K&N Air filter for SuperCharger?

[-XXX-]

Have you ever spent a week at Moab? Have you ever been in the middle of a large group that is traversing a long stretch of unpaved road?


One day of that would expose you to a year's worth of hiway operation.

I totally understand, I was remarking about why would one change it just to go off road- why not leave it on while on road too? ITS NOT A RACE CAR!! the "Small" of proclaimed horse power would not bew worth me stopping to change a dumb ass filter.


with that said (jamisobe) your K&N DOES let more dust in (why else would you only change it off road?!)..... I never said it would blow up or make your engines fall apart but you can not deny the abraision will not accelerate when using a K&N, why would you use a K&N anyway ? ITS A LANDCRUISER NOT A TOP FUEL CAR whatever gain in performance you would get would not be worth the hassle of changing to the original OEM to go four wheeling every time you went off road.

 

[jamisobe]

I totally understand, I was remarking about why would one change it just to go off road- why not leave it on while on road too? ITS NOT A RACE CAR!! the "Small" of proclaimed horse power would not bew worth me stopping to change a dumb ass filter.


with that said (jamisobe) your K&N DOES let more dust in (why else would you only change it off road?!)..... I never said it would blow up or make your engines fall apart but you can not deny the abraision will not accelerate when using a K&N, why would you use a K&N anyway ? ITS A LANDCRUISER NOT A TOP FUEL CAR whatever gain in performance you would get would not be worth the hassle of changing to the original OEM to go four wheeling every time you went off road.

Easy enough for you then. It's a free country. If I were you I wouldn't make any performance modifications that would benefit you on the street. However, my 80 is dual use and I hope quicker than yours as well as most of the GMs, Fords, and Heeps running around. You might not care if it is, but I do.

 

[cruiserdan]

I totally understand, I was remarking about why would one change it just to go off road- why not leave it on while on road too? ITS NOT A RACE CAR!! the "Small" of proclaimed horse power would not bew worth me stopping to change a dumb ass filter.

Um,

I don't stop to change the "dumb ass" filter......


I run a stocker the whole time.

 

[-XXX-]

Um,

I don't stop to change the "dumb ass" filter......


I run a stocker the whole time.

I know YOU dont do that DAN, I seen you had thrown out your K&N (you made that clear a few times LOL) I was refering to those who made the comment about the "changing" of the filters when going off road.

I would like to take apart my stock filter on my 80 and measure the SQ inches/centimeters of filtering surface and compare to that of a K&N. as well as make some type of air flow measuring device to compare a new filter with a K&N- on top of doing a particulate test to see what size particles a OEM allows through VS a K&N.

Then take the samples put them under magnification and see the difference, anyone? or should I try this myself?!

 

[jamisobe]

I know YOU dont do that DAN, I seen you had thrown out your K&N (you made that clear a few times LOL) I was refering to those who made the comment about the "changing" of the filters when going off road.

I would like to take apart my stock filter on my 80 and measure the SQ inches/centimeters of filtering surface and compare to that of a K&N. as well as make some type of air flow measuring device to compare a new filter with a K&N- on top of doing a particulate test to see what size particles a OEM allows through VS a K&N.

Then take the samples put them under magnification and see the difference, anyone? or should I try this myself?!

You could do that. But, I think everybody here already agrees that the K&N will allow more finer particles through than OEM. That's the whole idea behind an OEM filter being better for the trails hot shot.

 

[SUMOTOY]

Um,

I don't stop to change the "dumb ass" filter......


I run a stocker the whole time.

Me too, there is no need to run a filter with more flow, the stocker does darn good. RT pic shows what I suspected, a standard application that is smaller than the stock filter. I wouldn't google a darn thing. Get out a tape measure and a calculator. RT point is well taken, you start doing the math on those filters, the K&N *has* to flow more just to equal the stocker.

Or, call K&N and get the airflow number off that filter. IME, K&N airflow numbers are really not that good, certainly nowhere near what you'd expect vs paper.

I read the mods on the truck that runs the K&N and I chuckle a bit. Ditch the heavy tires, run stock size, run premium gas, ditch the bumper, don't add the winch or the kaymar. Any/all of these mods so offsets the K&N gain (cough).

