Carburetor and Exhaust manifold HELP

[84ChevySuburban]

Hi all, i want to put aftermarket headers on my 1984 K20 suburban with a 350. The issue i am having is all of the emission stuff attached to the manifolds. Another issue that I am having is with the carburetor. I wanted to replace the bulky ugly stock air filter with a nice aftermarket air filter, the issue with that is all the emissions stuff that is plugged into that stock air filter, and that leads to the valve cover. I bought a new air filter and when i ran the engine with all the emissions stuff unplugged and with the air filter off (I know it sounds stupid, but i wasn't sure it was working anyways so i wanted to see the engines response to these changes) the carb wasn't opening when i would give it gas. I want to bypass all the emissions stuff so i can get a nice set of headers, and run the new air filter that i have. I also want to get rid of the clutter that the engine has. Any input would be much appreciated. I am fairly new to the Squarebody community and would like to know a lot about these trucks, and the do's and don'ts with owning them and tuning them.

,Andrew

 

[Honky Kong jr]

Welcome. What id do is rip all that crap off. Sort threw the engine harness find only what you need. Starter, 12v source for the cab, alternator, ignition (distributor) and your gauge sender wires. And a older style HEI distributor. But that me. There's a few other in that harness you will need but the will be obvious, as they will be plugged into non-engine stuff. And if that carb has more the 1 wire on it, it would be gone too.

 

[84ChevySuburban]

Ya i was thinking cutting everything off thats not associated with the torque converter/clutch solenoid and the transmission control vacuum switch. As for the carburetor, your saying invest in a new setup if it has more than 1 wire on it?

 

[84ChevySuburban]

Thanks again for the help i really appreciate it

 

[Honky Kong jr]

Ya i was thinking cutting everything off thats not associated with the torque converter/clutch solenoid and the transmission control vacuum switch. As for the carburetor, your saying invest in a new setup if it has more than 1 wire on it?

If it has all that throttle position crap and electronic mixture stuff I'm not 100% on them because I dump it and don't bother with it. @1987 GMC Jimmy knows his stuff on them carbs. If in fact it is an electrical carb.

 

[84ChevySuburban]

you think youd be able to identify it if i sent a couple pictures?

 

[1987 GMC Jimmy]

This here is an E4ME Quadrajet. Note the blue Mixture Control Solenoid on top and the three wire TPS connector on the side.

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I wouldn't discount having this one since you're so close to California, but from what I heard, it sounds like you have an M4MC/M4ME Quadrajet, which is the non-feedback type with either divorced or electronic choke. The electronic choke will have a wire plugging into on the passenger side.

If you have the electronic Quadrajet, your options are to ditch it or keep it, basically. You'd notice the presence of a SES light in the cluster and an OBD I data link connector by your shins on the driver side. The system works, the only caveat to it is if the carb was touched by a complete tool or if the engine harness was hacked. The support's pretty limited on them, but I do know my way around the CCC system okay if you get to this point. Thanks @Honky Kong jr, by the way. If you have a run of the mill Quadrajet, I'd keep it for sure. A good rebuild, seal the well plugs, and primary throttle bushing to fix the vacuum leak on a tired carb, and you're good to go.

As far as the emissions stuff goes, I'm guessing you're not in Maricopa, Pima, Yavapai, or Pinal Counties. If not, I'd get rid of a lot of that trash but not all of it if it were me. The PCV system and the Evaporative Emissions system are a must. The PCV valve will help keep sludge out of your motor, and the evaporative emissions keeps your vehicle from smelling like a gas station. The evap delete is a kind of a study in half assery, anyways, so it's better to just leave it on in my opinion. The EGR is debatable. I think the power it robs, while quantifiable, is fairly negligible, and it does help keep combustion temps down. I'd definitely say goodnight to the rest of that mess, though.

 

[84ChevySuburban]

This here is an E4ME Quadrajet. Note the blue Mixture Control Solenoid on top and the three wire TPS connector on the side.

