shaker hood scoop and flow top lid, Jay or anyone

[rcodecj]

Jay, I know you dynoed a shaker hood scoop with and without an air cleaner.  The link:
http://www.fepower.net/Dyno%20Results/dyno_results_9.html
I was wondering if you had any thoughts on whether a flow top lid would help at all to straighten the air coming into the carb with a shaker.
I have ran my shaker with air filter and stock lid, and then air filter and flow top lid back to back on the street.
I could not feel any difference.
Has anyone tried a shaker and flow top lid at the track?
From what I've read the flowtop lid does not work very well when it is close to the carb top, which it has to be on a shaker because of the short air filter necessary to clear the shaker assembly. In fact the flow top lid won't work with a stock air cleaner size, a slightly shorter filter has to be used.
I was surprised to see in Jay's dyno test that taking the air filter out had no significant effect. The shaker stock air filter size is so small.  That's why I thought the flow top lid might help but again I felt no difference. Of course I doubt I can feel 5 or 10 hp anyway on the buttometer.

[jayb]

You are talking about the K&N filter top air cleaners, correct?  If I recall correctly I always ran one of those as soon as I switched to the Dominator carb, because I had to build a custom air cleaner to make the Dominator work with the shaker. Pretty sure I changed to the filter top air cleaner at the same time.  So when my Mach 1 was running 10.60s at Drag Week in 2005, it was with one of those air cleaner lids installed.

It also may be that I was running one on the dyno test you linked to, but I can't remember for sure.  The engine in that test was a different 427 stroker, and it was running a 4150 Holley carb, so it could have been with the factory lid.

I've heard in the past that those filter top air cleaner lids don't work, but I've never seen data from the track that supports that statement.  If you don't have one, the air has to curve as it enters the carb, and air just doesn't like to do that; it would rather go straight into the carb.  Especially if you have a ram air scoop, I can't imagine that one of those lids would cost you power.  Seems to me it would be better than a steel lid.

[rcodecj]

Yes, I'm talking about the K&N filter top. Thanks for the details.

[afret]

Haven't had a chance to test it at the track but you can get a different cheaper base and modify it to fit a larger and taller filter to work with the shaker midplate and scoop which should increase flow. 

Here's a photo of two '67 Thunderbird air cleaner bases and a 429 Torino shaker base on the rear left.  The T-bird base on the back right has been modified to fit a 14" diameter filter that is 3" high with the K+N lid.  The T-bird base is almost identical to the '67 390 Mustang and Cougar base and the Mustang 428 shaker base.



You can see how well the 3" filter fits in the three different bases.  From where the bottom of the filter would sit to the lip on the air cleaner base is about 1 5/8" for the stock T-bird base, 2 1/4" for the Torino base, and just about 3" for the modified base. You can see how much the 3" high filter sticks out of the different bases.







The modified base had the bottom of the air cleaner cut out and replaced with a regular aftermarket 14" air cleaner base with a rubber seal glued to the lip for a bit more height.  The '67 T-bird bases have become somewhat expensive because they can be used to make shakers but you might be able to do the same thing to other bases that will fit the midplate.   The 429 shaker base is about 17 3/8" (that seems to be about as large as you can go) compared to the 16 1/2" or so for the 428 shaker base.  You should be able to find a cheap base that is somewhere between the two in diameter and do what you have to do to get good size filter in there.  And I think you can usually find the mounting bolts/tabs that you weld to the base to hold the midplate on Ebay.

The 429 base works great on a Mustang with the cast iron CJ intake where the scoop is just a bit higher than stock.

[My427stang]

Last spring I dyno'd a 44 inch Rat motor Chevy. in a 67 Chevelle  After tuning it was about 480 to the wheels, needless to say it wasn't a shaker, but the flow top lid with a 14 x 3 K&N filter gained 5 hp or so over the same filter with a chrome lid with no significant changes to the a/f ratio.

I had also heard they didn't work by some pretty big names, but this one did OK

[jayb]

What Earl did with the one modified base is exactly what I did when I switched to the Dominator carb.  I bought an air cleaner assembly for the Dominator carb and pop riveted it on the bottom of a stock air cleaner, from a 65 Galaxie I think, and converted that for use with the shaker top.  Worked just fine for me.