I posted this on tuners but no one is helping. Since it is GVR4 specific, I was wondering if I could get some thoughts here...
I have posted bits and pieces about this in other threads but it is now my primary problem. Please no comments about multiple threads on the same topic since this is a new primary issue.
I have set my MBC at 22 psi with my Big 16g. By 4500 rpm, boost drops to 20 psi. By redline, it is at 17 psi.
I have replaced the MBC just in case it is an issue and still have the same problem.
I have Boost Leak Tested the system with a 6 gallon compressor and have been able to take the pressure up to 30 psi. I do hear air from the valve cover oil cap when I remove it even when timing is set to 30 degrees ATDC. It is not as bad as others have described and I don't want to go broke spending too much money and time on valve stem seals if it not the cause of the boost fade. In fact, I have read that hearing some air from the valve cover opening during a BLT is normal. All BLT are performed cold.
Compression is 161-165 across the board.
I have replaced the throttle shaft seals and put RTV over the BISS Screw opening due to boost leaks. I put the one way check valve to the PCV as well.
My BLT situation is far better than it was before overall and I am not so sure I want to continue to blame boost leaks for this issue.
I have also gotten a Dodge Modded BOV (I really think it looks more like the Dejon but others say it is Dodge Modded).
All of this and I still have the above Boost Fade Problem. In fact, someone else had or has an identical issue:
Is Boost fade normal? - DSM Forums: Mitsubishi Eclipse, Plymouth Laser, and Eagle Talon Forum: DSMtalk.com
All of my mods are in the signature. (Note the 40mm Tial Wastegate). The spring is 16 psi. The wastegate is apparently 10 years old. I contacted Tial to find out more about it since the previous owner installed it. Maybe the spring is tired after that long? (They didn't seem too worried about it).
Could you all give me your thoughts?
Thanks!
Mods are:
Ported Big 16G Turbo, ETS FMIC & Piping, XBC MBC, Custom 2.5" tubular SS O2 housing with 40mm TiAL wastegate, turbo back Buschur 2.5" mandrel bent SS exhaust and CATCO cat, 1G DSM shifter with 2G DSM shift knob, Autometer Vacuum/Boost Gauge, Nordskog oil pressure gauge, custom turbo oil return line, FRAM airhog air filter, Mighty Max oil filter housing for relocated oil filter, M1 15w-50, HIR 9011 and 9012 bulbs, fog lamp delete, Warlboro 190 lph pump, Fuel Pump Rewire, FIC 650 injectors, Alarm with turbo timer and remote start built in, Innovate LC-1 Wideband O2 with guage, Triple gauge pod below radio, removed insulation under carpet, vented carbon fiber hood and carbon fiber hood pins. Socketed EPROM ECU with Ostrich and ROM emulator, Stutterbox and Check Engine shift light, using RT Tunerpro for tuning. Palm iiic w/mmcd hardwired into car (charges battery too), JDM GVR4 trans from Noyan, PTT twin disc clutch and flywheel with organic discs, SS Clutch line, Dejon Stop Leak Kit for BOV, Stock Head and Cams
I have posted bits and pieces about this in other threads but it is now my primary problem. Please no comments about multiple threads on the same topic since this is a new primary issue.
I have set my MBC at 22 psi with my Big 16g. By 4500 rpm, boost drops to 20 psi. By redline, it is at 17 psi.
I have replaced the MBC just in case it is an issue and still have the same problem.
I have Boost Leak Tested the system with a 6 gallon compressor and have been able to take the pressure up to 30 psi. I do hear air from the valve cover oil cap when I remove it even when timing is set to 30 degrees ATDC. It is not as bad as others have described and I don't want to go broke spending too much money and time on valve stem seals if it not the cause of the boost fade. In fact, I have read that hearing some air from the valve cover opening during a BLT is normal. All BLT are performed cold.
Compression is 161-165 across the board.
I have replaced the throttle shaft seals and put RTV over the BISS Screw opening due to boost leaks. I put the one way check valve to the PCV as well.
My BLT situation is far better than it was before overall and I am not so sure I want to continue to blame boost leaks for this issue.
I have also gotten a Dodge Modded BOV (I really think it looks more like the Dejon but others say it is Dodge Modded).
All of this and I still have the above Boost Fade Problem. In fact, someone else had or has an identical issue:
Is Boost fade normal? - DSM Forums: Mitsubishi Eclipse, Plymouth Laser, and Eagle Talon Forum: DSMtalk.com
All of my mods are in the signature. (Note the 40mm Tial Wastegate). The spring is 16 psi. The wastegate is apparently 10 years old. I contacted Tial to find out more about it since the previous owner installed it. Maybe the spring is tired after that long? (They didn't seem too worried about it).
Could you all give me your thoughts?
Thanks!
Mods are:
Ported Big 16G Turbo, ETS FMIC & Piping, XBC MBC, Custom 2.5" tubular SS O2 housing with 40mm TiAL wastegate, turbo back Buschur 2.5" mandrel bent SS exhaust and CATCO cat, 1G DSM shifter with 2G DSM shift knob, Autometer Vacuum/Boost Gauge, Nordskog oil pressure gauge, custom turbo oil return line, FRAM airhog air filter, Mighty Max oil filter housing for relocated oil filter, M1 15w-50, HIR 9011 and 9012 bulbs, fog lamp delete, Warlboro 190 lph pump, Fuel Pump Rewire, FIC 650 injectors, Alarm with turbo timer and remote start built in, Innovate LC-1 Wideband O2 with guage, Triple gauge pod below radio, removed insulation under carpet, vented carbon fiber hood and carbon fiber hood pins. Socketed EPROM ECU with Ostrich and ROM emulator, Stutterbox and Check Engine shift light, using RT Tunerpro for tuning. Palm iiic w/mmcd hardwired into car (charges battery too), JDM GVR4 trans from Noyan, PTT twin disc clutch and flywheel with organic discs, SS Clutch line, Dejon Stop Leak Kit for BOV, Stock Head and Cams
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