Is my carb the wrong size?

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DannyB-67
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Is my carb the wrong size?

Post #1 by DannyB-67 » Thu Oct 12, 2017 12:49 am

I have a 67 ford mustang coupe that has a 200 ci motor in it. I'v changed a few things on the motor like the headers out to a duel outlet
( suppose to be a mock v8 sound), no exhuast on the car, changed most of the lines under the hood new plugs and wires, new points and rotor in the distributor and lastly changed the carb out to a holley 500 cfm 2 Barrel from an autolite 1100 single barrel, but i wandering if the carb may not be too big. the screws came preset it says and iv got a thick 1/2 gasket under it so i know its not leaking. it takes a few turns to start and will run great when it finally gets going and is "warmed up" but just having a hard time the first time every day. i do start the car every day. its a stock fuel pump. too small of a fuel pump. anything helps thanks.
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67 Mustang, 200 CI inline six, holly 2bl, Open headers, front disc brakes, stock bottom end...Just the beginning!

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Re: Is my carb the wrong size?

Post #2 by mustang6 » Thu Oct 12, 2017 3:18 am

Clean looking engine compartment!

Some others may disagree, but I've found the 500cfm to be a little too big for a 200ci with stock internals. The 350cfm version of the same carb works better in my experience. That said, usually the first signs of being over-carbed are running rich and having a bog on lower end acceleration (which is usually masked with a larger pump shot, contributing to using even more fuel) etc. That doesn't sound exactly like what you have going on.

Some folks on this site have made the 500cfm work with careful jetting/metering/adjustments (check out wsa111's posts). Bill will probably suggest a recurve for that distributor that will help as well. If you have internal upgrades in your plans (cam, compression, 1.6 rockers, etc) then I would keep the carb as those things will also potentially put the larger carb to better use.
Scott

68 Mustang 200 ci, 250-2V head, H/W 5200, Dual Headers, Comp Cams 252H, DSII w/ MSD 6AL, T-5, V8 suspension.

65 Ranchero 200 ci, late 170 head, Autolite 1101, 3.03 3 speed, Maverick 8" 4 lug rear with 3.55 gears.

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Re: Is my carb the wrong size?

Post #3 by xctasy » Thu Oct 12, 2017 6:42 am

Is my carb the wrong size?

No.


Your "Head Like a Hole" is too small.

The problem is the short turn radius of a single 1.3" hole being feed by a two ginormus 1.6875" throttles with 1.375" venturis. Its useless trying to put 205 hp through a 125 hp hole.

Get a bigger, later head with a Direct mount 2-bbl adaptor.

The engine combination with a proper 2-bbl with a log head can still make 205 hp, though. See Crosley's direct mount Falcon modifications. Just a D7 head, some basic milling, and a nice radical 274 cam, which isn't even lumpy on a cast iron intake Ford, they still idle like an old Model T.


http://fordsix.com/forum/viewtopic.php?f=1&t=56639&p=440076#p440076.

Can't do 15 sec ET's at 88mph unless you've got 205 hp.


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Last edited by xctasy on Thu Oct 12, 2017 8:46 pm, edited 1 time in total.
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FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
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Re: Is my carb the wrong size?

Post #4 by chad » Thu Oct 12, 2017 8:24 am

I might B gettin the pic mixed up but is that a scv carb'n a non-lom dizzy?
"Big thing is only make one change at a time. Change 2 or more things at a time it becomes difficult to figure which change helped or hurt" turbo2256b » 1/16/2017
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Re: Is my carb the wrong size?

Post #5 by drag-200stang » Thu Oct 12, 2017 4:01 pm

xctasy wrote:Is my carb the wrong size?

No.


Your "Head Like a Hole" is too small.

The problem is the short turn radius of a single 1.3" hole being feed by a two ginormus 1.6875" throttles with 1.375" venturis. Its useless trying to put 205 hp through a 125 hp hole.

Get a bigger, later head with a Direct mount 2-bbl adaptor.

