TWM Stack Air filter

[CobraV8]

Unfortunately I don't remember whose car this is. I saved the pic on my hard disk for reference purpose with my stack injection system in mind.
I might have copied the pic from some CC thread and not the galleries, but I'm sure it is from this website.

Maybe the owner is the guy in front of the car? If this was my Cobra it would certainly put a smile on my face



Simon

[lamaluv]

Rwillia4,

I plan on doing three dyno runs, one with the present 4 brl Holley, one with the FI big filter set up and one with the individual FI filters. Running no filters is not an option for me so I'm not planning to do a dyno run without filters. The FI system in my first picture is by Imagine Injection http://www.imagineinjection.com


Dick

[800hp]

the 289 fia car is owned by larry davi in california. the k&n filters work just fine i use them on my sprint car! i have never used filters on my cobra i just made a convex screen and put it at the bottom of the stacks so you could not see it. i ran it that way for about 6 years. jim

[800hp]

fastrods with using a flat screen with round holes like that you don't have enough air flow. i used a diamond pattern then made a die so i could press it into a 1/2 round convex shape that worked very well on the flowbench. these were on a 395 ci. smallblock that made a little over 800 hp. i am going to make some for my twm here in the next week ore two if there is any interest let me know. jim

[Snakebit]

Any pictures?? I purchased a set of slip on filters that look like they cut holes in black pantihose and sewed elastic around the edges. I have not tried them yet. I,m worried they might get sucked in the carb.

[fastrods]

I hate to differ with you 800hp.
I am using a hexagonal screen which gives over 80% percent flow.
This is also the same screen and filters that Inglese uses for his weber setups.
At any rate, they work just fine on my engine.
If anyone out there is interested, let me know.
Thanks!

[aldersonjames20]

Originally Posted by fastrods

I hate to differ with you 800hp.
I am using a hexagonal screen which gives over 80% percent flow.
This is also the same screen and filters that Inglese uses for his weber setups.
At any rate, they work just fine on my engine.
If anyone out there is interested, let me know.
Thanks!

Everyone I talked to about the screens, including Inglese, told me that these will work on the street for modest driving, but that if you plan on winding out the engine on a track etc, these will not work. They do not have the surface area required to feed the air hungry monsters we use for engines. Again, they are fine for driving around and getting on it once and a while, but the reason the ugly K&N, as well as every other viable filter, have the design they do is surface area to suck air through.

James

[fastrods]

I will take a 20% reduction in airflow with my filters over a box covering my expensive stacks.
I believe that was the original question, what to do instead of a box.
The "surface area" is the same regardless of a box over the stacks or a filter over each stack - limited by the actual stack's diameter. The box still trickles down to the stacks!
I will not argue that a K&N may not flow better, I do not know that and neither do you unless you flow test both.
I do think a box with a K&N will reduce flow at least 20%, if not, I would question the efficiency of their filter, which a lot of people do.
Some of us want to show their stacks when they open their hoods and I am one of them.
James, I can appreciate your induction setup and what went into it's design - I just chose to fabricate something different.

[bobcowan]

The dyno doesn't tell the whole story - as is usually the case.

At speed (100+) there's certainly a differance between the open stacks and the oval filters. I'v tried it. I get about 8mph more on the front stretch with the open stacks, compared to the oval filters. I have not tried it with just the "tea strainers". Maybe I'll try that the next time out.

[Peo]

I have a TWM system on my 384 Stroked Clevland using their one piece F1 type filter that covers all of the trumpets. It has special foam that does not ignite but is very expensive to replace, I had to send to UK then back to Australia.The system breathes very well, and on the Dyno did not make any difference with restriction when the filter was removed or when it was left on.It is very easy to remove, it has 6 snap on screws attached to a base plate. The only disadvantage is that the trumpets cannot be seen unless the filter is removed.Motec is used with 500 rear wheel HP.I love it!

[Terry Brown]

I started with the RamFlos which work well but are not easily removed. I followed up with the K&Ns which are made for FI stacks but work well on the 48IDAs. They slip over the stack with a rubber sleeve (grommet) and are easily removed by pulling off. They are made specifically for Roush by K&N.

[Rick Parker]

When using either of these is the auxilliary venturi (tall tube in center of velocity stack) left untouched?

[Terry Brown]

Rick:

In both cases the center tube was left untouched. In the second case (K&Ns) I had to go to a 1 1/2" velocity stack to get the necessary hood clearance (older style SPF). This would not be necessary on cars after about number 1200 (approx I believe).

Terry

[Rick Parker]

Where are these Air filters purchased? Approx $$

Thanks

[Terry Brown]

Rick:

I got the K&Ns from Hillbank Motors in southern Ca. (Frank: http://www.hillbankusa.com/ 1-949-900-1966. I save all my receipts but, of course, I can't find these - about $45 ea I think.

I passed the Ramflows to Brent Mills. If he still has them he may make you a deal. They are $65 each new.

http://www.racetep.com/ramflolynx.html

Good luck!!