What type/model carb(s) are you using?

ZOERA-SC7XX · #1 (**permalink**) 06-08-2010, 05:50 PM

Seeing all the carb problems popping up (no pun intended) and issues with carb tuning (my own included), What carb or carbs are you using and what are their advantages and/or disadvantages?

Silverback51 · #2 (**permalink**) 06-08-2010, 06:01 PM

I'm using Holley 660 CFM carb's with center squirters and mechanical secondaries.

While mine do work well, I would not recommend them unless you have someone with a dyno, and a lot of experience to work on them.

mdross1 · #3 (**permalink**) 06-10-2010, 11:37 AM

Always used Holley's Dbl pmp 850 cfm on big blocks.Just got a carb from Dan Davinci a 1000cfm modified dbl pump Holley.My only complaint about the dbl pmp was the rich idle.The new Davinci carb address's this along with giving the motor all it wants for fuel.

SuperHart · #4 (**permalink**) 06-08-2010, 06:28 PM

Since I am running a 351W with Price dual quad intake which is set up for cruising rather than racing, I chose a pair of Holley #8007 390 cfm carbs. I enrichened the primary jets by 2 numbers, no other modifications made. Personally, I like the way they perform as I prefer vacuum secondaries over mechanical.

Bob In Ct · #5 (**permalink**) 06-08-2010, 06:33 PM

Holley 4160 model R80508 (750 CFM single pumper) on a 351W - Electric choke, vacuum secondaries. No issues for 10 years.

Bob

dcdoug · #6 (**permalink**) 06-08-2010, 06:36 PM

Holley 4160 3310 on my FE. 750 CFM, vacuum secondaries, about as easy to tune as carbs get. I am considering putting on an original Holley 3255 with Lemans bowls, but I am hoping for a better experience than Elmariachi had...

elmariachi · #7 (**permalink**) 06-08-2010, 11:15 PM

I have a Holley 3255-1 LeMans and am now in therapy.

lovehamr · #8 (**permalink**) 06-09-2010, 07:07 AM

Doug, why don't you just put the LeMans bowls on the 3310?

dcdoug · #9 (**permalink**) 06-09-2010, 08:14 AM

Quote:

Originally Posted by lovehamr

Doug, why don't you just put the LeMans bowls on the 3310?

Originality.

I wouldn't want to do it only part way if I am going to do it. I even prefer to have a date code original rather than a repop from Holley which are essentially exactly the same other than the repop only has the model and list numbers and not the date code.

I might be coming a bit obsessive...

Sort of like Rodknock and his Hallibrands.

RodKnock · #10 (**permalink**) 06-09-2010, 09:49 AM

Quote:

Originally Posted by dcdoug

Originality.

I wouldn't want to do it only part way if I am going to do it. I even prefer to have a date code original rather than a repop from Holley which are essentially exactly the same other than the repop only has the model and list numbers and not the date code.

I might be coming a bit obsessive...

Sort of like Rodknock and his Hallibrands.

Uh, if you're looking at date coded original carbs with lemans bowls, then I think you're a little further right on "the spectrum."

FIA-ERA · #11 (**permalink**) 06-09-2010, 08:17 AM

Quote:

Doug, why don't you just put the LeMans bowls on the 3310?

Yep, that's what I did! I took a 1850 600cfm and put LeMans bowls on it! Now of course if you look at the id number you can tell but it looks and acts the part! The only people that even know what it is, is a real Shelby nut! Most people think it's a bogus Holley or Quadrajet... My buddy races a 65 Shelby with a 750 double pumper with LeMans bowls too. He just uses two bowls with accelerator pumps. Works REALLY well and totally fits his period correct car! Carl's ford has them ready to go. Matt

Zoom This · #12 (**permalink**) 06-09-2010, 11:58 AM

Fussed with an 850 Holley for way too long before settling on a Barry Grant Mighty Demon 650 cfm. Modified the jetting and added jet extensions. Works absolutely great on my 418W. Gave up 15 hp at the top end for 19lbs torque in mid range with this setup.

ratsnst1 · #13 (**permalink**) 06-10-2010, 09:13 PM

Quote:

Originally Posted by Zoom This

Fussed with an 850 Holley for way too long before settling on a Barry Grant Mighty Demon 650 cfm. Modified the jetting and added jet extensions. Works absolutely great on my 418W. Gave up 15 hp at the top end for 19lbs torque in mid range with this setup.

I called barry grant tech dept, about my car stalling under extreme hard braking to a stop, they said to lower the front fuel bowl to a quarter of the site glass, and the rear at the bottom of site glass, and damm it worked, alot of people told me raise the float levels to the upper portion of the site glass on both bowls, and use the jet extensions, what were your problems and how did you fix.thanks rob.