The engine combination with a proper 2-bbl with a log head can still make 205 hp, though. See Crosley's direct mount Falcon modifications. Just a D7 head, some basic milling, and a nice radical 274 cam, which isn't even lumpy on a cast iron intake Ford, they still idle like an old Model T.


http://fordsix.com/forum/viewtopic.php?f=1&t=56639&p=440076#p440076.

Can't do 15 sec ET's at 88mph unless you've got 205 hp.


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X2 :thumbup:
66 Mustang Coupe
200 turbo w/lenco 4-spd
stock adj. rockers, stock timing set, ARP studs
best 1/4 mile ET 9.85/best mph 139 on 8 lbs progressing to 15 lbs boost
Went 9's when 10's was fast.

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Re: Is my carb the wrong size?

Post #6 by Econoline » Thu Oct 12, 2017 10:15 pm

DannyB-67 wrote:I have a 67 ford mustang coupe that has a 200 ci motor in it. I'v changed a few things on the motor like the headers out to a duel outlet
( suppose to be a mock v8 sound), no exhuast on the car, changed most of the lines under the hood new plugs and wires, new points and rotor in the distributor and lastly changed the carb out to a holley 500 cfm 2 Barrel from an autolite 1100 single barrel, but i wandering if the carb may not be too big. the screws came preset it says and iv got a thick 1/2 gasket under it so i know its not leaking. it takes a few turns to start and will run great when it finally gets going and is "warmed up" but just having a hard time the first time every day. i do start the car every day. its a stock fuel pump. too small of a fuel pump. anything helps thanks.


I'm no expert, but I'll say a definitive yes. Could Ford's engineers have been that wrong? You've almost tripled the carb size and like X said, there's a little 1.5" hole there to stuff it through. With headers but otherwise stock bottom end. No head porting, upsized valves, etc. Afaik you have a small log head etc. Yes! that carb is way too big for your setup. Getting it warmed up should be a small affair with dialing in the choke.

What have you noticed, difference running-wise, from the old worn out 1100?
Respectfully,

Seth

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Re: Is my carb the wrong size?

Post #7 by xctasy » Fri Oct 13, 2017 5:28 am

A lot of it is that air restriction is when the carb or carb hole is the flow limiter.


Its all able to be worked out by Techncial Collage Flow Net Physics, which I did back in 1991 with a really good fluids engineer.

There is a lot in it, but the basics work out like this.

If you have a carb that has 3 sq inches of total carb venturi area, then you don't shove it down a hole less than 2 inches in diameter.

One 2" hole is 3.141 sq inches of area.

Anything less than that size is a Restrictor plate.

The stock 1-bbl carb is too small.

The stock 1.3", 1.5, or 1-3/4" hole is too small.

I think Crosley's 2-bbl carb was a 1.38" venturi carb, 2.969 squ inches of venturi are serving a 200 cubic inch engine.

Image

Or about 68 cubes per square inch.

I think that was too small, and even back in 2007, he was planning proper 4-bbl "Twin Duece" engine with two 1.38" venturi 500 cfm Holley 2-bbls for 5.938 sq inches or carb venturi area.

Which was still only the same size as the four Honda Kehin carbs Ak Miller in line six ran on the little 67 Mustang Hot Rod 125 rwhp engine.

Image


In 2007, my beloved 25 year New Zealand Automobile Association and ex Ford Machanic mate said it all.

"Ford were so smart with the in line sixes.
Restrict air, avoid engine blow ups.
Ford knew that if an I6 was air restricted, it'd be dead realiable, and they'd never have to upgrade rod bolts, valve gear, or update con rods, crank or block. It stayed the same under the head gasket from 1960 to 1983".

Even the 1982 to 1992 250 Cross flow engine had a 2-bbl Weber carb, but it had 140 cubic inches per sq inch of carb venturi area. Still a restrictor plate engine in my book. They made 131 hp, but when Ford put a 75 mm throttle body with multiple port EFI on it in 1982, the statis was 36.5 cubic inches of engine per square inch of throttle body area. The engine only made an extra 18 hp, but it had the same camshaft as the 1964 200 cubic inch US log head.

