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Which turbo gives best bang for the buck?

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#61
X47R, E50, throttle body aux fuel, ported manifold, forged pistons and rods.

The MRX has the same peak hp capability as the hybrids (~320whp with ethanol and aux fuel) but has way more lag. I believe it's laggier than the gen2 2860r and spools a little quicker than the gen2 2867r.

When you factor in area under the curve or average torque north of 2.2K rpm, it doesn't compare well to the hybrid solution.

In summary it's not a bad turbo, it just doesn't make sense compared to the competition.

Update:
I am looking to upgrade the turbo so I can make closer to 375whp (S280, Gen 2 2860r & 2867R); so I am not beholden to the X47R
I don’t care what turbo anyone installs on their car. I wanted my car to be responsive down low and be fast to redline. Mission accomplished and I recommend what I did to anyone looking for the same. I pedal it minimally to get off the line. Other than that the car is ready to go once it’s rolling past 5 mph. Zero lag.
 


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Tucson
#62
I don’t care what turbo anyone installs on their car. I wanted my car to be responsive down low and be fast to redline. Mission accomplished and I recommend what I did to anyone looking for the same. I pedal it minimally to get off the line. Other than that the car is ready to go once it’s rolling past 5 mph. Zero lag.
Totally agree. Be it the MRX, hybrids, or GTX solutions...they are all much better than the turbo solution that came with the car from the factory. As a newer car guy, I just wish I had a better idea on what kind of power I wanted in a daily driver...as 300whp ish has me wanting more.
 


TyphoonFiST

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Rich-fizzield
#63
Totally agree. Be it the MRX, hybrids, or GTX solutions...they are all much better than the turbo solution that came with the car from the factory. As a newer car guy, I just wish I had a better idea on what kind of power I wanted in a daily driver...as 300whp ish has me wanting more.
I thought you said you had an x47r...forged rods....pistons etc?
 


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Location
Tucson
#64
I thought you said you had an x47r...forged rods....pistons etc?
Yeah I do. I only replaced the pistons and rods after the piston in cylinder 1 failed; The car doesn't need forged pistons and rods with a hybrid...only did it because if I was going to do all the work myself, why would I replace it with stock parts. I said 300whp ish as the car performs quite different based on the ambient temps. For example when it was 60f in Tucson Arizona the car was doing 32+ lbs of air / minute; now that it is 110f the car is doing 29 lbs of air/ minute. Any questions?
 


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#70
High psi with stock manifold equals exhaust gas reversion which equals melted, cracked pistons or popping the deck. Port matching helps but Ron’s extrude honed manifold is the way to go. If air is going in fast it must have a way to go out fast post combustion or kaboom
 


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Tucson
#74
Ouch! Looks like a classic ring failure - the stock ring gaps are tight and when the rings get hot they expand, close the gap, buckle, and pop a chunk out of the piston. Were you able to save the block? Complete short block rebuild?
Cylinder walls were fine and within tolerance. The engine only had 36K on it, so there was minimal wear.
 


Se7eN

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Location
San Juan, Puerto Rico
#75
X47R, E50, throttle body aux fuel, ported manifold, forged pistons and rods.

The MRX has the same peak hp capability as the hybrids (~320whp with ethanol and aux fuel) but has way more lag. I believe it's laggier than the gen2 2860r and spools a little quicker than the gen2 2867r.

When you factor in area under the curve or average torque north of 2.2K rpm, it doesn't compare well to the hybrid solution.

In summary it's not a bad turbo, it just doesn't make sense compared to the competition.

Update:
I am looking to upgrade the turbo so I can make closer to 375whp (S280, Gen 2 2860r & 2867R); so I am not beholden to the X47R
I've run against various Hybrids, (S242, Whoosh Hybrid and Home made Hybrids) and GTX2860r. While running pump gas tunes they all make similar power. It all boils down to driving. Lets face facts, you're never going to be roll racing anywhere lower then 3,000rpm in the streets(of Mexico) and with brake boost it takes all that lag away. Haven't lost to a hybrid yet in equal terms, (Pump gas tunes). MRX is not for everyone but it is fun and mine was extremely low cost to me, so I don't mind it one bit.

On a Side note, if I ever wanted more I'd just go GTX.
 


Last edited:

jeffreylyon

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#76
Cylinder walls were fine and within tolerance. The engine only had 36K on it, so there was minimal wear.
This might be a dumb question - did you remove the engine, pop the heads, and work with the engine on a stand or were you able to just drop the sump and replace the pistons and rods from the bottom?
 


ron@whoosh

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#77
I don’t care what turbo anyone installs on their car. I wanted my car to be responsive down low and be fast to redline. Mission accomplished and I recommend what I did to anyone looking for the same. I pedal it minimally to get off the line. Other than that the car is ready to go once it’s rolling past 5 mph. Zero lag.
this should make some people happy https://whoosh-motorsports.myshopif...sta-st-mrx-turbocharger-upgrade-free-shipping
 


ron@whoosh

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#79
Lol did you just add that??
We are now an authorized Mountune dealer. The small bits we had before were purchased through Ford, now we are direct. All of their Fiesta parts will be on the site soon. As of today, we have about a dozen items
 




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