Engine Compartment Questions
Thread Starter
Intermediate
Joined: Mar 2005
Posts: 26
Likes: 0
From: State College Pennsylvania
Engine Compartment Questions
I've decided to get my 81 painted, but before i do that i want to fix up the engine compartment so the whole car looks nice. This isnt something i have a lot of experience with, so bare with me. With my dad's help, i pulled the engine and most of the accessories from the engine compartment and i'm ready to start cleaning it up a bit. My goal is to make it look less cluttered and a little newer. I've decided to remove the A/C pump and condensor, air intake snorkels, and i'm looking to minimize even more. The main problem i'm having is seeing the year of my car, there is a ton of emissions crap that really clutters up everything. I was wondering if anyone with a similar year knows what i can and can't get rid of without messing up the computer/carb/etc. Also, i would really like to get rid of the air pump and try to replace it with something smaller if the only vacuum i really need is for the headlights. Finally, what are some upgrades i can make while i have everything out that will improve performance and will function with the stock setup, although im not looking to have some street demon, just to to feel a little more power and maybe have a deeper rumble. (headers, intake manifold, etc). Thanks a lot, and i appreciate any tips i can get.
Melting Slicks
Joined: Apr 2004
Posts: 2,083
Likes: 2
From: Montreal Qc.
If you have to pass emissions inspection where you live, you may have to keep everything. If not, you can ditch a lot of stuff.
The air pump doesn't do anything for vacuum, it (mostly) pumps air into the exhaust manifold, a primitive way of cleaning up the exhaust (it does more than that too, but I don't know off hand). If you remove it you need new exhaust manifolds (headers like you said). Your car has EGR and other temperature-controlled vacuum stuff, the bundle of hoses on the front of the intake. If you decide to change to a new intake all that stuff can go. 1981 has computer controlled Q-jet, some guys have removed that and put on a normal carb, there are other issues though, the computer also controls the distributor (I believe) and is linked to the trans. It is a multi-step process to remove all that, someone with an 81 who has done it will answer better than me, I just know second-hand there is more involved than just removing hoses and plugging vacuum ports.
Even without all that stuff, you use vacuum for:
Lights, power brakes, timing advance, HVAC controls, trans kickdown, vapor-canister, PCV, cruise control, etc. You will never get rid of all those hoses.....
or, like Empathos said, trash it all and drop in a crate!
The air pump doesn't do anything for vacuum, it (mostly) pumps air into the exhaust manifold, a primitive way of cleaning up the exhaust (it does more than that too, but I don't know off hand). If you remove it you need new exhaust manifolds (headers like you said). Your car has EGR and other temperature-controlled vacuum stuff, the bundle of hoses on the front of the intake. If you decide to change to a new intake all that stuff can go. 1981 has computer controlled Q-jet, some guys have removed that and put on a normal carb, there are other issues though, the computer also controls the distributor (I believe) and is linked to the trans. It is a multi-step process to remove all that, someone with an 81 who has done it will answer better than me, I just know second-hand there is more involved than just removing hoses and plugging vacuum ports.
Even without all that stuff, you use vacuum for:
Lights, power brakes, timing advance, HVAC controls, trans kickdown, vapor-canister, PCV, cruise control, etc. You will never get rid of all those hoses.....
or, like Empathos said, trash it all and drop in a crate!
Le Mans Master
Joined: Jan 2004
Posts: 8,295
Likes: 30
From: one night in Bangkok you are never lonely
A clean freshly painted engine and compartment looks great but to change too much could cost you $$$ also to remove the A/C completely may be a big mistake if you ever want to sell the car. I would clean and paint out things add new hoses and leave it like that. Plus as mentioned above your state may require you don’t remove things. 
Thread Starter
Intermediate
Joined: Mar 2005
Posts: 26
Likes: 0
From: State College Pennsylvania
Alright, thanks for the info. I am emmissions exempt in my state, so that shouldnt be a problem. Id love to just drop in a new powerplant, but with college and all the funds arent quite there. 
Team Owner
Joined: Jun 2004
Posts: 20,216
Likes: 4
From: Smile, it's just the internet.
New Distributor(maybe), New intake, New Carburetor, and a few pipe plugs. Oh, and gaskets, of course.
That's all you need to remove ALL the emissions crap from your car. If you want to spend a bit more, you can put on headers. If you ask around, you can find lots of guys willing to sell old parts that would fit the bill nicely. You should be able to find everything you need in the range of $350... Sounds like your dad might be able to help.
The sound of the car won't be influenced by headers, but they will help wring a little more power from the higher RPM range. Dynomax Super Turbo mufflers are very popular and very inexpensive and will make the car sound more muscular. Make sure you tear out the cat and 2-1-2 and put a true dual exhaust under there if you can swing it. Those old cats and 2-1-2 exhausts were awfully restrictive.
The vacuum for the headlights comes directly off the intake manifold.
I'm not at all familiar with the engine management in the newer C3s, so others will have to chime in and correct any assumptions I made.
That's all you need to remove ALL the emissions crap from your car. If you want to spend a bit more, you can put on headers. If you ask around, you can find lots of guys willing to sell old parts that would fit the bill nicely. You should be able to find everything you need in the range of $350... Sounds like your dad might be able to help.
The sound of the car won't be influenced by headers, but they will help wring a little more power from the higher RPM range. Dynomax Super Turbo mufflers are very popular and very inexpensive and will make the car sound more muscular. Make sure you tear out the cat and 2-1-2 and put a true dual exhaust under there if you can swing it. Those old cats and 2-1-2 exhausts were awfully restrictive.
The vacuum for the headlights comes directly off the intake manifold.
I'm not at all familiar with the engine management in the newer C3s, so others will have to chime in and correct any assumptions I made.
Burning Brakes
Joined: Nov 2004
Posts: 1,193
Likes: 176
From: Hillsborough NC
Consider leaving the air snorkels in place. Using an open air filter will cause your engine to draw in hot air. The factory snorkels are a cold air system and do a pretty good job. Additionally, if you do remove the snorkel, you will affect how the radiator seals to the hood, which will allow air to flow over the radiator instead of forcing it through it, potentially making you run hotter than you want.
Melting Slicks
Joined: May 2005
Posts: 2,152
Likes: 33
From: Folsom Ca
Originally Posted by SLVRSHRK
Consider leaving the air snorkels in place. Using an open air filter will cause your engine to draw in hot air. The factory snorkels are a cold air system and do a pretty good job. Additionally, if you do remove the snorkel, you will affect how the radiator seals to the hood, which will allow air to flow over the radiator instead of forcing it through it, potentially making you run hotter than you want.
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