2 bbl Tuning

See this https://www.youtube.com/watch?v=5hwp5-W8jl0



https://www.youtube.com/watch?v=r-yFvunHGVk

2100 to 2150 transitions had some extra features.

One of them was the 2 stage Power valve, which not manny understand. The issue is that the power valve channel restriction floods the engine in a too rich condition. If you use the 2 stage power valve, you'll have some extra adjustability. To fit it, you need a bigger 2150 power valve holder boss.



http://www.therangerstation.com/tech_li ... 0_carb.pdf

Motorcraft 2150 Carb Body Plumbing Bronco II & Explorer Specific. ... 1985 Ranger, stock 2.8l V6, 5 spd, desmogged .... One thing you might check is the power valve , they like to leak and will cause an over rich condition, ..

Click to expand...

http://vb.foureyedpride.com/showthread. ... ower-valve

http://vb.foureyedpride.com/showthread. ... wer-Valves

Two stage power valve is a Ford Motorcraft/Holley idea, found ex 4-bbl 4180c and later Jeep and Ford 2150 Motorcraft 2-bbl carbs.

Motorcraft CE-126 is a common two-stage power valve that I'd suggest.

http://grantorinosport.org/BubbaF250/carb/carb10.html

See http://www.carburetor-parts.com/Carbure ... _p_62.html

Holley 4 barrel and Motorcraft two stage power enrichment valve. Please be aware that you cannot replace a 1 stage valve with a 2 stage without replacing the valve cover with a larger one.

Price includes 1 power valve only.

When the engine is at idle the vacuum is at the highest and the power valve (enrichment valve) is closed. As the engine speeds up vacuum drops and the power valve opens allowing more fuel into the carburetor.

On a 2 stage power valve such as these, the 1st stage opens up at a certain vacuum, i.e. 7,0 HG. This is at partial power. At close to full power the vacuum drops to very low HG, i.e. .5. This is where the 2nd stage opens allowing even more fuel to get to the main circuit.

The carburetor kits that include a 2 stage power valve are using OE specifications.

For other applications you will need to test the HG by hooking a vacuum meter to the engine and operate the engine at power and full power.

Changing from a 1 stage power valve on a carburetor that requires a 1 stage, to a 2 stage power valve. Is not recommended. If you aren't sure of what you are doing, you could cause too much fuel to be dumped into the carburetor.

Click to expand...

As stated, it requires a later Jeep 2150 or carrier to hold it, and you may have space limitations if you have a carb adaptor, but the 2 stage power valve often helps soften the transition to the large power valve channel restrictions on small sixes. It'll give you the adjustability you need.

The 2.8 Cologne V6 used this huge carb with sucess. It allows you to jet the carb down a few call numbers, and still have it rich enough under wide open throttle.

If your ignition is done first with a 16 degree intial and all in at 32 degrees by 3000 rpm, the Autolite 2100 will like a lean condition under part throttle, and a richer condtion can be catered for by the power valve's second stage at wide open throttle.

I just so happen to have 3 MC2150s from Jeeps sitting in the garage. I got 'em for about $25 a piece so it was one of those hard to turn down situations. They are all 1.21, 351 cfm, so a little bigger than what I have on there right now. I was a little afraid of over-carb'ing my 200 with those though. But I might be able to steal the PV cover off of one those and use a 2 stage valve with the 1.14.

Of course, I could always just try one of the 2150s (just pick the cleanest looking one) and see what happens. if nothing else I could steal a PV from one to see if that helps out. Is there and easy inspection method for identifying a blown PV?

I think this PV is really the culprit given everyone's advice, coupled with this information:
> Idle set screw backed out all the way (this time no dashpot interference)
> Got idle down to 900 RPM (in neutral AT) by having 1 mix screw at 1.0-1.5 turn and seated the 2nd one
> Heavy black soot coating my garage floor and air compressor
> Engine stumbles if I drop RPM below 900 (too rich of a mixture?)

