Stock Nikki Carb CFM???
06-04-07, 06:23 PM
#6
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It's very important that everyone understand that though the Sterling Carb flowed 471 cfm, this was the raw data!
Because Carl does'nt want to blow 7-12 thousand bucks on a computerized flow apperatus that controls barometric pressure, air temperature and density, he has to flow a stock Nikki before he flows a modded Nikki. He does this to "calibrate" his results on the modded carb. This has to be done because air itself is very variable. It's subject to extremely drastic changes from temperature and barometric pressure.
The first Sterling Carb flowed 429 cfm and the stock Nikki flowed 313 cfm.
This last Sterling Carb with the new venturi design flowed 471 cfm, and the stock Nikki flowed 326 cfm.
The first stock Nikki flow number just happens to be the lowest number quoted by Paul Yaw, and he has one or two other numbers listed throughout his site for the stock Nikki as well. (They are all within 12 cfm)
We "mathmatically adjust" the raw data to calibrate the finished flow rating to the lowest number flowed from the stock Nikki (313) for two reasons:
It's presumably what Yaw used for his baseline;
and because we want to confidently say "This carb will flow at least 450 cfm."
The actual adjusted number is about 452. We sell the Sterling Carb with a rating of 450 cfm.
The Holley 465 may not flow 465 cfm on cold days!
On a very warm day, it may flow well over 500!
Like I've said before, more flow is better ~up to a point~ then it's downhill from there regarding performance.
The very best combination in a carb is a flow rate roughly 1.5 times what your engine calls for @ 100% VE combined with the smallest possible venturis.
If the venturis are designed correctly, then they will flow a great deal with small diameters. This creates a very strong signal to the main circuit due to the velocity at which that incoming air is running through the booster venturi.
A good strong main circuit signal makes tuning much easier throughout the entire range and also ensures fuel delivery down low where most big-mouthed two barrels are lacking.
The super strong signal is simply bled off to obtain the right strength using the emulsion tube air jets and float level settings.
Because Carl does'nt want to blow 7-12 thousand bucks on a computerized flow apperatus that controls barometric pressure, air temperature and density, he has to flow a stock Nikki before he flows a modded Nikki. He does this to "calibrate" his results on the modded carb. This has to be done because air itself is very variable. It's subject to extremely drastic changes from temperature and barometric pressure.
The first Sterling Carb flowed 429 cfm and the stock Nikki flowed 313 cfm.
This last Sterling Carb with the new venturi design flowed 471 cfm, and the stock Nikki flowed 326 cfm.
The first stock Nikki flow number just happens to be the lowest number quoted by Paul Yaw, and he has one or two other numbers listed throughout his site for the stock Nikki as well. (They are all within 12 cfm)
We "mathmatically adjust" the raw data to calibrate the finished flow rating to the lowest number flowed from the stock Nikki (313) for two reasons:
It's presumably what Yaw used for his baseline;
and because we want to confidently say "This carb will flow at least 450 cfm."
The actual adjusted number is about 452. We sell the Sterling Carb with a rating of 450 cfm.
The Holley 465 may not flow 465 cfm on cold days!
On a very warm day, it may flow well over 500!
Like I've said before, more flow is better ~up to a point~ then it's downhill from there regarding performance.
The very best combination in a carb is a flow rate roughly 1.5 times what your engine calls for @ 100% VE combined with the smallest possible venturis.
If the venturis are designed correctly, then they will flow a great deal with small diameters. This creates a very strong signal to the main circuit due to the velocity at which that incoming air is running through the booster venturi.
A good strong main circuit signal makes tuning much easier throughout the entire range and also ensures fuel delivery down low where most big-mouthed two barrels are lacking.
The super strong signal is simply bled off to obtain the right strength using the emulsion tube air jets and float level settings.
Sterling said it was 313 CFM
06-04-07, 06:53 PM
#7
FB+FC=F-ME
It been a long time,but that sounds right.
My old Yaw Nikki had the "before and after" flow rates on the spec sheet and Im pretty sure they were a tad above 300 before and about 425 after the work.......man,that was an awesome carb!
My old Yaw Nikki had the "before and after" flow rates on the spec sheet and Im pretty sure they were a tad above 300 before and about 425 after the work.......man,that was an awesome carb!
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06-04-07, 11:29 PM
#9
well, perhaps the 364 was on a brand new factory tuned carb and teh 300cfm were on a used carb with maybe some buildup. just a thought. i knew it was 300 or in the 300's, i just didnt know the exact number. i remember reading posts from sterling.
06-06-07, 12:25 AM
#10
love the braaaap
I believe Sterling actually had a rebuilt and well cleaned stock nikki on a flow bench and it flowed about 313cfm, so no buildup in there to affect the numbers. Just look at the size of the barrels, its tiny. FYI, a sterling modded carb flows about 465, very similar to a 465 holley.
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