Hey jdemaris

I just saw the thread below where you were looking for an air filter housing/assembly. Before you go getting the filter from Surplus center you need to figure the CFM requirement of your engine. Better yet give Donaldson a call and see what they recommend. I see where one post did a CFM calculation for your engine but, unless I missed something, it was for a normally aspirated engine. Since a turboed engine uses more air than a naturally aspirated one the CFM calculations have a multiplier to cmpensate for that fact. I can't recall exactly what it is at the moment but it does make a difference. One thing I do know for certain is that if you restrict the inlet flow the life expectancy of the turbo is greatly diminished. What happens is that it is trying so hard to suck the air through the filter that it adds an excessive thrust load to the bearings. As an example hold your hand over the end of a vacuum hose. The smaller you make the hole the harder it pulls against your hand and the same goes for the turbo, the harder it sucks the more pull/thrust is created by the impeller wheelcreating excess heat as well as premature wear on the bearings.

Here is a link to Donaldsons web site where you can look for a housing using alot of different variables from the rated CFM to the inlet and outlet size. Suprisingly enough you can get housings with the same diameter openings but with widely different ratings, I guess all due to the design of the housing and the way it makes the air flow through it. If you find what you want there you should be able to order one through a distributor. I've bought several from them over the years for various pieces of equipment and the cost isn't as bad as you'd think.
Donaldson

Remember how tough you could make them old beaters sound by turning the air filter cover upside down??????

I'm not turbo engineer, nor am I a math wiz. I was kind of hoping just to use an air cleaner off an application that I know works (like a factory setup from a GM 6.5 turbo).

I'm not building a street racer. This is a small 4WD motorhome and I'm rarely going to run the engine above it's peak torque curve -which with an added turbo, is around 2000 RPM. At that engine speed, it should have 375 lb. ft. of torque and 136 horse. That would require around 200 CFM. But, some needs to be added for dirt in filter, and those rare times when I stomp on the pedal to climb a steep hill, pass, etc.

A stock (no turbo) 6.2 run at 2000 RPM needs around 130 CFM. 6.2 (379 cubes) has a volumetric efficiency of 60%.

General rule of thumb that takes all into consideration (turbo or no turbo) is 1.5 times horsepower equals CFM need.

A stock (non turbo) 6.2 barely climbs above 120 horsepower - which comes to 180 CFM.

A 6.2 with a turbo, when driven in a "useful" RPM range, can make a max of 200 horse, thus needing around 300 CFM of air flow.

I've got another variable which is turning into an additional research project. The turbocharer I have does not match anything that Banks ever used. It fits the Banks exhaust manifold fine (no adapter), but I'm not sure if it's original or not.

The Banks system does NOT use a wastegate. Max boost is determined by the size of the turbo. I'd like to make sure this turbo isn't too big. It's possible that it's original and Banks just did not retain early records?

Turbo I have now is a Rajay Rotomaster- model 3AA1EE10B1. Housing is stamped with a A/R of .8.
It's supposed to be equivalent to a TO4 turbo. Rajay catalog says it was designed for 350 gas engines - so it might be sized right.
Only thing close that I find in Banks literature for the 6.2 is a Rajay T40B turbo with a 1.0 A/R ratio.

I'm not really sure yet what that means. Is the T40B bigger then the turbo I have now? I'm just trying to find out if I have to add a wastegate.
Again, the turbo I have has a A/R ratio of .8. Banks only shows a turbo with a 1/0 A/R ratio.
If mine is just a bit smaller, that might result is a little less boost, that will be fine. But, I know if I exceed 10 PSI boost on a 6.2, it won't live very long.

Parts store sold a lot of filters due to the dirt .Kids will try most anything for a boost of speed. Some kids stold Ma's nylons for filter protection.REMEMBER ??????? lol
LOU

In the 60s, my dad a sort-of rare 1963 Pontiac Lemans with a rear transaxle and a 326 V8 up front. It was rare even then (as I found out later).

I wanted to be cool, so I went to yank the air-cleaner cover off and flip it, so it would make lots of noise when I stomped on the pedal. Well, I accidentally dropped the wing nut down the carb. One of my friends said "don't worry about it", and "just nail it" and it "will clean istelf out." Well?? The engine blew to pieces. Later found bent rods, hole in block, broken crank, etc. Must be one of the "stoopidist" things I've ever done to a car. I told my dad I'd buy a used engine and fix it. Then found out, no engines to be found. Seems that 326 was used only in that Lemans and had a special crankshaft to mate the pilot tube to the rear tranaxle. I.e., no standard 326 would work. We searched for an engine for a few months and then gave up, and junked the car. Of course, that was long before the Internet, so I don't know how thorough that "national junkyard search" was.

had that happen to my 261 Chevy C-60 log truck once. Hauling logs & pulling a long hill & hex nut vibrated off & fell down the carb. Bang! Pulled over & restarted but ran with a noise so called wrecker. Later tore it down & top of piston had the imprint fo the hex nut, once full impression then impression of pieces. If I'd of keep running it very likely it would've quieted down & run ok, acording to my master mechanic & I think he was right.

had that happen to my 261 Chevy C-60 log truck once. Hauling logs & pulling a long hill & hex nut vibrated off & fell down the carb. Bang! Pulled over & restarted but ran with a noise so called wrecker. Later tore it down & top of piston had the imprint fo the hex nut, once full impression then impression of pieces. If I'd of keep running it very likely it would've quieted down & run ok, acording to my master mechanic & I think he was right.