Mountune Fiesta MRX Turbo

[M-Sport fan]

I know nothing about drag racing, nor care about drag racing to be honest. All we build here are high hp street cars so they need to work everywhere and on stiff suspensions and r-compound tires with low profiles, have to have huge cornering grip, great braking and be able to do a decent street launch, but be able to hook a maximum amount of power always, but more keyed to normal street driving and higher speed races where a full on drag launch is never used.

Powerband is all that matters, as well as keeping a torque level that can be handled. the cars you are referring to that are "slow" are just making too much midrange power in too low a gear to have traction, then too low a redline so they can't utilize that torque to make any hp. If that car is only making 350whp from 350wtq it is wasting its potential. The only time you need all of that power is while racing, so it means that you only need full power in the last 1000-1500rpm. If a car is making "square" power it means that it has a low redline and power is falling so when you are racing you are accelerating a diminishing powerband. So that car is only accelerating like an average 300whp. The byproduct of a torque curve that is dropping is that acceleration g's are also falling the higher it revs which means the rate of acceleration is slowing.

I have some friends with high hp fwd cars that are very driveable, hook the power decently, and make between 600-1150whp on a few different platforms. The key is 8500-10,000rpm redline, flat torque curves, in some cases boost by gear if the turbo is small enough to make full torque in the lower gears, and tuning to allow the cars to be very responsive so that wheelspin can be managed. As in running a peak of 700+wtq through 225 width tires and being able to out-launch gtr's, r8's, gallardos, etc... So it's all possible, but requires the right decisions, making the right compromises, and having a tuner and builder that fully understands it.

OK, but can those buddies also still go around turns with suspensions which can still utilize all of that power, as even the 'roll' races which you refer to (and I will NEVER do myself, NOT even in "Mexico") STILL require a drag type suspension/adjustments to compensate for the FWD, in order to keep from going up in tire smoke once that big power 'hits'.

It just seems pointless to me to have stupid big power (like over 400 to the wheels) in a FWD platform (yes, even all power band 'nannied' by a tuner), unless it is just for dyno queen 'bragging rights', or to try to do the ricer neener neener thing against the RWD V8s they despise with an overwhelming passion.
(Or unless one is insistent on doing the FWD import drag racing thing, which I would not care about EVEN IF they were doing low 5s in the quarter! LOL)
Just get a RWD platform already, and go to an import nameplate if one's a JDM YO-YOer who HATES ON the domestic ones soooo much.

In any case, like was mentioned above, until MUCH stronger gearboxes are made for these cars, it may be a moot point anyway, as much over 400 or so will eat our current transaxles for a snack, regardless of where that power comes on.

 

[blurred]

OK, but can those buddies also still go around turns with suspensions which can still utilize all of that power, as even the 'roll' races which you refer to (and I will NEVER do myself, NOT even in "Mexico") STILL require a drag type suspension/adjustments to compensate for the FWD, in order to keep from going up in tire smoke once that big power 'hits'.

It just seems pointless to me to have stupid big power (like over 400 to the wheels) in a FWD platform (yes, even all power band 'nannied' by a tuner), unless it is just for dyno queen 'bragging rights', or to try to do the ricer neener neener thing against the RWD V8s they despise with an overwhelming passion.
(Or unless one is insistent on doing the import drag racing thing, which I would not care about EVEN IF they were doing low 5s in the quarter! LOL)
Just get a RWD platform already, and go to an import nameplate if one's a JDM YO-YOer who HATES ON the domestic ones soooo much.

In any case, like was mentioned above, until MUCH stronger gearboxes are made for these cars, it may be a moot point anyway, as much over 400 or so will eat our current transaxles for a snack, regardless of where that power comes on.

These are just daily driven cars, sometimes used as winter beaters in the snow... Yes, they can corner, they are designed to work on the street as a normal car, or on the circuit if necessary. They have very stiff suspensions that would be more suitable on a race car and nothing is set up for drag racing. We all love to have fun in the corners at high speed and hate making compromises so handling, grip, and braking is paramount as well as good stability at 200+mph so no drag radials or drag slicks/suspension would work.


You mention gearbox, but they are limited by torque, not horsepower. So if they can handle 350wtq you can still make well over 500whp in a fiesta as long as you don't exceed the torque limits. The other benefit is you don't have to run a crazy clutch which can create a lot of transmission issues.

