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Mountune Fiesta MRX Turbo

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Hela
Excellent graph and video Pete, happy for your results. For fun I compared your 50-80mph 3rd gear run here to my 50-80mph 3rd gear run on the X47, they look about identical side to side. So that means you're probably making very close to 300hp.

Are you having a Dyno done at any time?
Thx! Would love to see your vid if posted somewhere? :) Dyno will come but prob be a few before I do, did you dyno yours?
 


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The log I took for the VDyno in 3rd was a pull from 2500 for tuning purposes which bogs it a bit. If you make a pull from 3000rpms or so, it tends to spool around 4k, which is great for traction. In the video though I hit it at like 3800 or more so that was just for sound and needle sweep capture :) Fuel mileage is better than stock, averaging 35mpg if I keep my foot out of it. Here is the brief 4th gear pull I did on a Mexican hwy, for comparison. Definitely makes more in 4th. Not to redline due to not wanting to enter orbit.

View attachment 17361
This is great to hear. I like the graph, I like the fuel savings, I like the talk of traction. AND the numbers are right in the ball park of what I was looking for. That said, I am at 2800' elevation, so I wont get near as good of results but the turbo looks to be solid. I know you are working with Randy, has he said anything about how close this turbo is to maxed out? I assume that the fuel system would reach limits around where youre at, but I may go aux to boost more juice out of it. Just curious how close the turbo is.
 


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Hela
This is great to hear. I like the graph, I like the fuel savings, I like the talk of traction. AND the numbers are right in the ball park of what I was looking for. That said, I am at 2800' elevation, so I wont get near as good of results but the turbo looks to be solid. I know you are working with Randy, has he said anything about how close this turbo is to maxed out? I assume that the fuel system would reach limits around where youre at, but I may go aux to boost more juice out of it. Just curious how close the turbo is.
Randy is a fantastic tuner, just be patient as he does the revisions incrementally to build it up to where it should go. We should have about 2 psi left in the non-billet wastegate actuator since its at 74% WGDC. If you're higher altitude, I would definitely go catless and get the billet wastegate actuator so you can hold more boost. I figure the car is going to peak at 285-290whp or so at 941ft elevation. He hasnt touched spark yet, the numbers and dynos are all with the base spark and nothing added, hence why my logs constantly show the car adding timing through WOT. I'm fine with that though, dont want the car on the ragged edge. The fuel rail pressure increases with RPM and I have no dips so not worried about running out of fuel on my E16 blend. Per Randy, car would need aux fuel to go E30 on the big turbo.
 


jeff

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Thx! Would love to see your vid if posted somewhere? :) Dyno will come but prob be a few before I do, did you dyno yours?
Start the video around 0:57 when I shift into 3rd gear. It's a bit hard to compare because I go WOT in 2nd and then shift to 3rd whereas you just hammer it in 3rd. But if you freeze mine on 0:57 and then watch it and then watch yours you'll get a close comparison. BTW mine is on race gas tune so if I were on the 93 tune the MRX would be quicker in a 4000-redline pull, as would be expected with it's different powerband. At the same time the X47 spools a good bit quicker so all in all I think it would be about even. I posted a V-dyno comparo a few pages ago on this thread I think, I believe they're making similar power, it's all in the curve. In a roll race from 20 to 80 the X47 on 93 would likely pull ahead at first but the MRX would catch up once it hit it's sweet spot.

My car dyno'd at 298/322 on 93+race gas...I didn't do a pump gas run but it should be around 280whp like everyone else.

Start the vid around 0:57 or a bit earlier if you want the whole run.

Happy for you, MRX is a great option!

[video=youtube;8j6yd_FSp9s]https://www.youtube.com/watch?v=8j6yd_FSp9s&t=61s[/video]
 


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Randy is a fantastic tuner, just be patient as he does the revisions incrementally to build it up to where it should go. We should have about 2 psi left in the non-billet wastegate actuator since its at 74% WGDC. If you're higher altitude, I would definitely go catless and get the billet wastegate actuator so you can hold more boost. I figure the car is going to peak at 285-290whp or so at 941ft elevation. He hasnt touched spark yet, the numbers and dynos are all with the base spark and nothing added, hence why my logs constantly show the car adding timing through WOT. I'm fine with that though, dont want the car on the ragged edge. The fuel rail pressure increases with RPM and I have no dips so not worried about running out of fuel on my E16 blend. Per Randy, car would need aux fuel to go E30 on the big turbo.
Yeah definitely had the small increases with revisions when he did mine. I just finished my stock turbo tune about a month ago with him. He did a really good job with what we had to work with. 91 gas here is trash in comparison to other places. No 93, but we do have a single E85 pump in town. I had talked with him about trying to hit 300 on the MRX with my fuel and elevation, he felt I would be closer to 250whp. I do feel like I will be able to get more out of it than that, however its not going to be as easy. I also planned on going with the upgraded WGA that they offer. I will also likely move to aux so I can run E30 tune to try to get the most out of it that I can. There is the new option that Ron@Whoosh is offering on his site, the Peron stage 4 kit. But its a solid almost 5k to get everyhing. And thats a bit steep. So the MRX is likely to remain the choice. But I am so torn cause I want all the things. Your posts have been solid for info tho.[pray]
 


