1987 350tbi smog delete. What needs to be removed, plugged or any of that good stuff?

[RyanNewberry]

I got a 87 1/2 ton 4wd I’m slowly restoring. I’ve been meaning to do a smog delete since the day I bought it but I was focusing on the bigger parts of the project. I really want a very clean engine bay. The truck runs like a top right now, I have a set of headers to put on it with true duals. The performance upgrades for the engine will be coming in the near future with flat tops, cam, and a Ecm chip from Tbi chips. I just want to know and make sure that I remove everything and not accidentally something that’s going to ruin the performance of the stock engine now. So, now that I rambled, any pictures, lists, videos, absolutely anything, advice, hate mail, it’s all good. Thanks much. -Ryan

[mongocanfly]

I stripped all that off both my trucks with no ill effects...sorry ..no pics

[RyanNewberry]

Mongo- you got a rough idea or list ish.. of everything you did?

[Dead Parrot]

Stuff usually good to leave on a street truck:
PCV: Really helps keep the oil clean by pulling the blow by out of the crankcase. Most carbs and injections systems are calibrated for the presence of PCV.
THERMAC: helps with cold weather warmup and lessens the chance of carb icing in cool humid weather. A modern computer/injector system may not need.
Charcoal canister for gas tank vent. Those gas fumes are going somewhere, might as well use the factory system. Doesn't mean you can't move it to a out of the way spot in the engine bay.
Did you keep the O2 sensor?

[RyanNewberry]

Yes I did

[RyanNewberry]

Oh and about the thermac, are you talking about the air intake with the valve, if you are that was removed right away replaced wth a Edelbrock filter, truck starts great even in -30 degree weather in our Wisconsin winters. So that’s not the biggest issue.

[sweetk30]

fyi : you need the o2 sensor with the tbi injection .

if the stock pancake cat is still under the truck there a HUGE restriction of power .

[RyanNewberry]

I kept the o2 sensor, I actually welding in a bung right on the new headers, I haven’t swapped out to headers yet, it’s still on stock manifolds right now. I just want to get the smog delete project done since the weather has been decent and I have some time off.

[DieselSJ]

Originally Posted by sweetk30

fyi : you need the o2 sensor with the tbi injection .

if the stock pancake cat is still under the truck there a HUGE restriction of power .

^^This^^

I used a Magnaflow high-flow unit and picked up mileage and performance.

Keep in mind that even though you might not have a local smog inspection program, it is still a federal offense to remove any emissions devices for something that will be driven on public roads. The eco-nazis love to see posts like this so they can argue for more inspections.

[Dead Parrot]

Originally Posted by RyanNewberry

Oh and about the thermac, are you talking about the air intake with the valve, if you are that was removed right away replaced wth a Edelbrock filter, truck starts great even in -30 degree weather in our Wisconsin winters. So that’s not the biggest issue.

Yep, that's it. Keep that OEM intake and the little riser pipe. Might be of value to someone doing a restore to OEM appearance.

Assuming the cat(s) will get lost when you do the header/duals but that pancake converter is a power robber. Picked up 3 mpg when I swapped an empty pancake with a cheap honeycomb type on a Camaro.

[RyanNewberry]

Yea chances are the cats will be gone completely, I’m doing a custom side exit exhaust, not quite sure on what size tubing yet. I had 3” on my last truck and it performed well but that truck also had 400hp. What about the egr valve, can I block it off without issue or should I keep that?

[WyattTX]

Originally Posted by DieselSJ

^^This^^

I used a Magnaflow high-flow unit and picked up mileage and performance.

Keep in mind that even though you might not have a local smog inspection program, it is still a federal offense to remove any emissions devices for something that will be driven on public roads. The eco-nazis love to see posts like this so they can argue for more inspections.

Regardless what we say, they still want us to have our trucks destroyed, and drive electric cars, that dont help anything due to the source of the electricity. Do not be intimidated by them, they are gulible fools that belive whatever some well paid politician tells them.

[hatzie]

I'd keep Cats, Charcoal can, PCV, EGR, and Thermostatic Air Cleaner on a TBI engine.

You can get free flowing non-stock cats that'll still do the job without playing havoc with the power output like the restrictive heavy GM pancakes.