 

[STAZ15]

OK, but can those buddies also still go around turns with suspensions which can still utilize all of that power, as even the 'roll' races which you refer to (and I will NEVER do myself, NOT even in "Mexico") STILL require a drag type suspension/adjustments to compensate for the FWD, in order to keep from going up in tire smoke once that big power 'hits'.

It just seems pointless to me to have stupid big power (like over 400 to the wheels) in a FWD platform (yes, even all power band 'nannied' by a tuner), unless it is just for dyno queen 'bragging rights', or to try to do the ricer neener neener thing against the RWD V8s they despise with an overwhelming passion.
(Or unless one is insistent on doing the FWD import drag racing thing, which I would not care about EVEN IF they were doing low 5s in the quarter! LOL)
Just get a RWD platform already, and go to an import nameplate if one's a JDM YO-YOer who HATES ON the domestic ones soooo much.

In any case, like was mentioned above, until MUCH stronger gearboxes are made for these cars, it may be a moot point anyway, as much over 400 or so will eat our current transaxles for a snack, regardless of where that power comes on.

That’s the beauty about modding cars though. No one really has to conform to one specific build or another. If someone wants to build a monster fiesta and shred axles like butter well then more power to them!

I personally get satisfaction when someone asks me “ holy crap that’s a fiesta?!” One of the main reasons why I haven’t went with a RWD muscle car or the latter. Heck I would love to build a RWD monster one day too! *sigh* maybe someday when the money is flowing like the river nile.


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[thePete]

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[PearlGreenNMean]

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Welcome back Pete! And all the [emoji90] that doesn't really matter! Lol

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[XLR8]

Sorry if I missed it, but any V-dyno/dyno numbers with the billet wastegate? "Holy balls" should have a measurable jump.

Thanks

 

[pelotonracer2]

You'll have to prove this one. Sorry, but that's not something that can be taken without credit. I revved my 2.4 4g69 to 7k, but that's because it's proven to. The 1.6 in these fiestas are a little newer.

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My Rev limit is 7000 rpm. The Cobb OTS stage 1 tune redline is set at 7200. With better flowing turbo, you are leaving/wasting a lot by having a 6600 rpm rev-limit. On a completely stock car I realize it wouldn't make much difference as it completely runs out of steam. However if you look at *ALL* the dyno runs from people with hybrid turbos, it isn't just peak power but the power gained UNDER the curve. For instance, while my car is currently stage 3+, it makes a whopping 52hp more than stock at red line. It still has a taper down powerband (as the efficiency of the stock turbo sucks) BUT you can actually rev it out without having to shift at 5500 rpms like the stock powerband. You'd be much better off setting rev-limit to at least 7000 rpm.

 

[pelotonracer2]

Mountune Mrx turbo upgrade with billet wastegate
Mountune turbosmart bov
Cp-e cai
Depo racing intercooler
Depo racing catted dp
Thermal r&d exhaust
Denso itv22 plugs
93 octane fuel
70 degrees F
25.6 psi

According to your V-dyno, hp is still climbing at redline. I would definitely set rev limiter to 7000-7100 rpm

 

[pelotonracer2]

The issue with stock fuel system guys is that we tap out at a certain HP, no matter what you rev to. The engine may definately be able to spin up to those rpm's like Koozy's very nice graph shows, but not on the stock fuel system alone. This is why im so anxious for stratifieds new aux fuel system. Pricey, but worth it in every way.

The stock fuel system handles up to 300hp @ the wheels. Sometimes a tad bit more, sometimes a bit less, but right around there.

 

[PearlGreenNMean]

My Rev limit is 7000 rpm. The Cobb OTS stage 1 tune redline is set at 7200. With better flowing turbo, you are leaving/wasting a lot by having a 6600 rpm rev-limit. On a completely stock car I realize it wouldn't make much difference as it completely runs out of steam. However if you look at *ALL* the dyno runs from people with hybrid turbos, it isn't just peak power but the power gained UNDER the curve. For instance, while my car is currently stage 3+, it makes a whopping 52hp more than stock at red line. It still has a taper down powerband (as the efficiency of the stock turbo sucks) BUT you can actually rev it out without having to shift at 5500 rpms like the stock powerband. You'd be much better off setting rev-limit to at least 7000 rpm.

A higher rev limiter will almost always improve time as well, because it delays shifting. I agree. I just didn't know if it was safe or tried and trusted.