The 1971-1974 Aussie 2V's
The 1973 to 1995 Argentine 188 ME /221 SP,
The 1986-1992 HSO Tempo/Topaz/Tracer 2.3 and 1986-1992 Taurus/Sable HSO 2.5 OHV in line Fours
the 1983 to 1992 X flow 4.1 EFI,
the 1987-1997 4.9 EFI F truck and E van engine
and the 1988-2002 SOHC 3.2/3.9/4.0
The 2003-2016 DOHC and Turbo "Barra" engines were basically the same old in line sixes under the cylinder head gasket.

These were the first US syle in line six engines to operate un restricted air flow in line six.

The 4.9 EFI truck engine has just 56 cubic inches of engine per square inch of its huge two 1.85", 5.38 sq inch throttle body.

Even the first 170 HP 2V M code 250 Falcon engines had , and the very strictive Dodge 2-bbl Bendix Stromberg WW 2-bbl was only 245 cfm, and had something like 2 sq inches of carb venturi area, about 122 cubes of engine per sq inch.

In NASCAR in the Winston Cup Series Carb 355 V8 era, a "restrictor plate" was sized to be around 127 to 146 cubic inches or engine per sqaure inch of carb venturi.

Ford sized a stock in line six to have 1 sq inch of carb venturi for a 200 to 148 cubic inches.

The 200 cubic inch to 127 cubic inch per sq inch of carb "statistic" is where the engine starts to breath. As you open the old 1960 to 1968 ish C8 and before carb up form its 1.3" hole, air flow goes up. 1.416", or a simple 116 thou hone out with a die grinder, brings the airflow up. Thats what Ak Miller did in the Horsing around with the Mustang six Hot Rod articles.

We still haven't learned the basics.

But its all good, we are learnig now!.

Actually, the World Rallye Championship 122 cubic inch engine have a restrictor plate at 81.6 cubic inches per squar inch of diffuser venturi size.

Image

Image


One upstream 35 mm , or 1.38 inch hole is smacked on to the air flow side of the little 2 liter turbo engines to stop them making more than 380 hp net at the flywheel.

On a naturally aspirtated engine, 1.38 inch feeding 6 cylinders won't make more than 125 hp net at the flywheel unless you do some serious compression ratio and cam work.



So even a 350 Holley with two 1.19" venturis making 2.22 sq inches of carb area on a 200 cube inch engine...thats about 90 cubic inches of engine per square inch of or carb area.

That's a restrictor plate in my book.

Every in line six, the same. So the stock carb hole is a NASCAR style restrictor plate, right out of the factory.

Ford engineers knew exactly what they were doing.

The Offenhauser 3 carb engine with any good well sized carbs.

Just three Volkswagen carbs serves 65 cubic inches of engine per square inch of carb area. The Offy, and direct mount 500 cfm 4412 Holley are neck in neck for horsepower and air flow on a 200 cube engine.

The Faron Rhoads 14 second engine is a 25% bigger 250 engine with triple carb Offy.

Image

It is right on a the nose at 81.6 cubic inches per square inch of carb area.
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FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
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Re: Is my carb the wrong size?

Post #8 by powerband » Fri Oct 13, 2017 10:59 am

ummm,, on a simple note the 2300 series 2Bbl's are widely available and widely different. The 500 CFM 4412 is just too big for the 200 unless it's at 7K RPM most of the time. The 350 CFM 7448 version can be tuned to work well with almost any 200 but more fitting for a built engine needing lots of air.

The "1/2 4Bbl" Holley 2300 series 2bbl uses all parts of universal Holley 4Bbl's. Jetting changes with the larger venturi 500CFM 4412 may not easily get useful AFR's. The 7448-350CFM offers easier tuning for small displacement small sixes.

A good place to start tuning is the internal Power Valve with either carb. Often have with high Hg' PV's (9.5-10.5) over-enriching at light accel pedal position/intake vacuum. Dropping to lower vac PV helps prevent early enrichment in big 2bbl's on little sixes.

have fun

The 2300 is the preferred 2Bbl for modifications on my Forced Induction "research" projects.

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Re: Is my carb the wrong size?

