I'm looking at a 1986 Trans Am, for sale.

It was originally a Feedback Rochester 4V, 305 LG4, auto trans car. Somebody replaced the original engine with the pictured engine, which has a functioning mechanical fuel pump, reportedly a manifold vacuum leak , fuel in the oil and runs bad. The SMOG stuff was removed from the engine, as you can see.


Assuming the 350 in it is bad, and the ECU is present, what would be a productive, pretty easy, swap, that would pass SMOG? From what year and model vehicle could I find a complete "Take Out" LG4?

Knowing the original LG4 was pretty low HP, what would a productive 350 swap be?

I have ruled out a LS1 swap, because I believe it would be too much work. I would be building the car for resale.

Thanks.

 

Above is what is what is in the TA now.

 

From what I read (there is a thread on-going), the '87 LG4 is the best of all LG4 engines in the Camaro/Firebird platform. You would need to find a '87 donor car with low miles. But that would be highly cost prohibitive. Unless wrecked, a low milage '87 maybe more expensive than the '86 Trans Ams is worth? Plus - after that it is "only" a LG4. I have no hate for the 305 (still have the original LU5 in my car currently), but the cost to build/replace the 305 with a 305 again is cost prohibitive. I have no clue what the SMMOG rules are UTAH; but here in Texas there is only a Safety Inspection needed for Antique or Classic plates. So, a basic clean running 350 with/or without (your flavor) SMOG/ECM is acceptable.

 

Since you live..."here", I'd KISS and get a Vortec 350. Where are you down south that you need to pass smog? I thought it was only Salt Lake County?

Especially here in UT, you can get 'em all day long from Pick 'n Pull, Tear-a-part, etc., for virtually nothing. They last forever, they're CHEAP, and they're ~250hp -even with the stock, weeny cam. High value. Easy.

 

No SMOG checks in S Utah, SMOG check up north, in Salt Lake City. I just do not want the burden of trying to sell a non smog-able car. Nor an extreme engine swap, the only Restoration Shops, or Race Car Shops, would work on. This to have a more marketable product.

 

Copy. That thing is a Vintage car in UT anyway, so it doesn't need to pass anywhere in UT, and the vintage reg is something like $10. Just an FYI.

If you want to absolutely follow the letter of the smog-law, then you really can't even change the car to a 350, and you "have to" stick with an LG4 305...technically. so how flexible are you, really?
I'd just put in the engine that YOU want, reg is as vintage and go burn some rubber. If it were MY car, I'd drop in that Vortec engine I mentioned above with a smallish cam (210...ish), put it together w/stock-looking parts (painted RPM intake, q-jet carb w/controls in place, change the exhaust but keep a cat, ditch the EGR and enjoy. That'd be stock enough to look stock, and pass a smog test here, and it'd be a fun car to drive.

 

I am flexible on the SMOG issue. Given that all SBC look alike, on the outside, anything with whatever the LG4 had emission wise would work. The OE GM emission decal is missing from the engine compartment. Anyone able to consult a Shop Manual? I believe the LG4 had CCC Carb, EGR, Computer controlled spark advance, maybe a TPS. I am not sure if it had AIR . What say youse? THANK YOU.

 

In that case, you'll have to go w/a non-Vortec long block (or, no vortec heads). To stick to visual, you'd also have to go with pre-'86 heads also...to get the perimeter bolt valve covers.

The LG4 had all of the things you mentioned, including AIR. You could run all of those things on a Vortec long block, except for EGR. The heads don't have provisions for exhaust to run into the intake, to an EGR valve. All of the other stuff would bolt on, work and look OEM, except for the valve covers and the EGR. You could MAKE EGR work with an EGR pipe from one of the exhaust manifolds, but that wouldn't pass visual.

You'll need an '86 or earlier 350. Any '86 or earlier 350 would work, and everything "LG4 emissions wise" would bolt on, work, and look factory.

 

Utah still smogs a car after 38 years? WOW.

 

Yup, it had the full computer control package. Some of it is still visible in your photos; the baro sensor and ESC module for example. Yes it mos def had AIR. You can see at least one plug in a manifold where the lines were. Obviously the Holley carb doesn't accommodate that. It had EGR but that intake doesn't accommodate that. It obviously had A/C which sems to be absent as well.

What's wrong with the motor that's in it? (besides that it has the 305 problem)

 

Nope. UT only smogs in Salt Lake County, and only for vehicles 25 years or newer. He doesn't live in SL county and the car doesn't require any emissions in the state.

Either or both of the above is how/why I am able to have the Kart.