I use K&N on my motorcycle, because I can't make an airbox big enough to put in a paper filter (1400cc big block FJ). I think they are a PITA, they clog often, they are loud, and I'd trade them in a minute for a paper filter if I could.

On the 80, it's a no brainer, that filter is a monster in terms of surface area vs displacement.

I know a lot of folks that *want* to run them. I say knock yourself out. Better than what Mr. T delivered? I don't think the math or any dyno run would support that. All google quoted testimonials aside.

ST

 

[jamisobe]

I read the mods on the truck that runs the K&N and I chuckle a bit. Ditch the heavy tires, run stock size, run premium gas, ditch the bumper, don't add the winch or the kaymar. Any/all of these mods so offsets the K&N gain (cough).

Not sure why you have to be so nasty. Did I say something to personally offend you or what you do?

Anyway, here's the deal. I want to have a capable full sized truck that isn't a snail around town/and has umph on the trail. Full capabilities off-road are important to me without going hardcore (I want it to be dual purpose-the only reason I have been running the 33 M/Ts is because M/T technology has jumped forward to actually have very good street manners and initially I had no lift. Otherwise, I would be running A/Ts). Are my tires heavy? Yeah, but not much heavier then A/Ts and I need off-road tires for what I enjoy. I smashed my bumper so I decided a heavy duty bumper with tire carrier for departure is important-I need towing capability-I haven't seen an alloy bumper available. My front bullbar will only weigh 75lbs compared to your arb and be just as strong. I will use synthetic rope on my winch instead of cable. You may be well over 5000lbs but I'm not I don't plan on it. It's the wheeler in me that's want to be able to drive where the big boys drive. I want ground clearance, throttle response, I want to be faster than you and most of the other modded or stock SUVs/Pick ups running around town. That's the gear head in me. I'm not as far as I would like to be, but I'm working on that in my own time.

It's give and take. Depending on your needs and purposes you do things to accompish your goals. Fine, It's more important to you to spend your money on off-road capability and you'll sacrifice speed to get there quicker. Your perogative.

But get off my back! Just because you haven't convinced me that your opinion on K&N airfilters is the gospel doesn't warrant vitriolic rudeness. I disagree with you until further notice. Accept it and your blood pressure will be much lower.

 

[HIPPYHUNTER]

Ahhh.....The ole K&N Filter topic....it's the same argument/discussion on every forum that has petrol burning engines. Toyota folks are sure more ...eloquent....than the quad crowd I am ore used too.
For me....fourwheeler has K&N+ a prefilter, F-150 K&N, Cobra K&N, scooter stock,Land Cruiser stock.
All """filters""" filter better dirty ...dont they??? FILTER NOT FLOW.

 

[cary]

Not sure why you have to be so nasty. Did I say something to personally offend you or what you do?


But get off my back! Just because you haven't convinced me that your opinion on K&N airfilters is the gospel doesn't warrant vitriolic rudeness. I disagree with you until further notice. Accept it and your blood pressure will be much lower.

I'm sorry but your perception was completely off base. I have re-read sumotoy's post and I don't see any nastyness. He is pointing out the same things that I have, mainly that you are only seeing what you want to see and not the entire picture. Dropping 50 pounds in the weight of the truck would be more of a performance increase than you would ever see from a filter change, and helps handling and braking. Sumotoy thinks like a race car builder, there are two ways to make a car go faster, more power or less weight. Less weight puts less stress on all components so you start there. BTW, he runs a TJM, not an ARB which is much lighter.

 

[jamisobe]

Quote:
Originally Posted by SUMOTOY
I read the mods on the truck that runs the K&N and I chuckle a bit. Ditch the heavy tires, run stock size, run premium gas, ditch the bumper, don't add the winch or the kaymar. Any/all of these mods so offsets the K&N gain (cough).

I'm sorry but your perception was completely off base. I have re-read sumotoy's post and I don't see any nastyness. He is pointing out the same things that I have, mainly that you are only seeing what you want to see and not the entire picture. Dropping 50 pounds in the weight of the truck would be more of a performance increase than you would ever see from a filter change, and helps handling and braking. Sumotoy thinks like a race car builder, there are two ways to make a car go faster, more power or less weight. Less weight puts less stress on all components so you start there. BTW, he runs a TJM, not an ARB which is much lighter.