The charcoal canister lets you burn the fuel off that would otherwise evaporate into the air and stink up the garage. It has no negative operational effects.
PCV keeps the crankcase under light vacuum. It recycles blowby gasses and evaporating condensation extending the oil life. The light vacuum also keeps old seals etc from leaking as soon as they would if it was just vented to the atmosphere.

EGR is used to slightly cut the combstion temps to decrease NOX. Why is that good for us? We can run cheap crappy fuel and the ECM will use EGR along with ESC to slightly control Detonation. If you kill off the EGR and ESC you'll need to run slightly higher octane fuel. Not the end of the world but something to be aware of.

That pretty Edelbrock or Mr Gasket or ... compact exposed pleat air filter is actually costing you power. It's intake is directly in the HOT air flow from the radiator fan. Performance folks driving everything from rice burners to Corvettes pay good money for cold air intakes. Why? Cold air has more Oxygen per cubic inch than warm air. The stock GM RV series, and CK series from 1986 back to about 1982 or 83, thermostatic air cleaner (Therm-AC) already has one cold air intake hose that connects to a water rejecting baffle on the RH side of the radiator to take in air from the grille that hasn't passed through the radiator. Some folks actually add a second hose connection to the air cleaner, a second cold air hose, and a radiator support passthrough baffle to the LH side of the engine bay. Very effective cheap CAI with plenty of airflow.
If the temps are above freezing the Thermostatic Air Cleaner (Therm-AC) valve stays in outside air mode so it has ZERO effect on summer performance. Why? It only activates below 35°F or so to keep the throttle blades from icing up and locking the throttle butterflys open or closed.
The Thermostatic Vacuum Switch in the intake or thermostat housing further limits the Therm-AC so it can only operate til the engine is up to operating temp.
On 86 and prior trucks the TVS also cuts vacuum to the Quadrajet secondaries til the engine is up to temp so you don't load up the combustion chambers and spark plugs with carbon.

Don't use the washable K&N etc air filters they look slick but they let way too much dirt through. FRAM, while not the best oil filter manufacturers, makes one of the best air filters available. Don't believe it? Have Blackstone or another lab run a Used Oil Analysis using the K&N for one full oil/filter change interval and a FRAM in the stock air housing for another oil change. Then compare the dissolved solids and silica numbers from one to the other. More of either is BAD.

[RyanNewberry]

Originally Posted by hatzie

I'd keep Cats, Charcoal can, PCV, EGR, and Thermostatic Air Cleaner on a TBI engine.

You can get free flowing non-stock cats that'll still do the job without playing havoc with the power output like the restrictive heavy GM pancakes.

The charcoal canister lets you burn the fuel off that would otherwise evaporate into the air and stink up the garage. It has no negative operational effects.
PCV keeps the crankcase under light vacuum. It recycles blowby gasses and evaporating condensation extending the oil life. The light vacuum also keeps old seals etc from leaking as soon as they would if it was just vented to the atmosphere.

EGR is used to slightly cut the combstion temps to decrease NOX. Why is that good for us? We can run cheap crappy fuel and the ECM will use EGR along with ESC to slightly control Detonation. If you kill off the EGR and ESC you'll need to run slightly higher octane fuel. Not the end of the world but something to be aware of.

That pretty Edelbrock or Mr Gasket or ... compact exposed pleat air filter is actually costing you power. It's intake is directly in the HOT air flow from the radiator fan. Performance folks driving everything from rice burners to Corvettes pay good money for cold air intakes. Why? Cold air has more Oxygen per cubic inch than warm air. The stock GM RV series, and CK series from 1986 back to about 1982 or 83, thermostatic air cleaner (Therm-AC) already has one cold air intake hose that connects to a water rejecting baffle on the RH side of the radiator to take in air from the grille that hasn't passed through the radiator. Some folks actually add a second hose connection to the air cleaner, a second cold air hose, and a radiator support passthrough baffle to the LH side of the engine bay. Very effective cheap CAI with plenty of airflow.
If the temps are above freezing the Thermostatic Air Cleaner (Therm-AC) valve stays in outside air mode so it has ZERO effect on summer performance. Why? It only activates below 35°F or so to keep the throttle blades from icing up and locking the throttle butterflys open or closed.
The Thermostatic Vacuum Switch in the intake or thermostat housing further limits the Therm-AC so it can only operate til the engine is up to operating temp.
On 86 and prior trucks the TVS also cuts vacuum to the Quadrajet secondaries til the engine is up to temp so you don't load up the combustion chambers and spark plugs with carbon.

