Welcome to the Corvette Forums at the Corvette Action Center!

Question: What can I get rid of?

jpburks

Member
Joined
Aug 9, 2009
Messages
19
Location
Gainesville, FL (Go Gators)
Corvette
1981 Hardtop Midnight Blue
I am the very proud new owner of a beautiful 1981 Vette and I have now reached that point in which I want my baby to go just a little faster and to look a little nicer under the hood. So, my question to "the board" is, what can I remove from under the hood (other than ac) that will either boost my power or will make the engine compartment look nicer. Personally, the look of the engine is a little more important to me at this point, and the maze of tubes and wires is not only detracting from the look of the compartment, but it is also more than a little frustrating. I appreciate all help and hope to hear from you all soon.

P.S. As far I know, this car is completely stock, so it has everything that it originally came with.
 
Get rid of the stock exhaust and replace it with a good set of headers , 2 1/2" duals and free flowing mufflers. Take out the smog pump. This by itself will noticeably improve both power and fuel efficiency, and I believe it also reduces pollution. It will also clean up the engine compartment nicely.

Removing the EGR does not do much looks or performance wise.

You may be tempted to remove the evap canister with it's "Medussa's head" of vacuum hoses, but don't. It will not help performance any and will actually cause heat soak starting problems. Also, it actually cuts down pollution by trapping and re-using fuel vapors.

God bless, Sensei
 
Thank you Sensei,

That is great information! :) I will definitely get on the smog pump as soon as I can. I have to figure out all the connections and how to properly block them. As for the exhaust, do you have any recommendations? I need something nice but inexpensive. Im not looking for 500 HP, I just want to let a few more of those horses out of the stable. ;) Thanks again!!
 
I got a set of ceramic coated shorty headers on Ebay for around $135 and put them on myself. The driver's side one had to be slightly "massaged" at the collector to clear the motor mount. I got a pair of Summit turbo mufflers for about $20 each. They look stock and have a mellow rumble that is not too loud in the cockpit. I had a local mom and pop muffler shop that is known for quality hot rod work fab a set of 2 1/2" duals for $125. This was almost five years ago. The headers still look like they did the day I installed them and the whole system is still good as new, all for around $300.

God bless, Sensei
 
Contrary to myth, a smog pump set up only uses about 1 HP to operate. it is not the great evil beast it's made out to be. An EGR requires no power to operate and carries no performance penalty.

Your engine is typical of late 70s and early 80's low compression set ups to meet the lack of high octane no lead fuel (at the time) and new pollution regs.

Swapping exhaust will help, but you need to look at new heads, and a more aggressive cam to get some serious power. :thumb
 
Contrary to myth, a smog pump set up only uses about 1 HP to operate. it is not the great evil beast it's made out to be. An EGR requires no power to operate and carries no performance penalty. :thumb

While I agree that you may not see any noticeable gain in power by removing these and EGR may actually reduce pollutants by lowering combustion chamber temperatures, I have to make a couple of comments here anyway.

1. I don't know how many HP it takes to actually turn the smog pump, but the system itself is BAD! You notice they do not inject air into the exhaust on new vehicles anymore. It was all just a way for automakers to comply with federal regulations on pollution measured by percentages of pollutants in the exhaust. It never worked as described (completing the combustion of unburned fuel in the exhaust), it just added air to dilute the % of whatever was measured at the tailpipe. It was all a lie and it actually causes pollution. It was the reason gas mileage dropped like a stone on pollution controlled vehicles during this period. It is an intentional exhaust leak that kills performance and fuel economy. GET RID OF IT!

2. EGR requires no HP to run and may reduce pollutants, but you can not achieve peak horsepower when the engine is eating its own waste.

God bless, Sensei
 
...P.S. As far I know, this car is completely stock, so it has everything that it originally came with....

Leave her that way. If she's managed to stay unmolested all this time, she has a right to survive.

There are less and less unmolested originals every day.


:thumb
 
While I agree that you may not see any noticeable gain in power by removing these and EGR may actually reduce pollutants by lowering combustion chamber temperatures, I have to make a couple of comments here anyway.

1. I don't know how many HP it takes to actually turn the smog pump, but the system itself is BAD! You notice they do not inject air into the exhaust on new vehicles anymore. It was all just a way for automakers to comply with federal regulations on pollution measured by percentages of pollutants in the exhaust. It never worked as described (completing the combustion of unburned fuel in the exhaust), it just added air to dilute the % of whatever was measured at the tailpipe. It was all a lie and it actually causes pollution. It was the reason gas mileage dropped like a stone on pollution controlled vehicles during this period. It is an intentional exhaust leak that kills performance and fuel economy. GET RID OF IT!

2. EGR requires no HP to run and may reduce pollutants, but you can not achieve peak horsepower when the engine is eating its own waste.

God bless, Sensei

I think your understanding of each system is slightly incorrect, but please believe what you want. As I said, it's not the great evil beast of myth and legend.