If what I wanted was to go as fast as poosible I would have bought a Vette and started modding the V8. Flat out speed on the street isn't my goal and I guess it seems to me that should be fairly obvious. I want full off-road ability while maintainin the best streetability possible. I am tweeking for performance without sacrificing off-road capability. It can be done.

I think it is disrespectful to imply that I am foolish for trying to take incremental steps in achieving my goal. You might disagree with the effectiveness of one of those steps and say so. But, insisting that you are absolutely right and I am absolutely foolish is wrong. That is the difference between someone who respectfully disagrees and someone who is a POO POOER.

A poo pooer has a hang up about being right so much so that he is insulted by differing OPINIONS. Its not about fact, for them its more about having the "right" unassailable opinion.

My tires are heavier than I like (but they are the best I can find that meet my needs) and because of their diameters I find myself running gears that are taller than my wallet at the gas pump likes, but give me a break. Don't call me stupid. It is my personal preference to be dual use with as much street performance as possible and Sumotoy's attitude goes far beyond me using the K&N. He brought the rest of my truck into it. The only peice that was up for debate was the K&N. Evidently, he doesn't know me, my goals, or my truck other than a FEW of my favoite mods in the signature line.

We can agree to disagree without being so stubborn that we resort to calling someone a fool (wrongly in my opinion) over opinion.

 

[cary]

I think it is disrespectful to imply that I am foolish for trying to take incremental steps in achieving my goal. You might disagree with the effectiveness of one of those steps and say so. But, insisting that you are absolutely right and I am absolutely foolish is wrong. That is the difference between someone who respectfully disagrees and someone who is a POO POOER.

A poo pooer has a hang up about being right so much so that he is insulted by differing OPINIONS. Its not about fact, for them its more about having the "right" unassailable opinion.

My tires are heavier than I like (but they are the best I can find that meet my needs) and because of their diameters I find myself running gears that are taller than my wallet at the gas pump likes, but give me a break. Don't call me stupid. It is my personal preference to be dual use with as much street performance as possible and Sumotoy's attitude goes far beyond me using the K&N. He brought the rest of my truck into it. The only peice that was up for debate was the K&N. Evidently, he doesn't know me, my goals, or my truck other than a FEW of my favoite mods in the signature line.

We can agree to disagree without being so stubborn that we resort to calling someone a fool (wrongly in my opinion) over opinion.

Wait, let me get this straight, before you asserted it was a fact that the K&N increases performance, now it is an OPINION. Before you kept talking about how a different intake with a K&N filter increased performance, which we told you was incorrect because in order to determine the performance difference from a K&N it had to be changed ceteris paribus. Now you are claiming the entire discusion was ONLY about the K&N!!!

As far as Sumotoy bringing the rest of your truck into it, as I previously explained, he pointed out if you were worried about very minor increases in performance, look other places for much more of a change.

Nobody here called you stupid, but you have managed to do a wonderful job of making the point yourself.

 

[kennyv0826]

Comon guys, gimmie a break, no one listens to these kinds of arguements when they turn rude. Just state your opinion and leave it at that. I don't agree with some of the things being said but it's not worth getting upset about.

If someone has some scientific proof that shows several different vehicles that have had negative effects from running a K&N (such as more engine wear or ruined sensors) then post it and we can make up our own minds. I've had good luck with all the K&N's I've run so until I have a bad experience with one I will probably continue to run them.

 

[jamisobe]

Wait, let me get this straight, before you asserted it was a fact that the K&N increases performance, now it is an OPINION. Before you kept talking about how a different intake with a K&N filter increased performance, which we told you was incorrect because in order to determine the performance difference from a K&N it had to be changed ceteris paribus. Now you are claiming the entire discusion was ONLY about the K&N!!!

As far as Sumotoy bringing the rest of your truck into it, as I previously explained, he pointed out if you were worried about very minor increases in performance, look other places for much more of a change.

Nobody here called you stupid, but you have managed to do a wonderful job of making the point yourself.

I never said it was fact that K&Ns always improve performance. Only that it is fact that sometimes they do. No need to go twisting words around to make yourself feel better about being completely wrong.

I will look to make mods wherever possible to increase performance (regardless of which of my multiple goals it meets) and i am open to constructive tips, but please check the insults along with unsupported conjecture and insistence at the door. If you can post some significant supportive information ( Inever doubted that it may exist) then post it. I only ask that we all use a polite tone rather than one of condescension.