 

So 25 years and done with smog - the same here in Connecticut.

 

My SMOG desires has NOTHING to do with Utah SMOG laws. I want a product I can sell to folks in States with SMOG laws and without. It should at least, appear legit. That way if it fails the sniffer, a Ref MIGHT pass it.

I am familiar with L31 conversions and the EGR issue. I have a good Corvette L98 EGR pipe, that i could make work on the Passenger side exhaust manifold. Would the LG4 CCC ECM (ECU) and a Feedback Rochester "work"? Or would I go with the Scoggin Dickey intake and TPI?

Also, a L98 would be something I would consider.

I would like to know my options, before i buy the TA. I won't know the condition of the existing engine, till after I buy it and do a compression and maybe a leak-down test. It appears to have a "GM Goodwrench 350" I think that might be an old style 2 piece rear main seal and flat tappet cam? Is that correct?

What can you tell me about the viability of an L31 or L98 ? Thanks!

 

First off........don't write off the engine because of fuel in the oil. New intake gaskets and a proper operating carb can fix that. Any early 80's G body, F body, c10 truck, and others with 305 or 350 should have all the smog stuff you need to put back on yours. Find somebody near you that's familiar with these carbed setups and let them put it all back to oe specs.

 

There may not be anything wrong with the engine that's in it, at all.

That appears to be correct, going by the perimeter bolt valve covers.


I don't think that either will pass visual. TPI especially. If you want:
"....a product I can sell to folks in States with SMOG laws and without. It should at least, appear legit."
I'd say that neither option will do ^that^.

 

I'm still not seeing what, if anything, is wrong with the existing engine, to the point it needs a swap.

Fuel in the oil = find and fix the source; virtually always either the mech fuel pump (diaphragm failure: rubber sheet w fuel on one side and crankcase on the other), or leaking/defective carb. Fix whichever it is, change the oil, done. Assuming of course that there hasn't been SO MUCH fuel in the oil for SO LONG that the bearings are toast. In any case, the cause of fuel in the oil IS NOT "the engine"; therefore swapping out "the engine" won't fix it. If you swap the engine without conclusively identifying and fixing the cause of that, you will simply end up with a "new" engine that ALSO has fuel in the oil; butt if you fix the source of the fuel, then voilà! no need for an "engine" swap in the first place.

Seems to me like you need to recognize your priorities and place them in order, then deal with them one at a time. Since this car is going on the market, your priorities should be what THE MARKET wants, not what YOU want. Those appear to differ WIDELY. You are headed down a road of spending YYYYYYUUUUUUUUJJJJJE money on this thing and not increasing its value by A DIME.

Again, I haven't seen ANY indication that "the engine" is "bad" in any way. Translation: don't waste money on changing it out, if the goal is merely to sell it. It's already BEEN "changed"; it even has the nice warm fuzzy GM Sticker Of Surpassing Excellence And Superiority To Aftermarket Crap right on the valve cover for the buyer to see ("See? Brand new factory replacement engine!"). Leave it alone. Quarter car wash it so it doesn't look like it already has a million miles on it and call it good.

First: the kind of buyer that will care if the car is capable of passing smog (I have no idea whether that's "necessary" in your area or whatever other area the car might sell into) will ALSO want functional A/C. Therefore if you don't restore the A/C then it won't matter whether it can pass smog or not. That person isn't going to buy a BO-riddled dusty filthy no-A/C car ANYWAY. Until/unless you restore the A/C, get rid of the BO, deep-clean the whole interior, and otherwise make it "nice" inside, you've ALREADY dialed yourself out of that market.

Second: It's gonna take ALOT of expense and effort to make it "appear legit" re. the smog stuff. I would strongly question the change in value that restoring it would generate. Do some market research and find out NOT ONLY who's gonna be bidding on your car, BUT ALSO what else they can be bidding on and what it goes for (NOT "asking price"; NOT "blue book value"; ACTUAL sale price, and no substitute for it).

Third: you haven't said anything about the overall condition of the car, other than a photo of the exterior. If it needs tires, brakes, a transmission, shocks, etc. etc. etc., the kind of person looking for a smoggable car with A/C isn't going to be interested. How's all that stuff?

I'm guessing you've never bought and tried to sell a car for a profit. That can easily be a humbling and bank-account-draining experience. You're already pointing yourself right down the primrose path to both of those outcomes.

 

Thank you, "Sofakingdom" ! You have been the "Voice of reason" many times on this forum!



Thank you ALL.!

Mike Celi.

 

Error.

 

THANK YOU!