Posted: Jul 15 2006 at 5:24pm | IP Logged

actually almost all synthetics will theoretically free up horsepower, and improve mpg, one of the biggest reason people go to them as well as longer service periods. the reason being is they are enginerred to maintain their chemical and physical properties at the operating temperatures found in vehicles, you will see this in the numbers provided in product data sheets specifically the VI (vis index), noack volatility tests and sulfated ash %'s

i have been doing a lot of research, and while everyone touts amsoil, royal purple as being the best of the best...look at who they all point to as who they ourperform by name...usually i see mobil 1 as the big dog they call off the porch, there is probably a good reason for that. Mobil 1 has very good stats as far as the PDS, a high Vis. index which is a number that describes the ability to maintain the properties while at operating temperature...usually the higher the better as far as Vis index because it means as the oil heats up it does not change too much, because most oils will become thicker as it heats up, this is not a good thing at the extreme. also from what i've read they do not use any added polymers to their 5W-30 and i would presume the 10W-30.

Almost all synthetics have extreme temp ranges for flash and pour points and that is normal as they are engineered to tolerate the extremes.

sulfated ash numbers are lower on synths than a lot of mineral oils because they are also engineered to have lower ash, this is because if there is burn off at high temps, the ash is what becomes deposits (i.e. carbon deposits) in your engine.

i would argue that most of the synthetics out there today are pretty suitable for most people's applications and will protect your engine just fine, the one thing you have to be careful and mindful of is that on extended service, yes...synths will allow you to go longer between servicing, but the thing about synths that's i've heard is that when they do go...they go fast.

one thing that was mentioned is that quality of oil/air filters is something that is often overlooked, as if your high perf air filter will let more air in too...but what else is it letting in....a home grown study of diff types of air filters that i read showed that using a manometer and diff air filters each funning 500 miles, that paper filters filtered the best and their pressure drop (or decrease in air flow) was very minimal compared to the K&N which out of the tested fitlers was shown to have the highest flow rate, but also seemed to let the most crap in, and eventually some of that stuff will make it into your engine oil.

to that note..i'm probably goign to be bouncing my K&N filter from my truck pretty soon as i've read that the AEM dryflow was independently tested by a widely respected research company in texas...southwest research institute and found that it's flow rate was effected minimally cumulatively and was very effective filtration element and also no oil involved

also another route to go if you like the oiled fitlers is that the fram airhog for turbo/supercharged apps has 8 layers of filter element compared to the 4 of the normal air hog, and i believe K&N uses 5 layers. just some thoughts

Posted: Jul 16 2006 at 3:17am | IP Logged

[QUOTE=vq40de]well first of all you have an a cast iron block and aluminum heads the vq40de is all aluminum and it states in the manual for this motor 5w30 if 5w30 is not available you may use 10w30 but change to 5w30 as soon as possible and no one knows this motor like the people who designed this motor and as far as k&n you are screwing that motor up you better check into true flow.[/QUOTE

First of all, i think you need to re-read my post..i never claimed that either amsoil or royal purple are the best of the best, i said that they are touted to be the best of the best, and while those who swear by them like to pay the money for them...i will have to agree with kcidmil that the cost/benefit for them isn't justified for motor oil. I stated that if you look at who, specifically amsoil ads on the internet seem to call off the porch to challenge it's almost always mobil 1, and again...probably a pretty good reason for that, it's a highly respected product and treats your engine, whatever it may be nicely as far as i've read.

second, i'm not driving a fronty with the 4.0L V6, i have a 2001 with the VG33E, and as far as 5W-30, that's what's suggested for my truck...and well MOST OF THE vehicles coming off production today, it's the most suggested weight of oil from manufacturers today, with 10W-30 also stated as acceptable by most manufacturers as well, there is a reason they give you that little temperature chart for ambient temp in your owners manual, so you can select which oil best fits your needs, hell in my manual it even says 10W-40 is acceptable..but i wouldn't choose to put that in my truck.

for my air filter..i'm tempted to go back to paper filter like i said or the AEM dryflow filter after what i have read from this study

http://www.bobistheoilguy.com/airfilter/airtest1.htm, follow the links down at the bottom of the initial page to read the actual test and see picture of results

and then the following from SWRI and their test done on the AEM

new vs used

http://trucks.aempower.com/dryflow/SWRIresults_9inchdryflow_ newandcleaned.pdf

coarse dust test http://trucks.aempower.com/dryflow/SWRIresults_9inchdryflow_ coarsedust.pdf

severe abuse test

http://trucks.aempower.com/dryflow/SWRIresults_dryflow_sever eabusetest.pdf

results from SWRI on a few competitors' filters (sans a foam filter competitor)

http://trucks.aempower.com/dryflow/SWRIresults_injen5inch-kn 9inch-airaid9inch.pdf

now you'll note that after looking at the test results in pressure drop, that the filters from the first link avg'd about a difference in pressure of about 2, and the numbers i see for initial pressure drop for the dryflow is 1.31 or something around there for the new filter then 1.58 after "severe abuse" well if you compare that to the bob's test conceding that w/o any filter the pressure drop was about 5.1 inches of water, then add the 1.58 to the 5.1 and you end up with 6.68 inches of water, now granted this is pretty liberal extrapolating of data, but just suppose you go there with that...and then look at the number for the amsoil 2 stage foam filter, it's test results were for the foam and the amsoil foam was avg 6.5 inches of water drop and that was the best flowing foam filter, and second best flowing filter i believe in that test result, so that would put the AEM dryflow just slightly behind that in flow quality after having the crap beat out of it really, and if you took the new flow rates of 1.31 you'd end up with a total of 6.41 inches of water which would flow better than any of the foam filters in that test.

the biggest surprise to me out of all of this was that all of those filters had very very close flow rates for the stock filters in the www.bobistheoilguy.com test and the paper filter seemed to have the best filtration from the empirical data given in the results, i.e. the visual test,

one question i do have is whether or not it was a test of the CAI brute force intake with the dryflow filter or just the filter itself..i believe it was the filter itself from my reading. as this is just food for thought and something i found interesting and thought i'd share it with y'all, probably some of y'all have read it

Posted: Jul 16 2006 at 11:26am | IP Logged

Very interesting read.  Make up a new post in the modification section, sticky topic (Basics of Adding HP) 

That is the hard part, choosing your own downfall with the airfilter.  I noticed a huge difference between the stock Toyota filter, and K&N.  The gas mileage proves that.  But my friend's Camry had the MAF problem.  Luckily I caught it, and cleaned it for him before he took it to the dealer.  Had no problems after that. 

AEM's Dry Flow has caught my attention.  I'm thnking of using that on my Maxima.  So far I haven't had any problems with my oil soaked Ractiv filter.