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[molten16st]

According to your V-dyno, hp is still climbing at redline. I would definitely set rev limiter to 7000-7100 rpm

This was a real dyno. The graph ended at 6200 which is before red line. Red line is set at 6600. You have no idea what happened after the graph ended so you are just making assumptions. I will leave my redline right where it's at because I trust my tuner and he said power was falling off. You may set your redline as high as you would like on your car. Thanks for your opinion. I'm not being a dick btw. ☺

 

[pelotonracer2]

This was a real dyno. The graph ended at 6200 which is before red line. Red line is set at 6600. You have no idea what happened after the graph ended so you are just making assumptions. I will leave my redline right where it's at because I trust my tuner and he said power was falling off. You may set your redline as high as you would like on your car. Thanks for your opinion. I'm not being a dick btw. ☺

My bad about the dyno... but why on earth would the graph cease at 6,200 rpm??? LOL. Why would your tuner let off at 6,200 instead of running the engine into the rev-limiter? Your dyno graph just shows peak power and nothing else compared to stock.

Looking at *YOUR* graph, power is still climbing when it shuts off at 6,200 rpm. This is visible to anyone who knows how to read a dyno chart. You do understand how these curves work, right? ~grins~. I'm not just interested in peak power but also "power under the curve" compared with the stock turbo. For instance, with my stage 3 set up I am making 52 more horsepower at 6,200 rpm than I did when I was stage 1. That is considerable, just as making an additional 30+ hp is at red line. I can understand shifting early with the stock turbo, but not on a hybrid.

It appears that your tuner has a built in fail safety net by telling you to shift early (and letting off on the dyno at 6,200 rpm). Could you tell me who your tuner is so I can avoid him like the plague? lol

 

[Bretley]

My bad about the dyno... but why on earth would the graph cease at 6,200 rpm??? LOL. Why would your tuner let off at 6,200 instead of running the engine into the rev-limiter? Your dyno graph just shows peak power and nothing else compared to stock.

Looking at *YOUR* graph, power is still climbing when it shuts off at 6,200 rpm. This is visible to anyone who knows how to read a dyno chart. You do understand how these curves work, right? ~grins~. I'm not just interested in peak power but also "power under the curve" compared with the stock turbo. For instance, with my stage 3 set up I am making 52 more horsepower at 6,200 rpm than I did when I was stage 1. That is considerable, just as making an additional 30+ hp is at red line. I can understand shifting early with the stock turbo, but not on a hybrid.

It appears that your tuner has a built in fail safety net by telling you to shift early (and letting off on the dyno at 6,200 rpm). Could you tell me who your tuner is so I can avoid him like the plague? lol

Are you a tuner?? Randy has 38k miles (at 39k) of trustworthy tunes on my car. He is making the most power safely without stressing the hpfp too much. More rpm is more power is more fuel. Randy doesn't tune your car to blow up, he makes them fast and reliable. But you seem like the terminator type, "can't be reasoned with, can't be talked to." Lol I'm jk

 

[pelotonracer2]

Are you a tuner?? Randy has 38k miles (at 39k) of trustworthy tunes on my car. He is making the most power safely without stressing the hpfp too much. More rpm is more power is more fuel. Randy doesn't tune your car to blow up, he makes them fast and reliable. But you seem like the terminator type, "can't be reasoned with, can't be talked to." Lol I'm jk

Actually yes (but not for this platform). I wrote a completely custom map for my Mazdaspeed 3 using the Cobb Race interface, so I do know a thing or two about how it works. I also built National and World title race engines for 15 years (different industry, but an engine is just an air pump so it is all relative). I am a mechanical engineer, not some yoyo kid. I have 23,000 miles on my FiST from "another" Ford tuner (both E30 and 93 maps) and 43,000 miles on the car and it's never been in the shop except for the HVAC flapper issue.

My point is looking at molten16st's map only tells half a story... (and not a great one at that since much information is missing). The curves are incomplete. From what he posted, at 6,200 rpm horsepower is still climbing. If it is dropping off drastically after that to a redline of 6,600 rpm, either something is wrong with his car or....

I realize there is a lot of "tuner worship" and lots of faithful followers of all of them here. I just find posts like this somewhat amusing.