Howdy Again Bob:

While you're at it check the jet size in the 1.21s. They might surprise you with a pair of 47fs. Do you know that they are good running carbs?

Set both low speed idle screws at 1.5 turns out and adjust from there.

A 1.21 may be a little big for your cam but worth a try.

Adios, David

I'm off to test some hardfill, but while I've got breath in my lungs...http://vb.foureyedpride.com/showthread. ... ost1817575

On 83 to 1986 Mustang4bbl Mnauals and 4-bbl Truck 4190's and 4195's

xctasy":21snw18i said:

Always use the stock 4180c 2 stage power valves if they are clean and in good condition. Ford standard parts are hard to beat.


Most of the extra info is marketing spin, IMHO. No really logical, coherant issues on 1st Stage Restriction size. Power Valve Channel Restrictions on the 4180c are fine, and as long as the 2 stage power valve is in good shape and the right primary and secondary numbers, its all good. Just don't buy junk power valves.


Since using a non standard single stage Power Valve PV won't make you fail an IM test, Holley don't like selling replacement 2 stage power valves, so make it difficult to interchange them.

Here is there interchange.

Stock was a 10.5/5.5 Hg opening PV.

A 6.5 hg or 65 call size is the right interchange.

Other lists have other numbers


#125-208, #125-207, #125-206.

from http://www.fordification.com/forum/viewtopic.php?t=47498

Click to expand...

Use a stock 5.0 M code manual power valve any time you come up with a 6.5 to 7.5 power valve slection, and you can jet down the main jets a couple of call sizs.


Or the second schedule M code list above.

Repeated here. Fords later CE 126, 130 and 132 are pretty much exact 4180C 1st stage 10.5 and Second Stage 5.5 interchanges

Thanks again for the data. I think I'm going to have to start a database for all this!

Good idea on scavenging the jets. 2 of the 3 2150s look like they're "running". Maybe in need of a gasket kit. The third is pretty dirty and will need a little more TLC.

I bought a Harbor Freight ultrasonic jewelry cleaner a couple years back that I used to clean the Holley 1940 that was originally on the car. That did a pretty good job. Actually worked better than the dip. I used a mix of water and vinegar. Next time I'll just use straight vinegar. Beauty part is I don't have harsh chemicals to dispose of at the end.

I'm back on night duty tommorow night so I have a little free time.

No need to data base, just bookmark the Falcon Six Performance book, and list this as relevent detail.

There are still about 23 different 2 stage power valves in common production, including one fully adjustable 2 stage from Mikes carbs.

Holley set a truck like 14 pounds per cube limit before you really needed to consider a 2 stage power valve. It was based on the idea that frontal area would also go up from about 20 sq feet in a little Falcon or Mustang II to about 40 sq feet in an E 250 truck. Low power to weight vehicles benefit from being able to lean off the richness in slow, ambling load conditions. So two stage carbs were birthed in the economy verses emissions era, and the 14 pound per cube idea played out like this...

6440 pound shipping weight 460
6006 pound shipping weight 429
5600 pound shipping weight 400
5180 pound shipping weight 370
4900 pound shipping weight 351
4220 pound shipping weight 302
3570 pound shipping weight 255

But the lighter 1983 to 1985 5.0 Mustangs, Capris and 1981 to 1988 5.8 F150 and Bronco trucks were 10 pound per cubes on some versions, and gained exceptional verve and fair economy with a 2 stage power valve 4180 or 4190/4195 Holley carb. So did the 2-bbl 2150 1.21 carb in the 1982 5.0 Mustang GT, and the odd 2150 equiped 400 Bronco or F150's. Jet sizes in big 2150 carbs were squeezed right down to F56 in 2-bbls and H62's in 4180C 4-bbls.


