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I have an 83 Cherokee with a 77 AMC360. I know the engine was bored 30 and I think there is a performance cam in there too. All work done before I got her. Still has stock manifold with a Holley carb. I’ve run into fueling issues, idle won’t settle down and runs rough at start up then a high idle after warming up a little. Cleaned gunk off linkage already and I was going to swap out fuel filter and rebuild carb but since someone else worked on her before me I was wondering if I should just get a new Edelbrock carb and manifold but am now thinking maybe go efi? Or EGR or non EGR manifold? Looks like some of the emissions crap was deleted as there are a couple lines that are sealed off coming off the manifold but I’m just guessing. Will get some pics on here if needed. Any thoughts or advice appreciated. Hoping to get this all done myself but it’s kinda cold out to be out there fumbling around scratching my head.

Rebuild of the carb is quick and cheap. Go with a basic rebuild to stock specs/ settings for that model carb. Try to get everything runing as well as you can. Then if you decide to go efi it will be much easier to set your base line tune and see inprovements.

Check for vacuum leaks too. If someone messed with emissions stuff it's possible you have an open vacuum line.

Regarding Carb vs EFI. There is a lot of debate. A lot depends on how you will use the truck and if you make a lot of changes in elevation. For example, I live in Phoenix (2000 feet) and when I head off to Ouray I have to jet down my Holley Truck avenger.

Lot's of EFI options. From cheap 'do it yourself' junkyard builds to full multi port injection $$$$. Most folks go with some kind of throttle body system. A new truck avenger carb will be less expensive. An EFI will net you a bit better MPG if it is tuned correctly. EFI drivability, if tuned correctly, will also be better than a carb. Cold starts will be better as well. EFI is a more complicated installation. Typically includes a higher pressure fuel pump (electric), a return line for the fuel, the installation of a AFR in the exhaust system and some additional wiring. Some EFI systems will work with special distributors and will adjust timing as well.

I kept it simple. I have a holley truck avenger and love it. But I don't daily drive my rig. I go off road a lot so I like the simplicity. I live in Arizona so cold starts are not an issue.

Do you need the emission equipment on board? If not and since some of it has been removed, I think I would spend the time to remove all the emissions junk and cleanup the vacuum lines you don't need anymore. Then replace the remaining vacuum lines with new hoses. It is kind of amazing how well the AMC V8 runs when that crap is cleaned up and vacuum leaks fixed.

fulsizjeep wrote:Do you need the emission equipment on board? If not and since some of it has been removed, I think I would spend the time to remove all the emissions junk and cleanup the vacuum lines you don't need anymore. Then replace the remaining vacuum lines with new hoses. It is kind of amazing how well the AMC V8 runs when that crap is cleaned up and vacuum leaks fixed.

Well, let's be clear on 'emissions junk'.

The PCV is the first and most awesome emissions control system. No impact to performance. Great for the environment. Very simple. Look it up on Wikipedia. Fascinating. Even new cars use this system. It has the most impact on emissions. It's awesome.
EGR is also a very good emissions control system that has no impact to performance. Also very simple. I think this is no longer needed on new cars.
The A.I.R. pump has some benefit but is very complicated. Very limited impact to performance. This is my least favorite system.
The evaporation systems provide benefit without any impact to performance. Its basic purpose is to make sure any gas vapors from the tank do not escape into the atmosphere and instead are included in the combustion process. Win Win. You don't see this on new cars because the system is more sealed.
There is another system that will adjust the air going into the air cleaner. When the engine is cold it diverts the input so the air is passed over the engine exhaust manifold. This helps 'warm' the engine up faster. An engine at normal operating temps is much more emissions friendly. No real cost to performance.

What gets weird is stuff that tries to adjust the timing based on engine temps. This is easy for new cars but in the old days they relied on vacuum operated systems that would try to adjust how much advance was applied. This can effect performance and its effectiveness, IMHO, is limited.

will e wrote:

fulsizjeep wrote:Do you need the emission equipment on board? If not and since some of it has been removed, I think I would spend the time to remove all the emissions junk and cleanup the vacuum lines you don't need anymore. Then replace the remaining vacuum lines with new hoses. It is kind of amazing how well the AMC V8 runs when that crap is cleaned up and vacuum leaks fixed.

Well, let's be clear on 'emissions junk'.

The PCV is the first and most awesome emissions control system. No impact to performance. Great for the environment. Very simple. Look it up on Wikipedia. Fascinating. Even new cars use this system. It has the most impact on emissions. It's awesome.
EGR is also a very good emissions control system that has no impact to performance. Also very simple. I think this is no longer needed on new cars.
The A.I.R. pump has some benefit but is very complicated. Very limited impact to performance. This is my least favorite system.
The evaporation systems provide benefit without any impact to performance. Its basic purpose is to make sure any gas vapors from the tank do not escape into the atmosphere and instead are included in the combustion process. Win Win. You don't see this on new cars because the system is more sealed.
There is another system that will adjust the air going into the air cleaner. When the engine is cold it diverts the input so the air is passed over the engine exhaust manifold. This helps 'warm' the engine up faster. An engine at normal operating temps is much more emissions friendly. No real cost to performance.

What gets weird is stuff that tries to adjust the timing based on engine temps. This is easy for new cars but in the old days they relied on vacuum operated systems that would try to adjust how much advance was applied. This can affect performance and its effectiveness, IMHO, is limited.

