Advice for inspecting an LT4?
Thread Starter
Race Director
Joined: Apr 1999
Posts: 13,002
Likes: 4
From: Paint Hill NC
Advice for inspecting an LT4?
Going to look at one on Craigslist next week if he still has it. Owner says sitting for 2 years, bad gas and bad opti. Says stroked to 383 with head work. I don't know mileage. That's all I know until I go look. How would you guys approach this?
Race Director
Joined: Oct 2005
Posts: 11,772
Likes: 177
From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
But I know some like the "challenge" of bringing a car back to life.
When an owner starts telling you the reasons it won't run (or runs very badly), that is a red flag.
If he says they are easy fixes, then tell him to fix them and call you back.
But that is your call.
As for it being a true LT4 car, just look at the VIN
8th character: 5 = LT4
8th character: P = LT1
A lot of people paint the intake Red and then tell everyone they have an LT4.
If you are good at restoring cars and can get it cheap, it might be worth it.
If you have to pay someone to bring this car back to life, it will turn into a money pit.
Racer
Joined: Mar 2014
Posts: 409
Likes: 7
From: Taunton MA
Solely based on your description above, I wouldn't even bother going to look at it.
But I know some like the "challenge" of bringing a car back to life.
When an owner starts telling you the reasons it won't run (or runs very badly), that is a red flag.
If he says they are easy fixes, then tell him to fix them and call you back.
But that is your call.
As for it being a true LT4 car, just look at the VIN
8th character: 5 = LT4
8th character: P = LT1
A lot of people paint the intake Red and then tell everyone they have an LT4.
If you are good at restoring cars and can get it cheap, it might be worth it.
If you have to pay someone to bring this car back to life, it will turn into a money pit.
But I know some like the "challenge" of bringing a car back to life.
When an owner starts telling you the reasons it won't run (or runs very badly), that is a red flag.
If he says they are easy fixes, then tell him to fix them and call you back.
But that is your call.
As for it being a true LT4 car, just look at the VIN
8th character: 5 = LT4
8th character: P = LT1
A lot of people paint the intake Red and then tell everyone they have an LT4.
If you are good at restoring cars and can get it cheap, it might be worth it.
If you have to pay someone to bring this car back to life, it will turn into a money pit.
I restored an '87. it was a challenge. I am currently restoring a '94 IT SUCKS. Too much "wizzardry" in that car for a shade tree mechanic like myself.
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
I would approach this with caution. Keep one question in mind, "Why would someone sell a stroked LT4 cheap if all it needed was an opti and fresh gas?" Considering they could fix those items and at least double their asking price.
Just about every issue on an LTx car seems to get blamed on the opti. It's also an easy out for a seller to use if they don't want you to hear it run. Get you thinking, it just needs an opti, then you get it running and it has a spun bearing or worse.
I'm sorry, but these cars don't just sit for two years, especially a 383 LT4, because it needs a $300 part. At least not in my world.
Just about every issue on an LTx car seems to get blamed on the opti. It's also an easy out for a seller to use if they don't want you to hear it run. Get you thinking, it just needs an opti, then you get it running and it has a spun bearing or worse.
I'm sorry, but these cars don't just sit for two years, especially a 383 LT4, because it needs a $300 part. At least not in my world.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
As for it being a "383", you can confirm that by looking at the harmonic damper. If the O.D. is smooth and symmetrical, it's probably a 350. If there is a "counter weight" on it, then that would be a 3.75" crank....a "383".
My car was a "sitting for 2 years, no runner" when I bought it....it was CHEAP, and in good cosmetic condition, so I was willing to take the risk. My problems was "wrong key", so in the end, I got a smokin' deal on what has turned out to be a fantastic car. There is a risk there though. Price has to make the risk worth while, and your confidence in your ability to fix it, sufficient.
Thread Starter
Race Director
Joined: Apr 1999
Posts: 13,002
Likes: 4
From: Paint Hill NC
Thanks everyone for the good info.
Price is $5k OBO.
Stroker block is 2 bolt main. Original block has a cracked cylinder.
Dark purple metallic.
Can hear run with starting fluid. Neither of us want to put bad gas through the injectors.
Further advice much appreciated.
Price is $5k OBO.
Stroker block is 2 bolt main. Original block has a cracked cylinder.
Dark purple metallic.
Can hear run with starting fluid. Neither of us want to put bad gas through the injectors.
Further advice much appreciated.
Melting Slicks
Joined: Jan 2009
Posts: 3,482
Likes: 196
From: folsom california
there's a difference between old gas and bad gas. to me "bad" gas would have to be contaminated with water or something else, rust, sand, who knows? Old gas just lost some of it's pep from sitting.
So with that said, hows running it with starting fluid NOT putting "bad" gas through the injectors unless the fuel pump is physically disabled or the fuel line disconected? Inquiring mind want to know.
So it may have been an LT4 at some point...stupid question here..is it a manual and a 96 then it was an LT4..if it was any other year or an automatic, it never was an LT4.
So it definetly des not have the original four bolt main block, that's biggie resale wise . Does it have the original LT4 heads? Pull the oil filler cap, "LT4" should be visible cast into the head.
It sounds like this car was driven and driven hard and then worked on a bunch; the asking price probably reflects its value.
So with that said, hows running it with starting fluid NOT putting "bad" gas through the injectors unless the fuel pump is physically disabled or the fuel line disconected? Inquiring mind want to know.
So it may have been an LT4 at some point...stupid question here..is it a manual and a 96 then it was an LT4..if it was any other year or an automatic, it never was an LT4.
So it definetly des not have the original four bolt main block, that's biggie resale wise . Does it have the original LT4 heads? Pull the oil filler cap, "LT4" should be visible cast into the head.
It sounds like this car was driven and driven hard and then worked on a bunch; the asking price probably reflects its value.
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