Post #9 by CZLN6 » Fri Oct 13, 2017 11:11 am

Howdy Danny:

Given your engine package I would have to say that the Holley 500 is too big. X pretty well nailed the limiting factors as to why the carb is not fulfilling your goal. The Holley is a good carb for a direct mounted, modified engine capable of higher rpm performance. An no, a stock fuel pump is not the problem. Again, given your parameters a stock fuel pump is capable.

"it takes a few turns to start and will run great when it finally gets going and is "warmed up" but just having a hard time the first time every day."

Are you using the choke on start up? Have you tried raising the float level?

You have a good looking engine. Keep it coming.

Adios, David
co-author of the Falcon Performance Handbook
http://www.falcon6handbook.com/

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Re: Is my carb the wrong size?

Post #10 by xctasy » Fri Oct 13, 2017 9:48 pm

Not the carb, the intake.

If at all possible, do it like the late Dennis Schjeldahl's "Dennis and Dave THEORY IN ACTION " project.

Specifically the very restrictive hole under the 1-bbl carb, which people don't open up enough to clear the two barrel holes which potentially span two 1.6875 holes at a 1.875" center spacing. Opened up, that needs

a square of 1.875*1.6875 inches (3.16 sq in), plus
two 1.6875 half circles, ( one 2.236 sq)

Total is 5.40 sq inches just to serve any two barrel carb.

If it was just one hole, it would need to be a massive 2.62 inches in diameter, in fact, the same as a 210 to 235 hp Ford V8 5 liter EFI throttle body. The log head, well, its so patently lacking in area for the air fuele mix to evenly hit its six cylinder target audience.

The great Dennis and what I think will become his magnum opus.

1.14 Autolite 2-bbl. All the work was on the nasty part under the carb. That's analogous with the "gore area", where you are attempting to shove fuel into an air stream that just won't be able to bend it into the log head. Thats why everyone has trouble with 2-bbl cars as yo go up in venturi area and cfm.

The smaller carbs, the 0.98" at 190 cfm, 1.01" at 240 cfm , 1.02" at 245, 1.08" at 287 cfm, 1.14" at 300 cfm, are always reported as doing better than the 1.21" 351 cfm 1.23" at 356 cfm 1.33" at 424 cfm carbs.

The issue is evident from what the Americans and Australians discovered back in 1962...its the hole size, and although it went up, it didn't go up like
Hot 6t Falcon, the late Dennis Schjeldahl who has passed away earlier this year.

viewtopic.php?f=1&t=75757&p=583792#p583792
Hot 6t Falcon wrote:Howdy everyone from the Schjeldahl Brothers!

My brother, Dave, and I have a project head on which we are working. It is a “hex” log D8BE. We have mounted the carb flange on the log - off set to the front. So why do this??? One reason is that it is a good experiment to see if the theory of “the front 3 ports are running leaner than the 3 rear ports during acceleration or even just cruising.”

Another reason, it was a little easier, and therefore cheaper, to slide the carb forward – less welding and flatter to mill smooth. We’ll know more as we get it on the 1978 Mercury Zephyr “Z” and do some testing. Spark plug readings will tell us a lot! So will the stopwatch.

Matt Cox of Vintage Inlines sold us the carb flange, and the 302 one piece valve spring retainers and tubular pushrods for the adjustable rocker arms.

I can’t figure out how to post pictures on the TFFN or FSP. It says to post them to Photobucket??? What’s that??? Do you know how to post pictures to the forums? HELP this Old man.
Image
2bbl carb adapter.jpg
Pictures:
Image

#1 Shows the #2 intake port. The little screwdriver shows where the threads were for the original one-barrel.
1 Modified 200 intake.jpg

Image
#2 Shows where the second set of threads for the original carb threads were (near the heel of the screw driver.)
2 Modified 200 intake.jpg

Image
#3 Shows the difference between the length of the manifold to the front and the length of the manifold to the rear of the Carb flange.
3 The mock up.jpg

So why do this??? One reason is that it is a good experiment to see if all the theory of “are the front 3 ports running leaner than the 3 rear ports during acceleration or even just cruising.” Another reason, it was a little easier, and therefore cheaper, to slide the carb forward – less welding and flatter to mill smooth.

