Got the carb bug...but have a few needs

[Redfish]

So, the trip to Carmel and the Shelby tribute has given me the retro bug. Not sure if I'm ready to go down this path, but been thinking about switching from EFI to carb...dual quad carb. Edelbrock offers this complete kit, roughly $1200.


But, I 'need' to make about as much power as I make today...this is where the issue resides. Currently setup with a stock 302 longblock with explorer intake and vortech blower...pushing 316 to the wheels. Just right for me.


So, keeping on a budget, I'd sell the blower setup, EFI and I have a tubular GT40 intake to put up as well, so I can make some funds, but nothing crazy.

I've been reading a lot of forum and internet reviews, does not appear the 302 will produce this type of power without either a stroker kit or significant mods.

Thinking I would get a nice set of heads ($1400?) with the dual quad intake setup, with plans to do a 331 / 347 down the road.

Am I crazy? Should I just put on the GT40 intake and forget it?!?!?

[CobraDVM]

Those Edlebrock carbs will be a PITA on a 302 in a light car. I had them on a 408 and they sucked. If you want to go carbed, get a QuickFuel carb - they run great right out of the box. But you will not get the same power from a supercharged 302 compared to a naturally aspirated 302. You will need to stroke it or go to a 351 based build to get equivalent power.

[Mike Brasfield]

Been there done that. I started out with a pretty mild 302 EFI. Went to Victor Jr intake and increased the HP. Decided to go carb so I replaced all with AFR heads, Edlebrock dual plane intake, custom carb (780) by pro-systems a few other goodies and pushed it up to 425hp. I would strongly recommend you go with a single rather than duel carbs. Also, you'll need to change the fuel system going from EFI to carb. Good luck.

[edwardb]

Agree with the last two posts. Most on this forum report issues with the Edelbrock carbs on these cars, and I would stay away from dual carbs. Cool bling factor, but question the benefit and effort required to set up.

I'm running a single Quick Fuel SS-650 on my 306. Couldn't be happier with it. I have AFR heads, Comp Cam rockers, lifters, cam, forged pistons, and Edelbrock Air Gap intake. Hasn't been dyno'd, but it's very strong and perfect for how I drive the car.

[Stinson Pilot]

I had an Edelbrock AVS 650 on my 302, never could get the hesitation out of it. Others here have had the same problems.

Changed to a Holly Street Avenger 570, all better now. Has more power and no hesitation.

[Xybram]

There are several people here that are running that dual carb setup and they like it,

Here's one
Carb tuning advice needed...

If that's what you want do a search and go ask these people how they like it and would they do it again. The look is absolutely KILLER. There has been a lot of documentation about edlebrock carbs difficulties on these cars. I believe most of it rises from the vacuum secondaries. I don't recall anyone throwing out their dual quad setup so it may solve the hesitation issues over the edelbrock single carb.

If you change your mind and go single carb, The Quickfuel SS-650 is fantastic for your motor.

To get the power you have now and even more you'll need aluminum heads and a new cam shaft to go along with the new carb setup. That'll easily give you the power your looking for.

HTH
Chris

[Jim Doak]

I went from a single four barrel to a dual quad setup. But instead of an Edelbrock intake and carbs I'm running a Blue Thunder intake and Holley carbs.

I primarily did if for the looks, but I also like the way it runs. But you won't make as much power as you will with the Vortech.

[Greg_M]

Originally Posted by Stinson Pilot

I had an Edelbrock AVS 650 on my 302, never could get the hesitation out of it. Other here have had the same problems.

Changed to a Holly Street Avenger 570, all better now. Has more power and no hesitation.

Exact same experience. I ran a tweaked 570 for years and recently switched to a Holley #4776, 600 double pumper and love it. The only change I made was to drop the secondary jets from #73 to #70. This carb runs great and dispels any concern about poor mpg with this DP when driven normally. On my 90 mile mixed driving loop the carb made an almost unbelievable 24.5 mpg or 1.5 mpg better than the 570. The reason is, it has a very broad operating range where AFR is an economical 13.8 - 14.7 :1. Transition to the secondary is smooth and WOT rips at 12.3 AFR.

I don't think any dual or exotic carb would perform better on my car.

Greg

[Redfish]

Thanks guys, appreciate the quick feedback. Interesting feedback on the Edelbrocks...I definitely don't need to have the Edelbrocks. The dual quad manifold is available on its own, then I could add the carbs of choice. Doesn't appear that quickfuel makes a 500cfm, but I'll look again, everyone seems to speak very highly of them.

