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3K views 12 replies 7 participants last post by  davesdeville 
#1 ·
hey guys,

Im starting work on the enigine of my 1976 cadillac deville, I figure if im going to get 14mpg with no power I may as well be getting 8mpg with *import Killing power*...

The first mod I want to do is removing the A/C pump and rad if posiblle. my only concernt is I live in canada and even tho I dont drive the car in winter there is many days I need defrost/heater while driving.

My question is can I remove the pump/rad/hosing and still have a fully functional heater/defrost? If so what do you do with the lines going through the firewall, can you take out the A/C posion on the inside of the cab too...?

Sorry if this is a stupid question, Im a N00b when it comes to this stuff

Thanks guys, keep it LLac-in
Lee Hern
 
#2 ·
Without the A/C, you will use the defogging advantages of the system. It can be helpful in cool weather when the windshielf fogs up.
But other than that, I've run several Cads in the winter with no A/C compressor, or dead A/C systems. The heater will work fine.
Just remember to replace the bolts that go into the intake. On the 425 they go into the intake and can cause a vacuum leak. I'm sure the 472 and 500's are the same.
As for the hoses, I'd remove them and block them off so dirt, bugs, etc don't get in there incase you ever want to restore the A/C system.
 
#3 ·
Your questions are not stupid.

Yes, you can remove the a/c compressor and condenser coil. Your defrost will still work just fine, although it works better with the a/c system.
I would suggest that you plug all disconnected a/c hoses to prevent dirt from entering the system. Who knows, you or a future buyer may want a/c again. Save all parts. I do not recommend removing the evaporator coil and housing. If you do you will need to find a replacement housing from a non-a/c car for proper air flow.

I assume that you are planning to change the intake manifold (the usual reason for removing the compressor).
 
#4 ·
yes I want to put a edelbrock intake on there asap... so one the pump is removed can I just find a shorter belt so I can still have power steering? will a belt clear if I run it right over from the crank to the power steering pump...? wow that sounds confusing even to me lol.

my plans for the future are removal of A/C, cam, intake monifold, then Electric cut out exhaust... for those of you who dont know thats a section of pipe you weld in your ehxuast that splits into two pipes, one pipe goes to our muffler and cat. (if you have one) the second goes directly out the side. theres a electric "switch" that alows you to open the strait pipe portion at will.

so heres how it works, you out with your buddies crusining around saturday night in your huge boat listning to some classic county and western....(or atleast thats what the 16 year olds in Airdrie Alberta do...) and you pull up to a red light on the main drag of airdrie (east lake bv.) next to the punk kid whos sister you were hittin on last night. hes acting cool in his honda civic listning to some "gangster rap" with his "hommies" thinking hes so cool cus hes just fixed his body kit that he rammed into a curb last week. Now this kid has seen "fast and the furious" one to many times and he looks over at you, checkin out the car, thinking its your grandmas (which at one point it was) he looks back at his friends and laughs, he then reves his imported engine. the tin can exhause becomes louder then his subs in the trunk. you then look over and smile at him and hit the switch opening your strait pipes. WWWHHHEERRRMMMMMM!!!!! WWWWHHHEEERRRRRRRREEEEEMMMMMM!!!! the light then turns green and you smoke him in a 5000 pound car that was once your grandmas.... whats the moral of the story, dont listen to rap :)

good times
 
#5 ·
The moral of that story is priceless. I like it. Mine was a '68 Plymouth Sport Furty though...and instead of electricity, I had a rope that came through a hole in the floor and I had to get out and use a metal hook to close the pipes back up, and it was in Chico, Ca. Music was the same, with a little alt. grunge thrown in and the same punk in the honda, yes. :)
 
#7 ·
leehern said:
so heres how it works, you out with your buddies crusining around saturday night in your huge boat listning to some classic county and western....(or atleast thats what the 16 year olds in Airdrie Alberta do...) and you pull up to a red light on the main drag of airdrie (east lake bv.) next to the love god kid whos sister you were hittin on last night. hes acting cool in his honda civic listning to some "gangster rap" with his "hommies" thinking hes so cool cus hes just fixed his body kit that he rammed into a curb last week. Now this kid has seen "fast and the furious" one to many times and he looks over at you, checkin out the car, thinking its your grandmas (which at one point it was) he looks back at his friends and laughs, he then reves his imported engine. the tin can exhause becomes louder then his subs in the trunk. you then look over and smile at him and hit the switch opening your strait pipes. WWWHHHEERRRMMMMMM!!!!! WWWWHHHEEERRRRRRRREEEEEMMMMMM!!!! the light then turns green and you smoke him in a 5000 pound car that was once your grandmas.... whats the moral of the story, dont listen to rap :)

good times
Yeah... well over here if you're in a ricer it's almost a prerequisite to listen to whiney rock. If you roll a Caddy or Town Car, you're expected to listen to rap. But yeah smoking ricers in a 5000 pound boat sounds like fun... smoking Mustang GTs and northstar Caddys is my plan though. The moral of the story, put a 150-200 shot on that 500 along with the other modifications and really get it moving.
 