Don't use the washable K&N etc air filters they look slick but they let way too much dirt through. FRAM, while not the best oil filter manufacturers, makes one of the best air filters available. Don't believe it? Have Blackstone or another lab run a Used Oil Analysis using the K&N for one full oil/filter change interval and a FRAM in the stock air housing for another oil change. Then compare the dissolved solids and silica numbers from one to the other. More of either is BAD.

Man where do I start, all I can say is you are a GOD for the wealth of knowledge of these trucks that you have. Thanks for everything. Going along with what you said:

The exhaust is stock yet and I haven’t touched it, plans are to put a set of long tubes on and some true duels exiting out sorta below where the passenger side fuel door would be.”yes I’m hacking a hole in my mint box side”. For cats I haven’t decided to loose them completely or use some high flow version. Suggestions welcome!

I plan to keep the Pcv as of right now. The charcoal can I will possibly relocate because it’s just so dang ugly. I didn’t use the pretty air cleaner really for looks, more or less I’ve had them on almost every truck and my Chevelle and I honestly have roughly 10 brand new ones in the boxes yet.

The EGR I haven’t determined quite yet, some guys hate them and have some valid points to remove them. If they are true granted. I run premium fuel on every tank to start with so the crappy fuel point doesn’t matter to me but I didn’t know that to start with so thank you. With running a higher octane premium fuel, is there still a advantage to having that EGR valve or no????

One other question... I noticed when you wrote about deleting the egr you touched on killing the esc also. Will the esc work without the egr valve or do they get deleted sort of like a “package deal”? Or since I run higher octane anyway can I just delete both completely without a issue?

[hatzie]

ESC will pull timing based on input from the knock sensor. ESC will run without EGR but they can and do work together at times.
Without the additional lowered combustion temps from the EGR system, when the EGR is active, ESC could end up pulling more advance to reduce possible detonation costing you some performance.

As far as the air cleaner goes... The "Looks Stock" using modified factory parts CAI is not a new idear and it doesn't need to look like crap.

1987-91 Squarebody Shop Made Dual Snorkel CAI and serpentine belt


3rd Gen F-Body with home brew dual snorkel CAI


GM G-Body Shop Made Dual CAI


Fox Body Mustang Shop Made Dual Snorkel CAI

[DieselSJ]

Originally Posted by RyanNewberry

Man where do I start, all I can say is you are a GOD for the wealth of knowledge of these trucks that you have. Thanks for everything. Going along with what you said:

The exhaust is stock yet and I haven’t touched it, plans are to put a set of long tubes on and some true duels exiting out sorta below where the passenger side fuel door would be.”yes I’m hacking a hole in my mint box side”. For cats I haven’t decided to loose them completely or use some high flow version. Suggestions welcome!

I plan to keep the Pcv as of right now. The charcoal can I will possibly relocate because it’s just so dang ugly. I didn’t use the pretty air cleaner really for looks, more or less I’ve had them on almost every truck and my Chevelle and I honestly have roughly 10 brand new ones in the boxes yet.

The EGR I haven’t determined quite yet, some guys hate them and have some valid points to remove them. If they are true granted. I run premium fuel on every tank to start with so the crappy fuel point doesn’t matter to me but I didn’t know that to start with so thank you. With running a higher octane premium fuel, is there still a advantage to having that EGR valve or no????

One other question... I noticed when you wrote about deleting the egr you touched on killing the esc also. Will the esc work without the egr valve or do they get deleted sort of like a “package deal”? Or since I run higher octane anyway can I just delete both completely without a issue?

I'd be interested to hear what the "valid" points are for removing EGR? EGR is only commanded in light throttle or cruise and has zero negative effects on performance. My TBI 454 picked up about 1/2mpg (that is significant when you are talking 10 vs 10.5) consistently since I worked out my EGR issues. EGR does not have a negative effect on power.

Contrary to what people say, you can have a clean burning engine that makes great power.

As for running premium...why? Do you have detonation issues on lower octane? Ideally you want to run the lowest octane possible. Higher octane does not add power, and can actually hurt power due to the slower burn.

