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Mountune Fiesta MRX Turbo

jeff

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Sorry man I should be more clear. 26 psi by 4300 tapering to 21 by 6500. Holds 26 till 5500
Cool man that's pretty decent. At what RPM do you reach/stabilize at 25psi with the MRX?
 


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I was reading back through the thread and wanted to comment on your post now that I have this thing installed and on tune 3. I have 177.000 miles on my ride at this point. So a lot of experience on the stock turbo and while I am not a turbo expert I can comment on the ride. I also want as a reminder to put in perspective remember I have owned both a 800 and 1000 hp street Pontiacs and a 300/300 Fiero. So relative. As I have been driving around on this for a couple of weeks the instant take off or lack therof in which you speak is not as separate as you describe. My part throttle is insane compared to what the stock turbo felt like.
Thanks for sharing, this is the kind of info I've been looking for.

How would you say the car feels rolling on the throttle in 2nd or 3rd in the 2500-3500 range? I love the way my stock car feels moving around in traffic, but once you get out of that initial surge... Well, it leaves a good bit to be desired.
 


antarctica24

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Thanks for sharing, this is the kind of info I've been looking for.

How would you say the car feels rolling on the throttle in 2nd or 3rd in the 2500-3500 range? I love the way my stock car feels moving around in traffic, but once you get out of that initial surge... Well, it leaves a good bit to be desired.
I live in Spokane Wa. The speed limit leaving my house is 30mph. It is 30mph all the way to work downtown. This turbo is not grabby. You can drive it just like you can your stock turbo. If I want to pass someone on a road that is 45-50mph you can roll your foot into it as you 2500-3500 or aggressively go pat throttle and bring up the power enough to pass without leaving a smoke trail if you get my point. I am not a power monger, but I love power. This is what ford should have given us. It is not a 2860 over the top. People get so hung up on their car needing to make that really high power number and it's not necessary to make this powerful and still be fun hopping around town, or scorching it on back roads which i will be testing out a 2nd time more throughly Saturday and I will report my findings but as I expect it will be a lot of fun. Some say it pulls like a freight train and that is not accurate as a train goes to move its slow and you can drive this at 25mph in 4th or 5th. It's more like a jet ski. You can part throttle it and pull into a dock or you put your finger all the way and leave a rooster tail 10 feet high and their is a lot of variation possible inbeteeen. I really want to share some boost numbers compared to rpm but I promised I wouldn't until randy was done. Jeff and I will be sharing some comparison numbers later on between the Mountune and x47 and x47r so maybe that will help.

I like the word ballistic because at wot throttle you are kind of overwhelmed by what's happening compared to stock. It's like you fire your grandfathers .22 for the firt time then your very next gun is a lapuaat wot the first time. If your a Star Trek fan and you watch the movie generations where Cochran files the first warp ship at the end of the movie. When he brings it on the look on his face when it hits warp 1 is a good representation of what my 2nd tune felt like at wot the first time. Now that I'm getting used to it the look on my face at wot is like the road runner with my tongue hanging out.
 


Butterybunz

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I was reading back through the thread and wanted to comment on your post now that I have this thing installed and on tune 3. I have 177.000 miles on my ride at this point. So a lot of experience on the stock turbo and while I am not a turbo expert I can comment on the ride. I also want as a reminder to put in perspective remember I have owned both a 800 and 1000 hp street Pontiacs and a 300/300 Fiero. So relative. As I have been driving around on this for a couple of weeks the instant take off or lack therof in which you speak is not as separate as you describe. My part throttle is insane compared to what the stock turbo felt like. Everyone here has a turbo in their car and has their own opinions and for me to say their is no lag would be a lie. But the difference is very very small compared to stock. Opinions are relative right? That's my opinion. If I was in 1st gear and put my foot down moving it ever so slowly I would notice the lag. What this turbo does is allow me to get moving and by doing so it reduces wheel spin. More on displacement below. Now, that is an overstatement as if you do not manage it with your foot even with traction control on you will blow the tires off in 3rd gear which I did this morning. I was asked not to reveal any numbers until the tune was complete but this mornings run was at 5:30 at 54 degrees. I'll let you just ponder that. The car is ballistic. I'm certain you all get that feeling with any turbo upgrade over 300, but the curve on this is so nice and smooth. Their is nothing erratic about it. I am so very pleased. I was a huge fan of the stock turbo on the ots Cobb stage 3 tune. Yeah I know right? Even with the minuscule amount of what you call lag, this is really in my opinion what this car should have been from the factory.

I stand by what I have said earlier. You can make anything go 500hp with enough money. This car making over 350 dare I say, 330 is more than you would ever need. If you need more you need more car. I mean it. Chassis design is something I understand and while you can do more in the car I think your pushing the physical envelope and reliability is out the window. Let's not argue about it their are plenty of people making 320+ that doesn't mean they should and it doesn't mean their not on the bleeding edge of reliability and safety. I know we have a focus st clutch and focus st axles but you have to take into consideration linear motion and the forces placed on the chassis under acceleration and deceleration cornering and braking and weight transference.

