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600 or 750 CFM?

Bigtime

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Just looking for opinions....
I have a 383/727/3:23 in a '65 Dodge Coronet 500.
The engine has a mild cam, headers, an Edelbrock Tarantula TM6 and [at present] a 600 CFM Edelbrock carb. It also has a standard Pertronix conversion.
I was thinking of swapping out the carb for a 750 CFM. The question is: Will I realize any performance gain [with such a mild motor] or will the larger carb hurt performance? Thanks...
 
Hello big time !
IMO I would start with the manifold, Edelbrock makes a nice more street friendly Dual plane manifold (performer RPM) that will give you more Bottom end (seat of your paints power) then a 750 carburetor or your current TM6, another Great manifold my personal all time favorite, is the Indy Dual Plane mid rise manifold, plus with a 1" spacer, another great way to tune your car is with a AFR gauge OMG this gauge can help you dial / tune your carb like a pro No B.S BTW a 750 wont hurt but I believe you will see better performance from a manifold up Grade & a 750 with your AFR.
 
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Here's the one I'm using in my car:https://www.summitracing.com/parts/atm-3379/overview/

atm-3379_xl.jpg
 
With the Tarantula, I recommend keeping the low end vacuum (and torque) up with the smaller 600 CFM carb.

i ran a Tarantula TM-5 in a 273 small block using a 600 CFM carb, but that was with a full competition Isky camshaft, four-speed, and 4.56 read end.
 
I'll be following this one. My. 030 over aluminum head 383 runs real good up top with the Holley 770 that's on it. I was debating dropping down to a 670 and seeing how it felt down low and would I lose any up top ...
 
We've been in the 12s on the 600. My bet is a Performer RPM or Holley Street Dominator would be an improvement.
Doug
 
Just looking for opinions....
I have a 383/727/3:23 in a '65 Dodge Coronet 500.
The engine has a mild cam, headers, an Edelbrock Tarantula TM6 and [at present] a 600 CFM Edelbrock carb. It also has a standard Pertronix conversion.
I was thinking of swapping out the carb for a 750 CFM. The question is: Will I realize any performance gain [with such a mild motor] or will the larger carb hurt performance? Thanks...
My opinion is that you're better off with the 600cfm. You might get a little bit of top end improvement with a 750cfm, but that would be about it. I don't think a 750cfm would "hurt", just not help that much.
 
What's the rpm range of your cam? The 600 will likely make low end tuning and performance more crisp but could hamper top end rpm's. I really don't think a 750 is big enough to hurt the bottom end though. You could always go with a 650?
 
I have a 750 CFM on my 383 it's going to smell your garage up with exhaust but top end that thing's going to scream. Buried my needle many times
 
I have a 750 CFM on my 383 it's going to smell your garage up with exhaust
True. My 383 had ( and still does) an Edelbrock performer RPR manifold with an Edelbrock 750 when I bought it. It would make my eyes water and my buddy could smell it when driving behind me. I have since re-jetted it and leaned it out a bit. It's MUCH better AND I gained about 2 MPG. That said, I almost never drive it hard enough to reach top end, so I can't comment on that aspect.
 
My opinion is that you're better off with the 600cfm. You might get a little bit of top end improvement with a 750cfm, but that would be about it. I don't think a 750cfm would "hurt", just not help that much.
Thanks....I sort of though so...the car runs good now [for what it is]. I'm just going to leave it alone for now.
 
I have a 750 CFM on my 383 it's going to smell your garage up with exhaust but top end that thing's going to scream. Buried my needle many times
I'll never get to the top end with this car...I think I am better off just leaving it alone.
 
What's the rpm range of your cam? The 600 will likely make low end tuning and performance more crisp but could hamper top end rpm's. I really don't think a 750 is big enough to hurt the bottom end though. You could always go with a 650?
I bought the car built. I don't have a cam card. I wish I did...it would probably answer my question.
 
We've been in the 12s on the 600. My bet is a Performer RPM or Holley Street Dominator would be an improvement.
Doug
I've thought the same thing about the intake. The TM6 is a top end intake IMHO. I'd be better off with a dual plane I believe.
 
I'll be following this one. My. 030 over aluminum head 383 runs real good up top with the Holley 770 that's on it. I was debating dropping down to a 670 and seeing how it felt down low and would I lose any up top ...
If it ain't broke...etc. I think I am better off with the 600, but I also believe that a dual plane intake would be a good move.
 
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