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The Mazda parts used in this conversion include everything you need. As far as the sandwhich plate, the only concern would be how low the filter would sit after the install. I believe i was running a V6 Mustang filter which was a bit on the long side for a while, but there were shorter options that i can't remember off the top of my head that i'd recommend if you are adding a 1" plate into the mix.
Thanks for this article - it helped me out a lot when I followed it and completed my swap months ago.
Question for you though; recently my car has been making a faint grinding noise upon acceleration from a standstill. Verified it has nothing to do with the transmission or clutch or suspension. With the car in neutral, if you hold the rpms at 2000-3000 you can hear a faint inconsistent grinding noise.
After further testing, it appears the sound is coming from the top part of the motor. Long story short, I've been getting a lot of heat from the Mazda techs at the dealership because they noticed I have a mazda3 filter on there as opposed to the paper cartridge based one that car was designed for. They all say the same thing - and actually the mazda part guy who sold me the part warned me and said "you will mess with your oil pressure by switching this part and I really don't want to sell you the part." Long story short, maybe they were right - who knows...
At complete idle the car sounds normal at 750 or so rpm (or whatever it idles at - it idles at the same range.) When I'm driving, it sounds normal as well. I was running the prosport sandwhich plate for a while with an active oil pressure gauge. According to the gauge, the car was running at 70 or so llbs at 60-70MPH and at idle it was idling at 40 llbs with a semi-warm engine and 30 llbs with a totally-warm engine!
30 is rather low! I have a mazda mechanic friend who checked the repair book and it says it should be between 50 and 90 llbs. The only engine mod to this car is the oil filter swap from paper to spin on filter. If the car is still idling at 30 llbs of oil pressure, maybe the low oil pressure broke something inside the engine which is causing it to grind like that from initial acceleration?
Nonetheless, have you or has anyone else ever checked the numbers to see what the idling oil pressure is of the stock paper cartridge filter compared to the mazda3 spin on oil filter? If they both run the same oil pressure then I can stop worrying about this.
Everyone keeps saying the oil filter swap is to blame for this engine problem. I want to run it by you guys to see if anyone has experienced an oil pressure issue attributed to this swap/modification.
Please help if you can. I really hope nothing serious has happened to the engine.