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TR2/3/3A TR3A After Market Air Filters?

Jesus, thanks for that information. I had no research to indicate it but I've felt that the paper air filter would do a better job than the old original steel mesh filters. Not to start the ZDDP discussion again, ;) but I called Shell Oil Tech support a couple of months ago and the person guaranteed me that the Shell Rotella-T 15/40awg contains 1200 ppm of ZDDP, which is the level I understand is needed by flat tappet engines. As a result, I now use the Shell Rotella-T 15/40.
Regards,
Bob
 
Jesus - thanks for the report. The original wire mesh filters were typical of the 40s.

Silicon (sand) is pretty common, but what is "induced dust across the air filters"? My brain isn't picturing that.

Thanks.
Tom
 
...what is "induced dust across the air filters"?...

Maybe 'sucked in' didn't sound very scientific?

Considering how dusty everything gets where I live I can well imagine that lots of silica would be consumed by the engine with some ending up in the oil.
 
Considering how dusty everything gets where I live I can well imagine that lots of silica would be consumed by the engine with some ending up in the oil.
Of course, it would be good to know how much of that came through the intake air filters (and past the rings), versus how much came in through the crankcase vent.

I have no doubt that the original air filters just barely deserve the name, but it would still be interesting to know how much gets in through the vent.

If you are interested enough, here is a clever method (I thought) of DIY filter testing:
https://www.bobistheoilguy.com/airfilter/airtest3.htm

Although it would greatly reduce performance during the test, I think you could do the same test by inserting the sheet of secondary filter between the main filter and the carb.
 
Randall - thanks for that link. Wish he had been able to test an oiled wire mesh filter too.

What are your conclusions on his results? Paper is best? or ...?
 
Jesus - thanks for the report. The original wire mesh filters were typical of the 40s.

Silicon (sand) is pretty common, but what is "induced dust across the air filters"? My brain isn't picturing that.

Thanks.
Tom

Tom, sorry if I am not able to use correctly some English terms.

As Geo states, I meant really “sucked-up”, but used incorrectly the verb I thought related to the term “induction process” (maybe still more correct “intake process”).

As far as the “dust” that causes silicon in the oil, it is usually sand or soil dust, predominant in dry regions.

Further, I assume that the “dust” went through the filters because the intake system is airtight. But as Randall points out, the crankcase vent can be of course another route.

Jesus
 
Yikes! I forgot you are in Spain. Your English is excellent, and much better than my Spanish. By "induction" you might prefer "intake".

Ay de mi! Se me olvido' que este en Espanya! Su ingles esta excelente, y tan mejor que mi castellano. Por ,induction' sera' mejor decir "intake".

Qbsp.
Tom
 
Randall - thanks for that link. Wish he had been able to test an oiled wire mesh filter too.

What are your conclusions on his results? Paper is best? or ...?
That test, like every other one I've seen, seems to show that paper filters perform best overall. They do offer more restriction than the "high performance" filters (eg K&N), but also do a much better job of removing dirt from the air. So the "gravel catchers" are probably better for racing (although a good velocity stack would be better yet), but paper is better for overall engine life.

Here's another, more scientific study that puts numbers on the performance. The charts are a big exaggerated (the bottom of the chart is not zero so the differences are exaggerated) but the numbers are interesting. Well, to me anyway :smile:
https://www.billswebspace.com/AirFilterTest.htm
 
That second test, and the accompanying text at the bottom of the page, is really quite eye opening to me.

Excerpt:

* * * * *

Now that I am not doing the tests and my objectivity is not necessary, let me explain my motivation. The reason I started this crusade was that I was seeing people spend a lot of money on aftermarket filters based on the word of a salesperson or based on the misleading, incomplete or outright deceiving information printed on boxes and in sales literature. Gentlemen and Ladies, Marketing and the lure of profit is VERY POWERFUL! It is amazing how many people believe that better airflow = more power! Unless you have modifications out the wazoo, a more porous filter will just dirty your oil! Some will say " I have used aftermarket brand X for XXX # years with no problems. The PROBLEM is you spent a chunk of ching on a product that not only DID NOT increase your horsepower, but also let in a lot of dirt while doing it! Now how much is a lot? ANY MORE THAN NECESSARY is TOO MUCH!

* * * * *
(I also remember the "cold air intake" kits.)

 
It is amazing how many people believe that better airflow = more power! Unless you have modifications out the wazoo, a more porous filter will just dirty your oil!
Well, that part I don't necessarily agree with, at least not for a gasoline engine. (The article was written about diesel engine filters, and diesels are a different case.) Even dead stock, restricting the intake is going to reduce maximum power. The question is though, by how much? Ignoring the fact that a TR3/4 motor is never going to pull 350 cfm without a blower, the author documented initial filter drop as being about 1.75" H2O higher with the most restrictive filter (compared to the least restrictive).

Since one atmosphere of pressure (the amount of pressure normally pushing air into the engine) is about 400" H2O, we can estimate the loss in power at 1.75/400 or about 0.4%. Or, if we assume your motor is actually making around 100 bhp, the AC filter would cost less than 1/2 horsepower. On the race track, where races are sometimes won by .01 seconds, that might be enough to make a difference. But you'll never notice it on the street!

PS, Diesels are a different case because they don't have to balance fuel flow with air flow. Most stock diesel engines are power limited by the injector pump (fuel flow) rather than air flow. Of course, the first thing you do when hot-rodding a diesel is turn up the fuel!
 
I cut these filter covers from a SHOP VAC foam sleeve 90585. During a show just slide them off. EASY!






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Bo, That is one spotless engine. It's so clean it hurts my eyes.

Is is that a correct battery ? Never seen one.
 
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