brake ducts) going into the fender with the washer reservoir out, Whoosh 2.75" induction pipe from airbox to crossover, RAMAIR crossover pipe (2.75"), a 2.75" to 3" aluminum adapter to the 3" turbo inlet elbow. This definitely helped the car spool faster and provided better throttle response. The factory setup with a Mountune airbox has two feeds with the bottom at 2.5" I believe, the factory induction pipe necks to 2.5", the factory crossover goes from about 2.5" to almost 1.75" at the bottom, which goes to an adapter back up to the 3" for the turbo inlet. I was not happy with that, although its designed for plug in play, so i modified the airflow path to ensure it was 2.75" or more all the way with the parts noted. The Mountune airbox isnt a major restriction since it has two feeds already, despite the bottom being 2.5".

I never saw over 282 on the vdyno despite temps in the 40's and 50's until I made these changes, but that was fine since that was the target on 93, give or take a few hp. With the changes, I had one log at 305/308 and repeatable logs in the mid to high 290's, adjusted SAE for temps and barometric pressure by altitude for my location in the 40 degree temps. The car's tuning is designed to be safe though so no amount of airflow mods will change power much when load targets are hit according to the tune when its hotter, you'll just hit them easier. Basically buying more power when its cold and the tune/load targets will allow for it being higher due to the temps being cooler. I didnt ask Randy to push the tune higher in the temp adjustments as I wanted it very safe when its hot out.
 


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Location
Albuquerque
Good info.

Already love mine with stock intake, exhaust and base tune.

Still deciding on an intake to go with the Mountune exhaust and tune going on the car late dec early jan.
 


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Boise
^^^ I have never done a hard launch, no will I ever as I belive this is hard on transaxles.... however, once I get fully tuned and my kinks worked out with boost and tuning, I will get you a rolling launch.

There are few vids on youtube of someone with an MRX doing some 1st-3rd gear WOT pulls. Lastly, I assisted someone recently with an install who said they will get some 1/4 mile times loaded after tuning is complete (I will not state their name in case they do not get the videos loaded).

Like you, I have been very curious as well for some times or slips and yes, I agree too many variables to capture true 0-60's. I just bit the bullet and bought it. Even at 20psi with potential boost leaks, this thing is tons of fun. I do not regret the $2k I spent for the kit.
I was the guy that you helped out I believe. I got the turbo installed finally. Took 3 v-band clamps, the 3rd of which I sourced from an exhaust shop because Mountunes sourced ones were awful. So its up and running, and I will be taking it to the track over the next few months. Need to get tuned first and the next unlimited event at my local strip is in October. So for the guy that keeps asking for times. I will get them for you. I know you have been waiting for forever, but I am running this kit to science it. I will also be taking it to a dyno after tuning where I will pair the new runs up with my stock and stage 3 runs to show actual gains.

FiSTicuffs, I know you asked about WG boost zero'd out, I opted into the upgraded WGA and with my test drives last night I was showing 18.5psi. Hopefully this thing does work once its finished.
 


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Lawrence
Wow thats awesome! May need to buy it now. I have to tear it all apart now because Mountune belives it was set incorrectly from the shop floor. I am topped out at 23.5 psi (should be ~27.5psi). Still a beast though! If I am tearing it down to make the adjustment I will just buy the upgraded WG. FML!
 


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Boise
Wow thats awesome! May need to buy it now. I have to tear it all apart now because Mountune belives it was set incorrectly from the shop floor. I am topped out at 23.5 psi (should be ~27.5psi). Still a beast though! If I am tearing it down to make the adjustment I will just buy the upgraded WG. FML!
Yeah I didnt wanna have to go through and tear it all down, so I just sucked it up. I had read through so many comments earlier in this thread about the WG being the problem, and it didnt seem like most people were going for it. Gotta do the science haha. I will update with Boost numbers as I go through the tuning phase. Hopefully I will see that 27.5 or more if I am lucky. Just on the zero pressure it already feels way strong up top. The AP is showing 211 hp which is higher than I had seen before with stage 3 and tuned on the stock snail. Its got me excited.
 


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Baton Rouge
Edit: mobile phone broke formatting and deleted posts.

Have some logs doing a before and after of the car with the stock intake and a CPE intake with a AEM Dryflo Filter and a K&N Precharger Wrap. I'll format and post the long if anyone cares.

Stock intake is limited to about 23.5 psi @ 95F at 28.5 lbs air/min at redline. This is about 260 Wheel HP at 6.9k RPM. CPE intake with my custom filter and wrap did about 31.5 lbs air/min @ 25-26 psi at redline. This is about 290 Wheel HP at 6.9k RPM.

Mountune's MRX Turbo and Downpipe, FSWERK's 2.5" exhaust, CPE Intake, AEM Dryflo Filter. Also have the upgraded wastegate set to 3-4 mm preload, does about 17-19 PSI on wastegate pressure.
 


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Baton Rouge
Pubic service announcement:

If you are looking at your boost for wategate pressure numbers, you are looking at the MAP. This is the wrong sensor for the car and won't propperly show you what the turbo is doing, since this is in the intake mainfold and past the throttle body. Many tuners use the throttle body for boost control, so if they set the max "low boost" to 15 psi and your wastegate is set to 18 psi, you only see 15 psi of boost. Many people have gotten confused about this in the past, and rereading the thread a few people have gotten butrhurt about swapping in a stiffer wategate and not seeing the wastegate PSI going up. It is just the wrong sensor.

