Mountune Fiesta MRX Turbo

[re-rx7]

Look at denver. Barometric pressure still at 29ish, in fact here is a link for you. your car is making 250ish on 93. which is about correct

http://www.localconditions.com/weather-clovis-new-mexico/88101/

 

[jeff]

I've read through most of this thread and will be interested to see more real dyno results.

Vdyno can be manipulated, I've learned that. Many of the X47 Vdynos I see have HP around 300 but they don't adjust pressure or temps. Were they to do that they'd be closer to 280 which is where mine ends up on every pull I do on 93 octane. Datalog while going down an interstate ramp, you'll show 300. But that's dishonest.

One thing I noticed about the MRX though, back on topic - if it truly is making 275 on a Mustang dyno then 300 is realistic. Reading through this thread I didn't see much talk about that. The original Mountune dyno runs were done on a Mustang which most of us know reads a good bit lower than a Dynojet. Props to Mountune for using the dyno and posting results knowing they could be higher on a different machine. But if it is making 275 on a Mustang it would no doubt make 300 on a Dynojet.

 

[re-rx7]

Proof is in the pudding. If you adjust the Baro on those pulls the car is making 250ish. Better yet, dont SAE correct it.

 

[antarctica24]

OK, thanks, just wanted an another opinion because kansei on here could not tolerate the sound pressure of this system without the resonator, at all, and reinstalled his cp-e resonator after trying it without.

Mitch @ CPE and I have had conversations and I have spoken with another guy at Garrett about the exhaust situation. The problem here is if your going to make 300 you need 3". This is a hard rule that has always appliedand is clearly documented on about 100,000 websites both technical and by experience. When using a turbo, it is all about unrestricted zero backpressure exhaust. Over 350 the rule says the bigger the better. While there are some here making close to 300 and 300 on the stock size exhaust you are leaving power on the table. With that said, the resonator does nothing for the loudness of the exhaust All it does is change the tone. I have much experience with the exhaust on this car. I have had 4 various types of exhaust systems both catted and catless. I have changed the resonator on the CPE to a longer smaller diameter and it did make a difference and it changed the tone, but nothing I have done under the car, ever changed the loudness of the exhaust. It only moved the tone in the frequency range. I am using a Audio Control RTA to measure the changes. If you want to control the loudness of the exhaust it has to be done at the tailpipe. The only options here are straight through mufflers, if you dont want to give up power.

Mitch has mentioned some options.

The goal of an exhaust for this car in a modified stated should be

The goal should be to remove the drone from 3K to 5K under moderate driving. under WOT who cares.
The goal should be to remove or greatly reduce the noise at startup, and low RPM and low MPH driving
If I am cruising at 60-80mph, Remember where i live, in Idaho (right down the road), it is 80MPH and the same heading towards Seattle in I-90. I am in Spokane WA. I should not hear the exhaust, You are close to that now at 60, but at 70-80 the exhaust note is too loud to have a normal conversation in the car.

Mitch responded with the following
So we have a few options:
-Adjustable helmholtz resonator. (see CP-E Focus ST Exhaust)
-Dual exit- The more I think about it, im not sure how well this will do at cutting sound by itself. Space is really tight with the spare tire well so adding a muffler or resonator might be a stretch
-Boost Actuated Valve- This can pair up with dual exit. Have the second exit have a boost actuated valve. Theoretically, the closed valve will act as a second helmholtz resonator to bounce back sound waves when not under boost.
-Second helmholtz resonator Cobb Style (Cobb 135i exhaust)- more space efficient.
-Adding a "race muffler" between the stealth pipe and the tips such as this one

At this point I am not willing to give up my straight through exhaust as I am not willing to sacrifice any power. So I will be examining these options and should I make a profound discovery i will share my findings.

For the haters, yeah I know, its a high hp 4 cylinder. I have no car, no muffler, its going to be loud. I get all that, however and but, it doesnt mean I cant try to find a solution to drop the volume some under specific conditions.

