84 Cutlass Supreme Brougham Project

[84Fourdoor]

Hey guys. I'm new to the forum. About a year ago, I purchased an 84 Cutlass Supreme Brougham Sedan. She is HUGE. Under the hood is a wimpy 231 3.8l V6. It has a 3 speed auto transmission. This is my first car. I know very little about cars, but I have a good friend who is a smart and trustworthy mechanic. He said he would be willing to help me out with the ride.

She's got a bit of a transmission leak, and the car battery dies while it is parked. It's got a new battery, so the battery is not the problem. However, she's goin into the shop on thurdsay to get these kinks worked out.

I plan on making quite a few mods to this car including redoing the interior. I know she's only a V6, but that is a pro for me because I can't afford a gas hog. BUT.... I want to put performance parts on this car. Do they make performance parts for the V6? I really don't want to upgrade to a V8 due to gas. Like I said, I know little to nothing about cars, but these are a couple mods that I have been looking into. Feel free to boast your opinions on this.

-Supercharger
-Flowmasters- total new exhaust system
-Headers
-Shift kit

That's just what I'm looking into right now. I understand that these performance parts will more than likely bring down my MPG, but if I understand correctly, they should also increase my HP.

What do you guys think?

 

[Bigge91]

Re: 84 Cutlass Supreme Brougham Sedan

Hey guys. I'm new to the forum. About a year ago, I purchased an 84 Cutlass Supreme Brougham Sedan. She is HUGE. Under the hood is a wimpy 231 3.8l V6. It has a 3 speed auto transmission. This is my first car. I know very little about cars, but I have a good friend who is a smart and trustworthy mechanic. He said he would be willing to help me out with the ride.

She's got a bit of a transmission leak, and the car battery dies while it is parked. It's got a new battery, so the battery is not the problem. However, she's goin into the shop on thurdsay to get these kinks worked out.

I plan on making quite a few mods to this car including redoing the interior. I know she's only a V6, but that is a pro for me because I can't afford a gas hog. BUT.... I want to put performance parts on this car. Do they make performance parts for the V6? I really don't want to upgrade to a V8 due to gas. Like I said, I know little to nothing about cars, but these are a couple mods that I have been looking into. Feel free to boast your opinions on this.

-Supercharger
-Flowmasters- total new exhaust system
-Headers
-Shift kit

That's just what I'm looking into right now. I understand that these performance parts will more than likely bring down my MPG, but if I understand correctly, they should also increase my HP.

What do you guys think?

defenitly have more hp but ur gas i think would suffer alot with the supercharger and headers cause the headers will open up the exhaust...ud gain close to 20 to 30 just off of the headers...

 

[papabearxl]

Re: 84 Cutlass Supreme Brougham Sedan

For performance FEEL, your best bet is to change the rearend gear, to a lower ratio (ie you probably have a 2 series ratio...like 2.14:1, or 2.56:1. A better ratio for performance is somewhere numerically higher, say 3.08:1 or 3.42:1, etc) but you will lose gas milege on the highway, not as bad of mpg loss in city.....but still a loss.
Headers would work as far as motor, but like I said, changing your rearend gearing will give you the best, noticeable change, in my opinion. I am sure others will chime in.

By the way, WELCOME to the family...and post up some pics...we all love pics!

 

[84Fourdoor]

Re: 84 Cutlass Supreme Brougham Sedan

So the more HP, the less MPG? By the rearend gear ratio, are you talking about the differential? I would love to have a posi rear end. I'm not exactly sure on the specs of the differential it has on there now (stock) Are there other mods that I have not mentioned that increase HP and/or Acceleration?

 

[papabearxl]

Re: 84 Cutlass Supreme Brougham Sedan

Generally, the more HP, the less mileage IF you use that HP.....if you have more HP potential, but don't use it, and drive with your foot out of it, you can better your mpg.....but if you are wanting to hop it up, you aren't going to keep your foot out of it, I don't think.....and with it having the v6, in such a heavy car, you are going to have to keep your foot down to get it moving, much more so than if you had a v8.
Look at it like this....I saw this on Top Gear BBC:

They tested a Prius against a BMW M3 (400+ hp) for mileage....they had the Prius go around the track as fast as it could, and the BMW just had to keep up. Long story short, since the Prius had the gas to the floor, it was working a lot harder than the BMW's engine, and the result was the Prius got 17 mpg, and the BMW 19 mpg, in their test.
The BMW had to work less to follow the Prius and it's much smaller motor that was being pushed to the limit.


There are hop-ups for the v6, but would be at least as expensive, if not more than putting a v8 in there.IMHO...which is why I suggested the rearend (differential) gearing as your best bang for the buck.

 

[84Fourdoor]

Re: 84 Cutlass Supreme Brougham Sedan

Oh.. Okay. That helps everything make a bit more sense. So the question would be would a V6 (with performance parts) be more fuel efficient than a V8 (with performance parts)? Also, If the V6 "works harder" than a V8 would I get a louder exhaust sound?

 

[papabearxl]

Re: 84 Cutlass Supreme Brougham Sedan

Oh.. Okay. That helps everything make a bit more sense. So the question would be would a V6 (with performance parts) be more fuel efficient than a V8 (with performance parts)? Also, If the V6 "works harder" than a V8 would I get a louder exhaust sound?

You wouldn't get a "louder" performance exhaust sound.....it wouldn't alter the way your muffler and pipes sound already.

If you put headers, 4 barrel intake and carb (if it doesn't already), and good flowing muffler (also to help your sound if you want), good tune up with plugs wires, check your timing, you should get a performance gain.....but still without heavy, expensive modifications, that v6 isn't going to be a powerhouse in a 3700lb car.....I had one in my 83 Cutlas Cruiser.....
You can try finding an intake and carb for a 4.1v6 on eBay, Craigslist, or a PullAPArt type yard, since I believe they are more plentiful, and the aftermarket stuff for the 3.8v6 is just crazy expensive.

For getting in a good range of power with the v6 to move that car, you are talking building/strenghtening the motor, headwork, turbos or superchargers, etc, etc.....then you need to think about the rearend and transmission.....
Hope it doesn't discourage you......really.
You can do whatever you want to with these cars, it just takes planning, timing, knowledge and money....
If you aren't just hellbent to keep the v6, I would save my money and swap a v8 in there. Sadly, I think it would cost you more money to hop up the v6 to get the power you want, than swapping in a v8. I know you are new to cars, and the prospect of swapping motors is daunting, but that is the way I see it.

If I am wrong, someone WILL chime in........good luck.

 

[84Fourdoor]

Re: 84 Cutlass Supreme Brougham Sedan

I would definitely like to put a V8 in this car in the future. But for now, it's my first car; I need a semi-fuel efficient car. I understand that if I wanted a fuel efficient car, I shouldn't have bought a G-Body. But I love G-Bodies I want to use this V6 as long as I can, so for now, maybe I should just put Headers and Exhaust on it until I can buy a V8?

 

[papabearxl]

Re: 84 Cutlass Supreme Brougham Sedan

Sounds reasonable to me.... 8)

In the meanwhile, you can say you have a car you like, work on it when you can, and enjoy it.
🙂

 

[84Fourdoor]

Re: 84 Cutlass Supreme Brougham Sedan

How would I be able to identify the Carburetor model on the car?