I am currently running the 570 street advenger (465-510 cfm?) and I get it to work right I am going to need to buy a few more tuning parts and may still not get it very good. I ve made tons of adjustments and none seem to bring on the mains in the vac secondaries quick enough to not get a huge lean bog. I am considering getting a double pump carb. I would like to stay with Holley because I own lots of tuning stuff already.
I drive this car on the street almost daily and plan take it to the track maybe 10 times a year. It has a 3200 stall converter, 258 ci, spin it to 6000 rpm, 3.55 gear with low first (3.90 effective), total weight is 3400lbs, and I live in Florida.
Which of these carb do you recommend and why and why not the other one.

http://www.holley.com/0-80507-1.asp 390 Holley
http://www.jegs.com/i/Holley/510/0-80507-1/10002/-1


http://www.holley.com/0-80540-1.asp 600 Holley
http://www.jegs.com/i/Holley/510/0-80540-1/10002/-1

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

Honestly Bren i love my holley 390 for my car and i enjoy tuning it but as for your application mainly big cube motor the 600 might be more your type (but then again why wouldn't the 570 work unless it's just an annoying carb? i don't know the details about that carb but i like my 390) the down side my motor might be approaching becoming to much for my little 390 but i'm tuning it better and better so i'll make it work but if i had your motor i would probably step up to the 600 despite enjoying my 390 just because of certain factors. But pm me about the 390 if you want because all i know is every change i make keeps making drastic swings toward running better and better.
Have you tryed to just run the motor on the rich side to counter act the lean spell? i'm no pro like alot of the guys who have been doin this for along time but i've been solvin all my problems so i may have a few ideas

Thanks Kev

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First off Kev, nice little motor you got there. Like the color combo (Buster the Duster), but I wouldn't get to big on switching out carbs for a little while. In my very limited knowledge about carbs, bigger IS NOT always better.
Which leads to Bren's question. I've had to go smaller and smaller on my injectors to get my car to actually tune correctly. I was running what would be the equivalent of feeding a 383 to start with. I tuned down to what would be closer to a 327-350 range. I know Fopar is running a 500cfm on his slant and it really responds well. This is probably in the similar range as he ran mid 15's. So numerically and expirence-wise your carb should be running enough flow to run your engine to it's optimal level..... which leads to the problem of maybe this particular carb is a little annoying buggard.
The 600cfm should work well because it's not much bigger than what you already have, and I've seen your AFR table to agree your not dipping in. One problem I have is we ran 650cfm on the 302's and 351C so I feel like your walking a fine line, is the carb starving your engine at WOT? Frankly it makes me nervous to give the advice to get a 600cfm when my gut says your motor should be running 5XXcfm. If it is starving at WOT maybe it's the secondaries and not the carb as a whole. Which isn't there two different types of operators for the secondaries? Mechaincal and Vaccuum?
All in all I'm trying to sum up in my limited knowledge that the bigger carbs might feed and respond better, but it's been my expirence to tune a smaller carb in better than a larger one. Good luck and hopefully the carb guys will pitch in some more info. Of course you could always come over to the dark side and put EFI on...

I have limited experience with 390s, but I would vote for that out of your choices. I never got my 600 to work very well on my 64 Dart.

A 500 Edelbrock 4bbl might be better and eliminate your bog. I've used these on a couple of buildups.

Honestly, for ease of tuning and all around pleasurable driving on a Slant, the 500 2bbl Holley 2300 is very hard to beat in my book. It already has big accel pump, big shooters, center hung float, and can get electric choke. Seymour has gone 13s with this on his street car. I have gone high 14s with a mild motor in my lightwt Valiant with this carb.

Keep it simple...

Lou

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Home of Slant6-powered fun machines since 1988

I would vote for the smallest carb you can get away with. Your signals are stronger with higher vacuum.

I am running a BBD on my car.....and although its too small, the drivability is amazing. I can Idle in 1st gear.....mash the throttle and the car just scoots. I believe that having the smaller venturiies with attendent mixture velocity keeps the fuel mix well blended at all speeds.

Have you tried your car with just the primaries?

Can you get the extended pump shooters that do the secondaries at the same time as the primaries? (poor mans double pump)

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Yeah....Im the one who destroyed this rare, vintage automobile.....

I actually have found on the hpak duster the 600 is a bit large for the mild build, the 390 is a bit small... but I have a 450cfm List# 1848 that I think would be right... too bad these can't be modded to use annular boosters in the primaries (bore is too small.. but I had the local performance guy mod it and put in a set of annular 'downleg' boosters in the primaries to see how it would fare)...


THe 390 would give you best signal, consistency...I think the 600 would be a mistake... (I'm thinking the 570 truck avenger will be similar in experience with the 600...)...

-D.Idiot

I am thinking of going with the 390. My theory is come out of the hole faster and not try to make back a slow hole shot on the top end. Also should provide decent driveablity on the street.
The Holley guy thinks if I get the RPMs up quick enough it should be very aggresive on the top side. He thinks it might flow about the same as my 570 St.Advenger (450-465cfm as it turns out) because of the smoothed top and no choke air horn.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

You might also look into a K&N stubstack to help that a bit, if there's room under the hood...


-D.Idiot

I 've got zero room. Really I've got less than zero room. My air cleaner kindof rubs on the hood mat. I had thought about angle milling the intake to head surface and the carb adapater to match.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

i'm thinking of trying the 0-90470 holley on my engine. 600 is too big and 390 too small. anyone using the 470? ron

What about a spreadbore?

Tiny primaries for economy

and

Huge secondaries for power.


Holley has a 650 spreadbore replacement for quadrajets.......

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

http://tinyurl.com/2wg98v
Check out this carb. Does it look familar?
Yup thats a 470 Truck Advenger (0-90470)
100% hated this carb. No matter what it did it left a black cloud well after the accel pump was drained. It was ing.

A friend (kindof) wants to buy it for his truck. SOLD, but I won't help you set it up.

I ll have to put all the parts back in to it before he picks it up.
I stole the jets, nozzle, cam, vac spring.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

I have two different 390 Holleys, a 600 VS, and a 600 DP. On motor only they are all about equal, but the 600 VS was a little slower, but the car stayed more consistent during the day and into the night. On the hose, they are all equal.

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Official Cookie and Mater Tormentor.

I am getting one tomorrow and read this in the online instructions.

SPECIAL NOTE: Part number 0-80507-1 is shipped from Holley without the high-speed air bleeds to allow for the Touring Series Style
racing calibration. See the air bleed section for clarification and identification of the high-speed air bleeds.

What air bleeds are you running?

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

bren ,thanks for heads up on the 470. since i live on lake chargoggagoggmanchauggagoggchaubunagungamaugg (yes 45 letters,world record) and repair inboards, i have a known good used 0-80364 450 cfm from a boat. i will test that one instead of buying a new 470 and see how it works for my engine combo. ron