I'm not trying to start a long thread on something thats been covered but I'm trying to get a simple answer to a question ive struggled to find in the long discussions on this topic. If I'm not mistaken mazda recommends 5w-20 but yet very few use it due to it thinning out too much and creating low oil pressure and higher temps. Wouldn't those using 5w-20 solve this issue by installing the re-medy oil pressure kit or the racing oil pressure regulator to increase oil pressure or am I off here? Does anybody that has installed either of these have any feedback as well? I was trying to see what application this mod would be best for, my 8 is NA.

 

The rotary before the series I Renesis had higher oil pressure and the current Series II Renesis has higher oil pressure so I think it is obvious which is better. The weight of the oils I have used do not seem to affect pressure. I have the Mazmart mod and see the same oil pressures with 0W-40, as I have seen with 5W-20, 0W-30, and 5W-40.

 

The Remedy oil pressure mod only changes when the *bypass* opens, raising the maximum allowable pressure in the system from ~70 psi to ~120 psi. Until the bypass opens, the oil pump operates in a constant displacement mode (flow varies directly with rpm) which means the exact same volume of oil flows regardless of the viscosity (within reasonable limits). A more viscous oil is however "harder" to pump through the system, so the oil pressure will rise faster with rpm than with a thinner oil. There is no difference in the volume pumped until the bypass opens (~4500 rpm) at which point the thinner oil will be flowing more volume than thicker even though the pressure is the same (stock ~70 psi), because the bypass will open earlier with the thicker oil. Seeing higher pressure at a given (lowish) rpm with heavier oil does not mean it's "better", in fact, with the stock OP bypasses, it's a bad sign. The mod lets the oil system run in constant-displacement mode throughout the rpm range, making it safe to use heavier oil if one should decide to do so.

 

Yeah what he said.

 

lol

op look up and read a little about oil film strength. That is why people shouldnt use the 5/20W oil.
OD

 

oh i thought there was some debate whether to doing this mod

 

For the reason OD mentioned, I chose to go with Castrol 10w-30. IMHO, it's a very positive mod wrt *possibly* extending engine life. The only downside I see is perhaps slightly lowering the mpg's. For further thoughts on the subject, see: https://www.rx8club.com/series-i-tech-garage-22/my-sneaky-plan-extend-engine-life-series-i-190372/

 

so If im understanding correctly, it doesnt matter what oil you use to realize the benefits of modding for increased oil pressure?

 

People have quoted that tolerances in the rotary aren't any closer than they ever were, and they believe a heavier oil is called for. I run a heavier oil because of their advice.

I didn't do the Oil Pressure Mod only because it was more work than I was willing to take on at this point. Otherwise I think it is a good idea - i would do the Racing Beat one because the pressures aren't quite as high as the REmedy mod.

 

I was kind of leaning toward the racing beat mod myself, Its not supposed to be that much work to do, is it? I thought it looked pretty straight foward, maybe slightly messy

 

Getting the pan so there are no leaks was one of my concerns. Also, doing it on jack stands. These things don't bother real men, but I am still a wanna be mechanic.

 

One can drop the pan with the car on ramps. I had a hard time getting the pan loose from the sealant gooped everywhere (there is no gasket), but mine engine was practically new. The pan is steel but the other surface is aluminum which is quite soft, so be careful how you pry. Be aware there is ~ a quart of oil left in the bottom of the pan *after* draining from the plug, so don't dump it on yourself. It's not very close to the edge, but letting the pan tip a lot when bringing it down is guaranteed to make a first class mess. When gooping the sealing surface before reassembly, don't get goop into the bolt holes. They are blind holes in aluminum, so enough stuff in there might cause the "crankcase" to crack when the bolts are tightened. And def use a torque wrench - just estimating could get you stripped threads. There are pics etc in the early pages of this thread:
https://www.rx8club.com/series-i-tech-garage-22/mazmarts-oil-pressure-bypass-install-some-surprising-findings-189899/
Overall, not a difficult job if done with some care.