I mounted the high pressure pump to rubber on both sides off the boot wall and it is heaps quieter now. Went driving, out to an industrial estate about 5 kms from home, give it a bootful through second to get some speed up and test the brakes a few times. They work good
These KU36 are really sticky, you have to be seriously on it to even look like locking up. Got a couple of chirps out of the right front, will leave the balance bar where it is for now. This thing stops on a dime. That's the good news.
I drove for about 15 minutes then headed home, but nearing home the pump started to sound funny and fuel pressure started to drop.....it went down to under 30 before I pulled over as it nearly died. The low pressure pump was cold. The high pressure pump was just slightly warm to touch. I waited 30 minutes, then it fired again with 54psi and I got half way home before it happened again - when I switched it off I could hear gurgling like the surge tank emptying or some sort of vacuum going on or something.
Fuelab have been helping me via email with the noise and they told me my HP inlet from surge tank to pump was too small (-6) so I upgraded that to -8 after having the pressure problem, but still the pressure drop after driving remains. When it happens I can hear the high pressure pump starting to cavitate like the surge tank is out of fuel. I can only reason that this is whats happening, the car will idle forever will no problem, but after driving a few mins it seems the surge tank is emptying.
I have the test data sheets on the pumps, the HP pump is 70gph at 55psi, the low pressure pump is 120gph and there is no regulator on the LP pump. Both pump are running low speed mode (these stats are for low speed mode).
The line from tank to low pressure pump is also -6, and it has a strain filter on it, next step is to upgrade that to -8 and maybe a -10 strain filter.
Fuelab also tell me the overflow line from surge tank to main tank is too small (-6) and could cause a vacuum lock. I can't upgrade this without major work as the fitting on the tank is welded -6.
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