Even below 14 pounds per cubic inch recomendations Holley set, FoMoCo found the 2 stage power valves allowed base jetting to be leaned, and the large V8 style Power Valve channel restrictions left to enrichen 8 jet call sizes.

14 pounds per cube is a 170 2380 pound Round Body Falcon,
a 200 cube a 2800 pound Fox body Zephyr, Fairmont, Capri or Mustang,
a 250 cube 1968-1973 Fairlane, Ranchero or Torino, or 75-80 Granada/Monarch.

A 79 or 82 5.0 Mustang can have as little as just 9 pounds per cube to lug around, and gets better economy and drivabiliy with the two stage power valve; they kept it rght up untill the last carbed 5.0 V8 in 1985. The two stage PV is just an added bit of extra tuning to the whole kit. Ford found the 255 engine saved 1.5 mpg, but the 1982 5.0 gained 35% more power with a 1.5 mpg highway gain at 55 mph; no mileage penalty, and much of that was the igntion, power valve and gearing. So the anular booster 2150 and 4180 carbs with those valves were exceptionally distinquished economy engines, as well as being quite exceptional performers.

P/N, 1st Stage Opening, 2nd Stage Opening, and any known 1st stage restriction

Holley Lists 3 now, down from 7 a while ago, down from 21 a long time ago.
125-206 12.5” Hg 5.5” Hg .028”, like the old Holley PN 2-4311 (later 25BP-475A-12)
125-207 10.5” Hg 5.0” Hg .021” like the old Holley PN 2-4312 (later 25BP-475A-25)
125-208 10.5” Hg 5.5” Hg .028”
Others

125-213, 11.5, 5.0
125-212, 12.0, 6.5
125-215, 10.5, 6.0
125-218, 11.0, 5.5 (23 means a 125-218)

Holley had 21 total if you include the unlisted “24” we found lurking under the hood of an 83 Mustang 5.0 GLX



Examples:-There are date prefixes before the Holley 2 stage call number
A6-7 Stock AMC 304 Motorcraft 2100 1.08 model 5.5
8 '85 Capri/Mustang 5.0 Holley 4180C stamped "8", means the 2nd stage would come in at 4.5
B1 8 Ford 460 F250 4X4 with 4180c come in at 4.5
13 On some IH 2300C truck carbs come in at 6.5
16 carbs with this PV come in at 6.5
23 = 1984 Capri/Mustang 5.0 Holley 4180C F1 23, or 125-21811.0, 5.5, BUT SAYS come in at 6.5
24 = 83 Mustang 5.0 GLX 5.0 not on list
Standard rebuild Capri/Mustang 5.0 Holley 4180C 3-1346 kits = 10.5/6.5, no traditional stamping

MIKES Carburettor Parts Has 11or 12 generic Number:70-1000 2 Stage Power Valves




Napa offers a total of 8 diff. 2-stage power valves.

PN 2-4311 1st stage opens @ 9.0"Hg, 2nd stage @ 2.5"Hg 1st stage restriction .035

PN 2-4312 1st stage opens @ 10.5"Hg, 2nd stage @ 5.5"Hg 1st stage restr. .021

PN 2-4405 1st stage opens @ 9.0"Hg, 2nd stage @ 2.5" Hg 1st stage restr. .028

PN 2-4406 1st stage opens @ 10.5" Hg, 2nd stage @ 5.0"Hg 1st stage restr. .020

PN 2-4409 1st stage opens @ 11.0"Hg, 2nd stage @ 7.5"Hg 1st stage restr. .028

PN 2-4410 1st stage opens @ 10.5" Hg, 2nd stage @ 5.0"Hg 1st stage restr. .028

PN 2-4412 1st stage opens @ 11.0"Hg, 2nd stage @ 6.0"Hg 1st stage restr. .0225

PN 2-4413 1st stage opens @ 11.0"Hg, 2nd stage @ 7.0"Hg 1st stage restr. .024

Ford had five Motorcraft 2150 2 Stage Power valves from 1974 to 1979. Since it has a wide range of crack off vacuums, I've listed them as

