Porting the stock wastegate

[ElBartoRex]

anyone tried this yet to get rid of the boost creep/fuel cut/boost cut issues?

I have a tbe and an intake and I creep on WOT.

If I do this i will definitely report the results and do a how to!

 

[Demi]

subbed

 

[ericrapp]

Fuel cut, yes . ecu does not like more boost. created by all the flow you are generating. You can clamp voltages. Many of the fellows seeking performance on the forum can advise you in regard to that method.

 

[ElBartoRex]

Fuel cut, yes . ecu does not like more boost. created by all the flow you are generating. You can clamp voltages. Many of the fellows seeking performance on the forum can advise you in regard to that method.

The boost is spiking because the wastegate isn't big enough to control boost, so it spikes and then the ECU cuts it.

porting the wastegate will solve the problem if you are creeping with stock boost levels. I am aware of what a map clamp is and how it works, but you don't need a map clamp or a BCD until you actually raise the boost above stock levels.

 

[ericrapp]

Corky Bell theory. Well put. Ecu intervention is the issues. Have you resolved fuel cut with all the flow you are now generating with your mods. Nice #s by the way.

 

[ElBartoRex]

Nice #s by the way.

they are ok-- I will get better numbers once I can get a decent intercooler on the thing-- that stock TMIC gets hot to the touch after 1 dyno run...

why anyone would pay $700 for slightly bigger TMIC is beyond me.

 

[ericrapp]

pity the fool

they are ok-- I will get better numbers once I can get a decent intercooler on the thing-- that stock TMIC gets hot to the touch after 1 dyno run...

why anyone would pay $700 for slightly bigger TMIC is beyond me.

I am that person. not that much but a good bit, wanted stealth. A priority at the time. My investment is flowing just fine. The stock is imo not up to job for anyone who does the spirited driving thing. Upgrade as you choose, I believe the discussion will favor the front mount on all accounts but if the top mount design and flow numbers are appropriate for your application all is well. If you run one of the performance exhaust manifolds you might have to design some heat shield between the two and create some air movement or simply go front mount. Ps How about mine, IC is alot bigger!

 

[ElBartoRex]

I am that person. not that much but a good bit, wanted stealth. A priority at the time. My investment is flowing just fine. The stock is imo not up to job for anyone who does the spirited driving thing. Upgrade as you choose, I believe the discussion will favor the front mount on all accounts but if the top mount design and flow numbers are appropriate for your application all is well. If you run one of the performance exhaust manifolds you might have to design some heat shield between the two and create some air movement or simply go front mount. Ps How about mine, IC is alot bigger!

all good points. The MS3 almost looks like it was designed to make room for a FMIC though

 

[mrlilguy157]

resolved fuel cut? there is no hack or clamp that can prevent fuel cut, other than upping the rail pressure by getting a new CDFP.

As far as boost cut and fuel cut though, the first precautions that should be made would be that a map clamp or boost cut defender module should be used, and then doing the CPE Intake Air Temperature potentiometer fix. If you're still getting fuel cut/boost cut, then buy a CDFP, or cut to the chase and use a dashhawk or any datalogging device and log fuel pressure in 5th and 6th gears WOT, if it dips below 1500psi, you're doomed for a new fuel pump, which you'll absolutely love.

Mazda built the car to sustain AT LEAST 1540psi in the rail at wide open throttle.

 

[ElBartoRex]

resolved fuel cut? there is no hack or clamp that can prevent fuel cut, other than upping the rail pressure by getting a new CDFP.

As far as boost cut and fuel cut though, the first precautions that should be made would be that a map clamp or boost cut defender module should be used, and then doing the CPE Intake Air Temperature potentiometer fix. If you're still getting fuel cut/boost cut, then buy a CDFP, or cut to the chase and use a dashhawk or any datalogging device and log fuel pressure in 5th and 6th gears WOT, if it dips below 1500psi, you're doomed for a new fuel pump, which you'll absolutely love.

Mazda built the car to sustain AT LEAST 1540psi in the rail at wide open throttle.

can you or someone explain what causes fuel cut and how to tell the difference between fuel cut and boost cut? I always thought that they were different terms for the same issue.

 

[mrlilguy157]

can you or someone explain what causes fuel cut and how to tell the difference between fuel cut and boost cut? I always thought that they were different terms for the same issue.

Boost cut/Fuel cut feel the same, its both the throttle shutting to prevent from going lean.

Boost cut happens when you're over 18psi and don't have the MAP sensor tricked.

Fuel cut happens when rail pressure gets below 1500psi during WOT. This happens because the injectors are injecting so much fuel that the CDFP (cam driven fuel pump) cannot pressurize enough fuel and get it into the rail faster than the injectors are spraying.

There is also a boost/fuel cut issue with the intake air temperature sensor. When its cold outside (no set temperature at this point), the ECU will snap the throttle closed.

 

[ElBartoRex]

Boost cut/Fuel cut feel the same, its both the throttle shutting to prevent from going lean.

Boost cut happens when you're over 18psi and don't have the MAP sensor tricked.

Fuel cut happens when rail pressure gets below 1500psi during WOT. This happens because the injectors are injecting so much fuel that the CDFP (cam driven fuel pump) cannot pressurize enough fuel and get it into the rail faster than the injectors are spraying.

There is also a boost/fuel cut issue with the intake air temperature sensor. When its cold outside (no set temperature at this point), the ECU will snap the throttle closed.

so with a dashhawk I can see if its fuel or boost being cut.

 

[ericrapp]

There is a significant drop in fuel pressure on the stock System. Proven. which appears to freak the ecu out. Might be the the reason for fuel cut. The pump does not just stop flow. I did not see the afr to go lean. My biggest worry. More fuel is true enough with the build. But the ecu is doing the math on Mazda's settings.

 

[ericrapp]

At what percentage of injector duty cycle are your cars running at 6000rpm wot 4th gear Mrlilguy157. Just trying to do some math over here. And I believe you were able to maintain a pretty stable pressure. Could you tell me how many volts you are sending to control injectors. Thanks that would be a big help!