The other thing I noticed is that the spool down is slower than stock. Meaning as you approach red line to go from 1-2 2-3 3-4 4-5 under hard acceleration on the stock turbo it seemed like the rpm went down quicker where as this holds rpm longer.

You might want the hybrid if you were racing all the time on a road course because coming out of a turn the hybrid may give you an advantage, but based on my boost level and lbs of air moved versus with what I'm seeing, with the hybrid your not going to hold the lead in the straight away. You might pull off an 1/8 mile upset but not the 1/4. As a stout 1/4 mile guy I would be willing to bet this is the case of all the bigger non hybrid turbos. This turbo is making more boost than the reported hybrids so far based on the little access port and for much longer than the hybrids.

Now for displacement. This turbo is. Egging for a larger displacement motor. It could be a modified 1.6 to 1.8, it could be a 2.0 or a 2.3 ecoboost truxk motor. A little normally aspirated low end torque fro a larger displacement motor and this turbo it would be insane. The possibility exist to take the stock turbo and this turbo and do a compound setup(I'm still contemplating) but I think the bigger motor makes more sense. I guess we will see in April 2018.

Not trying to upset anyone here just giving my opinion based on my Mountune install. Let me say it again. I am so very happy with this turbo and would highly recommend it to anyone wanting to spend the least amount of money for the biggest bang for your buck from the most reputable company supporting our vehicle. It doesn't matter if it is a Garrett with Mountune's name on it. In my opinion if Mountune decided to put their name on it that made it worth it because they felt it met their standards. That they upgraded the turbine, if it was 5 blades or 20 blades who cares if the turbo is doing what they say it does, then it's worth it and it does more than what they say it does.

And as for the wastegate not changing it out. It is so not necessary. If I do anything else power wise this year it will be to install either or both a dei cro2 fmic sprayer, meth/water injection 8" before the throttle for safety.

I may have randy do a tune for race gas which I can get here easily for a drag day here and there.

This turbo is like buying a brand new car.
Since this is my post you are quoting I feel inclined to reply. I'm glad you like the MRX and are enjoying it.

Some of your claims aren't true about it having better top end than a hybrid or that the lag is basically the same as a stock turbo. If you like the power band the MRX provides, more power to you.

The reason the Fiesta ST is so fun, in my opinion, is the down low torque it makes from a small displacement turbo. The small turbo, like you said, allows you to burst out of corners... which is wonderful for AutoX and Road Course. Which is where the Fiesta ST shines, not the drag strip. That being said, the hybrid turbos make the same or more power as your MRX..

Here's why I love the hybrid turbos:

Dyno directly from Pumaspeed
See the red box? That huge burst of torque is magical, peaking around 3,500 rpms. Also notice the power is never dropping off, building all the way to redline.

Now the MRX:

Dyno directly from Mountune
See the red box? Peak torque isn't achieved until 5000rpm.

It's hard to compare dynos, so I used the ones directly from the manufactures (typically the most generous dyno sheets).

Different strokes for different folks.
 


jeff

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Since this is my post you are quoting I feel inclined to reply. I'm glad you like the MRX and are enjoying it.

Some of your claims aren't true about it having better top end than a hybrid or that the lag is basically the same as a stock turbo. If you like the power band the MRX provides, more power to you.

The reason the Fiesta ST is so fun, in my opinion, is the down low torque it makes from a small displacement turbo. The small turbo, like you said, allows you to burst out of corners... which is wonderful for AutoX and Road Course. Which is where the Fiesta ST shines, not the drag strip. That being said, the hybrid turbos make the same or more power as your MRX..

Here's why I love the hybrid turbos:
...That huge burst of torque is magical, peaking around 3,500 rpms. Also notice the power is never dropping off, building all the way to redline.

Now the MRX:
...See the red box? Peak torque isn't achieved until 5000rpm.

It's hard to compare dynos, so I used the ones directly from the manufactures (typically the most generous dyno sheets).

Different strokes for different folks.
GREAT post. This details alot of why Bryan and I are discussing seeing that we have these 2 contrasting turbos.

You pretty much hit the nail on the head about the differences. With my X47 I hit 25psi at 3,400rpms and hold there until about 6,000rpms. The MRX has more but it comes in later. Just like your graphs demonstrate.

I will say that the Puma dyno is BS on the 47 though. I've researched it extensively, people are uniformly getting 275-280 on pump gas with the basic X47 (not + or R). Even Puma says that the 300+ figure is with e30.

Quote from Puma website:
The brief was very simple, create a higher flowing stock frame charger that could crack the 300+whp (E-Fuels) barrier whilst still delivering proven reliability....
The new turbo has the ability to spool to 14 PSI at 1800 revs and to full Boost as low as 2200 revs,it will continue to flow and make power to just over 7500, that's a huge 5000 wide band of sheer pleasure.


I also think that the "full boost at 2200" is BS, FWIW.

I do suspect the MRX has a bit better top end than the hybrids.