I read the mods on the truck that runs the K&N and I chuckle a bit. Ditch the heavy tires, run stock size, run premium gas, ditch the bumper, don't add the winch or the kaymar. Any/all of these mods so offsets the K&N gain (cough).

That was impolite and out of context. My goal isn't speed at all costs. It is the best performance possible on the street without giving up significant off-road capability. Therefore, if a K&N can help then I will use it. Just because you say it won't doesn't mean I should believe you. But, if you use facts to convince me maybe I will. Fair enough?

 

[SUMOTOY]

That was impolite and out of context. My goal isn't speed at all costs. It is the best performance possible on the street without giving up significant off-road capability. Therefore, if a K&N can help then I will use it. Just because you say it won't doesn't mean I should believe you. But, if you use facts to convince me maybe I will. Fair enough?

Use the K&N, please stop short of saying it gives you any performance gain on an 80, it hasn't shown to do that. I brought your other mods into the picture, because you offset any percieved gain with weight, winch cable choice aside. Try the tire test, I've done it dozens of times. Put stock size and lighter weight michelins on, then put on the tires you chose for offroad. It's not just the weight, it's the reciprocating mass of big tires.

It's my business to understand gains. I build performance turbo motors for a living. I have very few street or track cars, that will benefit from the 'nth' power that possibly comes from the K&N. And in fact, my own dyno tests show that the bigger the filter, the less the chance of gain from K&N. And several problems can come up using them.

For the 80 application specifically, the K&N application is smaller than the stock app, which puts it at a disadvantage. It's also pretty obvious to a lot of us running boosted 80's, that the K&N is hardly necessary to gain power. If the majority of your driving is towards offroad, you want to take the K&N out anyhow.

Since I have an empty TJM and stock weight and size tires, I suspect that even removing my supercharger wouldn't give you any advantage in the 80 performance department. Do you run premium gas always? Do you use a vaccuum guage to measure filter service interval?

My *point* is, you can certainly use it, many do. Jumping on any claim that it's better than the stocker in terms of flow or performance, might require more than your testimonial. Get a gtech and or an oil analysis. I'm not trying to insult you, only point out that the reality of K&N is more marketing than performance in an application with a caparatively large paper filter.

I've run them, tested them, cleaned them, removed them, and even challenged the technical department on the low flow applications for specific motors. I understand the theory, I just don't buy the practical application or marketing.

ST

 

[jamisobe]

Use the K&N, please stop short of saying it gives you any performance gain on an 80, it hasn't shown to do that. I brought your other mods into the picture, because you offset any percieved gain with weight, winch cable choice aside. Try the tire test, I've done it dozens of times. Put stock size and lighter weight michelins on, then put on the tires you chose for offroad. It's not just the weight, it's the reciprocating mass of big tires.

Tire and wheel weight is a primary concern for me. However, very good off-road capability isn't something I want to sacrifice. So I need to find the best compromise for me. That means that I am stuck with larger tires and since I want M/Ts that perform well on the street I will be forced to go with Koyo which is a heavier 35" M/T. To compensate I will swap my 4.88s out for 5.29s. Its possible I may eventually buy a 2nd set for the road but $ is still going to new mods first.

It's my business to understand gains. I build performance turbo motors for a living. I have very few street or track cars, that will benefit from the 'nth' power that possibly comes from the K&N. And in fact, my own dyno tests show that the bigger the filter, the less the chance of gain from K&N. And several problems can come up using them.

Potential problems aside of which I am well aware. This isn't a race car. It is a modded land cruiser with which I want to maximize both street and off-road performance. I have to make some compromises and flex creativity in different areas. My exhaust is heavily modded and flows great. Therefore, from research I have done (not just what I have been told) there may be some gains to be had when exhaust flow is significantly increased or induction is forced. I am interested in scientific testing but not mere poo pooing. I would expect poo pooing from a backyard mechanic, not a pro. A pro would say I don't think so becuase of such and such, but I don't have the data.

For the 80 application specifically, the K&N application is smaller than the stock app, which puts it at a disadvantage. It's also pretty obvious to a lot of us running boosted 80's, that the K&N is hardly necessary to gain power. If the majority of your driving is towards offroad, you want to take the K&N out anyhow.

