Quote:
Originally Posted by Element Tuning
Getting into the FRS BRZ oil pump.
As I've mentioned previously the FA20 motor is fitted with a newly designed 12mm oil pump gear compared to the 10 and 11 mm US EJ oil pumps. A Japanese model was offered with a 12mm pump gear but the case design was the older 10mm unit compared to the newer 11 mm designs we use on our EJ race engines. The biggest difference on these FA motors is the integration of the oil pump into the main timing cover and the fact that the oiling doesn't have to flow through the crank/rods first before oiling the heads like the EJ. On this motor you can see the oil feeds go directly to each head at the same time it feeds the mains and rods.
Now take a look at the difference between the EJ oil pressure bypass valve and the FA bypass valve.
It's totally different as the FA20 uses the shorter piston, shorter springs, dual springs, and even the cap provides a different level of preload. Now the bypass valve only controls the relief pressure it does not control the volume the oil pump is capable of delivering. We'll be making some modifications to the FA20 pump to see if we can successfully raise the oil pressure to a level we know will keep the oil wedge stable so we don't get rod to bearing to crank contact. Hopefully the pump has enough flow volume to maintain the higher oil pressure!
Thanks,
Phil Grabow |
I'm very curious how you're going to raise the oil pressure. The castings look smooth so I don't see gaining any flow from porting. And as you said, the spring doesn't set the operating pressure. Is there any chance the FA20T uses a wider pump that can deliver more flow?
Either way, thanks for another excellent post. I look forward to the rest of your build.