Both are great turbos. It's all about where you want the power band.
 


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Butterybunz

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GREAT post. This details alot of why Bryan and I are discussing seeing that we have these 2 contrasting turbos.

You pretty much hit the nail on the head about the differences. With my X47 I hit 25psi at 3,400rpms and hold there until about 6,000rpms. The MRX has more but it comes in later. Just like your graphs demonstrate.

I will say that the Puma dyno is BS on the 47 though. I've researched it extensively, people are uniformly getting 275-280 on pump gas with the basic X47 (not + or R). Even Puma says that the 300+ figure is with e30.

Quote from Puma website:
The brief was very simple, create a higher flowing stock frame charger that could crack the 300+whp (E-Fuels) barrier whilst still delivering proven reliability....
The new turbo has the ability to spool to 14 PSI at 1800 revs and to full Boost as low as 2200 revs,it will continue to flow and make power to just over 7500, that's a huge 5000 wide band of sheer pleasure.


I also think that the "full boost at 2200" is BS, FWIW.

I do suspect the MRX has a bit better top end than the hybrids.

Both are great turbos. It's all about where you want the power band.
True about the numbers on the graphs, which is why I didn't mention them. I was using them to just simply look at the power & torque curves. I've seen dozens of hybrid dyno sheets, power ranges from 260whp to 300whp depending on the type of fuel. We are all limited by the stock fuel system at that point. I've seen about a handful of MRX dyno sheets and they too range from 260-300whp depending on fuel. It's all about how you like your power to come on at this point.
 


M-Sport fan

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GREAT post. This details alot of why Bryan and I are discussing seeing that we have these 2 contrasting turbos.

You pretty much hit the nail on the head about the differences. With my X47 I hit 25psi at 3,400rpms and hold there until about 6,000rpms. The MRX has more but it comes in later. Just like your graphs demonstrate.

I will say that the Puma dyno is BS on the 47 though. I've researched it extensively, people are uniformly getting 275-280 on pump gas with the basic X47 (not + or R). Even Puma says that the 300+ figure is with e30.

Quote from Puma website:
The brief was very simple, create a higher flowing stock frame charger that could crack the 300+whp (E-Fuels) barrier whilst still delivering proven reliability....
The new turbo has the ability to spool to 14 PSI at 1800 revs and to full Boost as low as 2200 revs,it will continue to flow and make power to just over 7500, that's a huge 5000 wide band of sheer pleasure.


I also think that the "full boost at 2200" is BS, FWIW.

I do suspect the MRX has a bit better top end than the hybrids.

Both are great turbos. It's all about where you want the power band.
From your personal experiences with this hybrid; Do you sense that the "makes power to just over 7500 revs" quote above is also BS? [dunno]
 


antarctica24

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Since this is my post you are quoting I feel inclined to reply. I'm glad you like the MRX and are enjoying it.

Some of your claims aren't true about it having better top end than a hybrid or that the lag is basically the same as a stock turbo. If you like the power band the MRX provides, more power to you.

The reason the Fiesta ST is so fun, in my opinion, is the down low torque it makes from a small displacement turbo. The small turbo, like you said, allows you to burst out of corners... which is wonderful for AutoX and Road Course. Which is where the Fiesta ST shines, not the drag strip. That being said, the hybrid turbos make the same or more power as your MRX..

Here's why I love the hybrid turbos:

Dyno directly from Pumaspeed
See the red box? That huge burst of torque is magical, peaking around 3,500 rpms. Also notice the power is never dropping off, building all the way to redline.

Now the MRX:

Dyno directly from Mountune
See the red box? Peak torque isn't achieved until 5000rpm.

It's hard to compare dynos, so I used the ones directly from the manufactures (typically the most generous dyno sheets).

Different strokes for different folks.
im at a disadvantage. I can't share anything number wise and I can only compare what I know. Not having a x47 my stock turbo was running around 230hp and 280tq on real dyno jet numbers not vdyno and I can tell on any road course, any road, any other planet this car now with this turbo would win any situation any time any where against my stage 3 stock setup. I will be any amount of money you want to put down. I'm just saying. Dunks are nice they give you feed back on what your car is doing. I would not trust anything th vdyno says and this turbo is making more power than Mountune is advertising.
 


KnockOff

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I like the mrx but im realistic about my expectations.

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TyphoonFiST

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I got Barry Garcia in a pouch man....scarface got a dog !

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Butterybunz

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im at a disadvantage. I can't share anything number wise and I can only compare what I know. Not having a x47 my stock turbo was running around 230hp and 280tq on real dyno jet numbers not vdyno and I can tell on any road course, any road, any other planet this car now with this turbo would win any situation any time any where against my stage 3 stock setup. I will be any amount of money you want to put down. I'm just saying. Dunks are nice they give you feed back on what your car is doing. I would not trust anything th vdyno says and this turbo is making more power than Mountune is advertising.
I agree that the MRX makes way more power than a stock turbo. I don't think that was ever the question.
 




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