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Mountune Fiesta MRX Turbo

meFiSTo

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MRX turbo hose popped off...

After a cursory search of the web and this forum, I did not find any threads about MRX-upgraded Fiestas having problems with any turbo hoses blowing off in use. At least, not any threads showing an pervasive problem.

I had it happen at a track day Sept. 1 in Portland. It was the elbow hose connecting the turbo outlet to the intercooler charge pipe provided by mountune. I'd reckon this the most likely to pop off in general.





I spent a futile hour or so under the car in the paddock, loosening hoses, etc. to no avail. There was no getting that hose back on in the field for sure. Back at the shop, we determined that, for whatever reason, the elbow was too short (in my situation) and Cantrell replaced it with an elbow that wound up adding about 1-1/2 inches on the hose end attached to the turbo out and about 1 inch to the hose end attached to the fixed position charge pipe. It's a nice fit now (completely snug over the lip and to the end of the collars with a little more room for situational flexing. No changes to the hose connecting the intercooler inlet to the other end of the charge pipe. We also switched to t-bolts that Cantrell uses in its Porsche applications.

I'm done for this season (storm door just opened up here, although this weekend is incredible). I'll be doing fall cleanup and taking hikes/walks on "sunny" days from here on in with my boy, Oscar.

Anyway, I figured I'd share this anecdote.

Hello from Oscar:

 


Last edited:

M-Sport fan

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Oscar does NOT look all too happy about that recalcitrant hose not wanting to stay on the MRX!!!

(But I will bet he IS happy for all of the walks/attention he will be getting now that racing season is over! ;) )
 


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corpus christi
After a cursory search of the web and this forum, I did not find any threads about MRX-upgraded Fiestas having problems with any turbo hoses blowing off in use. At least, not any threads showing an pervasive problem.

I had it happen at a track day Sept. 1 in Portland. It was the elbow hose connecting the turbo outlet to the intercooler charge pipe provided by mountune. I'd reckon this the most likely to pop off in general.





I spent a futile hour or so under the car in the paddock, loosening hoses, etc. to no avail. There was no getting that hose back on in the field for sure. Back at the shop, we determined that, for whatever reason, the elbow was too short (in my situation) and Cantrell replaced it with an elbow that wound up adding about 2 inches on the hose end attached to the turbo out and about 1-1/2 inches to the hose end attached to the fixed position charge pipe. It's a nice fit now (completely snug over the lip and to the end of the collars with a little more room for situational flexing. No changes to the hose connecting the intercooler inlet to the other end of the charge pipe. We also switched to t-bolts that Cantrell uses in its Porsche applications.

I'm done for this season (storm door just opened up here, although this weekend is incredible). I'll be doing fall cleanup and taking hikes/walks on "sunny" days from here on in with my boy, Oscar.

Anyway, I figured I'd share this anecdote.

Hello from Oscar:

When did you purchase your kit? I got mine a few weeks ago and my elbow seems longer than yours. It could just be the angle of the picture though but mine fit perfect. Wonder if they made a change to the elbow?

Edit: Hi Oscar!
 


meFiSTo

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When did you purchase your kit? I got mine a few weeks ago and my elbow seems longer than yours. It could just be the angle of the picture though but mine fit perfect. Wonder if they made a change to the elbow?

Edit: Hi Oscar!
I was among the early implementers. Mountune says no, they only have the original hose. We just got a generic boost hose elbow with about 4 inches of extra hose on both ends, and trimmed and shaved it down to fit such that the hose comfortably covered the collars on both ends. Hopefully, this adjustment and the t-bolt clamps will do the trick. I'll find out next year once I get the car back out for a track day. I suspect the comparatively long duration, repetition and heating of the hoses might make the setup more susceptible to pop off than stock. There is more pressure and it's held throughout WOT. This summer did not go as hoped. I had the shifter linkage at the mountune quick shift block pop off at Portland in August plus the securing bolts all along my exhaust (from turbo back) also loosened to the point that some nuts backed out completely. Ugh. Shop replaced the studs and nuts with more stout material. Nut-and-bolt activity before and after track days us going to have check a lot of stuff every time I suspect.
 


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Corpus Christi
I actually had the exact thing end my day at TWS (luckily toward the end of the day anyhow). The elbow is just barely big enough in my kit, and its very tough to shape it into place. I was able to get it back on, but I had to replace a clamp that I stripped out.
 


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corpus christi
I was among the early implementers. Mountune says no, they only have the original hose. We just got one and trimmed and shaved it down to fit such that the hose comfortably covered the collars on both ends. Hopefully, this adjustment and the t-bolt clamps will do the trick. I'll find out next year once I get the car back out for a track day. I suspect the comparatively long duration, repetition and heating of the hoses might make the setup more susceptible to pop off that stock. There is more pressure and is held throughout WOT. This summer did not go as hoped. I had the shifter linkage at the mountune quick shift block pop off at Portland in August (the securing bolts all along my exhaust (from turbo back) also loosed to the point that some nuts back out completely. Ugh. Shop replaced the studs and nuts with more stout material. Nut and bolts before and after track days are going to have check a lot of stuff every time I suspect.
Yea I have no track experience with this car so that could definately part of the issue. That elbow is a pain in the ass to put on if the charge pipe already bolted down lol. I bet those t-bolt clamp will help a lot, i plan on switching over my clamps to them as well. Glad you got it fixed.
 


antarctica24

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After a cursory search of the web and this forum, I did not find any threads about MRX-upgraded Fiestas having problems with any turbo hoses blowing off in use. At least, not any threads showing an pervasive problem.

I had it happen at a track day Sept. 1 in Portland. It was the elbow hose connecting the turbo outlet to the intercooler charge pipe provided by mountune. I'd reckon this the most likely to pop off in general.





I spent a futile hour or so under the car in the paddock, loosening hoses, etc. to no avail. There was no getting that hose back on in the field for sure. Back at the shop, we determined that, for whatever reason, the elbow was too short (in my situation) and Cantrell replaced it with an elbow that wound up adding about 2 inches on the hose end attached to the turbo out and about 1-1/2 inches to the hose end attached to the fixed position charge pipe. It's a nice fit now (completely snug over the lip and to the end of the collars with a little more room for situational flexing. No changes to the hose connecting the intercooler inlet to the other end of the charge pipe. We also switched to t-bolts that Cantrell uses in its Porsche applications.

I'm done for this season (storm door just opened up here, although this weekend is incredible). I'll be doing fall cleanup and taking hikes/walks on "sunny" days from here on in with my boy,
So when I did mine I had to take the mounting hose that connects directly to the outlet of the turbo and cut it in half because my hot side pipe is 2.5” in diameter, on the end that connects to the turbo outlet I have two clamps holding it. It’s not coming off.
 


antarctica24

Active member
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Pugs. It's a Fiesta thing. Multum in Parvo, Toshi.

Oh, but the fur. Double coats are evil.


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They all fit it depends on how much work your want to do. Mine was a sold pipe from the fmic to the stock turbo. When I went mrx, I had to cut the pipe into 2 piece so I could turn the piece that connected to the turbo.

The kit was made to use part of your factory plumbing.
 


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corpus christi
Well damn, still waiting on my 1st revision. Wonder if I should get the wastegate now and have Randy finish tuning when I put it on. [scratch]
 


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corpus christi
Screw it, I'm holding off for now... The car rips now already. At least now I've got an option for more power later on. Can't wait to see the improvement this has over the stock though!
 




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