Cold air intakes

Topic: Cold air intakes (Read 34177 times) previous topic - next topic

Cold air intakes

Reply #45 – July 19, 2014, 02:50:45 PM

Quote from: V8Demon;436101

Right now I'm still running the 73 mm MAF, the tube that came with it, and that new filter. Drove her for a long run yesterday. I did take note of the fact that my transmission DOES NOT get hot. Warm yes, not hot. I can put the car in park after a drive, open the hood, and pull the tans. dip stick out and grip it right where the fluid is without fear of burning myself at all. I'm actually a little concerned about what's gonna happen when the cold weather comes. Time to hook up a gauge to it....

I know you just swapped the radiator. Did you plumb the external trans cooler inline with the radiator or did you just run the transmission lines to the external trans cooler? The guy who built my transmission warned me to run the transmission cooler lines first to the transmission cooler in the radiator, then to the external cooler, and back to the transmission. He said if I ran the transmission lines straight to the external cooler bypassing the radiator the transmission would run far too cool and possibly not even reach operating temperature under most cirspoogestances.

Back on topic. If the calibration tube (black, CT5/105) works for you I'm going to run the same setup. I'm going to do back to back track testing with that setup and then the stock air box and the tube for that setup (blue 102). I want to see if there is a measurable difference between the conical and the stock air box and not just a seat of the pants difference.

Cold air intakes

Reply #46 – July 19, 2014, 10:13:22 PM

I run my trans lines to the radiator cooler first then to the external cooler. The stock rad coolers are ridiculously small on these cars though.

I wish I had access to a flow bench.

Cold air intakes

Reply #47 – July 20, 2014, 08:54:37 PM

Quote from: V8Demon;436117

I run my trans lines to the radiator cooler first then to the external cooler. The stock rad coolers are ridiculously small on these cars though.

As do I on my car. The transmission gets warm but not scalding hot.

I'm still curious what difference a conical filter would make vs a K&N in the stock air box. The difference is about 100cfm in favor of the conical. How much power lost or gained that equates to I don't know.

Cold air intakes

Reply #48 – July 20, 2014, 11:53:02 PM

I think the difference is quite a bit more than that. Using the K&N formulas, a drop in as opposed to the cone I run the theoretical max flow is half. The conical has a 145 square inch area as opposed to 85. I do not know how pleat depth or amount of pleats would affect flow. One can surmise that there would be a point pf diminishing returns WRT number and depth of pleats.....

Interesting article on heating and A/C duct filtration that touches on the subject....

http://www.lacool.ws/air%20filter%20tutorial.htm

Cold air intakes

Reply #49 – July 21, 2014, 01:33:39 PM

I'm building an intake using the march racing box as well. I used K&N filter RE-0870, which has a 4" inlet to fit my 90mm MAF. It fits perfectly, and has the same dimensions as the RE-920 other than the coupler. So either filter will fit the box perfectly.
Chris

Cold air intakes

Reply #50 – July 21, 2014, 01:36:59 PM

Also, the stock box is known to support over 500hp, so I wouldn't worry about the flow upgrade so much. I'm using the march box since there was no good way to get the 90mm Lightning MAF hooked to the factory airbox without a lot of fiberglass work. Even with my supercharger install, I wouldn't be worried about the filter area.

Cold air intakes

Reply #51 – July 21, 2014, 07:34:55 PM

Which 90 mm MAF sensor are you gonna run?

Cold air intakes

Reply #52 – July 21, 2014, 07:55:04 PM

I'm going with a Ford Lightning 90mm MAF, 42lb green tops, and a tune via moates quarterhorse. Hoping for 8-10psi out of a 2.1L kenne bell.
Chris

Cold air intakes

Reply #53 – July 21, 2014, 08:49:35 PM

Quote from: a77cj7;436181

Also, the stock box is known to support over 500hp, so I wouldn't worry about the flow upgrade so much. I'm using the march box since there was no good way to get the 90mm Lightning MAF hooked to the factory airbox without a lot of fiberglass work. Even with my supercharger install, I wouldn't be worried about the filter area.

Do you know where that information came from? Someone said that it should be swapped out at the 350hp level. I don't know if that's rear wheel or flywheel though.

Cold air intakes

Reply #54 – July 21, 2014, 09:51:59 PM

I've seen builds on corral.net that were still running stock box at those power levels, dyno confirmed. Its a pretty beaten topic over there, I'll see if I can come up with a thread for ya. Remember, most of the fender-well CAI's have a filter with very little surface area gain over the panel. The March box allows for a much larger filter.
Chris

Cold air intakes

Reply #55 – July 21, 2014, 11:42:23 PM

I've seen guys run 10's on e7 heads... doesn't mean they aren't a restriction...

Cold air intakes

Reply #56 – July 22, 2014, 06:53:50 AM

Quote from: a77cj7;436200

I've seen builds on corral.net that were still running stock box at those power levels, dyno confirmed. Its a pretty beaten topic over there, I'll see if I can come up with a thread for ya. Remember, most of the fender-well CAI's have a filter with very little surface area gain over the panel. The March box allows for a much larger filter.
Chris

Exactly why I'm rocking the larger filter on the end of the MAF. Yesterday was warm and the air was thin. Not a good combo. I'm gonna swap on the stock box and the 76 withe the blue 102 tube later today and see what happens. Depending on that I may order the March box. I need a shield for the cone so.....

Cold air intakes

Reply #57 – July 22, 2014, 09:23:52 AM

Quote from: V8Demon;436210

Exactly why I'm rocking the larger filter on the end of the MAF. Yesterday was warm and the air was thin. Not a good combo. I'm gonna swap on the stock box and the 76 withe the blue 102 tube later today and see what happens. Depending on that I may order the March box. I need a shield for the cone so.....

I'm curious to see if there is a difference.

Cold air intakes

Reply #58 – July 22, 2014, 10:49:35 AM

Just some food for thought:

The hole in the fender behind the airbox measures 7"x3.5". The hole in the airbox measures 8.5"x3.5". The hole in the airbox outlet is 3.5". The diameter of the 76mm MAF and tube is approximately 3" (2.99 something). If the hole in the fender was a circle is would be approximately 4.95" in diameter (solve the are of the ellipse, work the area of a circle formula backwards to find the circle diameter) which is 125.73mm. Even the stock hole in the fender isn't a restriction. The only place there can be a restriction is the filter in the box.

Edit: My engine is a 306 that makes power to 5500rpm so it needs 81 square inches of air at that speed. The K&N panel in the stock box flows 85 square inches of air. My car is right on the cusp. If you're spinning a 306 faster than 5800rpm the K&N panel in the stock air box becomes a restriction.

So to summarize:

In V8Demon's case he should run a proper sized conical filter. A K&N panel in the stock airbox would probably rob him of some horsepower.

In my case it's a toss up. Is the stock airbox with the K&N panel a restriction? Probably not. Could my setup gain some power with a proper sized conical? Maybe.

Does your 302/306 with GT40/GT40P heads/GT40 intake/mild cam or HO cam need a big conical filter? If it's naturally aspirated no. It doesn't even need a BBK style cold air intake. Removing the air silencer and slapping a K&N filter in the stock airbox gets you the same power.

Stock 5.0 SO or 5.0 HO: stock stuff is fine.

Cold air intakes

Reply #59 – July 22, 2014, 01:50:33 PM

I still would like to see some proven flow numbers for the stock box..... If I go with a March box, rest assured that the fenderwell and box hole to it will be enlarged.