 

[kivnul]

I think part of the pressure problems is that people do not adjust for elevation. The posted pressure (regardless of where you are) is at SEA LEVEL. You have to correct that pressure to your actual elevation. So right now wunderground shows my pressure at 30.12 in. I am at 1800'. At a rough 1" = 1000', my actual air pressure is at 28.32 in.

(EDIT: wunderground is special in that it shows both actual and sea level pressures. It does not do a good job of labeling which it is showing at the time. The main page for a station is actual pressure. The almanac page shows sea level. Make certain that the station you are using states which type they show. Traditionally they show sea level so pilots don't smack into mountains because they set their altimeter wrong)

 

[antarctica24]

Why is everyone one of the high hp logs barometric pressures way off? Ive done the research on the days and the barometric pressure arent even close. With the correct Barometrics in place the dynos are all around 250ish......wtf

We are not using the weather channel or weather.com to obtain our readings. I am using the iphone as it has a barometer built in to give at location readings.
The rule generally is as altitude goes up barometric reading goes down. When i was at Lake Louise last week in BC, altitude was 6500 feet with a baro reading of 23psi. They were selling 94 oct gas, had I been able to get a tune, I would have been make 350hp.

With that said, Vdyno is not consistently reliable and when it is you know it because the HP and TQ numbers between smoothing 1, 2, and 3 are different by less than 1 percent. When they vary by 10 percent or more you had a bad run.

Randy says that the smoother the road the better the reading. If you look at your smoothing zero, the smoother that is, the smoother the road was you were running on. I have found this to be very accurate which makes a big difference in your numbers. The smoother the road,and the smoother smoothing zero, the higher and more accurate your numbers will be.

My buddy in Raleigh, NC just made a run on his MRX, and hit 314hp@6144 and 336tq@4115 with weight of 215 baro of 23.5 and temp of 70 at altitude of 313ft on 93oct. Vdyno is very sensitive to the barometric reading. You can ask the accessport to measure baro, and compare to what your phone tells you providing you have an iphone7. But I find that on the mornings I am datalogging the bara reading on my phone is within 1% of weather.com at the local weather station in the area.

All of my runs are on 92 Oct.

 

[antarctica24]

I dont believe that to be correct. The iphone7 is giving the actual pressure at the location of the phone as it has a sensor built in. The app also shows current elevation accurate to 50 feet.

 

[antarctica24]

Look at denver. Barometric pressure still at 29ish, in fact here is a link for you. your car is making 250ish on 93. which is about correct

http://www.localconditions.com/weather-clovis-new-mexico/88101/

Same website Spokane WA, current readings 30.8inHG, my iphone reads 28.068inHG my current elevation 1673.93.

The phone is accurate for the location where the phone is not the weather station location.

 

[re-rx7]

Post non sae corrected numbers. You dont believe the weather channel that uses local weather instruments and data?

 

[re-rx7]

Same website Spokane WA, current readings 30.8inHG, my iphone reads 28.068inHG my current elevation 1673.93.

The phone is accurate for the location where the phone is not the weather station location.

Horseshit. One post had a pressure of 25. 25 dude. Come on

 

[TyphoonFiST]

Horseshit. One post had a pressure of 25. 25 dude. Come on

Hmmm

Sent from my SAMSUNG-SM-G935A using Tapatalk

 

[re-rx7]

if at 4k ft elevation the temp was 45degrees in the depths of summer 25.84 would be your baro.

https://en.wikipedia.org/wiki/Atmospheric_pressure

 

[Bretley]

Damn, i just want 1 YouTube video of this turbo in action. Maybe even a real dyno sheet too (not mountunes), if all stars align! Please make it happen you awesome guys!

 

[antarctica24]

Horseshit. One post had a pressure of 25. 25 dude. Come on

First I speak for no one other than myself. I don't know what other people are doing but I can speak of the barometric sensor in the iPhone. It's the Bosch bmp 280.