My red 1978 Mercury Zephyr “Z” coupe is PS, PB, Auto, AC. I got old, and the Falcon Ranchero from 20 years ago is worn out and too hard to drive. But the stock “smog” 200 Zephyr is just too slow, and the valve stem seals are completely shot. All of the smog equipment has been pulled.

The new carb will be an Autolite 1.14 with .059 jets. The head has 1.5” SSI exhaust valves. The stock diameter intake valves are backcut. The head was milled .065” in anticipation of a thick head gasket. This works out to a 9.0 to 1 compression.

I am also working on using an offset woodruff key in the timing gears… to alter the stock cam timing just a bit. I bought a Mister Gasket Crank/Cam Key 4 degree offset #988G. After I pull the timing chain, and gears set off an extra 1969 M 200 I have, I’ll have a better idea if the key will work. Has anyone else tried this?

The car will NOT have headers. I am seriously considering a small low pressure turbo. No more than 4 lbs. boost. That will have a “J” pipe from the stock exhaust manifold. BUT… this will come a year or so down the road. I have to move the AC compressor first.

Dennis Schjeldahl (say shell-doll)



https://en.wikipedia.org/wiki/Gore_(road) wrote:Highway exit gore.

Image

The two diverging white lines at front mark the theoretical gore, while the physical gore is the grass area that starts immediately beyond the exit sign. Highway exit gore in Gdańsk, Poland, marked with transverse lines.






All the work should go into that.

Even a 109 hp V6 171 cubic inch 2.8 liter Cologne engine in the 1979 Mustang used a 2150 Motorcraft 1.08, the ~115 4.2 and 137-140 hp 5.0 Liter V8 carb.

The little V6 with the SROD manual gearbox was just as fast as the 4.2 V8 automatic over the 1/4 mile and 0-60 mph. Its top speed was the same. The hp rating difference was 4 hp, and the torque percentage difference between the 49% bigger 4.2 was 37%, the little 2.8 had 142 ft-lb, and its bigger brother with the same carb, 195 lb-ft.

It continued with that till 1986 in feedback form in some 2-BBL V6 models (Areostar, Bronco II, Ranger )

Image

The 171 engines specs of 93 cubic inches per square inch of 2-bbl 1.08 carb is a lot better than the 139 cid per sq in spec on the 255.

To get a sharp increase in power and torque, you need to keep the 500, and just open up the area under the carb.

Even on little Pinto 2000's, the 500 cfm Holley 2-bbl always makes extra power at as little as 125 hp, and fuel economy doesn't suffer if the Power Valve, Power Valve Channel restrictions, and transition slots are tuned properly. The igntion needs to have the correct advance curve. The 500 should be everyones go to carb, the little 1.19" 350 Holley's and the smaller Autolite 2100/Motorcraft 2150's under 1.21 or 1.23 are a waste of the effort if you can find the 82 Mustang 5.0 2V GT or any old 351/390/400 2-bbl carb.


Those air flow specs and CFM and all that jazz...they have there place, but the in line sixes sweet spot is when its not air flow restricted, and you've simply got to get below the 90 cubic inches per sq in of carb venturi mark to get the benifit.

Log head to 2-bbl adaptors...great idea, and if you have to, well, its your car.

But the 2-bbl adaptors carbs never work as well as a ground out to the walls direct mount with 5.4" sq in of under carb area. That spec is 37 cubes per sq inch of carb foot print, a diifernt spec, because it excluded the 23% of area the venturi takes up.
Image
XEC Ltd ICBE's Inter Continental Ballistic Engines-
FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
X-Flow Engine Components Ltd http://www.xecltd.info/?rd=10

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Re: Is my carb the wrong size?

Post #11 by xctasy » Sat Oct 14, 2017 7:19 am

Lotsa good stuff here.


When carbs, especially bigger ones, fail to become responsive to mixture adjustment, its often because they are mounted the wrong way, and don't have the first 2 inches from the venturis un blocked for air flow.


