juanjux

Hello there,

I would like to ask if there is any difference in MPG, power, reliability, cooling, etc with the aftermarket oil filters (Mazdaspeed, K&N, etc) compared with the stock Mazda or cheap ones.

Thanks!

Mazda-Rati

I haven't seen any difference in performance or MPG between the Mazda, Fram TG or Prolator PureONE I've used.

Jax_RX8

No oil filter will impact fuel mileage, but will affect filter quality and oil flow.

While many oil filters filter well, it is also very important to have great "flow" as this helps overall lubrication and cooling of the rotary. For this reason, I use K&N Performance Gold oil filters as they filter well (on par with most) but flow better than any other filter out there.

mysql101

i use PureONE filters. Cost me $6-7 each (I forget, since I buy them in bulk)

http://www.calsci.com/motorcycleinfo/Filters.html

mysql101

ok, here's the link for where I buy them:

http://www.amazon.com/gp/product/B00...081855-2474048

I buy them when amazon has them on sale. My last invoice shows $5.88 each.

juanjux

Jax_RX8, those K&N filters were exactly the ones that made me wonders if they are worth the price and ask here, what it's the model that fits the RX-8?

BlueRenesis82

hmmm, every BISOG review I have seen says that the K&N is garbage.

fullsmoke

Agreed. Currently I only use Mazda filters on the 8, but on my 7's I use PureONE filters (the blue one).

FS

BlueRenesis82

I rock the PureONE on my 8

fullsmoke

I didn't even know they made one for the 8, but I learn something new every day. I love that filter...

FS

mysql101

Yes, this is for the exact filter you can drop in your 8:

http://www.amazon.com/gp/product/B00...081855-2474048

I've been using it for about 15k miles now (5 oil changes), no issues, runs great.

It costs under $6 with free shipping usually... what's the OEM filter cost?

KRNrx8Driver

hmm...i really should look into those...the shop where i get it done uses like napa or something iono but they use castrol GTX oil so i go there...maybe if the napa ones arent that great i'll just buy one you guys are talking about and just have them install it...hmm....

fullsmoke

Yes, I saw your postings above this one Thanks!

OEM at my dealer are like $4.70-ish for four (buy four for the discount). That's IIRC... My 85 RX7 is pushing 185,000 miles and I've stuck with PureONE for as long as I can remember!

FS

Jax_RX8

The PureOne is a great filter from a single-pass filtration standpoint, but it is also one of the most restrictive filters from a flow perspective. This can cause oil starvation in a performance engine run hard - and if pressure gets to the point that the "by-pass" kicks in (under high loads) then you are getting no filtration at all when the engine it at it's highest load.

I agree K&N is not the best filterer, it is average, but it is the best at flow which is also very important. K&N's ALWAYS filter the oil and have no by-pass installed because they flow so well they are not required. So you are getting filtration even under high load/pressure situations.

In the end, it depends on your priority, and for me I think flow slightly more important than extreme filtering capability - especially the harder you run the car.

fullsmoke

IIRC... A spring-loaded "pressure relief valve" built into the oil pump (or near the pump) opens when pressure exceeds a certain limit (typically 50 to 60 psi) and either reroutes oil back into the pump's inlet or the oil pan. This prevents a dangerous buildup of pressure that could rupture the oil filter or blow out press-fit oil plugs.

At idle, most oil pumps do not produce enough flow to force open the relief valve. Oil pumps that are camshaft driven turn only at half engine speed so output isn't great at idle and low rpm. Even pumps that are crankshaft driven and turn at engine speed (or double engine speed in a few instances) don't pump enough oil to overcome the relief valve spring. The relief valve generally only comes into play at higher rpm when the pump's output pushes more oil into the system than it can handle. Then the relief valve opens to vent oil and limit maximum oil pressure until the engine returns to idle or a lower rpm.

If I'm right, I just don't think that our stock system would build up a pressure that great to bypass the filter, unless there's blockage...

FS

Jax_RX8

Even if the pop-off valve is never activated on a restrictive flow filter, a more restrictive filter will cause reduced oil flow all the time. This impacts total lubrication and cooling all the time.

It is just now being realized that oil flow is actually MORE important than viscosity in providing total lubrication of an engine. Reference below for some good reading

http://63.240.161.99/motoroil/index.html

I personally would rather have much more oil flow with a little less filtering than to have less oil flow with more filtering.

nycgps

iTrader: (1)

It is HP-1008.

I use K&N filters on my other cars but I do NOT recommend you to use it on the 8. THe filter location for our 8 is a bitch just like all 13Bs. Couple days ago I was doing my oil change but my oil filter wench cant take the K&N off because of that *bolt* on the top of the filter. I have to Bang it like crazy for an hour before I can finally take it off ..... and I dont have any other filter at the moment so I dump another K&N in(cuz this filter model works for both my car and my bro's car, got couple of them laying around all the time) ........ hand tighten it this time and hopefully it would be easier for me to get it off next time.

Filters wont add any power to your car, you just want some filter that can filter as much dirty stuff as possible and some filters that can withstand high load (high pressure), Cuz some filters out there (FRAM?) actually fell apart under high stress and u know if the stuff inside falls out and goes into your oil/engine its not going to be funny.

Jax_RX8

I think so (at least in the US)

Filter # is HP-1008

Jax_RX8

I use the "bolt" on the end to put on and remove - that is what it is there for. Use a 1" socket with a universal joint attached followed by an extension, easy as pie for me.

fullsmoke

Jax Rx8:
You are correct about less flow, however, I do not think this is a major issue as the oil path is from the pan, to the pump, to the engine components, then through the filter back to the pan. Again, this is IIRC. Thus, since the system is wet-sump, I believe it will be more important to maintain a full level in the oil pan than have concerns with flow through the filter (although, yes, flow might be slightly down). But, that's just my two cents.

FS

ZoomZoomH

iTrader: (1)

i actually developed a small leak around the filter neck and the filter when I was using the PureOne, so I switched back to OEM, and no leaks since.

YMMV of course.

Jax_RX8

I understand the filtration is after the oil has passed through the engine, but this does not change flow dynamics. The bypass that is there is set at a very high rate and rarely comes into play (it's more a safety device) so for all essential purposes, this is still a closed system.

With "closed" systems, the lowest flow rate point (or choke point) in the system dictates the total flow rate for the entire system - in most cases this is the filtration point and in this case the oil filter.

So if you can increase flow capacity in the lowest flow point area (the oil filter in our case), you can increase flow through the entire system (to whatever the new choke point is, which is still likely the oil filter) - thus the importance of the flow capabilities of the oil filters and why I think it is one of the most important attributes in an oil filter.


But, for someone who does not ever drive their car/engine hard, a filter with more emphasis on filtering over flow may be justified - depends on the vehicle and how it is driven.

fullsmoke

I knew I'd get this response I realize that the choke point would be the filter as all the oil must flow through it. Either way, back to the main topic, you should get a filter that suits your engine demands, lol.

FS

Jax_RX8

Agreed. Just good to have as much info as possible to make yours decisions. LOL.

icyur2

Either the Mazda or K&N..I like the flow concept..as for putting it on and off, I only use hand to tighten it..don't use wrench..is that bad? I have yet to see pools of oil on my garage floor..and have it on for nearly 3K..