Hatzie was on the money with the open element filter - you will lose more power than you would ever gain.

Personally I would avoid TBIChips and go with http://www.dynamicefi.com/ and tune it yourself.

[RyanNewberry]

Originally Posted by DieselSJ

I'd be interested to hear what the "valid" points are for removing EGR? EGR is only commanded in light throttle or cruise and has zero negative effects on performance. My TBI 454 picked up about 1/2mpg (that is significant when you are talking 10 vs 10.5) consistently since I worked out my EGR issues. EGR does not have a negative effect on power.

Contrary to what people say, you can have a clean burning engine that makes great power.

As for running premium...why? Do you have detonation issues on lower octane? Ideally you want to run the lowest octane possible. Higher octane does not add power, and can actually hurt power due to the slower burn.

Hatzie was on the money with the open element filter - you will lose more power than you would ever gain.

Personally I would avoid TBIChips and go with http://www.dynamicefi.com/ and tune it yourself.

I run premium in all my vehicles. I never like ethenol and it for some reason seems to gum up carbs and tbi units. I have done it my entire life. Just seem to have good luck with it I guess. I understand the open filter but I’m not really looking for power quite yet. Eventually the new engine will be built and we will go from there. The egr I’m on the fence with, I’ve heard many different ideas with t and I appreciate them all.

[DieselSJ]

Originally Posted by RyanNewberry

I run premium in all my vehicles. I never like ethenol and it for some reason seems to gum up carbs and tbi units. I have done it my entire life. Just seem to have good luck with it I guess. I understand the open filter but I’m not really looking for power quite yet. Eventually the new engine will be built and we will go from there. The egr I’m on the fence with, I’ve heard many different ideas with t and I appreciate them all.

Nearly 100% of motor fuel in the US has ethanol. Unless you have one of the few stations that sells non-blended, your premium fuel will have up to 10% ethanol, just like the lower grades of fuel.

[hatzie]

Real gasline isn't an outrageous claim outside The Peoples Republic of California and the Eastern US Iron Curtain states from Maryland/DC to New Jersey, Connecticut, Taxachusetts, and Nuke York.

I have two stations in easy driving distance that sell REAL gasoline but only in high octane.
I run it in my tuned LS4, mower, chainsaw, backpack blower, line trimmer, boat, sled, and ATV. The Dodge and F250 may need to run it. Won't know til they are running again.

[Dead Parrot]

Here in OKC, I have an OnCue a few blocks away that has a battery of select your grade real gas pumps. 87, 89 and 91 varieties. Plus 87 E10 and E85. Other pumps have the full range of E10 varieties. In some parts of town, harder to find E10 then real gas.

Have always ran the cheapest stuff I can in my 75. Mostly stock 350. Never noticed much difference.

The real gas does help keep small motor gizmos like lawn mowers and weed whackers running better.

[hatzie]

Ethanol has lower BTUs than gasoline. The LS4 gets 2-3mpg less on E10 fuel. The Polara 500 has a high compression 383 so it knocks on less than 92 so I run the REAL 93 in it.

My 2014 Suburban 5.3l does perform better on ethanol adulterated fuel but its designed to run on it. It still drops 2-3 mpg on E10 alcohol fuels tho.

Ethanol is rough on the motorsports and small engine carburetors even dosed with Seafoam stabilizer. It remains to be seen how well the antiques will do even if I'm dosing the fuel with Seafoam.

Real 87 would be the bees knees.

[Hart_Rod]

Old thread, but thought I would ask anyway. Does anyone know what size and where to source the 2 plugs required to plug up the hole in each manifold? I believe they are metric. Thanks in advance!

[Corts60]

Originally Posted by Hart_Rod

Old thread, but thought I would ask anyway. Does anyone know what size and where to source the 2 plugs required to plug up the hole in each manifold? I believe they are metric. Thanks in advance!

I think if I remember correctly that a Cummins 5.9 oil drain pan plug is the same metric thread for that.

[Hart_Rod]

Originally Posted by Corts60

I think if I remember correctly that a Cummins 5.9 oil drain pan plug is the same metric thread for that.

Thanks! I grabbed 2 at the parts store and the fit perfect, . For future questions on this matter, the part number is Dorman 652886.