mrowpolitron

I have a 1980 L82 automatic with 53,000 miles on the original engine and several people have told me that I should have the smog pump and all pollution stuff removed so I can have far more power and performance. Is this a good idea or am I heading for some trouble?

murraybs

switch the distributor advance from ported to manifold vacuum (as simple as changing ports on the carb), remove the smog pump belt, pull the pump and bracket and disconnect the vacuum going to the EGR.

It's that simple. If you leave any vacuum ports open, be sure to plug them.

blk79nj

It depends on you what you want, and what the laws are in your state. I may be against the law where you live, such as California.

If you are looking to keep the car orginal, I would recommend to keep it in place.

mrowpolitron

Thanks for the help! Will this increase my HP, and if so, how much?

murraybs

optimistically: 20ish at peak power.

stingr69

You will not notice any HP difference if you remove the smog pump. Try it with the belt on and again with the belt off and see if you think it is worth your time and effort.

The catalytic converter needs to be updated or removed first. That mod WILL make a noticeable difference. Best bang for the buck if you have not alredy taken care of it.

-Mark.

mrowpolitron

Thanks to all for you help! Mark.

jb78L-82

As long as you keep everything that you remove for yourself or anyone else in the future who may want to buy your car, I would consider removing all the emissions "stuff" on your car since it only hurts performance. For an optimum performance gain, I would also add 2.5in true duals with no cats, performance mufflers of your choice, and a different exhaust manifold of some type such as stock GM exhaust manifolds with no AIR ports (not optimal especially since, I think, your year has a tubular exhaust manifold similiar to headers, shorty headers (I have McJack's Headers which are an exact copy of the stock manifold in a shorty header), or full length headers (not my choice for street vehicles since the performance gain is mostly high RPM and ground clearance issues as well as hooking up to the duals. Speaking of the AIR pump, just removing the belt does not reveal the real performance gain from removing the obstruction in the exhaust stream that the AIR ports present where the exhaust exists the head. I was shocked to see how far the ports extend into the head when I removed mine and put on the McJacks headers. With headers of some sort, Monza turbo mufflers, and 2.5in true duals, I was shocked by the performance gain I got on my 78 L-82. Probably, +40 HP gain. The stock exhaust system with a monstrous restrictive cat, polluted and obstructed by the AIR pump, and EGR value is VERY restrictive. The biggest bang for your buck is ripping that junk out and replacing it with the latest technology. You will not be disappointed!

fauxrs2

only your original catalytic convertor is any real theif of power...the rest are negligible at best - lots more power is a joke.. you will not see lots more power...you wont even see 20 (IMO) unless you have an original pellet convertor that is partially plugged.

EGR doesnt work at WOT so it steals nothing there.
Air pump - next to nothing
CAT - could be big if its partially plugged.

jb78L-82

As an example of the horsepower gains that one can expect with a more efficient and cleaner intake charge, the best example one can look at is a 1974 L-82 corvette with no AIR pump, no EGR value diluting the incoming air with exhaust dilution, and true duals with somewhat restrictive stock mufflers as compared to a 1978 L-82 with pretty much the exact same engine, heads, compression ratio, and cam as the 74 L-82 but with a stock Y pipe exhaust with a cat, AIR Pump, EGR value, and restrictive mufflers. The 1974 L-82 is rated at 250 Net HP versus the 1978 L-82's rating of 220 net HP. If my math is correct that is +30HP with no other changes other than the exhaust system and elimination of the AIR pump and EGR valve. IF you improve on the 74's exhaust with better flowing mufflers and headers on the 78 L-82's engine, a +10 HP gain is reasonable bringing the overall improvement to about +40HP as stated above. Your driveability, idle, and mileage will also improve with the changes stated. You win all the way around! Incidently, the 80 L-82 has less restrictive mufflers than the 78 L-82 and tubular exhaust exhaust manifolds with a rating of 230 net HP, exactly the +10 HP gain over the 78 L-82's 220 net HP. Possibly, GM knew something about exhaust restriction?

Mike Ward

A smog pump takes approx. 1 (one) HP to operate. Watch you don't snap your neck with all that extra power............

fauxrs2

All true, though I suspect the vast majority of the improvement is due to swapping to a freeer flowing dual exhaust vs the single exhaust and less to the smog equipment.

The removal of EGR and AIR is NOT EVER going to net anybody 30 hp - 20hp or even 10HP..by itself...on the other hand changing to headers - dual exhaust and freeer flowing mufflers is a grand improvement that I wholeheartedly endorse as good for performance gains. of the 40hp gained.. perhaps as much as 5hp comes from the deletion of AIR and EGR. (and that is being generous IMO, its probably closer to 3)

The improvements to the 80 L-82 have nothing to do with emissions controls and everything to do with freer flowing exhaust. The OP asked if removing a few emissions controls would net him "far more power and performance" that is the fallacy I'm talking about.. I agree with you that opening up the exhaust by updating to true duals, headers.. etc.. would be a huge improvement over the factory setup. Setting aside the legality since we dont know where the OP resides. Hw could still run modern Cats since they too are now minor impediments to exhaust flow, unlike the old "pancake-pellet-style" cats that our cars shipped with.

jb78L-82

Agreed! Don't discount the exhaust obstruction that the AIR ports create in the head/exhaust manifold. The AIR pump itself, providing more clean air into the exhaust certainly helps create better combustionin the exhaust, and yes, the drag from the belt is minimal on the AIR pump,minimally effecting useable horsepower. As for the EGR valve diluting the incoming fresh air charge not having any effect on power, driveability, and mileage at throttle openings short of WOT, I would tend to disagree since anytime you "posion" the incoming air, there will be a negative effect. Most "experts" I have talked with claim about 5HP which isn't much but does not take into account the other parameters of idle quality, driveability, and effect on engine temperature.

fauxrs2

Indeed, I dont discount the possibility that the tubes are also an obstruction, I simply dont have any empirical evidence that they are anything even remotely significant.

All I am trying to do is disabuse the OP from the belief that he will be making great strides in power output by removing these items. He would be far better served to follow your outline for a better exhaust, in which EVEN RETAINING the emissions controls could net him 30-40 hp which is several orders of magnitude greater than just removing emissions controls.

There are full length headers with air tubes that dont project deep into the valve bowls like the factory ones do that will get you through the testing in CA. Hi flow cats are at best minor impediments nowdays.

So even if we accept that EGR is worth 5hp (I dont agree but will defer) that the air pump itself is 1 and the tubes in the airflow is also 1...removeing those items amounts to 7hp which in my book doesnt qualify as "far more power" in fact 7hp is something that you can only detect on a dyno or perhaps several runs on a dragstrip.

To the OP - Duals man.. thats what you want... or if you have the factory CAT - get rid of it in favor of a modern hi-flow unit

jb78L-82

Good points. Thanx for the dialogue!

fauxrs2

no worries

moondoggy200

does anyone know if the 1974 L48 came with Catalytic converters???? Thanks moondoggy outttt.

my 76 ray

Catalytic converters first appeared in 1975.

Gale Banks 80'

Go to e-bay and see how much some of the emissions parts sell for for people who want them to re install to put it back the way it came from the factory. Also keep in mind You can buy a new corvette with 638 HP with all the emissions hooked up.

AGVI