good idle, no acceleration
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From: Northeast, OK
The jets are marked with something like "51F", which is probably about the right jet for your engine. See this thread: https://www.ford-trucks.com/forums/1...l#post16327595.
And the power valve is supposed to have a number on it like "6" or "8", but not all do. As you will see in the above thread, the power valve in the calibration code I discussed is a CE-132, which is a 2-stage PV that gives a bit more fuel between 9 and 11.5", about where you need it, and opens fully at 4.5 to 7.5" for full power.
And the power valve is supposed to have a number on it like "6" or "8", but not all do. As you will see in the above thread, the power valve in the calibration code I discussed is a CE-132, which is a 2-stage PV that gives a bit more fuel between 9 and 11.5", about where you need it, and opens fully at 4.5 to 7.5" for full power.
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Thanks Gary!
I'll get it pulled apart and see exactly what I have and go from there.
Just curious, if I set the choke plate so that is stays mostly closed, would this allow it to run more rich and theoretically improve the condition? The reason I ask is that when I bought the truck the choke was disconnected and the plates remained closed (like when choked) and it accelerated better. I won't say that it "ran" better but the stall/bog was not there until I got the choke working with the hot air stove and dielectric spring.
I'll get it pulled apart and see exactly what I have and go from there.
Just curious, if I set the choke plate so that is stays mostly closed, would this allow it to run more rich and theoretically improve the condition? The reason I ask is that when I bought the truck the choke was disconnected and the plates remained closed (like when choked) and it accelerated better. I won't say that it "ran" better but the stall/bog was not there until I got the choke working with the hot air stove and dielectric spring.
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From: Angier, NC
If you get fed up with the carb you have now and don't want to swap the intake to a v4 with new carb you can buy a Holley 2300 v2 that will bolt on to the stock v2 intake.
The 2300 comes as a 350 cfm and a 500 cfm I would go with the 500 cfm on that 302.
I have a 500 cfm on a AMC 304 to replace the MC 2100 and it was like installing a new bigger motor.
What is nice of the 2300 is it is half a Holley v4 so all the v4 parts work on the 2300 v2 for dialing it in.
http://www.jegs.com/i/Holley/510/0-4...FUM8gQodTlcPww
They do come with elect. choke above was the first I came to thru Google
Dave ----
The 2300 comes as a 350 cfm and a 500 cfm I would go with the 500 cfm on that 302.
I have a 500 cfm on a AMC 304 to replace the MC 2100 and it was like installing a new bigger motor.
What is nice of the 2300 is it is half a Holley v4 so all the v4 parts work on the 2300 v2 for dialing it in.
http://www.jegs.com/i/Holley/510/0-4...FUM8gQodTlcPww
They do come with elect. choke above was the first I came to thru Google
Dave ----
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From: Northeast, OK
If you do consider a bigger 2bbl, you may be tempted to compare 2bbl to 4bbl carbs. As explained here (THE CARBURETOR SHOP / Carburetor sizes and CFM), 1 bbl and 2bbl carbs are rated at a different amount of vacuum than a 4bbl. That link says:
To convert from one system to another (with a very small percentage of error) is relatively simple. Simply use the square root of 2 (1.414). Thus to convert a two-barrel rating into a four-barrel rating, divide the two-barrel rating by 1.414. To convert the four-barrel rating to a two-barrel rating, multiply the four-barrel rating by 1.414.
Using that math a 500 CFM 2bbl actually flows 354 CFM if tested like a 4bbl.
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From: Angier, NC
If you do consider a bigger 2bbl, you may be tempted to compare 2bbl to 4bbl carbs. As explained here (THE CARBURETOR SHOP / Carburetor sizes and CFM), 1 bbl and 2bbl carbs are rated at a different amount of vacuum than a 4bbl. That link says:
To convert from one system to another (with a very small percentage of error) is relatively simple. Simply use the square root of 2 (1.414). Thus to convert a two-barrel rating into a four-barrel rating, divide the two-barrel rating by 1.414. To convert the four-barrel rating to a two-barrel rating, multiply the four-barrel rating by 1.414.
Using that math a 500 CFM 2bbl actually flows 354 CFM if tested like a 4bbl.Again I did a v2 500 cfm swap for a MC 2100 on a 304AMC and with a little tuning runs great. It was a bolt on to the stock v2 manifold even was able to use the stock air filter assy.
Dave ----
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Thanks guys!
I got the remanufactured Motorcraft 2150 that I have pulled apart and the main jets are stamped '485'. I cannot find reference to that anywhere on the internet as far as what size jets they are. I assumed I would find a two digit number...any ideas?
On a related note, I just picked up an '89 351W as a side project. It has a Holley 2300 2bbl on it. Any chance the jets are interchangeable between the two?
I got the remanufactured Motorcraft 2150 that I have pulled apart and the main jets are stamped '485'. I cannot find reference to that anywhere on the internet as far as what size jets they are. I assumed I would find a two digit number...any ideas?
On a related note, I just picked up an '89 351W as a side project. It has a Holley 2300 2bbl on it. Any chance the jets are interchangeable between the two?
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From: Northeast, OK
The jets may be interchangeable, but why not just bolt the 2300 on and see how it performs?
As for the jets, I've not heard of a 485. Is there any chance the "5" is an "F"?
As for the jets, I've not heard of a 485. Is there any chance the "5" is an "F"?
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I guess I could throw the 2300 on there...assuming nothing is wrong with it other than being filthy from sitting for years. I'd rather not throw more potential problems at it,but that may be the ticket. I looked at the jet numbers from 10 different angles, 10 different times and couldnt get anything but '485' out of it. I'll look again.
Assuming it was a 48F what would you recommend I change them to, given the previously discussed issues around the power valve, etc...? I've driven it a little more with the vac gauge in the cab and it looks like I get massive hesitation (lean) unless the vac drops to 6-8"
Assuming it was a 48F what would you recommend I change them to, given the previously discussed issues around the power valve, etc...? I've driven it a little more with the vac gauge in the cab and it looks like I get massive hesitation (lean) unless the vac drops to 6-8"
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From: Northeast, OK
Looks like you are really jetted lean, and your power valve fixes that when it opens at around 7" of vacuum.
I just found something that says the 3-digit jets are "close limit" jets, and you read them by placing a decimal point between the last two numbers. So, you have a 48.5. Given that, I'd go with 50's.
I just found something that says the 3-digit jets are "close limit" jets, and you read them by placing a decimal point between the last two numbers. So, you have a 48.5. Given that, I'd go with 50's.
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Looks like you are really jetted lean, and your power valve fixes that when it opens at around 7" of vacuum.
I just found something that says the 3-digit jets are "close limit" jets, and you read them by placing a decimal point between the last two numbers. So, you have a 48.5. Given that, I'd go with 50's.
I just found something that says the 3-digit jets are "close limit" jets, and you read them by placing a decimal point between the last two numbers. So, you have a 48.5. Given that, I'd go with 50's.
So, a 50 would richen it up enough? Should I order 50's and 52's to be safe?
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From: Northeast, OK
That should work. The 50's should give you a 6% richer mix and the 52's a 15% richer mix. The latter is quite an increase, so you might want to get 51's, which would be 11% richer than your 48.5's.
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Awesome. Thanks Gary, you're the man. Of course, we've already established that.
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ordered size 51 jets, popped them in and...problem solved! I also ordered a 9.5" power valve but haven't tried it yet. Thanks again for all of them help with this!