You want the TIP Relative or TIP Absolute in order to get the turbo's output. This sensor in in the cold side air charge pipe after the intercooler and before the air throttle body. This shows you what the turbo is doing after the ~1 psi drop across your intercooler. This is how I knew my turbo was overspooling after I swapped the intake...besides my throttle body stepping in to control boost. The TIP senor is what tuners often use to adjust the wastegate to get the propper turbo PSI output post-intercooler.

I'm doing 3 dyno pulls in the morning for my tuner and testing methanol tomorrow before it gets over 100F outside, so if anyone wants that I can get pictures and format them for a Friday night special post.

If no one want them, I'm lazy and will probably make a thread at some point when I have free time in the next few weeks.
 


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Location
Baton Rouge
Wow thats awesome! May need to buy it now. I have to tear it all apart now because Mountune belives it was set incorrectly from the shop floor. I am topped out at 23.5 psi (should be ~27.5psi). Still a beast though! If I am tearing it down to make the adjustment I will just buy the upgraded WG. FML!
I'd probably set the original mountune's wastegate to like 4-5 mm of preload. I'd do the upgraded wategate to about 3-4mm of preload.

To do the preload on internal wastegate turbos, you remove the retaining C clip and pull off the wategate arm. Loosening the locking nut to about 1/4-1/3 of an inch, or about 1 cm.

You want the arm to where you can slip it on and off VERY snug without stretching the spring at all. This is 0mm of preload. Most turbos won't function right if you have less than 2mm of preload. Now you have to shorten the arm 3-4 mm to set it to the propper preload.

On the mountune's turbo arm this is easy. On the upgraded wategate, each turn of the thread is 1 mm. So, you spin the wastegate arm in the shorter direction (CW or CCW?) 3-4 times, or 6-8 half turns. Now that it is set to 3-4 mm of preload, the hard part is attaching the wastegate arm under spring pressure. Once that is finished, put some anti-sieze on the lock nut and tighten it against the wastegate arm, then put the C clip back on the wastegate nub.

Now reinstall the turbo, since you have to pull the arm off to do the damn thing. Shame the wastegate is between the block and the turbo.
 


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Albuquerque
Need brakes.

This turbo is for people coming from the Evo maybe sti world(never driven one).

It did exactly what I was expecting. My car now is the cousin of my old 03 VIII.

I am still running the base tune and decided to go with Mountune for the tune on a stock intake and exhaust.

Then it’s on to suspension and bracing.

After that an LSD is in the plans

To finish this post

I HIGHLY recommend this turbo kit
 


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Location
Western WA
Was suffering from an exhaust leak which lead me to find this nut freely spinning and almost off:



I know the kit comes with a supplied copper coated nut, I'm trying to figure out if it was used or the factory nut was reused since it is obviously black in color now. Would the copper coated nut change colors over heat/time or should it still be copper-colored? The kit has a little less than a thousand miles on it.
 


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Boise
Bought my mrx kit, how do I get my base tunes to put in my accessport? Didn’t come with any files to download.
You should get an email from Randy with the base tune for the kit. It might take a few days to get tho. If you already have the kit installed I would contact them tomorrow. Otherwise just do the install and wait on the email.

If you havent done the install yet, be carefull with the coolant lines, and make sure your banjo fittings are suuuuper tight. Also do yourself a favor and get the manifold and turbo together with the vband before you put it in the car. I broke 2 vband clamps from Mountune before I went and got a beefy one from an exhaust shop in town. Read the instructions a few times and ensure you do things the way they say. I did a few things out of order and ended up ruining my oil drain pipe as well. As I said before be careful with the coolant lines they are a pain in the ass. Also the instructions say a little coolant will come out, and thats a straight lie. I lost a 1/4 gallon so get something down there to catch it when you pull the lines.

If you already did the install just disregard the majority of this message lol.
 


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Location
Western WA
be carefull with the coolant lines, and make sure your banjo fittings are suuuuper tight. As I said before be careful with the coolant lines they are a pain in the ass.
Is there any concern with tightening it too much since it has that copper washer or crank it as tight as humanly possible?

I'm struggling with this too, I have a little leak from the coolant banjo bolt and it seems like I have to remove that L-shaped oil line with the accordion bend at a minumum (maybe more) just to get enough space to tighten that bolt.
 


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Location
Cincinnati
Is there any concern with tightening it too much since it has that copper washer or crank it as tight as humanly possible?

I'm struggling with this too, I have a little leak from the coolant banjo bolt and it seems like I have to remove that L-shaped oil line with the accordion bend at a minumum (maybe more) just to get enough space to tighten that bolt.
I had one of the coolant fittings come loose over about 20k miles. I ended up replacing the rigid coolant lines with braided steel flex lines from ATP. I managed to remove the Mountune lives and install the new ATP lines without removing the turbo but there is almost no room to work and it requires some creativity.

Also, make sure you use a high temp thread sealant, not thread lock, on the pipe-threaded fittings.
 




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