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Hela
Yeah definitely had the small increases with revisions when he did mine. I just finished my stock turbo tune about a month ago with him. He did a really good job with what we had to work with. 91 gas here is trash in comparison to other places. No 93, but we do have a single E85 pump in town. I had talked with him about trying to hit 300 on the MRX with my fuel and elevation, he felt I would be closer to 250whp. I do feel like I will be able to get more out of it than that, however its not going to be as easy. I also planned on going with the upgraded WGA that they offer. I will also likely move to aux so I can run E30 tune to try to get the most out of it that I can. There is the new option that Ron@Whoosh is offering on his site, the Peron stage 4 kit. But its a solid almost 5k to get everyhing. And thats a bit steep. So the MRX is likely to remain the choice. But I am so torn cause I want all the things. Your posts have been solid for info tho.[pray]
Glad to help sir and thx! I would bet you get to 280-290 on the MRX with E30, billet WGA and Aux fuel even at your elevation. I'm about 2000 ft lower than you but I'm on E16, no aux fuel and no billet WGA and it looks like you'd be down about 17whp from where I am at for your 2800' altitude, local barometric pressure and temperature right now in Denver using my log data for power estimates (it shows higher for you in blue since I would need to be making more power to have the same log in your elevation, so subtract that amount from my red line and that would be basically a guesstimate log of power for you with my mods at your area, probably 260-263whp). The billet WGA, E30 and aux fuel should be able to net that much more if not a bit more, also considering I'm not at 27.5psi yet.

3.png
 


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Glad to help sir and thx! I would bet you get to 280-290 on the MRX with E30, billet WGA and Aux fuel even at your elevation. I'm about 2000 ft lower than you but I'm on E16, no aux fuel and no billet WGA and it looks like you'd be down about 17whp from where I am at for your 2800' altitude, local barometric pressure and temperature right now in Denver using my log data for power estimates (it shows higher for you in red since I would need to be making more power to have the same log in your elevation, so subtract that amount from my red line and that would be basically a guesstimate log of power for you with my mods at your area, probably 260-263whp). The billet WGA, E30 and aux fuel should be able to net that much more if not a bit more, also considering I'm not at 27.5psi yet.

View attachment 17363
Im actually in Boise, ID rather than Denver haha. I know the screen name causes confusion, but they are about 2500' higher than me! Current weather and pressure is 46 degrees and 30.25in pressure. But this still leaves me feeling confident about the choice to move to the MRX. The only question being, will I want more later. I wont NEED it...... But I might want it. And this is where I talk myself in circles about what I really want hahaha.
 


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Hela
Im actually in Boise, ID rather than Denver haha. I know the screen name causes confusion, but they are about 2500' higher than me! Current weather and pressure is 46 degrees and 30.25in pressure. But this still leaves me feeling confident about the choice to move to the MRX. The only question being, will I want more later. I wont NEED it...... But I might want it. And this is where I talk myself in circles about what I really want hahaha.
Unless you want a come-from-behind win kind of car with 4500-5k spool, I would say go MRX, definitely get the billet WGA and aux fuel and enjoy the car for sure. Catless is a major boon. I am installing the RAMAIR crossover pipe in a week so I can post a before and after VDyno set. Little known fact, the MRX turbo inlet is 3" but there is a 3" to 2.5" reducer insert from there to the stock turbo inlet pipe. I have no doubt this restricts the breathing a bit. The RAMAIR crossover pipe is 70mm (2.75") mandrel bent so with that I also got a 3" to 2.75" reducer and a 2.75" silicone sleeve to connect them. Basically just helping the turbo breathe a bit better, see what happens. Seems like a small change but the turbo inlet pipe is a bit uneven inside and 2.75" has an area of ~5.94in vs ~4.90in for 2.5", so about 21% better flow throughout, possibly more since the stock turbo inlet pipe is not even 2.5" throughout. Will need to see what i can do for the airbox to crossover pipe since I have a 2016, not convinced the Whoosh fix is 100% effective.
 


