View Full Version : 19 carb intakes on the dyno. Is yours robbing horsepower?
TexasAviator
11-13-2017, 09:35 AM
Pay close attention to your air filter it could be robbing you some serious power. 19 setups that reduce or in some cases make horsepower. The ending is surprising.
https://youtu.be/EkpsydS8JXI
PeteH
11-13-2017, 09:59 AM
Thank you for posting this, that is valuable information. A salad bowl ?, who would a thunk.
Boydster
11-13-2017, 10:30 AM
I need a taller scoop.
GoDadGo
11-13-2017, 11:34 AM
Extremely Informative!
Sanford
11-13-2017, 12:38 PM
Wish they would have tested the drop base with a taller filter to have the equivalent lid height of the non drop base. I went that way to get a taller filter.
This leads well into a tuning session I just completed. It was 650HP 555CI Chevy boat engine. Single QF 850 cfm carb. I got it tuned correctly with no air cleaner, making 650 HP at 6000 RPM and 12.6 A/F ratio. I then installed his high dollar polished stainless air filter. The A/F leaned out to 13.8:1. I beat on that thing for 2 days changing jets, air bleeds and power valves and could not get it tuned acceptably. We finally gutted the air cleaner by removing some layers of the stainless mesh in it. The tune came right back into line. So the final take on this example is the engine was running lean (13.5)when we first started the testing. Had he just installed that engine in his boat and put the air cleaner on it the A/F would have been too lean and he would have most assuredly burned a hole in those brand new pistons! My thoughts are that the air cleaner base design is the most critical component. Altering the shape/direction of the air entering the carb really has an affect on metering of fuel, not just restriction air flow or not. I guess the real takeaway is always tune your engine with the air cleaner in place you are going to run.
Bob
Jim1855
11-13-2017, 01:31 PM
I agree w/ Bob, always tune with the air cleaner on. I extend that to hood down.
I've run a drop base with a 14x3. The Engine Master's test shows -7.2hp. I wish they had run the 14x4.
You may want to visit http://www.secondstrike.com/Technical/AirCleanerCalc.asp
While it may not give absolute results you should see the variation between sizes. It does not calculate for the path, velocity stacks, drop base etc.
The carb size calculator is good too but may not give you what you expect or want to see. It's designed more towards drivability rather than absolute peak power.
BTW, Mike Stenhouse at Second Strike is a good friend.
Jim
mikeinatlanta
11-13-2017, 02:29 PM
The number of times I've had an internet expert tell me that my 14X5 is way too much filter for my 700hp motor. With the ram air maybe, but my math showed a 14x4 to have very little margin, so 14X5 it is.
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