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Resident Ford Nut
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Even on a "mild" 460 I think I'd stick with an 850, but I guess the question(s) would be what RPM do you max out at and is it a stock intake manifold ?

Sleeper CP :D
 

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E-7 Sheepdog (ret)
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IMO you have virtually no use for anything bigger than a 750cfm'er, unless, and untill, you are spinning nearly 6-grand on that 460.

Any "horsepower left on the table", is darned little, and throttle response, "driveability" is better with a smaller carb.
 

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Is it Summer Yet?!
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I have a Holley 750, and couldn't be happier.
Don't over carb!!! Get that 750 on Craigslist.
 

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Discussion Starter · #8 ·
I decided to go with the 850.I got the one from the last post last night!!:)devilI think my program should work well for me.460 30 over ,9.5:1,comp 280h,steath intake ,850 dp,o/t bassets,msd.:D I have a t.r. 2x600 I may run in the future.This coming summer is my !st with the boat ,so I want to keep it simple.:)hand
 

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ATTA BOY
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I decided to go with the 850.I got the one from the last post last night!!:)devilI think my program should work well for me.460 30 over ,9.5:1,comp 280h,steath intake ,850 dp,o/t bassets,msd.:D I have a t.r. 2x600 I may run in the future.This coming summer is my !st with the boat ,so I want to keep it simple.:)hand
Thats about what my combo is. I have an over kill carb on my boat only becuase im going to build a bigger motor at some point. I have ran everything from a 650 to a 1050. The 850 will respond well and it wont drink a ton of gas.
 

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Already miss the 310/562
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I decided to go with the 850.I got the one from the last post last night!!:)devilI think my program should work well for me.460 30 over ,9.5:1,comp 280h,steath intake ,850 dp,o/t bassets,msd.:D I have a t.r. 2x600 I may run in the future.This coming summer is my !st with the boat ,so I want to keep it simple.:)hand
For your engine the Stealth intake is a good choice, what heads? I have a worked over 850 on my 429 CJ and like it.
 

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Discussion Starter · #12 ·
d3ve a2a,I removed the EGR humps out of the exh. ports ,crower roller rockers,crane springs,one piece crower push rods ,manley rod guide plates.
 

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Air pump......

d3ve a2a,I removed the EGR humps out of the exh. ports ,crower roller rockers,crane springs,one piece crower push rods ,manley rod guide plates.
How about doing the math for a 460 cu in air pump. Guaranteed, anything under 8K rpm is not wanting that 850...............But hey, you're only wasting gas..............Ray
 

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Discussion Starter · #14 ·
well money pit, the question was "what are u running on your 460?'' According to holley's site ,I'm pretty much in the park. not saying your wrong ,but what is the math?
I don't really get the tunnel ram thing? this boat had 2x600 cfm.doesn't that make 1200 cfm :confused: I was also told once"rule of thumb is CID x 2= cfm:)sphss
 

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Resident Ford Nut
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How about doing the math for a 460 cu in air pump. Guaranteed, anything under 8K rpm is not wanting that 850...............But hey, you're only wasting gas..............Ray
460 x 6000 rpm/ 3456= 798 cfm.

460 x 5600 rpm/ 3456= 745 cfm

Sleeper CP :D
 

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Jet = RPM

The key word is JET. An "average/decent" jet will limit the above described engine to about 5500. Now do the math. Sure 9K might like 1200 cfm, but getting to 9K from 5500 is a long way from a walk in the park. IMO, your carb size should be determined using the engine's "happy spot" as a baseline. I honestly believe a good working, properly jetted, 650DP would put you real close to what your application wants for top performance and economy. You can do wonders with slight changes in acc pump action and nozzle sizes. (AND timing curves), All engines are air pumps, and unless you have some sort of forced induction, limited by simple suck, fire, push out the waste theories. Math doesn't lie, and huge amounts of air/fuel potential flow is still governed by the size/speed of the air pump............Ray
 

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79 Sanger Picklefork
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Tunnel Ram

460 x 6000 rpm/ 3456= 798 cfm.

460 x 5600 rpm/ 3456= 745 cfm

Sleeper CP :D
I assume this formula does not change even though you have a tunnel ram? With the above formula he would be running dual 450'S..correct?
 

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www.highflowdynamics.com
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Never mind what all the mechanical pumping formulas spell out on paper; the real world dyno and engine/boat performance results clearly show that the Holley 850 is the better choice over the Holley 750 for your specific engine combo and its application. You would generate even more power with your tunnel ram w/600's...primarily at a higher rpm but still more than the 850 at the same rpm your boat will run with the single carb setup.

You made the right choice.

LO
 

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I would use an 850 with your combination. Everyone needs to remember that a Holley 850 WILL NOT FLOW 850 out of the box in "as delivered" condition. They actually flow 735-750 cfm in my experience, which "fits" the formula nicely.

RR :D
 
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