CE105 Nominal 7.0”Hg/ 2.0”Hg
CE120 , CE123 & CE122 Nominal 7.0”Hg/ 2.0”Hg
CE126 Nominal 10.0”Hg/ 3.5”Hg
CE130 Nominal 10.25”Hg/ 5.0”Hg
CE132 Nominal 10.25”Hg/ 6.0”Hg

So only 1 of the 3 2150s had the larger PV. I pulled the jets out of that one this morning and they were both 57F. So at least the thing had matching jets! That's a plus I'll pull the PV this evening to see what it is. I'll also pull the PV on the other 2 to see what size they are. I don't know if it's worth my time to crack open the fuel bowls on the other units to look at the jets. Based on the information that xctasy provided, the 50F is right about what it should be for this particular setup.

WoW.
W/my limited understanding, experience and knowledge I C an analogy (may B just in MY mind).
It seems the above iterations extrapolate to the "chippers" when we get to efi, FI and the modern day? They had their history (change a chip for power, change for better economy, change for 'etc') with these offerings...

Once you replace the power valve unless you have an A/F tester you are just guessing. Follow my recommendations & you will be spot on.

I have a wideband sensor and guage but they are not installed yet. That was going to go in when the new exhaust got installed. I've been planning on that being the main method of fine tuning the carb. I'm running pretty rich right now and want to get things staged for when it's actually nice enough again to get the car out.

FYI, I sent you a PM about getting the distributor dialed in.

Pulled the carb today to replace the PV. I had a clean 6.5 so that's what I put in for now. It may run a little rich but I'll fix that later once I have the wideband set up. Some things I did notice:

> throttle plates were not closing all the way. Backing out what I think is the fast idle cam resolved that. But I'm going to go back over that. I think I need to lock open the choke to make sure I'm not messing something up there by moving that.

> tightened some loose screws

> existing PV was installed with 2 gaskets. Is this some kind of hack way of installing it to fix some issue?

> wasn't overly happy with how the new PV seated. Almost felt as if it was slipping like it was stripped. Will probably pull apart and inspect the theads in the carb body. Could just be paranoia.

> going to block the ported vac source from the carb and run manifold to the HEI. Just got it back from Bill and this is the proper setup for my configuration.

Might be able to fire it up here in a couple days. Still recovering from sinus surgery so I've been a little slow on some things around here lately.

"...surgery …"
speedy recovery !

Well, I think I found that vac leak that I was suspicious of. It seems to have come as a cracked baseplate on the carb.

So I got the newly curved distributor installed. I ordered up a carb from wsa11. Then I buttoned that old carb back up, installed it, and test fired the machine today. I figured that if I was going to backfire a carb because my distributor wasn't in right, I might as do it on the one that is busticated. I did backfire, so it wasn't a waste of time. I didn't install it off by 180* though. The timing was just severely retarded. I cranked it up a bit and tried again and she was happy as could be. I have it dialed in to 20* of advance and using manifold for my vac source. Now that I think about it, pretty sure I forgot to disconnect the vac source. I guess I get to go back out there and try again. Oh well. At least I know it's setup correctly, just needs adjusted.

Later this week I'll go ahead and get the new carb installed and then play the waiting game until the weather is cooperative enough to go for a little jaunt. At least I'll be able to get the idle set. I'm also installing a vacuum manifold. Going to use that to set up the distributor, my PCV, a vac gauge mounted in the engine bay, a vac line to run to a gauge in the cabin, and a spare port for later if need be.

This spring I'll go about fixing that other carb. Seems a shame since it's in otherwise awesome shape. I'll see if I can find someone around here to weld it, then I'll resurface it. I'm assuming I can use the old trick of fine grit paper taped to glass or marble countertop in order to true her back up.

Have a non urgent PM for you...