I am calling BS on everything but the PCV. LOL!

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fulsizjeep wrote:

will e wrote:

fulsizjeep wrote:Do you need the emission equipment on board? If not and since some of it has been removed, I think I would spend the time to remove all the emissions junk and cleanup the vacuum lines you don't need anymore. Then replace the remaining vacuum lines with new hoses. It is kind of amazing how well the AMC V8 runs when that crap is cleaned up and vacuum leaks fixed.

Well, let's be clear on 'emissions junk'.

The PCV is the first and most awesome emissions control system. No impact to performance. Great for the environment. Very simple. Look it up on Wikipedia. Fascinating. Even new cars use this system. It has the most impact on emissions. It's awesome.
EGR is also a very good emissions control system that has no impact to performance. Also very simple. I think this is no longer needed on new cars.
The A.I.R. pump has some benefit but is very complicated. Very limited impact to performance. This is my least favorite system.
The evaporation systems provide benefit without any impact to performance. Its basic purpose is to make sure any gas vapors from the tank do not escape into the atmosphere and instead are included in the combustion process. Win Win. You don't see this on new cars because the system is more sealed.
There is another system that will adjust the air going into the air cleaner. When the engine is cold it diverts the input so the air is passed over the engine exhaust manifold. This helps 'warm' the engine up faster. An engine at normal operating temps is much more emissions friendly. No real cost to performance.

What gets weird is stuff that tries to adjust the timing based on engine temps. This is easy for new cars but in the old days they relied on vacuum operated systems that would try to adjust how much advance was applied. This can affect performance and its effectiveness, IMHO, is limited.

I am calling BS on everything but the PCV. LOL!

Sent from my XT1032 using Tapatalk

hey, I thought you were a Colorado 'greenie'! (sent with love)

will e wrote:

fulsizjeep wrote:

will e wrote:
Well, let's be clear on 'emissions junk'.

The PCV is the first and most awesome emissions control system. No impact to performance. Great for the environment. Very simple. Look it up on Wikipedia. Fascinating. Even new cars use this system. It has the most impact on emissions. It's awesome.
EGR is also a very good emissions control system that has no impact to performance. Also very simple. I think this is no longer needed on new cars.
The A.I.R. pump has some benefit but is very complicated. Very limited impact to performance. This is my least favorite system.
The evaporation systems provide benefit without any impact to performance. Its basic purpose is to make sure any gas vapors from the tank do not escape into the atmosphere and instead are included in the combustion process. Win Win. You don't see this on new cars because the system is more sealed.
There is another system that will adjust the air going into the air cleaner. When the engine is cold it diverts the input so the air is passed over the engine exhaust manifold. This helps 'warm' the engine up faster. An engine at normal operating temps is much more emissions friendly. No real cost to performance.

What gets weird is stuff that tries to adjust the timing based on engine temps. This is easy for new cars but in the old days they relied on vacuum operated systems that would try to adjust how much advance was applied. This can affect performance and its effectiveness, IMHO, is limited.

I am calling BS on everything but the PCV. LOL!

Sent from my XT1032 using Tapatalk

hey, I thought you were a Colorado 'greenie'! (sent with love)

Burnin' Dino fuel till I die.

Sent from my XT1032 using Tapatalk

I'm more on will e's side.

Another excellent emission system is vapor recovery. Has zero impact on performance, negligible maintenance, and and vents your fuel without venting vapors to the air. This is good for the air, but also keeps your Jeep from stinking. Old cars stink of gas, especially when parked in a garage. You're also conserving valuable fuel that normally would be lost to the air. Instead it's captured and burned as fuel, as intended.

Catalytic convertors are also an excellent addition. Modern cats do not need the air injection, like the older ones do. An EFI system eliminates the need for air injection too, since it can keep the air-fuel ratio in the range where the cat is not flooded with unburned fuel. Air injection is a maintenance headache, though only a slight parasitic load.

EGR is a system that reduces the combustion temperature to lower the amount of nitrous oxides produced with combustion. It does compromise performance slightly, but NOx is nasty stuff.

Thermostatic air cleaner helps cold-weather performance at negligible cost - a few extra hoses under the hood. Also prevents carburetor icing under cold, wet conditions. However, much the need for it is driven by use of a carburetor (ie flap that closes when the engine is off).

The rest of the gear is mostly vacuum-driven servos that can be entirely replaced by electric servos under the control of a computer - that is, EFI. Much of the plumbing on these engines simply gains control over a relatively small number of downstream devices. Take a look at the instructions for the Howell CARB-compliant EFI. Very few systems and little plumbing is required to comply with California specs through 1993. It needs PCV (duh), vapor recovery (duh), catalytic convertor without air injection, and EGR. All the other stuff (and much of the detuning I presume) is required because of the archaic carburetor and vacuum-modulated control system.

My understand of the EGR system is that when it is functioning correctly it doesn't function during load and will not impact performance.

I clump vapor recovery into the evaporative system.

You may be right. At full throttle, there's no vacuum so the EGR is off. At part throttle you don't care about loss of volumetric efficiency. Hmm.

I just missed the evaporation part. Reading too fast...

No worries, many names for the same things.

We both agree that not all 'emissions' stuff is 'crap' that 'sucks away performance'. Yes, there is some overly complicated systems that provide very limited benefit and may be a candidate for deletion but folks shouldn't hate it all.