This is where we need more data rather than heresay. There are lots of ways to gain power and most of them are synergystic rather than one or the other (I like the idea of running a TRD supercharger with my current exhaust-I will save $ and be able to do the work myself). The majority of my driving is around town and on the freeway. 15% ugly off road, but this is my toy and currently my DD 85% of the time.

Since I have an empty TJM and stock weight and size tires, I suspect that even removing my supercharger wouldn't give you any advantage in the 80 performance department. Do you run premium gas always? Do you use a vaccuum guage to measure filter service interval?

I run premium gas, 4.88 gears (w/33s however), synthetic oil & grease only throughout, headers, 1 dynacat, 3" exhaust, magnecor wires with platinum 4 plugs, and a K&N. Stock bumper currently until I replace it with a 75lb ECB.

Brakes are Brembo slotted and crossdrilled with hawk ceramic pads(leaps and bounds better than stock). Lift is done properly and the truck handles better than stock aside from a slight compromise in the tire dept.

Obviously, a blown 80 may have a leg up on me but I now walk away from vehicles from which I couldn't when I first bought my 80 5 years ago even with stock 31s or whatever they were.

Never heard of anyone using a vacuum guage to determine filter change intervals. Would be interested in understanding potential gains from this practice. Gotta link?

My *point* is, you can certainly use it, many do. Jumping on any claim that it's better than the stocker in terms of flow or performance, might require more than your testimonial. Get a gtech and or an oil analysis. I'm not trying to insult you, only point out that the reality of K&N is more marketing than performance in an application with a caparatively large paper filter.

I never did say I was positive that there would be a gain. Afterall, how could I since I haven't seen the tests. I did say that as a result of this exchange that I could see how an OEM could possibly perfrom as well or even better. I am still not convinced that the OEM would outperform or that there is a huge risk from dirt with my particular application. Although, I think it would be a good idea to use an OEM on trail rides.

I've run them, tested them, cleaned them, removed them, and even challenged the technical department on the low flow applications for specific motors. I understand the theory, I just don't buy the practical application or marketing.

ST

Fair enough. I still believe that there may be better flow with the K&N despite surface area differences. I also believe now that for non-race off-road use that the K&N isn't the best choice. That doesn't change my mind about the potential advantages offered for street use. But, I have been known to change my mind based on solid research. We'll see what the future holds...

 

[SUMOTOY]

Potential problems aside of which I am well aware. This isn't a race car. It is a modded land cruiser with which I want to maximize both street and off-road performance. I have to make some compromises and flex creativity in different areas. My exhaust is heavily modded and flows great. Therefore, from research I have done (not just what I have been told) there may be some gains to be had when exhaust flow is significantly increased or induction is forced. I am interested in scientific testing but not mere poo pooing. I would expect poo pooing from a backyard mechanic, not a pro. A pro would say I don't think so becuase of such and such, but I don't have the data.

I expect those that test K&N marketing vs actual tested application performance might have a good opinion on them. You have put them in with percieved gains. I put them in and test gains, I don't see them objectively or subjectively. I am only interested in tradeoffs, performance and failure. I find nothing in the design of the 80 filter vs the K&N application that would make me think to use K&N. Do you know the flow on the K&N?

I run premium gas, 4.88 gears (w/33s however), synthetic oil & grease only throughout, headers, 1 dynacat, 3" exhaust, magnecor wires with platinum 4 plugs, and a K&N. Stock bumper currently until I replace it with a 75lb ECB.

Ditch the platinums, or get a good one like the FD5POR (expect to pay for a real platinum application, these list at 27USD ea). Those '4's will tear up the ceramic coating on the electrode, btst. The stock plug application is better IMO. Magnecors I'd expect with a K&N (no offense), I usually see one with the other. I haven't measured a gain in using a good quality stock wire (and Mr. T makes one of the best). In fact, unless a wire fails, I haven't seen wires do a darn thing. Regarding the cat, remember it's surface area at a given pressure. If you used a single 3in cat, you have probably reduced the flow of the exhaust there. Ck the math out, I don't think you've gained anything doing that. 2 3in cats, maybe.

Brakes are Brembo slotted and crossdrilled with hawk ceramic pads(leaps and bounds better than stock).