Definitely trying to keep up the Wow factor, from the blower to something as cool, hence the potential dual quad. I'm not shy to swap out the heads, cams, etc to make the equivalent horsepower. A 331 seems pretty straightforward as well.

Buying the quad setup separately gives the opportunity for separate air cleaners...love that look.

[Redfish]

Other idea I had was keep the blower, switch to carb...quickfuel blow-thru carb. But not sure that gets me the look I want with the bonnet hat...and have not read good things on the carb enclosures.

[Redfish]

Mike - did you run a stock bottom end and achieve 425hp? Thanks.

Originally Posted by Mike Brasfield

Been there done that. I started out with a pretty mild 302 EFI. Went to Victor Jr intake and increased the HP. Decided to go carb so I replaced all with AFR heads, Edlebrock dual plane intake, custom carb (780) by pro-systems a few other goodies and pushed it up to 425hp. I would strongly recommend you go with a single rather than duel carbs. Also, you'll need to change the fuel system going from EFI to carb. Good luck.

[CraigS]

Do some searching on dual carbs. There have been a few guys who have done it and are happy. The one problem I have seen is the carb size. I could have missed something as this isn't something I've researched, but I think the minimum size is a 390. So double that is 780 cfm which is definately on the large side for a 302. A couple of friends w/ 347s have gone from a 750 to a 650 to get more torque and better driveability. So research carbs, probably stay away from Edels and look for a model that everything is a replaceable jet not a drilled hole in the body. And try to find one w/ replaceable venturies too. this will help being able to get a good tune.You can certainly get similiar power to what you have now but the curves are going to be different w/ both hp and torque coming in at higher rpm.

[5.8Cobra]

Say it isnt so!!! I got dibs on the supercharger if you decide to ditch it. Also I have a great machine shop should you decide to add some cubic inches. Keep me posted....

Mike

[Avalanche325]

Dual carbs look good. That is about all that is good about them.

If you want people to say "Oooooo" why don't you go nuts and put four Webers on?

[Lex]

I ran this set up. No hesitation, set it and left it alone. 2-450 holleys and I put the whole system together for about $800.00. As far as horsepower, I have it on a 302 with GT40P heads and a B303 cam and I don't know #'s but it runs alot better than a single 650DP did. As far as doing it again, if I had the hood clerance on my coupe the same set up would be on it.




Heres a video of it

[Redfish]

Thanks Craig...this is the kind of guidance I need, did I mention I know nothing about carbs either! So, not only would this be a retro-fit, but a learning experience as well.

Originally Posted by CraigS

Do some searching on dual carbs. There have been a few guys who have done it and are happy. The one problem I have seen is the carb size. I could have missed something as this isn't something I've researched, but I think the minimum size is a 390. So double that is 780 cfm which is definately on the large side for a 302. A couple of friends w/ 347s have gone from a 750 to a 650 to get more torque and better driveability. So research carbs, probably stay away from Edels and look for a model that everything is a replaceable jet not a drilled hole in the body. And try to find one w/ replaceable venturies too. this will help being able to get a good tune.You can certainly get similiar power to what you have now but the curves are going to be different w/ both hp and torque coming in at higher rpm.

Yeah...I know Mike...I may be a little crazy on this one. Hard to give up the blower and the easy power.

Originally Posted by 5.8Cobra

Say it isnt so!!! I got dibs on the supercharger if you decide to ditch it. Also I have a great machine shop should you decide to add some cubic inches. Keep me posted....

Mike

Avalanche - the Webers would be nice, but the price tag is out of my league vs. the dual carb (see Lex's comments on the $). Don't get me wrong...would love 'em!

Originally Posted by Avalanche325

Dual carbs look good. That is about all that is good about them.

If you want people to say "Oooooo" why don't you go nuts and put four Webers on?

[Redfish]

Now we're talkin'! Lex - that is a beautiful setup, and would be what I'd shoot for.

I clicked on your links...looks like you are running a blue thunder intake w/ the Holleys...? I'll have to check that out. May PM you if / when I get more serious, thanks!

BTW, sounds good too!

Originally Posted by Lex

I ran this set up. No hesitation, set it and left it alone. 2-450 holleys and I put the whole system together for about $800.00. As far as horsepower, I have it on a 302 with GT40P heads and a B303 cam and I don't know #'s but it runs alot better than a single 650DP did. As far as doing it again, if I had the hood clerance on my coupe the same set up would be on it.




Heres a video of it