As for rpm and rev-limits, we had these discussions many years ago on this forum. I have no idea what you are talking about when you say "more rpm is more power is more fuel". Rpm limits are are designed around certain parameters, usually crank speed and valvetrain, not to mention torsional stress percentages (you know that thing called twist). Adding a % of rpm also adds torsional stress and ALL motors have their limits. Some applications even have rpm windows to avoid (I forget what that window is for the 1.6L ecoboost, I can't remember but 7350 sounds familiar). This motor will however spin just fine to 7,000-7,200 rpm RELIABLY with a lot more power than you guys are making with a hybrid. That's not my opinion, or some assumption. Many tuners have done so for a few years now. I am not some noob talking out his lol

To be honest, I took a long break from the Fiesta community. I don't know much about Randy or what he does (or doesn't do). I've only heard good things about him actually, HOWEVER, and this is just my honest opinion, I myself would not send out partial dyno graphs like that for public consumption.

 

[Bretley]

Actually yes (but not for this platform). I wrote a completely custom map for my Mazdaspeed 3 using the Cobb Race interface, so I do know a thing or two about how it works. I also built National and World title race engines for 15 years (different industry, but an engine is just an air pump so it is all relative). I am a mechanical engineer, not some yoyo kid. I have 23,000 miles on my FiST from "another" Ford tuner (both E30 and 93 maps) and 43,000 miles on the car and it's never been in the shop except for the HVAC flapper issue.

My point is looking at molten16st's map only tells half a story... (and not a great one at that since much information is missing). The curves are incomplete. From what he posted, at 6,200 rpm horsepower is still climbing. If it is dropping off drastically after that to a redline of 6,600 rpm, either something is wrong with his car or....

I realize there is a lot of "tuner worship" and lots of faithful followers of all of them here. I just find posts like this somewhat amusing.

As for rpm and rev-limits, we had these discussions many years ago on this forum. I have no idea what you are talking about when you say "more rpm is more power is more fuel". Rpm limits are are designed around certain parameters, usually crank speed and valvetrain, not to mention torsional stress percentages (you know that thing called twist). Adding a % of rpm also adds torsional stress and ALL motors have their limits. Some applications even have rpm windows to avoid (I forget what that window is for the 1.6L ecoboost, I can't remember but 7350 sounds familiar). This motor will however spin just fine to 7,000-7,200 rpm RELIABLY with a lot more power than you guys are making with a hybrid. That's not my opinion, or some assumption. Many tuners have done so for a few years now. I am not some noob talking out his lol

To be honest, I took a long break from the Fiesta community. I don't know much about Randy or what he does (or doesn't do). I've only heard good things about him actually, HOWEVER, and this is just my honest opinion, I myself would not send out partial dyno graphs like that for public consumption.

Where do you get "drastically" from? He said it was falling off, so what's the point of revving more? Also what I meant earlier was that If the turbo can make more power at higher rpm, then it's going to need more fuel, which the hpfp is limited at. We both know 300 is the "magic" number, but the tuner may feel uncomfortable pushing the car to end up blowing it up just to make the extra few hp. That creates a bad rep really quick for them. Also Randy is cool as shit and you could simply email him or Dan at mountune or call with your questions and he will tell you why. He knows mich more than I could ever waste your time explaining. I just chimed in because you said you wanna avoid the tuner like the plague, but he's actually a good tuner and a good guy as well. He wouldn't do you or anybody wrong. Scouts honor!

 

[jeff]

This was a real dyno. The graph ended at 6200 which is before red line. Red line is set at 6600. You have no idea what happened after the graph ended so you are just making assumptions. I will leave my redline right where it's at because I trust my tuner and he said power was falling off. You may set your redline as high as you would like on your car. Thanks for your opinion. I'm not being a dick btw. ☺

Why would your tuner let off at 6,200 instead of running the engine into the rev-limiter? Your dyno graph just shows peak power and nothing else compared to stock.

Looking at *YOUR* graph, power is still climbing when it shuts off at 6,200 rpm.

I'm curious too as to why it cut off at 6200. Even if that's the spot for peak power, there's no reason not to run it to redline, especially considering the tuner established the redline for the car.

I can't speak for the MRX but having the X47 on my car I noticed both on my real dyno runs and all my many (50 of them) V dyno runs that power does peak right around 6100rpms. My tuner raised my redline to 7200 which is safe in his opinion (Tune+) but he told me plainly that that's not going to help max power. Again, looking at my charts, it's pretty clear that that is true. But that's the X47, I don't know about the MRX but I am curious.

In either case maybe there is more power above 6200, but even if not it's nice to have the redline higher if you're trying to get to 60 in 2nd gear, then it is possible. But revving to redline every time is counterproductive if you want to stay in the maximum powerband since it does not hold max power all the way to 7000. Again, that's the X47, I'm assuming the MRX is the same but I could be wrong.

