Author Topic: What size carb should be on my 440?  (Read 14478 times)

Offline all4rocks

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What size carb should be on my 440?
« on: June 22, 2013 - 09:03:54 PM »
I got a 70 cuda with a stock 440. This is a U code car and non numbers matching.  Right now it has a 750 Edelbrock carb on it that needs rebuilding. I am debating to just get a new holly or ?. Is that the proper size for a stock 440? What kind and size works good?




Offline Chryco Psycho

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Re: What size carb should be on my 440?
« Reply #1 on: June 22, 2013 - 09:59:17 PM »
I use 2x the CI , so 850 & proform would be my top pick

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Offline cudabob496

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72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline AMXguy

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Re: What size carb should be on my 440?
« Reply #3 on: June 23, 2013 - 12:13:42 AM »
Three  two barrel Holleys. 
1970 R/T SE Challenger
 1970 Superbee
 1969 S code Mach 1
 1967  GTO

Offline Strawdawg

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Re: What size carb should be on my 440?
« Reply #4 on: June 23, 2013 - 12:17:27 AM »
850 cfm is what works

the new models are much easier to tune for wot as well as cruise and idle.

Offline all4rocks

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Re: What size carb should be on my 440?
« Reply #5 on: June 27, 2013 - 03:21:20 AM »
What model proform? vacuum or mechanical secondaries? My car has an auto trans if that makes a difference.
I already have a holley street dominator intake manifold coming for it.
« Last Edit: June 27, 2013 - 03:23:46 AM by all4rocks »

Offline cudabob496

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Re: What size carb should be on my 440?
« Reply #6 on: June 27, 2013 - 03:37:21 AM »
from Holley.com

QUESTION How do I know if a vacuum or mechanical carburetor is best for me?
ANSWER For street cars the vacuum secondary carburetor works best on midweight or heavyweight cars with an automatic transmission. They are more forgiving than a Double Pumper is because they work by sensing engine load. The mechanical secondary carburetor is best on a lighter car with radical camshaft and a lower gear and manual transmission or on a car that is going to be used for racing purposes. Here are some additional resources for you to see on Holley TV. Overview Of 4150 Vacuum Secondary Carbs Click Here To View. Overview of 4150 Mechanical Secondary Carbs Click Here To View.
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline all4rocks

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Re: What size carb should be on my 440?
« Reply #7 on: June 27, 2013 - 08:57:52 AM »
ok so what model preform should I get?

Offline Strawdawg

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Re: What size carb should be on my 440?
« Reply #8 on: June 27, 2013 - 09:51:40 AM »
What model proform? vacuum or mechanical secondaries? My car has an auto trans if that makes a difference.
I already have a holley street dominator intake manifold coming for it.

What cam, what compression, what rear gear ratio, and what stall is your torque converter?  Are you looking for best gas mileage or best performance?

Offline Haddixj

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Re: What size carb should be on my 440?
« Reply #9 on: June 27, 2013 - 10:18:33 AM »
Which car did you end up buying? Did you ever post any pics of it?

Offline all4rocks

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Re: What size carb should be on my 440?
« Reply #10 on: June 27, 2013 - 09:49:57 PM »
1970 stock 440 u code with stock heads stock compression stock cam and stock torque converter. I am just looking for more performance.

Offline 72cudamaan

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Re: What size carb should be on my 440?
« Reply #11 on: June 27, 2013 - 09:58:34 PM »
Best bet would be a 850 vac. secondaries.
If I cant fix it, it's broke
 
Andy  (phukker whither)

Offline Strawdawg

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Re: What size carb should be on my 440?
« Reply #12 on: June 27, 2013 - 10:05:00 PM »
Best bet would be a 850 vac. secondaries.

sounds good to me

Offline all4rocks

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Re: What size carb should be on my 440?
« Reply #13 on: June 27, 2013 - 10:15:44 PM »
The Proform website shows 2 850  carbs, one race series and 1 street series.
both have
mechanical vacuum secondaries. Don't they make one with vacuum secondaries?

Offline Chryco Psycho

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Re: What size carb should be on my 440?
« Reply #14 on: June 27, 2013 - 11:13:52 PM »
I am not sure they do have a vacuum 850

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