Conventional thought in Australia is that the float bowl should face forward to the radiator. In a racing car or drag racing situation, it presents less problems. Its technically a problem because 2-bbl Holley 2300 sieris carbs, Autolite 2100's and Motorcraft 2150's have very poor air fuel distribution under idle verses wide open throttle.

Conventional thought US style is to have the float bowl pointing to the passenger side spring tower.
This is a problem especially with the small sixes offset ports which have ports for cylinders 3 and 4 widely spaced where gasoline cannot flow well.

The best options are to remount the carb float bowl into the rocker.

Photos care of cr_bobcat

Image


You then have to persue the other cable operated kick down and throttle issues that creats.

Image

Image

In line sixes, small or big six, 4-bbl or 2-bbl,

Carb position works best this way.

The Big Six guys have a whole heap more space to avoid rocker cover to float bowl clashes, and with our small sixes, its best to remove the air horn abd choke, and use another form of cold start fuel enrichment, like Percy's AdjustaJet or the Mixture Control Solenoid comon with the 2.8 liter 2150 Motorcraft carb. Choke horns mean you have no hood space if you add a spacer...you can gain and extra 1-1/2" clearance by its removal.

viewtopic.php?f=2&t=77277
xctasy wrote:Harte3 has had the best pictures but they've dropped off the list.

EFI 5.0 f truck cable is very cheep and very good and very long. 42.5" long F-250 accelerator cable is even better.


Copy the Offy C braket, and sling it under your alloy 4 hole adaptor.

care of
viewtopic.php?t=46640


Image

Image

Image

Image

Image



If you use jet extenders, you can use the later center hanger float bowl with Holleys


Image

musclecardiy.com wrote:These AED jet extensions have oval-shaped ends, which can be used without cutouts in the float

http://www.musclecardiy.com/performance ... ems-guide/

Universally, the Ford I6 suffers not because of intake runner size, but the first inches from the carb to the cylinders. Open that up to 5.4 sq inches or more, add some height, and divide it front 1-2,3 cylinders and rear 4, 5 6 cylinders if you have to.


Low rpm stumbles, carbs too big for engine...its all distibutor, toque converter and carb tunning issues, not carb size.

Seven spaces down in this table.
Image
http://s1215.photobucket.com/user/xecut ... 4.jpg.html

The common little European 1600 cc OHC engines ran the huge 195 cfm at 1.5" Hg (275 cfm at 3 "Hg) 32/36 Weber with a narrow lobe center cam and 55 cubes per square inch of carburation. That relationship copied to a proper open runner log head mod means a big 2-bbl 500 cfm carb could have its venturi sizes taken up to 1.52 inches from thr 1.375" they have stock. Carb flow goes up disproptionately to about 700 cfm at 3"Hg.

The maximum venturi size in a stock 4412 500 cfm Holley with physical venturi inserts is 1.56" with 1.75" over size throttles.

These aren't too big even for a 250 cubic in line six.

The brilliant, unlimited # 4412 2300 series based aftermarket 890 cfm C&S 1.56" (40 mm ) 2-bbl carbs would make even more, but they are illegal in circle track.

Image

There is even the Split Billet Dominator unlimited 2 barrel 2” with 1.69" (over 43 mm) venturi carbs for unrestricted V-8 2 barrel classes that outflows 890 cfm carb above for even more excellent power.

Image

Small carb theory is just that...theory.

Ford undersized i6 carbs because the were never born as performance engines....Performance F-OR-D engines in the USA were Always V8's....never in line sixes
Image
XEC Ltd ICBE's Inter Continental Ballistic Engines-
FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
X-Flow Engine Components Ltd http://www.xecltd.info/?rd=10

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Re: Is my carb the wrong size?

Post #12 by xctasy » Sun Oct 15, 2017 7:40 pm

One 1.31" venturi 1-bbl YFA Carter carb on a 4.9 F150/ E van made 114 hp in 1980.

On the little 3.3 and 4.1 engines, the same size carb, just 85 or 99 hp for 1980.

