Carburetor Jet size Chart 2F - ANY? (1 Viewer)

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We are looking for a carburetor jet sizing chart if available for the FJ40 2F engine.
Found the one chart on SOR web site but it shows no non USA carburetors jet sizing.
The jets we have installed now are 1.32mm primary and 2.00mm secondary. We have the truck stationed at 2,500' elevation and work it up to a 5,000'- 6,000'-7,000' elevation.
Want to install jets that will be okay if possible for all round or close.
Thank you
 
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So there is no known chart or carburetor sizing information for the Toyota FJ40 2F or F engines?
Thanks guys.
 
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This chart is probably inside pin_head's head-somewhere

Seems like a FAQ effort--sort of like Coolerman's bolt sheet(which I look at all the time)
 
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I don't really know. I haven't kept track on which jets were used.
Jim C knows. He has rebuilt a bunch of Aisans.
My experience is mostly with Solex, Weber and Rochester carbs.
 
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Its properly no big deal just my brother and I thought after all the years the FJs have been around someone would've made a small chart for the altitudes changes, just for reference. I would not know what size jet to put in without a chart of some kind, heck we don't even know how many options there are in jet sizes for the Toyota. We go from 1,500' elevations to 7,000' and sometimes higher when hunting and the rig runs a bit rough around 4,500' on up.
Thank you
 
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I doubt that it is a carburetion problems. Engines don't mind running rich up until the point that the mixture cannot be ignited which you won't encounter at even 10,000 feet.
 
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You maybe right about that but if we do not stop and adjust the mixture it will get worst up around 7,000'. We are considered making a mixture adjustable cable this winter that runs from the inside of the cab to the modified mixture needle screw, just dial it in. We have a friend who is big time into Fords and racing off road and has a set up as such in his modified F250. It has a dead stop to avoid seating the needle and doing damage. Real simple and works.
Just got to think outside the box.

Just want to insert that the cable system that is used was meant for the idle speed on the carburetor(s) and was modified for his mixture. It only will turn almost 90 degrees if I remember so it receives very small amounts of adjustments. Pretty cool but it is also a very large engine. We like the idea so we do not have to get out of the truck (getting lazy). If you hunt in remote places as we do it's always MUDDY.

Thanks
 
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The SOR chart covers fairly well the US sizing. Maybe it doesn't cover the non USA sizes, but depending on which carb you have you should be able to get close. For the most part, the larger the venturi the larger the jet size. You can always put in a O2 sensor in your exhaust and try different jetting to get it correct for your vehicle.

AFAIK, Toyota jet sizes do not come in a large variety of options like you might find for Weber, Holley, etc. You basically have to choose from the sizes listed on SOR's website (at least in the US, and I don't know of any aftermarket companies making jets in a multitude of sizes for Aisans).

Why don't you pull your jets out and tell us what you have (and tell us what year carburetor you're running)? Then we can compare to the SOR list and see if it matches up with anything.

An idle adjustment screw knob will only adjust the idle adjustment screw, which doesn't have much effect above idle on the F series engines. If would be better to optimize your primary and secondary jet sizes. You might have to split the difference and run a little lean at lower elevations so you don't over-richen the engine at higher elevations. My experience is that the F series engines aren't THAT sensitive to elevation change - my 2F runs just about the same whether I'm at 4,000 feet or 13,000 feet.
 

Trollhole

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I always wanted to come up with a way to adjust jets. Wouldn't be that hard as they reside right behind the bowl plugs. Would just need to come up with a brass device that would span the bowl and have a long thin needle in it. With some viton seals. Would need to be a precision piece but I would think it could be done. Wonder how the float would be affected?
 

FJ40Jim

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The jet sizing is not uniform because there are different venturi diameters, air correction jets and boosters.
e.g. a 150 is too rich in a 81 carb body, too lean in a 79 and just right in a 76.
 
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I always wanted to come up with a way to adjust jets. Wouldn't be that hard as they reside right behind the bowl plugs. Would just need to come up with a brass device that would span the bowl and have a long thin needle in it. With some viton seals. Would need to be a precision piece but I would think it could be done. Wonder how the float would be affected?
You're talking about adjustable jet's right? So you don't have to take them out of the carb? There's a product called Adjust-a-jet. They only work with Holley however. There's a video on horespower about it, It's at 14:00 http://www.powerblocktv.com/episode/HP2009-09/ford-460-back-for-horsepower-hike
 

Trollhole

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You're talking about adjustable jet's right? So you don't have to take them out of the carb? There's a product called Adjust-a-jet. They only work with Holley however. There's a video on horespower about it, It's at 14:00 http://www.powerblocktv.com/episode/HP2009-09/ford-460-back-for-horsepower-hike


Yes. Just need someone to design and make one for our cruisers. I can see how it would be made but designing it in a cad model and making it possible is out of my league. Would be cool to be able to adjust your jets basically on the fly.
 

FJ40Jim

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Another way to trim mixture inflight is by changing the size of the air correction jet. IDK how to do that either, but the air circuit might be easier to modify than the fuel circuit (less fire hazard).
 

Howard705

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Speaking of in -flight -gasoline aircraft engine carbs are adjustable. I'd imagine carbs are a lot different. Any idea how this is done?
 

FJ40Jim

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Light aircraft have cable control of HAI and mixture. Main mix control is accomplished by managing the differential air pressure in the main circuit.
See post #16 for an idea of how to apply this to an automotive carb.
 

JohnnyC

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Stromberg and S.U. carbs have adjustable mixture .... however like most mechanical things british .... they are problematic... specially when dual carbs are used... S.U.'s once set correctly do run really well thruoght the rmp range IMHO


looks like double posts are the new standard on mud? :)
 
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About 1/4 way down this page: http://vintagespeed.com/ Looks to be an approach that would work. Would need some large OEM jets or drilled out jets to run the needle to.
I'd like to modify the secondary vacuum passage to be adjustable myself. Some Holleys have that with a needle valve to change the speed/timing and duration of the secondary. The static opening seems small.
 

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