1. AIR pump. I'll cheat and post a link from wikipedia which gives an accurate summary:
Secondary air injection - Wikipedia, the free encyclopedia

2. The EGR system is vacuum controlled and is out of the loop during low vacuum situations, like WOT.

:thumb
 
I think your understanding of each system is slightly incorrect, but please believe what you want. As I said, it's not the great evil beast of myth and legend.

Agreed.

Maybe all of that was true when first introduced...but by '81 that was not the case.

I tend to go with 6880 Mike....leave her alone. :)
 
My simple thinking. Unburned fuel will not burn by injecting fresh (cold) air, but when polution is measured by volume, injecting air will increse the volume and then reducing the polution. Just my thought.

My idea, do what you want with it.

Groeten Peter
 
The actual volume of air that's injected is very small, but it's sufficient to allow hot unburnt vapours to re-ignite and complete enough of the combustion process to pass emission regs. The volume of air injected is not enough to dilute the total air mass to achieve this. Such a cheap trick wouldn't fool anybody anyways ;)
 
The actual volume of air that's injected is very small, but it's sufficient to allow hot unburnt vapours to re-ignite and complete enough of the combustion process to pass emission regs. The volume of air injected is not enough to dilute the total air mass to achieve this. Such a cheap trick wouldn't fool anybody anyways ;)

And Obama is not a socialist!
 
I look at this way its your car do with it as you please. Dont throw away anything! But im like you a stock 81 vette will get chewed up and spit out by just about anything with wheels on it nowadays. And I cant stand driving around in a car that looks fast but has to cower and hide when a srt neon or a minivan pulls along side. Do the exhaust first and then and this may depend on your emissions testing or lack of it,change over to a non computor controlled carb and distributor.Truthfull with about 500 dollars you could gain almost 100hp by changing the the cam and doing the before mentioned mods.A few hundred more for good heads and you could make a easy 350 to 400 hp and still be streatable and hold your own if and when you need to.Sure stock is nice and all but we dont have a ton of power to start with and anything you do is going to help.
 
When I bought this 81 it had all the original equipment on a non matching engine. Air pump complete with broken mounting brackets, exhaust manifold complete with bad welds, electronic q jet complete with external fuel leaks. The car ran ok but by the time I added all the cost for vac hoses, failed sensors, carb overhaul ect., Ive still got a engine that cant be tuned for performance. To date the pcv and evap can is all thats left and Im not regetting the swap. Engine runs much better and the magnaflow mufflers scare of the ricers. Cam and heads to come this winter :beer
 
by the time I added all the cost for vac hoses, failed sensors, carb overhaul ect., Ive still got a engine that cant be tuned for performance.

The cam, heads and exhaust on the '81 were the performance killers, not the carburetor and sensors. I'm in the 350-400 hp range with stock carb, distibutor and computer control.

God bless, Sensei
 
Ok Sensei, but can you tell me in detail the kind of head ,the piston and everythings?If you can!
Today i've put on my 81 a new dual exhaust system but there's no difference in performance, only sound change!

Have a nice day, Alex.
 
I don't know what exhaust you put on, but my exhaust system made a HUGE, feel it in the seat of your pants difference. Here is a fairly detailed list of mods I've made to my car:

Carburetor:
Perforated Secondary Pickup Tubes (like Cobrajet)
Open Idle adjustment screw holes to 3/32"
Secondary fuel channel restrictions drilled to 3/16"
Edelbrock 1951 CE (.0410") Secondary Rods
Secondary air valve stop removed for full opening
Secondary air bleeds driven in to proper standing height
Shortened accelerator pump rod and linkage adjusted for maximum pump shot
Throttle linkages adjusted for optimum opening.
K&N 1500 air filter

Engine:
Dart Iron Eagle 180cc intake runner, 72cc chamber heads. Chambers polished.
Speed-Pro Hypertuetic flat top pistons
Comp Cams XE262H cam
Comp Magnum roller tip rocker arms.
Edelbrock 2101 Performer Intake.
Exhaust:
1 5/8" primary ceramic coated block hugger headers
2.5" true dual exhaust, turbo mufflers, no cats.
AIR, EGR removed.
Hypertech Thermomaster Power Chip (180 degree thermostat)

MSD 6A ignition box
Bow Tie Overdrives Level II TH700r4 transmission
Eurethane motor mounts, front A-arm bushings, and stabilizer bar bushings
Spreader Bar

God bless, Sensei
 
Without doing anything else , A cheap way of getting some extra perceptible voom is to swap out your low stall with a higher one , the car as is is a dog in terms of performance.
I have deleted all smog stuff , all aircon stuff , run a 270H cam with ally edelbrock heads , bumped CR to 10:1, Use decent headers and a Holley 770 street avenger carb - electronic dizzy and MSD6 al , 2500 rpm stall , 3.55 rear end and the car is now a 12 sec street warrior that is very driveable.
My engine bay looks real neat to
 

Corvette Forums

Not a member of the Corvette Action Center?  Join now!  It's free!

Help support the Corvette Action Center!

Supporting Vendors

Dealers:

MacMulkin Chevrolet - The Second Largest Corvette Dealer in the Country!

Advertise with the Corvette Action Center!

Double Your Chances!

Our Partners

Back
Top Bottom