I have several mustangs with engines ranging from the I-6 (200) to a 351W-2V. I have been trying to locate the CFM flow spec's for Autolite carburators: 1100, 2100, 4100, etc... Does anyone know of a website that posts the CFM specs for these Autolite carburators? Thanks.
Here's a few: the .98 2 bbl was 190 cfm, 1.01 was 240 cfm, 1.02 was 245, 1.14 was 300 cfm. The 1.23 2 bbl was356 cfm, the 1.33 was 424 cfm. In the 4100 4 bbl the 1.08 was 480 cfm, the 1.12 was 600 cfm. All these ratings came from George Reid's Ford HP Performance interchange, so take em with a grain of salt.
Imagine if Pony Carburetors created a 4100 using the 1.23 venturi. Theoretically they could make a 712 cfm Autolite!.
I have to say that my 735 Ford spec Holley has exceeded my wildest expectations, so I wouldn't swap it out regardless, but it would be nice to have more flow in an Autolite. Talk about a sleeper carb!
It wouldn't be rated at double the 2 bbl rating under Holley's test method. The 500 cfm 2 bbl is exactly half a 750 DP. The 2 bbl's are tested at 3.0"hg drop. The 4's are at 1.5"hg drop.
Imagine if Pony Carburetors created a 4100 using the 1.23 venturi. Theoretically they could make a 712 cfm Autolite!.
I have to say that my 735 Ford spec Holley has exceeded my wildest expectations, so I wouldn't swap it out regardless, but it would be nice to have more flow in an Autolite. Talk about a sleeper carb!
it's funny you should mention that, i just got a reply to an email from pony carbs, asking when their "new" 4100 was supposed to be available and if there would be any performance versions in larger CFM ratings than the factory 4100's. they said they would be making larger than factory performance 4100's (they didn't specify how much larger, though), the largest factory 4100 had 1.19 venturis and is supposed to flow around 650-670 cfm, so a 1.23 would have to flow around 750 or more. of course a flow bench would be needed to really determine how much flow any of them have, i have read the 1.12 actually flows closer to 520 cfm than the always quoted 600 cfm too, btw, and even several 1.12 versions flowed deifferently from around 500 to 530 cfm, and the 1.08 actually flows closer to 440 cfm, it all depends on the individual booster clusters used in each carb.
i would love to find one of the super rare 1.19 venturi 4100 carbs and throw some goodies at it. i have an old article from the 70's on how to super-tune the 4100. it has lot's of good info like replacing the needle and seat assemblies with carter AFB pieces, using standard holley secondary springs to tune the secondary opening, etc. FYI 64 and earlier 4100's used standard holley jets and 65 and later version used the oddball ford jets.
It wouldn't be rated at double the 2 bbl rating under Holley's test method. The 500 cfm 2 bbl is exactly half a 750 DP. The 2 bbl's are tested at 3.0"hg drop. The 4's are at 1.5"hg drop.
roger that, but the numbers from George Reid's book list 300 cfm for a 2bbl with 1.14, and 600 for a 4 bbl with 1.12, so the Ford ratings look much more consistent between the 2 and 4 bbl carbs.
it's funny you should mention that, i just got a reply to an email from pony carbs, asking when their "new" 4100 was supposed to be available and if there would be any performance versions in larger CFM ratings than the factory 4100's. they said they would be making larger than factory performance 4100's
I sure hope they scan all the Ford blogs and are listening to their potential customers. Personally, I would rather be able to buy a brand new carb that Ford never made than some rare reproduction 1.19. I also don't want to invest the time it would take to try to find one on ebay.
i just really, really like the 4100 carbs. that's what was on my GT when i bought it in 1984. i love the fact that i can rebuild one in my sleep and how reliable and efficient they are. a new and improved repro in larger performance oriented sizes would the perfect carb to me.
on a slightly similar note Summit is now repro'ing the Holley improved version of the 4100, the holley 4010.
roger that, but the numbers from George Reid's book list 300 cfm for a 2bbl with 1.14, and 600 for a 4 bbl with 1.12, so the Ford ratings look much more consistent between the 2 and 4 bbl carbs.
I sure hope they scan all the Ford blogs and are listening to their potential customers. Personally, I would rather be able to buy a brand new carb that Ford never made than some rare reproduction 1.19. I also don't want to invest the time it would take to try to find one on ebay.
Neither Holley's nor Ford's ratings mean much in the end. Both are just ratings to compare one carb to another. The true test is what any one carb does on any one motor in actual application. For instance a 600 cfm Holley will flow a completely different cfm on a stock 289 from what it will flow on a built up 460. The center 250 cfm rated Holley 2 bbl on my 331 actually flows around 360 cfm at partial throttle, partial I mean at the point where the progressive linkage gets to the point to where it's engaging the other two 250's on the intake.