jetting a 2150
Thread Starter
|
Senior User
Joined: Apr 2003
Posts: 180
Likes: 0
From: NB, Canada
jetting a 2150
What jets would you recommend for a 1978 2150 with the variable metering rods and code 1.21. I got this carb recently to learn how rebuild with. It came out of an E-350 cube van, but it will probably go on a 351w in my truck. That will mean medium hauling and mstly secondary roads. I would lean toward fuel economy rather than extra power. Thank you.
Posting Guru
Joined: Aug 2000
Posts: 1,127
Likes: 3
From: (near) Denver USA
Need more info:
What year and model of vehicle?
Manual or automatic transmission?
CA or 49-state, or high-altitude emissions system?
Is the engine/drivetrain stock or modified? If modified, how?
At what altitude(s) will the truck operate?
What's the current carb on the 351W? Is it original?
What size jets are in the current carb?
How is the performance/economy with the current carb?
What year and model of vehicle?
Manual or automatic transmission?
CA or 49-state, or high-altitude emissions system?
Is the engine/drivetrain stock or modified? If modified, how?
At what altitude(s) will the truck operate?
What's the current carb on the 351W? Is it original?
What size jets are in the current carb?
How is the performance/economy with the current carb?
Thread Starter
|
Senior User
Joined: Apr 2003
Posts: 180
Likes: 0
From: NB, Canada
The truck is an 88 with a 351w changed to carb. Engine is stock other than the 78 intake and front cover to run the fuel pump. It has a C6 transmission. The emissions are not a problem, though I have to run the factory, second convertor along with the 24" glasspak; all exhaust is 2.5" pipe. Altitude is 150' above sea level. The current carb is a 75 2150 that works ok, maybe abit rich. I don't know what it was from or its jetting as I didn't want to tamper with it while it was working. It has a crack near one of the holdown nuts that reaches toward the float bowl that I fear will start leaking. The truck is running well with good power, with mileage in the 8-10 mpg range. I have changed the timing curve to give me total advance at 2500 rpm to combat some late burning fuel that I could hear when the exhaust valves opened. This is a points ignition that I may shift to a Pertronix Ignitor in time, although it is working well right now. I hope this is helpful in making a recommendation. If there is anything else you need I'll try to find the answers. The ID tags are gone from both carbs. I would like to be able to learn to do a rebuild. Thank you.
Posting Guru
Joined: Aug 2000
Posts: 1,127
Likes: 3
From: (near) Denver USA
Find out what jets are in the carb on your engine now. If it's too rich, go down by two numbered sizes (e.g., from 58 to 56) and try that. If it's still too rich, drop another two sizes.
It might be worthwhile to get your truck on a gas analyzer to verify the mixture. If you assume it's too rich and you start making adjustrments for that, when the problem is actually an overlean mixture, you'll spend a lot more money and time to fix it.
Remember, overlean mixtures cause lean misfire, which dumps raw fuel into the exhaust and smells about the same as an overrich mixture.
It might be worthwhile to get your truck on a gas analyzer to verify the mixture. If you assume it's too rich and you start making adjustrments for that, when the problem is actually an overlean mixture, you'll spend a lot more money and time to fix it.
Remember, overlean mixtures cause lean misfire, which dumps raw fuel into the exhaust and smells about the same as an overrich mixture.
Thread
Thread Starter
Forum
Replies
Last Post
whisler
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
1
Nov 4, 2014 10:38 AM
Hank, in or
1973 - 1979 F-100 & Larger F-Series Trucks
11
Dec 14, 2008 04:43 PM
Skyman
Fuel Injection, Carburetion & Fuel System
2
Oct 5, 2004 08:44 AM