#8 ·
ya man that was the plan anyways, the only problem is were building a 1969 firebird for the 1/4 mile track. I sware the only resone my dad wanted to buiild this car is so I would have no excuse for racing in the street. my dad wants to take my 500 and put it in his street rod hes lookin at buy (57 gmc truck). he dosnt like the idea of me "wasting" my money on this 500 he says hes going to wait till we get the firebird going then hes going to rebuild the 500 with a blower hoping for 800+hp... the only bad thing about that is that engine will never end up in my cadillac again.... I really cant complain but i just wanted some big hp in a mid 70's luxury car.... ohhh well....

my dad sugested me looking at a small block to put in my cadillac... something like a Ls1 so I would hopefull get better fuel economy, im a student and even when I drive that car easy I cant afford fuel. if you put a ls1 with a 6 speed and proper rear end gearing do you guys think I would get OK fuel economy, our goal is over 20mpg but I think the only way to get that good of fuel economy is by pushing it (with the engine off) anyways any coments on getting better fuel economy?

a Ls1 will still stomp ricers even in a 5000pound car,and those little V8s but out enought torque to definantly do a smokey burnout in the highschool parking lot :) Hondas What??????

has anyone put fuel injection on the 500ci? does that help any?

thanks
 
#9 ·
20 mpg sounds great but when you figure the initial cost of the swap (cost of engine, trans and gears) plus the work that it'll take to get it done, it's usually not worth it. It takes a long time for the fuel savings to show up against the swap cost.
I've said it before and I'll say it again.....if gas milage is at the top of your list for your car, you need a different car. Regardless of the engine, a 5000# car is not going to get "good" gas milage.
 
#10 ·
It's not like an LS1 would speed up the car. You get close to 50hp over a stock 500, in the process you sacrifice about 150ft.lbs which come in real handy when you're moving over 5000 pounds. To pull any performance moving such a heavy car with a small block, you'd probably need a 3.73 at least, a 6 speed to help with mileage would be a good idea then, but like lux said look at the cost of an LS1 plus a tranny and rear and then look at what an extra couple MPG will save you. You'd have to drive a million miles for it to pay for itself.

FI on the 500 would help with mileage a bit even over a perfectly tuned carb and it doesn't have to be that expensive if you go with a megasquirt and do it on the cheap. If you do FI, look for a factory FI intake, they flow pretty well and would save a lot of work. As for not wasting money putting some power into a big car, if you want to do it then do it. The way I look at it is if I build a 700hp mustang or other light car, there's always gonna be someone faster; If I build a big ass boat that's fairly fast, there's not gonna be many people with a faster big ass boat and if I lose to someone I can just ask "who are you gonna brag to about beating a 5000 pound grandma car?"
 
#11 ·
isnt that the truth, love racing ppl in my car, i have nothing to lose lol, I beat my friend in his dodge ram and all he could do was make up excuses, im like dude lets race again but suprsingly he dosnt want to lol!

I know what you guys are saying, the work involved to swap engines is going to be crazy, it can be done but really... why? I would love to have a little bit more tire spinning power (just cus tires are evil and must be destroyed) but ohh well.... Im going to work on my dad and see if he will let me add some performance to that engine, he says do whatever you want, its your money, but if he dosnt suport it ill never hear the end of it....

Heres my newest idea, PROPANE??? has anyone concidered this? what does it take to convert a big block to propane.... I hear the main disadvantage to propane is you need a large tank.... well we got huge trunks right, if you can fit 10 bodies in there you can fit a big tank... and the best part of propane is my dad sugeted the idea!! :) thats the biggest plue... the way I see it, I can put performane cams, ehaust, intake, carb (if they will work with propane) then i can save a little money running back and forth to town then when I pull up to a civic I can switch to premium fuel in my tank... can you do this? Ive just herd roomers


anyways thanks guy, keep it anti-rice
 
#12 ·
There was a 460 Lincoln that ran using propane on eBay awhile ago. It was a mark iv or a mark v, either one is LARGE.

Seriously, you should leave the a/c in. You'd need tons of power to be able to race head up with a respectable piece of rice or mexican rice. I don't know about Canada but in the USA you can't get your freon system recharged legally, so it would be a pain to put it back in. If you are going for weight reduction than uhh whatever there goes 30 lbs, but if you don't want to run the belt, just pull it off, as long as it isn't connected to something important. Or find some underdrive pulleys for your car. Try to leave the system in or if you are taking it out, discharge the freon and save it so you can recharge it.

Going 12s in the 1/4 mile is one thing but going 12s in the 1/4 when you run a full interior and have the moonroof open is something that is sweet.
 
#13 ·
leehern said:
Heres my newest idea, PROPANE??? has anyone concidered this? what does it take to convert a big block to propane.... I hear the main disadvantage to propane is you need a large tank.... well we got huge trunks right, if you can fit 10 bodies in there you can fit a big tank... and the best part of propane is my dad sugeted the idea!! :) thats the biggest plue... the way I see it, I can put performane cams, ehaust, intake, carb (if they will work with propane) then i can save a little money running back and forth to town then when I pull up to a civic I can switch to premium fuel in my tank... can you do this? Ive just herd roomers


anyways thanks guy, keep it anti-rice
If you go with propane, it will probably be gaseous carbureted propane because although liquid propane injection would kick ass by cooling the intake charge dramatically there is no way to do that other than basically making your own system. That was my plan for my 75 (still is but has been pushed back a year or 2). Carb'd propane on a stock engine will hurt performance by a tiny bit. The system will add weight, but hell what's a couple hundred pounds compared with 5000? Propane has an octane rating of 105 r+m/2. So if you swapped on some 76CC heads, you could run around 12.5:1 compression and make a lot more power than you started with, provided something doesn't break in the process. This rules out any chance of using pump gas ever again with that compression, but why would you want to anyway?

Any other modifications will work fine with propane, but with the 76cc heads and later pistons you can't go past .600 lift on a cam (with the stock rocker ratio.) I say propane is the way to go. While you're at it, hack up some monte carlo headers and weld them to a flange from a vendor, and cut the divider out of your intake manifold.
 
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