Excaliber · #14 (**permalink**) 06-09-2010, 01:15 PM

BEFORE Le Mans bowl carb's, in 65 or so, Holley did not have any center pivot floats.

Jump ahead to today. Holley center pivot floats of an entirely new design are readily available. The center pivot concept is specifically for addressing the needs of road racing G forces acting on the fuel bowl level. "Off roaders" whose vehicle may be subject to extreme angles would also benefit from this.

Problem for some of us is, you can't run ANY center pivot float on a dual four intake manifold without clearance issues between the two carbs. I've run three different Holley carbs on my dual intake, they ALL had the same problem: Float level to high or to low under extreme cornering conditions. None of them was center pivot of course.

I'm not sure anyone makes a side pivot float carb designed for road racing, or off road use, that will fit on a dual carb intake? If so, I'd buy 'em!!! I can't find anything that works well for auto cross on a dual intake. And I've spent a bunch of money trying, did a bunch of modifications, it aint working.

era427tp · #15 (**permalink**) 06-09-2010, 02:15 PM

I run a Holley 850,modified to 930 CFM by BoLaws.The choke horn is milled off and I'm running 83 jets all around.

undy · #16 (**permalink**) 06-09-2010, 04:21 PM

I'm running a pair of custom built QuickFuel 750s built expressly for my 482 setting on a ported and shaved Dove Tunnel Wedge. First time with them on the chassis dyno and AFR was 12.5 @ WOT. They work PERFECT.

Notice the stainless steel intake manifold "stud kit". No more stripped out aluminum head threaded intake manifold bolt holes.

ERA Chas · #17 (**permalink**) 06-09-2010, 07:21 PM

Quote:

Originally Posted by undy

I'm running a pair of custom built QuickFuel 750s built expressly for my 482 setting on a ported and shaved Dove Tunnel Wedge. First time with them on the chassis dyno and AFR was 12.5 @ WOT. They work PERFECT.

Dave, How far do the secondarys open at WOT on your 482? What are the cam specs and valve sizes?

undy · #18 (**permalink**) 06-10-2010, 04:18 AM

Quote:

Originally Posted by ERA Chas

Dave, How far do the secondarys open at WOT on your 482? What are the cam specs and valve sizes?

On the chassis dyno they were 100% open by the end of the pull. On the street (not track) I probably don't have enough road to keep my foot in it long enough to get them both open, at least without fear of incarceration. I'm running Blue Thunder's re-pop version of the OEM progressive linkage. Acceleration through the RPM band is very linear with no flat spots or bogs, overall I'm very pleased.

The cam is a KC/Comp Cams hydraulic roller, 242/248 w/ .644 int, .633 exh

The cam's pretty tame as I can cruise at 1300/1400 RPMs w/no bogging or bucking. The idle's a different story, a bit radical (as I like it).

2.19" intake with 1.76" exhaust on the valve sizes... KC's stage II Ebok heads.

ERA Chas · #19 (**permalink**) 06-10-2010, 07:52 AM

Quote:

Originally Posted by undy

On the chassis dyno they were 100% open by the end of the pull. On the street (not track) I probably don't have enough road to keep my foot in it long enough to get them both open, at least without fear of incarceration.

The cam is a KC/Comp Cams hydraulic roller, 242/248 w/ .644 int, .633 exh

2.19" intake with 1.76" exhaust on the valve sizes... KC's stage II Ebok heads.

Thanks for the reply. I have 55 inches less displacement and wanted to compare our data.

The dyno's brake load helped get your secondarys full open.
At the dragstrip, I could get mine fully open but 2/3 that on the street, even given a lot of room.

Our cams are very similar but mine is solid and has more exhaust duration. My Shelby heads have 2.250 intakes.

Your 482 uses all 1500 cfm of breathing, my 427 breathes 1308. I wish I knew how but I'd like to know the VE of both our engines. Does using all the cfm mean 100%?

Thanks for sharing.

Silverback51 · #20 (**permalink**) 06-10-2010, 01:49 PM

Quote:

Originally Posted by undy

I'm running a pair of custom built QuickFuel 750s built expressly for my 482 setting on a ported and shaved Dove Tunnel Wedge. First time with them on the chassis dyno and AFR was 12.5 @ WOT. They work PERFECT.

Notice the stainless steel intake manifold "stud kit". No more stripped out aluminum head threaded intake manifold bolt holes.

That's the first time I have seen them mill off the fuel vent tubes.

Must work well for you.