Carb Recommendations

dad and I were thinking about replacing the carb on the 71 Mach 1. The car has been running ok, but not to expectations. It seems to have good days and bad days. When I parked it in the garage last, it was chugging some black smoke and soot out the pipes. Other days, it ran clean and clear. Previous owner also indicated that he had some trouble with the old carb, so we are going to put a new one on her!

So what do you guys recommend? She has a 302 built to 306 with an mild/unknown cam, hydraulic lifters and 289 heads. Looks like a standard Edelbrock intake and long tube headers. This car is a weekend cruiser, no need for track tuning. We just want some good power and smooth running!

We already have a few choice selections in mind, but I want to hear some thoughts from the 71-73 community!

Holley 670 SA

dad and I were thinking about replacing the carb on the 71 Mach 1. The car has been running ok, but not to expectations. It seems to have good days and bad days. When I parked it in the garage last, it was chugging some black smoke and soot out the pipes. Other days, it ran clean and clear. Previous owner also indicated that he had some trouble with the old carb, so we are going to put a new one on her!

So what do you guys recommend? She has a 302 built to 306 with an mild/unknown cam, hydraulic lifters and 289 heads. Looks like a standard Edelbrock intake and long tube headers. This car is a weekend cruiser, no need for track tuning. We just want some good power and smooth running!

We already have a few choice selections in mind, but I want to hear some thoughts from the 71-73 community!

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It could be as simple as choke adjustment or fuel contamination The new gasahol is hard on old fuel line. But, if you want a new carb for your cruiser consider Holley PN 80570 (570 cfm/$356.00). It should give you the outcome you want. You will need to order the ball stud and other small parts to connect throttle cable and kickdown (Holley PN 20-91). It may come with the fuel line and fittings to connect the primary and secondary fuel bowels to fuel pump line, it will connect on the passenger side (Chevy past influence). The kickdown linkage adaptor on Edelbrock is an ugly nightmare contraption so I'd stay away from edelbrock. Another option that I've not used but would be a good fit is the "Summit" carb PN M08600VS (600 cfm/$260.00). The Summit carbs are an updated version of an out of production Holley carb that in turn was an updated version of the Autolite 4100 carb. These things are very simple, reliable, and those that have them say they work well.

Good Luck,

Chuck

My dad found a Holley for around $270 that is supposed to be a direct fit for Ford...maybe that is what he was talking about. I have to do some research to see. Sounds like a good recommendation though!

here is a pretty cool link that might help also

http://www.gtsparkplugs.com/CarbCFMCalc.html

here is a pretty cool link that might help also

http://www.gtsparkplugs.com/CarbCFMCalc.html

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Thanks for the link, Roy. I'll bookmark this thread, since I'll be moving into the intake/carb decision-making process soon.

Doc

Nice link. X2 on the Holley street avenger.

I like the look of the FAST EZ EFI system.

You've probably already gone with your Holley solution, but kick-down linkage aside, I would still recommend an Edelbrock 1406 (600CFM)... simply for the fact that it's so easy to tune and there are no main body seals or gaskets living in direct contact with standing gas - meaning no fuel or other chemicals will help along the demise of the main body seals. This is huge if your car will be sitting for any long periods of time (i.e., during winter hibernation for some areas). As a result, they are also WAY easier to rebuild as well - the only carb easier to rebuild being an MC2100-2150 (in my book, anyway).

BTW - for those unaware, the historical significance of the word "carburetor" is that it was originally a French word that loosely translated actually means, "Don't f00k with it."

Barry Grant 625cfm Road Demon with vac. secondaries should also be a great choice for street driving and performance

It's basically a double pumper with smoother air entry, 4 corner idle, clear sight windows, billet etc. with a simple to work on design.

Based on this calculation, just for example: 306ci x 6500rpm divided by 3456 your engine would require a minimum of 575cfm.

Barry Grant 625cfm Road Demon with vac. secondaries should also be a great choice for street driving and performance

It's basically a double pumper with smoother air entry, 4 corner idle, clear sight windows, billet etc. with a simple to work on design.

Based on this calculation, just for example: 306ci x 6500rpm divided by 3456 your engine would require a minimum of 575cfm.

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I don't think the engine has ever seen any rpms over 3000 with the 3 speed C-4! LOL! It must have a 600cfm on it now. I think we are going to pull it and see what it looks like this weekend. Dad wants to try and rebuild it first and then go from there! The Road Demon does sound good though!

If you have any access to an ultrasonic cleaner, use it. They do an amazing job.

If you have any access to an ultrasonic cleaner, use it. They do an amazing job.

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We have one at work they do work well.