Mountune Fiesta MRX Turbo

[re-rx7]

You have it nearly right but boost pressure forces on the actuator diaphragm to move the rod and open the wastegate flap. The solenoid is normally open meaning the boost signal flows from the compressor outlet to the actuator and is powered up to close so the boost signal is bleed off allowing the boost pressure to rise higher the actuator spring pressure. The normally open design is a fall safe meaning if the solenoid fails or we have a broken wire the actuator stills works.

View attachment 15547

if thats the case...Im bleeding boost instead of keeping it? THE pressure keeps the door shut=100%WGDC no pressure = spring pressure. at 100wgdc arent you using the boost pressure to keep the door shut?

 

[Sekred]

Ok, I see where your going. Yes you are bleeding boost or pressure off the actuator diaphragm which is acting against the actuator spring pressure which holds the door shut. So if it takes 7 psi of force to over come the spring pressure and we want 14 psi of boost pressure then the ECU opens the solenoid, pressure is bleed off, boost rises till around 14psi, solenoid closes, boost drops, solenoid opens, boost rises and the cycle repeats very quickly (duty cycles). At 100% duty cycle the solenoid is powered continuously and all boost pressure from the compressor is bleed off, nothing is flowing to the actuator. As you said if you are really at 100% duty cycle then it sounds like the wastegate is getting forced open by the exhaust pressure in the turbine/exhaust manifold or the turbo is out of flow.

 

[re-rx7]

sounds like the wastegate is getting forced open by the exhaust pressure in the turbine/exhaust manifold or the turbo is out of flow.

Thats the 2k dollar question lol

 

[Hijinx]

This can boiled down really simply. 100% WGDC is all the boost. 0% is spring only. If you're at 100% and boost is falling, you're either: A) out of turbo or; B) boost leak (or pushing the WG open). Maybe [MENTION=3707]Turboman17[/MENTION] can answer this: if it's a weak WG, won't it flutter?

 

[antarctica24]

The turbo on my car is off right now. At 100% WGDC there just isnt anything else to keep the door shut. Thats with the WGDC wide open. Yes, our cars use a 3port solenoid system. It uses the "boost" pressure to put pressure on the diaphram from the top to keep it shut.

This is what I am reading as well. I hold 97% WGDC until I hit max boost, then my WGDC goes into the 80% then 70%.

So does that mean there is not enough spring pressure to keep the WG shut? Based on what I am looking at in my datalogs, it appears the Wastegate does something when boost hits 21psi. Opening or closing? As boost ramps up from there, the WGDC number then begins to drop from the 80's to the 70s and as RPM gets past 5K and boost starts to come back down, WGDC starts to climb back into the 90's and back to 97.

So the question is, if the wastegate spring is not holding the boost (Anyone and dont be cryptic) use plane english for us dumb folks. Then if we change the wastegate to something with a stiffer spring, do we have the fuel and octane to support the boost over a longer period, or if boost rises, do we have the fuel or octane to support more? All we have here is 92 oct. All of the runs I have posted have been on 92 oct. I have access to VP Racing gas which we will be tuning soon. But I would not want to run that all the time for obvious reasons. I had two really good runs this morning which I hopefully will be allowed to post

 

[re-rx7]

I think this boils down to wastegate. Mine was not pretensioned. I may try that first before installing the 14psi gate. Antartica are you on a aftermarket exhaust?

 

[kivnul]

Mountuneusa is running a laborday sale. Works out to about 8% off. code LD17

$1,563.08 w/out tuning. I am soooo tempted.

 

[Bretley]

Mountuneusa is running a laborday sale. Works out to about 8% off. code LD17

$1,563.08 w/out tuning. I am soooo tempted.

Me too! Just under 2k for the kit, pro tune, and bov. My wife is gonna be so pissed! Lol

 

[KnockOff]

Hopefully they have a tax season sale like this.

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[kivnul]

I haven't done all the homework I should, but:
a)what is needed to run a recirc bypass valve? (not wanting vent to atmosphere)
b)how well will it work with a CPE intake? (assuming have to find an adapter of sorts)

 

[antarctica24]

I think this boils down to wastegate. Mine was not pretensioned. I may try that first before installing the 14psi gate. Antartica are you on a aftermarket exhaust?

Yes I'm running catless 3" to the nexus cpe 3" so basically open pipe from turbo to exit

 

[M-Sport fan]

Yes I'm running catless 3" to the nexus cpe 3" so basically open pipe from turbo to exit

With or without the (front) resonator?

If without; is it ear-splitting loud?

 

[letitreign]

With or without the (front) resonator?

If without; is it ear-splitting loud?

Last time I spoke with Ron from whoosh, he had not sold a single cpe system without the resonator because of how redicilously loud it was. Even with the resonator at WOT you snapping necks lol

 

[antarctica24]

With or without the (front) resonator?

If without; is it ear-splitting loud?

I took out the cpe resonator and replaced with a different one but it is still loud

 

[M-Sport fan]

I took out the cpe resonator and replaced with a different one but it is still loud

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.

 

[M-Sport fan]

Last time I spoke with Ron from whoosh, he had not sold a single cpe system without the resonator because of how redicilously loud it was. Even with the resonator at WOT you snapping necks lol

I have this system as well, with the cp-e front resonator, and YES, you most definitely HEAR it at WOT, but any other time the tone/sound level is just about perfect.

But then mine would be much quieter than most since I am still on the factory downpipe, vs. many others (either with or without hybrid/BT setups) with their 3", no catcon, aftermarket downpipes.

 

[re-rx7]

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

 

[STAZ15]

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

Mine hovers around 29.84 according to the weather channel.


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[re-rx7]

Mine hovers around 29.84 according to the weather channel.


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sounds about right, easy to look up. just google

 

[Brura22]

Im at almost 5000 ft[emoji23]


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