Garrett V-band TwinScroll GTX35r Topmount Experiment
Jul 28, 2013, 11:48 AM
#106
I ran the gas tank down to ~1/4 full and drove around trying to see if the heat would build in the fuel system. After driving and 30 minutes of idle in ~85F weather I could see the ethanol content sensor start to fluctuate. The sensor is after the FPR so when flow is reduced through the sensor its readings start to jump around. At this point I put my hand on the fuel filter that is now located in the rear of the car and it is very warm.
I suspect the issue is the fuel pump putting heat into the gas and slowly raising the temperature. I have both the primary and secondary pumps hot wired through relays, which is something I changed when installing the Squash double pumper. With the stock fuel pump wiring and Haltech I had the pump running low voltage and kicking to high voltage at 5psi.
The primary Walbro 400 will go back on the stock wiring so it runs low voltage when cruising.
<5psi - low voltage (stock wiring)
>5psi - high voltage (stock wiring)
>12psi - secondary pump (hot wired through relay)
I suspect the issue is the fuel pump putting heat into the gas and slowly raising the temperature. I have both the primary and secondary pumps hot wired through relays, which is something I changed when installing the Squash double pumper. With the stock fuel pump wiring and Haltech I had the pump running low voltage and kicking to high voltage at 5psi.
The primary Walbro 400 will go back on the stock wiring so it runs low voltage when cruising.
<5psi - low voltage (stock wiring)
>5psi - high voltage (stock wiring)
>12psi - secondary pump (hot wired through relay)
Jul 28, 2013, 02:15 PM
#108
I don't hear the pumps, but I also have 3.5" exhaust from turbo to back.
The hose in the box is aluminum tubing, which will run from the exhaust to the closed catch can. I was worried about the heat so I wanted something metallic. All other hose will be standard black rubber heater hose with -10AN pushlok fittings.
The hose in the box is aluminum tubing, which will run from the exhaust to the closed catch can. I was worried about the heat so I wanted something metallic. All other hose will be standard black rubber heater hose with -10AN pushlok fittings.
Jul 28, 2013, 06:52 PM
#110
I suppose I can route the fairclough -10an fitting from the back of the valve cover straight to the exhaust without a can. Since it is pulling crankcase pressure from the baffled area within the valve cover it may not be an issue. I want to avoid clouds of blue smoke during WOT.
Aug 27, 2013, 11:21 AM
#112
UPDATE:
I have been very busy at work and home so not much time to tinker. I am just about finished with the new catch can setup and will be using both the turbo inlet and exhaust scavenge to eliminate block pressure. I will datalog results so I should be able to quantify the performance of both methods individually as well as together. All fittings are -10.
I have been very busy at work and home so not much time to tinker. I am just about finished with the new catch can setup and will be using both the turbo inlet and exhaust scavenge to eliminate block pressure. I will datalog results so I should be able to quantify the performance of both methods individually as well as together. All fittings are -10.
Any updates?
Oct 3, 2013, 06:21 PM
#118
Nov 23, 2013, 02:45 PM
#120
UPDATE
I was driving my car on the highway today and took my exit and came to a stop at the stop sign. I immediately noticed the car would barely run and managed to limp home. I knew it was cylinder #3 because EGT's were low.
I swapped plugs...no change, swapped coils...no change, compression test...0psi
I pulled the valve cover and found the GSC valve spring snapped. I don't know if the valve is damaged. I have been running these springs for almost two years with the last 6 month being with the R2's.
I was driving my car on the highway today and took my exit and came to a stop at the stop sign. I immediately noticed the car would barely run and managed to limp home. I knew it was cylinder #3 because EGT's were low.
I swapped plugs...no change, swapped coils...no change, compression test...0psi
I pulled the valve cover and found the GSC valve spring snapped. I don't know if the valve is damaged. I have been running these springs for almost two years with the last 6 month being with the R2's.