 

[pelotonracer2]

Where do you get "drastically" from? He said it was falling off, so what's the point of revving more? Also what I meant earlier was that If the turbo can make more power at higher rpm, then it's going to need more fuel, which the hpfp is limited at. We both know 300 is the "magic" number, but the tuner may feel uncomfortable pushing the car to end up blowing it up just to make the extra few hp. That creates a bad rep really quick for them. Also Randy is cool as shit and you could simply email him or Dan at mountune or call with your questions and he will tell you why. He knows mich more than I could ever waste your time explaining. I just chimed in because you said you wanna avoid the tuner like the plague, but he's actually a good tuner and a good guy as well. He wouldn't do you or anybody wrong. Scouts honor!

I'm sorry but that still doesn't change the fact that the hp curve is still going upwards @ 6200 rpm according to molten16s graph and there is no way to tell what this particular cars powerband really looks like. lol. This is the FIRST dyno run I have ever seen that just cuts off at 6200 rpm for THIS application. "drastically" would be the only reason not to show the rest of the power curve. lol. Does it stay straight to red line or does it fall on it's face? No one knows because the information is missing.

I know that the magic pixy dust target of 300whp is close to the fuel limit with some hybrids, but I have also heard different things about the MRX hybrid that suggests it runs out of steam (kind of like the stock turbo) at well under what the stock fueling system can handle. I have no way of verifying that claim though since I don't have an MRX.

molten16s dyno run is about as useless as a pixel on a computer screen because there is still 300-400 revs of rpm left before hitting the limiter. Most experienced dyno operators don't let off the throttle at 6200 rpm and better yet they print a graph that goes to fuel cut. Even if this particular engine's powerband flattened or started declining, when compared to stock or a typical stage 3 setup, it would be interesting to see the power difference UNDER THE CURVE to support any argument pertaining to limiting redline/rev limit to any given rpm . As I stated before, 6600 rpm is VERY safe (like stock) and your tuner is leaving what I would consider a measureable amount of performance on the table for the end user. I have a 7000 rpm rev limiter and I initiate a shift at 6800 rpm. With that flat of a power curve, I don't see a benefit in short shifting at say 6200-6300 rpm if it is still making 80% or more power at redline.

If you look at ANY dyno graph of a STOCK turbo car and one from a hybrid or other big(ger)turbo, the BIGGEST difference you will see is that the stock turbo loses a ton of efficiency as rpm increases and boost must be tapered down. Sure it is fairly easy to get 27 psi "peak" @ 2300-2400 rpm, but the boost must be tapered down from there. This really is not the case with a good hybrid. Most tuners run around 24-25 psi all the way to rev-limit because the efficiency of the turbo is increased and heat generated is considerably less. That means a stock turbo car might only be making 90-100hp at the wheels at redline while I bet a hybrid turbo car will make almost twice that AT THE SAME RPM. And there we have it...

 

[Bretley]

I'm sorry but that still doesn't change the fact that the hp curve is still going upwards @ 6200 rpm according to molten16s graph and there is no way to tell what this particular cars powerband really looks like. lol. This is the FIRST dyno run I have ever seen that just cuts off at 6200 rpm for THIS application. "drastically" would be the only reason not to show the rest of the power curve. lol. Does it stay straight to red line or does it fall on it's face? No one knows because the information is missing.

I know that the magic pixy dust target of 300whp is close to the fuel limit with some hybrids, but I have also heard different things about the MRX hybrid that suggests it runs out of steam (kind of like the stock turbo) at well under what the stock fueling system can handle. I have no way of verifying that claim though since I don't have an MRX.

molten16s dyno run is about as useless as a pixel on a computer screen because there is still 300-400 revs of rpm left before hitting the limiter. Most experienced dyno operators don't let off the throttle at 6200 rpm and better yet they print a graph that goes to fuel cut. Even if this particular engine's powerband flattened or started declining, when compared to stock or a typical stage 3 setup, it would be interesting to see the power difference UNDER THE CURVE to support any argument pertaining to limiting redline/rev limit to any given rpm . As I stated before, 6600 rpm is VERY safe (like stock) and your tuner is leaving what I would consider a measureable amount of performance on the table for the end user. I have a 7000 rpm rev limiter and I initiate a shift at 6800 rpm. With that flat of a power curve, I don't see a benefit in short shifting at say 6200-6300 rpm if it is still making 80% or more power at redline.

