straw1628

OK guys. I have asked questions about my carb on different occasions but thought I would do it the right way this time. I took your advise and got a Holley book, which has lead me to believe my carb may be too big, (I argued with the guy that built the engine for me about that but he insisted that this be the one)

Here is my engine
66 289
.40 over
670 Holley Street dominator vac. secondaries
Edelbrock air gap intake
Mallory ignition (pertronix type in cap)
Comp cam intake=.472 exh= .486
Valves 1.86 1.6
Dual exhaust with cast iron headers

So my question is can I do enough adjusting in my carb to be good. Everything I am reading is leading to floats. Also maybe power valve, jets etc. Or would I be better of to cut my losses, sell the 670 (or shelf it for later) and get a 570-600. I would rather spend the money if it would be worth it, but if I dont have to that would be great. My main problems have been inconsistancy, bog off idle, flooding while at idle, rich mix (black out pipes) Thanks again for all the help. By the way is valvoline VR-1 racing oil I should use, correct? Thanks

blue66mustang

What power valve is installed. I'd check there if the float level is OK.

urban_cowboy

They make a 570 Street Avenger I think.

Vacuum Secondaries help hide over carb issues. Have you started trying to tune it?

I think you are over carbed, but you may can make it work if you jet down enough. It sounds like you need to adjust your bowl fuel level, idle screws, jets, pump cam, etc (general tuning). I think a 570 would be closer out of the box and easier for you to tweak than what you have.

Yes, use Valvoline VR1.

straw1628

Thats what I was wondering. We tried jets and power valve changes, but that was it. I want to re vacuum test for the power valve, adjust floats, jets etc after reading the book, it sounds like I can do alot. I am just not sure if I would get better power that way or to tune a 570 instead. Thanks. Please keep the info coming.

my77stang

the 570 is great for stock motors, but they are lacking for anything with go-fast parts on them.

i'd highly recommend a holley 600, i know the cfm isn't much different but they have larger primaries (like a normal holley should, the 570 primarys are small as hell), and they are jetted much better out of the box. plus, they are cheaper

rst08tierney

What type of Choke?

I have a very similar setup. As soon as you ditch the 670 and get a 600 or a 570 your problems will go away. If your looking for a simple and easy fix go with Edelbrock. If your in to tuning your carb and want to get the most out of it get the Holley 600.

My self, I took the simple approach and went with the Edelbrock. I had problems flooding with the 670. Right out of the box the new 600 made a difference with my idle and solved the flooding issue.

Gary H

If it's flooding all the time, check the needle valves for dirt. You might have got some dirt in the fuel lines. You should be able to get the 670 to work. Stick or automatic? If you have an automatic with stock gears, the intake is the problem along with the carb. Big carb and large plenum volumn will make it sluggish and hesitate at low speeds.

straw1628

Burnt 67 (sweet looking car by the way) I have an electric choke. Did you get more power with the Edelbrock too? Ive had alot of guys tell me to go with the Edel for simplicity, or go with Holley for more power. I dont have a problem learning how to tune the Holley, in fact I think it is fun, but I also dont want to monkey with it all the time.

Gary H, the car is an automatic. By gears I'm assuming you mean in the tranny? I did change the rearend to a 3:55 if thats what you meant. As for getting the 670 to work, would it still be better to go smaller or?........Thanks

straw1628

Any more ideas? Thanks

MonsterBilly

I have a 670 on my 289 that is .30 over. i am running stock heads with a little grinding on them and roller rockers.

My car runs perfect. the only thing i did to the carb out of the box was set the idle. I dont think the carb is to big at all. i think it is a tuning issue.

I have immidiate throttle response, no bogging, and it fires right up. I think i will post a pick.