A comparison was done at www.extremestorms.com/iPhone_6_barometer.htm

As you can see at that page the application corrects for altitude and shows baro pressure at sea level. Nothing to do but read it. It is very accurate. As for others using baro reading and where their getting their information I can't speak to that. As for using vdyno as a accurate measurement theirs your horseshit. Although as I have tested and said, I have absolutely no reason to lie and I won't. If my turbo doesn't make anything more than 265 then that's what it is. I have nothing to prove to anyone and in fact don't need to pump up the product. I think it's a good product and I am very happy with the results. If th wg offers an improvement I will add it. But I'm not some people who just keep swapping out turbos to get an extra 5 hp.

If you want a real reading of your power quit be cheap and go get on a dyno. That's what I will be doing before the end of the month.

Vdyno I think can be close if you recognize the following.
Road must be smooth the smoother the better and when I go to the dyno I will be datalogging and comparing my numbers to vdyno.
You have to correctly correct for cae and by correctly I mean honestly. I see nothing to be gained by falsifying results.
If your numbers between smoothing are writhing 1 percent you can take smoothing 2 to the bank
If your results are more than 1 percent between smoothing you had a bad run and would not rely on what vdyno is telling you.
You can tell how rough the road was by looking at smoothing zero. The smoother it is the smoother the road was.

I consider Randy's opinions and knowledge to be excellent regarding his product and his knowledge about vdyno.

For others reading this post if you are one of those people who like to modify their data to post better numbers you are just hurting yourself. Be honest about what you post. When you do your runs be consistent, collect all relevant data like gps location, altitude, baro from your iPhone, pick a nice flat surface, get the temp and humidity start your run at 2k run at 2k for 10 seconds, then put your foot to the floor and carry it until redline, then take your foot off the gas, let it rev down to about 5k then stop your logging.

Don't forget no ac and turnoff esc.

The more consistent your logging the more accurate your data will be.

With everyone doing their own version of logging it's hard to be able to verify the data. What I have listed above will give you accurate results every time.

 

[antarctica24]

I think part of the pressure problems is that people do not adjust for elevation. The posted pressure (regardless of where you are) is at SEA LEVEL. You have to correct that pressure to your actual elevation. So right now wunderground shows my pressure at 30.12 in. I am at 1800'. At a rough 1" = 1000', my actual air pressure is at 28.32 in.

(EDIT: wunderground is special in that it shows both actual and sea level pressures. It does not do a good job of labeling which it is showing at the time. The main page for a station is actual pressure. The almanac page shows sea level. Make certain that the station you are using states which type they show. Traditionally they show sea level so pilots don't smack into mountains because they set their altimeter wrong)

The iPhone app automatically corrects for this. It shows pressure at your location and at sea level

 

[re-rx7]

when you take these pressure readings are you using the inside car temp or outside?

 

[eglove]

When I purchased my MRX I was told the wastegate actuator wouldn't have to be adjusted as my batch was "corrected" compared to the first batch that was messed up. Well..guess I am "topped out" gotta take the turbo off to adjust the wastegate. Not really wanting to take it apart again. I wonder since I am at this point - I should just order that other wastegate and see if I can get better numbers out of it. I've been fairly busy with work and life stuff so my tuning process with Randy has been slower. (Purchased Turbo July 1st - installed July 22) Neither his fault or mine. Just kinda disappointed with my vdyno numbers. Another recommendation was to get a different intercooler as my CPE intercooler may be causing boost to drop? I dunno.. don't get me wrong car is a riot now. But seeing Brura's numbers and mine for similar elevation is disappointing

 

[antarctica24]

when you take these pressure readings are you using the inside car temp or outside?

Outside I do my runs and take my readings from outside the car before and after the run

 

[antarctica24]

Outside I do my runs and take my readings from outside the car before and after the run

Also I think the lowest I've ever seen was 27.5

You can't take wiki and use some formula for determining baro pressure. The meter doesn't lie. What wiki is referring to is under perfect conditions.

 

[antarctica24]

Also I think the lowest I've ever seen was 27.5

You can't take wiki and use some formula for determining baro pressure. The meter doesn't lie. What wiki is referring to is under perfect conditions.

I did see 24 at lake Louise in British Columbia two weekend ago at about 6000 feet