See my brake comments under separate thread. Watch for cracking around the holes of the drilled, unless they are chamfered, the first time you heat them up, they will crack. Ceramic pads are not recommended for extreme duty use, don't use them if towing or offroad, it's specifically not recommended by Bosch and Raysbestos. Again, the best mod for the brakes would be to get cool air to them. Crossdrilled on a rotor that gets hot, is a recipe for failure, unless you've ducted cool air to them. Then IME, the cool air negates the need for the crossdrilling.

Never heard of anyone using a vacuum guage to determine filter change intervals. Would be interested in understanding potential gains from this practice. Gotta link?

K&N specifically states that in their tech section on their website. Not sure how you'd know proper service interval otherwise
http://www.knfilters.com/filter_facts.htm#SINTERVAL

Fair enough. I still believe that there may be better flow with the K&N despite surface area differences. I also believe now that for non-race off-road use that the K&N isn't the best choice. That doesn't change my mind about the potential advantages offered for street use. But, I have been known to change my mind based on solid research. We'll see what the future holds...

Borrow a gtech meter. It's very accurate to a given application, given change. Put the stock filter in, then put the K&N in. It's pretty easy. Then try taking the filter out all together. I think you will find the results surprising. You don't need a dyno for this.

ST

 

[jamisobe]

I expect those that test K&N marketing vs actual tested application performance might have a good opinion on them. You have put them in with percieved gains. I put them in and test gains, I don't see them objectively or subjectively. I am only interested in tradeoffs, performance and failure. I find nothing in the design of the 80 filter vs the K&N application that would make me think to use K&N. Do you know the flow on the K&N?

I intend to test at the track.

Ditch the platinums, or get a good one like the FD5POR (expect to pay for a real platinum application, these list at 27USD ea). Those '4's will tear up the ceramic coating on the electrode, btst. The stock plug application is better IMO. Magnecors I'd expect with a K&N (no offense), I usually see one with the other. I haven't measured a gain in using a good quality stock wire (and Mr. T makes one of the best). In fact, unless a wire fails, I haven't seen wires do a darn thing. Regarding the cat, remember it's surface area at a given pressure. If you used a single 3in cat, you have probably reduced the flow of the exhaust there. Ck the math out, I don't think you've gained anything doing that. 2 3in cats, maybe.

I have heard nothing negative re Bosch Plat IVs. Everything I have read has been positive. I have been running them for 60k miles and have had no problems. The advantage with the Magnecors is also longevity rather than raw performance gains.

I could see 2 3" inch cats if you plumbed them side by side (not sure how that would be accomplished) possibly increasing flow but I can't see it if they are consecutive. That isn't logical. You are increasing the amount of media through which the exhaust must flow. That would be like saying that putting two mufflers in consecutively will increase flow or eliminating your cats altogether would decrease flow. The more tricks you make your exhaust do the more restriction you create.

See my brake comments under separate thread. Watch for cracking around the holes of the drilled, unless they are chamfered, the first time you heat them up, they will crack. Ceramic pads are not recommended for extreme duty use, don't use them if towing or offroad, it's specifically not recommended by Bosch and Raysbestos. Again, the best mod for the brakes would be to get cool air to them. Crossdrilled on a rotor that gets hot, is a recipe for failure, unless you've ducted cool air to them. Then IME, the cool air negates the need for the crossdrilling.

Chammfered holes. The pads are actually ferro-carbon heavy duty. I was running through oem brakepads every 15-20k miles. I have had these suckers on there for about 40k with lots to go.

K&N specifically states that in their tech section on their website. Not sure how you'd know proper service interval otherwise
http://www.knfilters.com/filter_facts.htm#SINTERVAL

Sometimes I just like to wing it.

Borrow a gtech meter. It's very accurate to a given application, given change. Put the stock filter in, then put the K&N in. It's pretty easy. Then try taking the filter out all together. I think you will find the results surprising. You don't need a dyno for this.

ST

I'm gonna take it to the track...

 

[SUMOTOY]

K&N and beyond....

I intend to test at the track.

The CFM flow number from K&N tech department on the E-2443 application filter (all 4.5L 80-100) is 874 CFM. Have you done the math on the stock 4447Liter motor CFM? As many have said, Mr. T so overbuilt that oem filter that K&N could go even smaller.

What are you testing at the track? Use the gtech, I've used one and gotten within a .1 on the quarter and just about dead nuts on the dyno. For a back to back, that's all you need.