The YFA Carter and Holley 1946 were each 1.31" venturi carbs, it was what they were attached to that lost the 29 potential horses.

Question. Why was there an 85 hp 1978 to 1980 200 engine which looses 21 to 29 to hp on the other Z code 2.8 V6's (104, 109, or 114 hp depending on appilcation and year?

The German V6 came back to the USA in 1983 to 1986 with a feedback carb 2150 1.08 ( the same size as the 1979 Fox 2.8).

Answer. Well, its that blessed single 1.6875" hole under the 1-bbl carb. It was the straw the sucked the 21 to 29 hp away....

In 1960-1967, it was 1.3". Yet Ak Miller made that restriction do 100 rwhp, which was about 126 hp net at the flywheel based on manual gearbox drive train losses.

In 1968 to 1970, the carb hole was opened up to 1.5".

After that, opended up to 1.6875".

Hp ratings changed from SAE Gross J245/J607 to SAE Net J1349, and the loss was largley a paper tiger loss.

Dyno figures by Ak Miller for 1969, 1970, 71, and 1972 years many magazine publications proved it,

and the later 1980 model year figures Ak Miller and Jay Storer released for the 4.2 v8 showed the percentage losses for automatics were well in excess of 40%, 85 rwhp for a charted 119 hp engine.


Ford clearly had plans to fortify the 3.3 engine after the West German Cologne plant ended up having a huge run on 2.3 and 2.8 V6 production. About the same time(1979), strikes at Dagenham's Essex plant (which supplied the 140 hp Essex V6 3 Liter engine to South Africa, Geman and European built UK imports)

This in turn forced 2.8 V6 production to replace the British 3.0 V6.

The 1980 Federal Emissions regulations then added extra engineering requirements to German engineers to get the planned 1980-1982 2.8 V6's certified.

At the Dearborn level, Ford couldn't get an assured supply, so early 1979 was the last 2.8 Mustang, and mid 1979, the last 2.8 Mercury Fox Capri. Evidence is that the auto and manual 109 hp 2.8 was used in many Capris as an option before the 3.3 was slotted in.


Right about then (1979) the European Granada and Cortina/Taunus had a huge upward spike of 2.0/2.3/2.8 V6 engine sales, which lasted from 1978 to 1982, it basically stole all the extra production Ford USA would have liked to have.

The European V6's made between 90, 114 and 138 hp with just a 1.14" venturi Solex 34, 38 or Weber DGAS 34 or 38 carb. There were 2 liter, 2.3 and 2.8 production schedules to fullfill from a vast Koln casting and machining transfer line, which was paid for under war reparations to Ford USA

Simply on the basis of the V6 engines in Germany, for a 200 six, a 1.14" venturi carb should be your "go to" carb.


The problem is that Fords log head was cast to serve just a 1.6875" throttle 1-bbl at best.


On a pre-emptive basis, Ford USA did take instant action on the issue, as far as I can tell, in 1978.



The factory experimental 2V 200 head from 1978. I say 78 because it has the early non 1980 casting exhaust and log head component arrangements.

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Under the alloy 2-bbl Motorcraft adaptor is a 5.4 square inch area of removed iron, as cast for the Engineering team who did the dyno and emissions calibrations.

Strangely, the alloy adaptor which mounted the Motorcraft 2150 has just two 1.6875" holes, or 4.474 sq in of area under the carb. No inform 1+2 bbl coonection between each barrel.

Normal 2-bbl adaptors prior to all the later Holley Weber stuff were like this.

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I'm pretty sure the carb postion, adaptor and details in the XE head would have differed in this manner.

As far as I can tell, this item was 100% correct on the EGR and casting variations planned, but the carb looks to be a stand in. Everything else has Fords enginnering numbers etched in.

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All the other stuff for the 1978 onwards engines was tending towards feedback carbs.


I'd love to know what the 1978 XE 200 engines 2-bbl test carb was....

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I can't read the aluminum dog tag....

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XEC Ltd ICBE's Inter Continental Ballistic Engines-
FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
X-Flow Engine Components Ltd http://www.xecltd.info/?rd=10

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