If you look at ANY dyno graph of a STOCK turbo car and one from a hybrid or other big(ger)turbo, the BIGGEST difference you will see is that the stock turbo loses a ton of efficiency as rpm increases and boost must be tapered down. Sure it is fairly easy to get 27 psi "peak" @ 2300-2400 rpm, but the boost must be tapered down from there. This really is not the case with a good hybrid. Most tuners run around 24-25 psi all the way to rev-limit because the efficiency of the turbo is increased and heat generated is considerably less. That means a stock turbo car might only be making 90-100hp at the wheels at redline while I bet a hybrid turbo car will make almost twice that AT THE SAME RPM. And there we have it...

Lol a pixel on a screen, that's was friiging funny! I get where your coming from, you wanna see the whole graph and not before redline. I totally agree with you as I'm excited to see results to be aware of the gains I'll get when I upgrade to the billet wastegate this coming spring. I can tell you from my kit that it peaks torque at 4000-4100, and hp at 5800-6000 on the stock wastegate. Peaking at 27 and tapering down to 21ish. I need to correlate a time with the local dyno and Randy so he can finalize everything live and I'll give you a dyno chart but it with the stock wastegate. My rev limit is set at 6850, I'll give you all of it! Lol

 

[pelotonracer2]

Lol a pixel on a screen, that's was friiging funny! I get where your coming from, you wanna see the whole graph and not before redline. I totally agree with you as I'm excited to see results to be aware of the gains I'll get when I upgrade to the billet wastegate this coming spring. I can tell you from my kit that it peaks torque at 4000-4100, and hp at 5800-6000 on the stock wastegate. Peaking at 27 and tapering down to 21ish. I need to correlate a time with the local dyno and Randy so he can finalize everything live and I'll give you a dyno chart but it with the stock wastegate. My rev limit is set at 6850, I'll give you all of it! Lol

Heh. I was trying to be funny, not sarcastic.

That would be pretty cool. I do like looking at dyno graphs, especially when I compare the same car with different mods (and on the same dyno of course). Which billet aftermarket WGA are you going to use? Are you going to use the stock BPV with a DV+ or going aftermarket? Your target rev limit of 6850 will be fine.


I have an X47R install on Thursday but I won't have any dyno runs for a couple weeks. I'm going to use a Turbosmart WGA and a DV+. It will be sweet to compare the two different hybrids, plus tunes once we both get it sorted. I am not doing aux fuel as of yet. Good luck with yours.

 

[antarctica24]

The rev limit is set to 6850 on my mrx kit, wonder why yours is set lower to 6600? I don't even have the upgraded WG... It's probably pushing the fuel limits past that rpm with the upgraded WG. Yours is making about 35-40 more hp and tq than mine. (Using vdyno with all parameters inputted) so probably even more in real world settings.

Bretley, the rev limit is set based on what the datalogs are showing based on altitude. None of these cars are going to ever show the same results because there are way too many variables. Octanne, altitude, barometric pressure and then bolt ons like the fmic, intake and exhaust, and the do catted or not. Then their is the whole fuel problem. No body is hitting over 300 on stock fuel. No 47, 47r, mrx or any body else’s turbo. If they are they are lying. You have to use race gas to get over 300 and even then your almost limited to about 310-315. You need an aux fuel kit and at that point it almost seems like the money doesn’t justify the gains. This applies to Every single turbo on the market for the fiesta st.

This whole conversation just seems silly. This turbo on 93 oct will make almost 300 and 315ft tq at sea level. If you want more then get yourself a aux fuel
Kit, and a bigger turbo. It was rated at 275/275. It makes way more tha it was advertised to make. Can any of the other turbos make that claim?

These are the undisputed facts. Who cares if this turbo runs out of steam at 6899, 6500, or even 6000 rpm. Who is driving their car for more than a spit second at 6899 rpm? Are you running around town driving at 6899 rpm? The driviablity of this car is really between 3000-5500 with the mrx turbo. maybe a little higher but just having completed a drive from Washington State to Missouri 1900 miles at 100mph the car is hanging just below 4000rpm and driving a car at that rpm level for hours at a time is rough on a car, but as I have said I have a ford prototype so I’m not worried about it. So unless your driving at 150mph at 6899 rpm for more then 5 minutes this whole conversation is mute.

No body here cares that the mrx turbo doesn’t make 27lbs I’d boost sustained through 7500 rpm. Not one person.

You can go smaller turbo and lower the band, or you can go bigger turbo and raise the band. But curusing at 80 hovering around 2800-3000 it does not take much gas and this car is ballistic and is an unbelievable amount of fun to drive.