I have heard nothing negative re Bosch Plat IVs. Everything I have read has been positive. I have been running them for 60k miles and have had no problems. The advantage with the Magnecors is also longevity rather than raw performance gains.

Plat IV's use a ceramic coated electrode, not a ceramic electrode (like the FD5POR for example). It also uses a little tip of Platinum vs almost .200in of it on the F5. What I find happens with the cheap ones, is that the ceramic coating cracks, then the spark travels up the side of the electrode, negating anything close to a better spark. Again, the stockers are fine, you won't blow out the spark using them, so no gain is had from a 2.99 plug. In fact, since bosch is the oe for the turbo audis, I go thru this all the time. I recommend either FD5POR or just use the triple coppers (xxxDTC), they are the same price as the PIV and are a much better plug design. Regarding wires, the stock wires last forever, I replaced mine as PM at 12 years, well, because. That indicates to me that the new stockers will last another forever.

I could see 2 3" inch cats if you plumbed them side by side (not sure how that would be accomplished) possibly increasing flow but I can't see it if they are consecutive. That isn't logical. You are increasing the amount of media through which the exhaust must flow. That would be like saying that putting two mufflers in consecutively will increase flow or eliminating your cats altogether would decrease flow

I speak to leaving a cat for each bank, not in series, yes in parallel. It's easy to put dual high flow cats on the 80, cuz it already had them from the factory. In terms of the honeycomb, it's really tough to claim that laiminar flow thru a grid less than half the size of 2 grids will yield better flow. Even if you account for velocity. Exhaust is all about pressure drop. I doubt a 3 in system with the stock cats would decrease flow, and can math out that a 3in honeycomb cat will cause a higher restriction than the stockers. I also suspect if you took a measure of pressure drop on a cat back 3in, the 3in muffler would yield the highest backpressure, not the stock cats. BTMT on a lot of cars in my shop.

The more tricks you make your exhaust do the more restriction you create.

Not necessarily, x pipes, crossover pipes, antireversion steps, catalysts, nozzle diverters, laminar flow converters, all are tricks that give performance and flow gains, and can add no additional restriction.

Chammfered holes. The pads are actually ferro-carbon heavy duty. I was running through oem brakepads every 15-20k miles. I have had these suckers on there for about 40k with lots to go.

Glad you think it's working for you. As a rule slotted rotors tend to eat pads quicker, because the edge of the slot will clip them. I suspect that the carbon pads did more than anything to the rotor. Cross drilled look cool, I suppose, but there is little to support cross drilling or slotting that will yield gains in the 80. Put SS lines on them, and get air to them, run the stock pads. What gets the 80 in trouble is heat, btdt at Steamboat. A cast iron caliper needs to dissipate heat, pads don't do that well. Carbon can take more before failure, but they tend to be less agressive on initial bite, then get more so as they heat up. The problem with them IME, is that you overheat them, they will eat rotors immediately. The Semimetallics will get soft, indicating you have some heat issues before they eat the rotors.

Again, I only look at what you've done vs what 'gains' are inherent to what you've done. It's your machine, I only encourage testing in some quantitative manner. In the case of the K&N, you don't even need to test, just calculate... You are wasting your money if the stock paper filter flows half the CFM.

ST

 

[60wag]

I still want to know why if the blower (turbo or SC) is dumping boost through the wastegate or bypass due to high intake manifold pressure, does the intake filter restriction matter much at all. Yea, the upstream pressure of the blower will be lower with a clogged up filter but so what if the blower can still deliver max flow to the engine?

 

[SUMOTOY]

I still want to know why if the blower (turbo or SC) is dumping boost through the wastegate or bypass due to high intake manifold pressure, does the intake filter restriction matter much at all. Yea, the upstream pressure of the blower will be lower with a clogged up filter but so what if the blower can still deliver max flow to the engine?

Whoa up, two different systems. A turbo wastegate regulates exhaust turbine speed based on manifold pressure. The bypass valve in the SC or turbo is activated by manifold Vacuum.

I know that the stock filter can flow the maximum airflow a low pressure ratio boosted motor can flow, even with a dirty filter. I don't ever see a 80 runninig 874cfm, unless Christo has some 25psi turbo coming out soon...

ST