Autolite 2100 and Holley 350 Carb Info Needed

[tri-power 250]

I am looking for a jet size comparison for a Holley to a Autolite carburetor. I am changing carbs from a Holley to an Autolite. I am hoping to get better driveable performance from the Autolite but might need to change the jets to get the right Air fuel ratio. I have a large number of Holley jets and realize that the Autolite jets are larger in physical size then the Holley jets. I will make an adapter for them to fit.
Thanks,
Ken

 

[xctasy]

Power valves discharges, jet call size for jet call size comparisons are not easy, and the response to the venturi signal and the many differences in the venturi sizes and types on 1100, 2100/2150's, make it a lottery to compare, but you'll get great results if you attack the calibration with some disipline.

They were the same thread as Holley jets till 1964, then changed to F stamped jets, with a different thread taper. With Autolites and Motorcrafts after 1964, the jet size is the call number.

So for 4100, 2100 and all the later Motorcraft branded Ford carbs, C5 codes or higher mean fat non Holley jets, with the call size the jet size.



If you get a 120-4- Blank blank jet, you could have a jewler reprofile the jet to Holley dimensions, or just order the Motorcraft versions. The choice is yours.

Some important background according to http://forums.vintage-mustang.com/vinta ... olite.html

Difference in size of thread is 0.0625 or 1/16-inch. Not enough "meat" for an adapter to exist.
The wall thickness of the theoretical part would be 1/32 thick.....BEFORE factoring
in the threading issues.That's one reason why you haven't seen any adapters.

On the good old Big Blocks, such as the 4-bbl earlier 4100's (pre 64, The long snout carbs) The Holley jets screw right in.

So its just the thread size and the call size differences. Flow rates are not comparitive for call sizes, but I have a rough conversion for you to use at your own peril.

Comparisons are here:-


The Weber Holley is different, and follows the post 64 Autolite/Motorcraft practice where diameter is the call size on early ones. Its metric, and uses Mircrons instead of Thou.Later ones were stamped for cc/min flow rate, but there is an interchange from the chart Rouge Spear posted.

http://i1215.photobucket.com/albums/cc5 ... etsize.gif.

You can rate Weber Holleys and Holleys as they have cc/min flow figures, but there are no figures on post 1964 F stamped Autolite/Motorcrafts.

I'd just use oriface size, and that will get a ballpark cc/min flow comparison.


I'll do a USE AT YOUR OWN PERILL Holley to Autolite/Motorcraft chart for you.


I guess the Autolite Motorcraft jet flow rates will be listed somewhere at Ford, but I haven't seen them published. From my estimates, I'd say the post 64 jets are much more systematic than Holley jets, as the call size is the oriface size, while Holleys call sizes aren't the same as the oriface diameter, they are chamfered in the factory to reach the book flow rates in Chart 3.


From viewtopic.php?f=5&t=8106

The Holley jetting listed here is found under that post.

Chart 3:
The jet sizes for Holley 2300/4150/4160/4165/4175/4500 carbs are:-


Red indicates the best estimate figures. HolleyWeber and Holley 2300/4150/4160/4165/41754180/4500 jets are not the same, and I've not seen all the data for all jets 40 to 59. Smaller jets have more headloss, and flow much worse than there area would suggest. Those from 60 to 100 are form the Barry Grant © 1997, catalogue
123 cc/min or 40 thou nominal, 40 call size jet
129 cc/min or 41 thou nominal, 41 call size jet
136 cc/min or 42 thou nominal, 42 call size jet
142 cc/min or 43 thou nominal, 43 call size jet
149 cc/min or 44 thou nominal, 44 call size jet
157 cc/min or 45 thou nominal, 45 call size jet
164 cc/min or 45 thou nominal, 46 call size jet
171 cc/min or 47 thou nominal, 47 call size jet
178 cc/min or 48 thou nominal, 48 call size jet
185 cc/min or 48 thou nominal, 49 call size jet
192 cc/min or 49 thou nominal, 50 call size jet
198 cc/min or 50 thou nominal, 51 call size jet
205 cc/min or 52 thou nominal, 52 call size jet
212 cc/min or 52 thou nominal, 53 call size jet
221 cc/min or 53 thou nominal, 54 call size jet
230 cc/min or 54 thou nominal, 55 call size jet
239 cc/min or 55 thou nominal, 56 call size jet
248 cc/min or 56 thou nominal, 57 call size jet
257 cc/min or 57 thou nominal, 58 call size jet
267 cc/min or 58 thou nominal, 59 call size jet
285 cc/min or 60 thou nominal, 60 call size jet
298 cc/min or 60 thou nominal, 61 call size jet
311 cc/min or 61 thou nominal, 62 call size jet
325 cc/min or 62 thou nominal, 63 call size jet
341 cc/min or 64 thou nominal, 64 call size jet
357 cc/min or 65 thou nominal, 65 call size jet
374 cc/min or 66 thou nominal, 66 call size jet
392 cc/min or 68 thou nominal, 67 call size jet
411 cc/min or 69 thou nominal, 68 call size jet
429 cc/min or 70 thou nominal, 69 call size jet
448 cc/min or 73 thou nominal, 70 call size jet
470 cc/min or 76 thou nominal, 71 call size jet
492 cc/min or 79 thou nominal, 72 call size jet
517 cc/min or 79 thou nominal, 73 call size jet
542 cc/min or 81 thou nominal, 74 call size jet
566 cc/min or 82 thou nominal, 75 call size jet
587 cc/min or 84 thou nominal, 76 call size jet
615 cc/min or 86 thou nominal, 77 call size jet
645 cc/min or 89 thou nominal, 78 call size jet
677 cc/min or 91 thou nominal, 79 call size jet
703 cc/min or 93 thou nominal, 80 call size jet
731 cc/min or 93 thou nominal, 81 call size jet
765 cc/min or 93 thou nominal, 82 call size jet
795 cc/min or 94 thou nominal, 83 call size jet
824 cc/min or 99 thou nominal, 84 call size jet
858 cc/min or 100 thou nominal, 85 call size jet
890 cc/min or 101 thou nominal, 86 call size jet
923 cc/min or 103 thou nominal, 87 call size jet
952 cc/min or 104 thou nominal, 88 call size jet
987 cc/min or 104 thou nominal, 89 call size jet
1014 cc/min or 104 thou nominal, 90 call size jet
1080 cc/min or 105 thou nominal, 91 call size jet
1150 cc/min or 105 thou nominal, 92 call size jet
1200 cc/min or 105 thou nominal, 93 call size jet
1260 cc/min or 108 thou nominal, 94 call size jet
1320 cc/min or 118 thou nominal, 95 call size jet
1375 cc/min or 118 thou nominal, 96 call size jet
1440 cc/min or 125 thou nominal, 97 call size jet
1500 cc/min or 125 thou nominal, 98 call size jet
1570 cc/min or 125 thou nominal, 99 call size jet
1640 cc/min or 128 thou nominal, 100 call size jet