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Unless you want a come-from-behind win kind of car with 4500-5k spool, I would say go MRX, definitely get the billet WGA and aux fuel and enjoy the car for sure. Catless is a major boon. I am installing the RAMAIR crossover pipe in a week so I can post a before and after VDyno set. Little known fact, the MRX turbo inlet is 3" but there is a 3" to 2.5" reducer insert from there to the stock turbo inlet pipe. I have no doubt this restricts the breathing a bit. The RAMAIR crossover pipe is 70mm (2.75") mandrel bent so with that I also got a 3" to 2.75" reducer and a 2.75" silicone sleeve to connect them. Basically just helping the turbo breathe a bit better, see what happens. Seems like a small change but the turbo inlet pipe is a bit uneven inside and 2.75" has an area of ~5.94in vs ~4.90in for 2.5", so about 21% better flow throughout, possibly more since the stock turbo inlet pipe is not even 2.5" throughout. Will need to see what i can do for the airbox to crossover pipe since I have a 2016, not convinced the Whoosh fix is 100% effective.
Im running the Cobb intake which has the same fix type as I have a 2017 and its not thrown a code yet. Had it on for a few months and its been solid. I assume that the inlet to Cobb intake should be fine if its got a the piece to mate to it. The only thing left stock bolt on wise for my car is the catback. I did go catted downpipe and depending on the piping from that new GReddy exhaust thats delayed until late April, I may go catless. If the GReddy is a full true 3 inch then I will change. If it tapers down at the flange then I likely wont. Changing the DP on the car is the least fun thing I have done in a long time haha.
 


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Hela
Im running the Cobb intake which has the same fix type as I have a 2017 and its not thrown a code yet. Had it on for a few months and its been solid. I assume that the inlet to Cobb intake should be fine if its got a the piece to mate to it. The only thing left stock bolt on wise for my car is the catback. I did go catted downpipe and depending on the piping from that new GReddy exhaust thats delayed until late April, I may go catless. If the GReddy is a full true 3 inch then I will change. If it tapers down at the flange then I likely wont. Changing the DP on the car is the least fun thing I have done in a long time haha.
Lol, so true!
 


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Hela
E20 fuel blend with tune adjusted accordingly (trims < +10%, FRP is great, AFR spot on) with 93 octane timing map. Officially crossed 300whp on the MRX without resorting to full E30. :) 4th gear pull

12.png
 


CSM

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E20 fuel blend with tune adjusted accordingly (trims < +10%, FRP is great, AFR spot on) with 93 octane timing map. Officially crossed 300whp on the MRX without resorting to full E30. :) 4th gear pull

View attachment 17391
Nice!!!

Side note: I see you are in ATL. I just moved here. Is someone local doing your tunes?
 


Woods247

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Nice!!!

Side note: I see you are in ATL. I just moved here. Is someone local doing your tunes?
He’s tuned by Randy at Mountune. A lot of us in ATL use Brian at JST Performance. He’s tuned many including the MRX.
 


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He also disappeared from social media over some head light scandal.
Seems like a weird reason to disappear? I know he had purchased some custom headlights recently, why does it seem there is always drama around custom headlights?

So I am up to 23psi tuned through Randy but I am still on my snow tires until my new summers come in and I have 0 traction currently :D. 200tw should hopefully fix that.
 


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Hela
Have to insert a plug here for the RAMAIR crossover pipe from Whoosh Motorsports. Fitment was very good and I adapted it for use with the Mountune MRX Turbo (added a 3" to 2.75" reducer for the turbo inlet and a 2.75" silicone hump hose). Cars revs smoother and faster and definitely feels like it picked up throttle response. Attached some pics here of the OEM turbo crossover pipe. It necks down below 2" on the turbo side, vs the 70mm (2.75") consistent inner diameter of the RAMAIR pipe. The MRX turbo inlet elbow is 3" so I was losing about 1" of diameter on the OEM pipe. 7.065" sq in area for the 3" pipe vs 3.14" sq in area for the OEM turbo inlet at the smallest section. Now its much closer, 5.93" sq in to 7.065 sq in, 89% more area than before at the choke point. Woohoo :) Waiting on the Whoosh induction hose to go with my 14/15 evap lines i received from Ford so it will be 2.75" all the way to the Mountune airbox.


Fiesta ST OEM Crossover Pipe (airbox side).jpg

Fiesta ST OEM Crossover Pipe (turbo side).jpg
 




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