You must be registered for see images attach

I wouldn't discount having this one since you're so close to California, but from what I heard, it sounds like you have an M4MC/M4ME Quadrajet, which is the non-feedback type with either divorced or electronic choke. The electronic choke will have a wire plugging into on the passenger side.

If you have the electronic Quadrajet, your options are to ditch it or keep it, basically. You'd notice the presence of a SES light in the cluster and an OBD I data link connector by your shins on the driver side. The system works, the only caveat to it is if the carb was touched by a complete tool or if the engine harness was hacked. The support's pretty limited on them, but I do know my way around the CCC system okay if you get to this point. Thanks @Honky Kong jr, by the way. If you have a run of the mill Quadrajet, I'd keep it for sure. A good rebuild, seal the well plugs, and primary throttle bushing to fix the vacuum leak on a tired carb, and you're good to go.

As far as the emissions stuff goes, I'm guessing you're not in Maricopa, Pima, Yavapai, or Pinal Counties. If not, I'd get rid of a lot of that trash but not all of it if it were me. The PCV system and the Evaporative Emissions system are a must. The PCV valve will help keep sludge out of your motor, and the evaporative emissions keeps your vehicle from smelling like a gas station. The evap delete is a kind of a study in half assery, anyways, so it's better to just leave it on in my opinion. The EGR is debatable. I think the power it robs, while quantifiable, is fairly negligible, and it does help keep combustion temps down. I'd definitely say goodnight to the rest of that mess, though.

Thanks for the help! I do not have any of those wires attached to the carb, this suburban was government owned by the school i go to so none of it had been messed with, it was bone stock when i bought it. It only has 52,*** miles on it. It just looks rough because it was a work truck, I bought it to slowly get it back to good condition, plus it makes a stellar offroad truck. This truck drinks fuel and i heard that some of the emissions stuff, if it is not working in proper order can really mess with economy. I have the th350, which i cant say im a huge fan of, and it drinks fuel on the highway.

 

[MikeB]

Yes, definitely post pictures of the carb.

The factory service manual for my 82 C10 has an entire section on emission controls, and each of the systems is described fairly well. I'd suggest you find an 84 Suburban manual. You may even find reprints posted on the Internet. That way, at least you know what you're disconnecting and what it affects -- ignition advance, EGR operation, evaporation canister purge, etc.

As for the air cleaner, does it have a 4" hose running to the radiator support? If so it's probably more efficient that an open element air cleaner that sucks in hot air blown into it by the radiator fan! But do make sure the air valve opens completely when the engine warms up.

My 350 has no emission controls except PCV, but I did buck the trend and used a 60s or 70-something air cleaner and aftermarket hose to get fresh air into the engine. Probably not the best solution for high RPM, but this engine spends most of its time in the 1500-4000 RPM range.

You must be registered for see images

 

[highdesertrange]

OMG don't y'all know if you remove the smog equipment you are going to kill polar bears. just kidding. if you are in an area without smog inspections pull all that crap off. highdesertranger

 

[Tobe's84Jimmy]

i'm on HonkyKongJr's band wagon on this one. if youre gonna mod, then mod, as long as you dont have to do emissions anymore. modding is never perfect, and honestly a non-modded drivetrain has WAY better street manners than a modded one ( daily drivability without constant adjustment while dialing in ). but the bottom line is i cant leave nothin alone, modify all you can and enjoy your experiment. advice: keep anything you take off for at least a month after you think you dont need it.

 

[MikeB]

Advice: keep anything you take off for at least a month after you think you dont need it.

That's very good advice, but I'd keep some things longer than that. Over the years I've given away, thrown away, or sold all kind of parts from a 69 pickup, 55 Chevy, and my 82 pickup that, many years later, I wish I would have kept. Some examples are clutch pedal & linkage, wheels, steering wheels, instruments, exhaust manifolds, and air cleaners.

 

[74 Shortbed]

I've kept **** for 20yrs, finally get rid of it and a month later I need it.............