 

[xctasy]

Looking at 2150 2-bbl Motorcraft carbs I found 351M 2-bbl's ran 53 thou jets on the 1978 cars, and they gave 164 hp sae net on some variants. I found the 1982 5.0GT Mustangs got 58 jets for 157 hp. And one guy, Bubba 250, got his 369 cfm 2-bl fitted out with 63 jets. All these may be different line sizes to Holley, but they look much smaller than what I've calculated for Holleys.

And now the chart

Data management rules are that item A must map to Item B, but because Holley jets list or call size isn't always the jet diameter, the relationships between each jet in the 61 and 71, 72, 73 don't exhist, they are invalid. Holley chamfers the jets to create flow on those, so I've just assumed cc/min is the same for the same orifcse size. Time will tell if that's right.

 

[turbo2256b]

Each holly jet size is aprox 4.5% change in flow. My best economy figures with multiple engine builds has been with Holley carbs. Have to fully understand how to modify all the circuits. Figuring differance of jet flows from one brand to another could be a bit tough as fixed metering orfaces could be quite a bit different.

 

[xctasy]

I agree, the above chart is a ropey correlation, and as such, its not a great start point.

The flow rate is contolled as much by chamfer of the oriface, not just internal diameter.Often, when you redrill a jet, you loose flow per minute because you introduce a miss match between the factory smooth chamfer, and the existing oriface edge, the blend in between the oriface and the chamfered backcut. Surface texture has to be the same, and its very difficult to get perfection in its execution. Hence, the Holley 60, 61, 62, 71, 72 and 73 jets have irregular size orriface differences to get the correct flow rate with the standard chamfered backcut.

Close limit jets(1.5% different flow rates in each call number, for example, the 531, 532, 533 jets in a 53 call size on some emissions Holley carbs), are quality assured for flow, but they get the flow by selective testing, since its easier to pick up a jet and establish that it flows the specified flow rate than to blue print a jet in the first place, to get the required flow.

With Autolite/Motorcraft, you have to get better info, or it may be a shot in the dark, with a 53 jet possible flowing as much as any 54 jet when you consider production tollerances.

 

[turbo2256b]

The actual A/F ratio is also dependant on venturi sizes, air bleeds, emulsion tubes, etc.

 

[bmbm40]

All interesting information on this subject I have seen a lot of questions about. Maybe this should be in a sticky along with any other info on Autolite and Holley jets and resources for them. I think someone posted on here a place that sold Autolite jets. Could save some guys time.

 

[xctasy]

1. Carbs Unlimited

http://www.carburetion.com/ford2v.htm

F2J-(jet size) is listed under F2JETKit, which has Jet sizes 47-52 (6 Pairs 12 Jets) for 49.95.

For the blanks, 35 to 46 and 53 to 72, you'll have to look at the other Walker catalogue source from here, the listed 120-4- Blank blank jets and 38 to 72 call size jets.

2. Or http://www.carburetor-parts.com/Autolit ... /120-4.htm for 4.95 for any two jets from 40 to 78 call size

3. And that master list https://buy.walkerproducts.com/carburet ... nents.html

These are 5/16" on the threaded end, post 1964, 1965 model year (C5 code)1100, 1101,1250 BELFAST Models, 2100, 2150, 4100 series. Earlier 2100 and 4100's have the 1/4" threaded end. Key is the date code if the carb tag is still on it.

English Essex built V4 engines with the 1-bbl Ford carb were used for Sonnet, Saab and Ford Corsair Capri Consul's and the US import 1600 cc Kent engines, well into the mid 70's, so there are out of left field ways of getting other jet sizes, you just have to do a little skulkin' around

Heaps of fortune people.

 

[xctasy]

WerbyFord has an interchange on F stamped post 1965 jets for 2100's.

see viewtopic.php?f=1&t=58193&p=446594#p447365

a 43F jet is roughly a 47 Holley

54H jets pri and 62H jets sec. That is about like 50F and 58F jets by the way they flow