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Discussion Starter #1
Before anyone can say, I had to create a new profile because I forgot my password. I'll play with it later.
My question is:
How can 2 1050 carbs be too small for a 632 big chief when people are running 1400 or bigger single carb.
I'm talking the typical 632-638 1250hp standard bore spacing etc.
 

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Perhaps you would be willing to test?
I am sure someone has done back to back big inch tests?
I do recall (way back) in the 70's the small block PS guys ran double dominators - and they were nowhere near 1000 hp.
 

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Long Live The King
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At What RPM ?

Define " Too Small" ?

Air flow requirement at 7,500 @ 110% VE will be approx 1,500 cfm.

How much Vac you have with two 1,050's vs two 1,250's would be good to know. The two 1,050's might create some pumping losses because of more vac, but you won't know until you test it.

Two 1,050's should feed 1,200 hp just fine.
 

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Discussion Starter #4
The only reason why I questioned it was, the carbs were on that motor for years. Sonny's race engines use a 2300 cfm for his 1300 hp motors. So if I use two carbs totalling 2100 cfm's and loose 10 or 20 hp I can live with that. Thanks
 

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Discussion Starter #5
On a heavy 3600 lb car I would think the smaller carbs would help it get out the gate.
 

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Discussion Starter #6
I guess it's time for a bucket of trans fluid and some carb cleaner. Drop the whole carb in the bucket let sit overnight then clean it out with carb cleaner. Problems solve
 

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Just for fun.

631.524 Cubic Inches @ 7600 RPM with 108.00 % Volumetric Efficiency PerCent

Required Intake Flow between 492.5 CFM and 524.0 CFM at 28 Inches
Required Exhaust Flow between 319.2 CFM and 366.2 CFM at 28 Inches

600 RPM/Sec Dyno Test Lowest Low Average Best
Peak HorsePower 1160.3 1208.0 1231.9 1255.7
Peak Torque Lbs-Ft 876.9 913.0 931.0 949.0

HorsePower per CID 1.837 1.913 1.951 1.988
Torque per Cubic Inch 1.389 1.446 1.474 1.503

BMEP in psi 209.4 218.0 222.3 226.6
Carb CFM at 1.5 in Hg. 1500 1669 1753 1838

Target EGT= 1156 degrees F at end of 4 second 600 RPM/Sec Dyno accel. test
Octane (R+M)/2 Method = 113.2 to 115.0 Octane required range
Air Standard Efficiency = 66.69519 % for 15.000:1 Compression Ratio

Peak HorsePower calculated from Cylinder Head Flow CFM only
600 RPM/Sec Dyno Test Lowest Average Best Potential
Head Flow Peak HP = 1026.2 1143.5 1260.8
 

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Discussion Starter #11
The way things are going we might not be racing at all this year. Real talk i feel that the government is going to try to shut down drag racing all together. All type of negative press on the internet. That's how it start.
 

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Discussion Starter #12
Just for fun.

631.524 Cubic Inches @ 7600 RPM with 108.00 % Volumetric Efficiency PerCent

Required Intake Flow between 492.5 CFM and 524.0 CFM at 28 Inches
Required Exhaust Flow between 319.2 CFM and 366.2 CFM at 28 Inches

600 RPM/Sec Dyno Test Lowest Low Average Best
Peak HorsePower 1160.3 1208.0 1231.9 1255.7
Peak Torque Lbs-Ft 876.9 913.0 931.0 949.0

HorsePower per CID 1.837 1.913 1.951 1.988
Torque per Cubic Inch 1.389 1.446 1.474 1.503

BMEP in psi 209.4 218.0 222.3 226.6
Carb CFM at 1.5 in Hg. 1500 1669 1753 1838

Target EGT= 1156 degrees F at end of 4 second 600 RPM/Sec Dyno accel. test
Octane (R+M)/2 Method = 113.2 to 115.0 Octane required range
Air Standard Efficiency = 66.69519 % for 15.000:1 Compression Ratio

Peak HorsePower calculated from Cylinder Head Flow CFM only
600 RPM/Sec Dyno Test Lowest Average Best Potential
Head Flow Peak HP = 1026.2 1143.5 1260.8
Damn good information all in one post.
 

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That's from pipemax, I just roughed your deal in. Don't mind the VE, I just adjusted it in the program to get your HP at 7600 rpm and that will show needed head CFM and carb CFM.
 

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Discussion Starter #14
Just for fun.

631.524 Cubic Inches @ 7600 RPM with 108.00 % Volumetric Efficiency PerCent

Required Intake Flow between 492.5 CFM and 524.0 CFM at 28 Inches
Required Exhaust Flow between 319.2 CFM and 366.2 CFM at 28 Inches

600 RPM/Sec Dyno Test Lowest Low Average Best
Peak HorsePower 1160.3 1208.0 1231.9 1255.7
Peak Torque Lbs-Ft 876.9 913.0 931.0 949.0

HorsePower per CID 1.837 1.913 1.951 1.988
Torque per Cubic Inch 1.389 1.446 1.474 1.503

BMEP in psi 209.4 218.0 222.3 226.6
Carb CFM at 1.5 in Hg. 1500 1669 1753 1838

Target EGT= 1156 degrees F at end of 4 second 600 RPM/Sec Dyno accel. test
Octane (R+M)/2 Method = 113.2 to 115.0 Octane required range
Air Standard Efficiency = 66.69519 % for 15.000:1 Compression Ratio

Peak HorsePower calculated from Cylinder Head Flow CFM only
600 RPM/Sec Dyno Test Lowest Average Best Potential
Head Flow Peak HP = 1026.2 1143.5 1260.8
Well my 2600lb ex girlfriend went 8.04 so I guess your figures are close. Ofcourse that was the first pass off the trailer with no turning.
 

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Long Live The King
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Just for fun.

631.524 Cubic Inches @ 7600 RPM with 108.00 % Volumetric Efficiency PerCent

Carb CFM at 1.5 in Hg. 1500 1669 1753 1838
The two 1,050's should be able to handle that, but I wonder if two 1,250's would make more power ?
 

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I would try more plenum volume first by using a top spacer before trying the bigger carbs unless you just have them.
 

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Discussion Starter #18
I'm taking a break from gas. I'm putting everything on alcohol. I'm going green. If I had some 1250's I would try them. I got two mfi systems so its time out for spending money. This covid-19 is hitting the middle class hard. One mistake and you're in poverty. Ofcourse all the furniture has to go before my car.
 

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What makes you think 2 x 1050 could be too small? Is it just the comparison to the Sonnys build that you mentioned?
 
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