Is the LT1 reliable?
Thread Starter
Drifting
Joined: Jan 2006
Posts: 1,372
Likes: 2
From: Ramona CA
Is the LT1 reliable?
I'm new to the LT1 community. My C5 has an LS1, very reliable. My '84 had an L83 with Crossfire. Very reliable, funcky looking induction setup but very reliable.
The previous owner put a ton of money into this car getting it repaired. I think some of was the shop ripping him off. A reply to one of my other posts talked about all the things he changed on his LT1 C4. Leads me back to my question, are these LT1 engines reliable? Anything to look out for? From the tranny back it's basically the same car as my '84 Vette.
The previous owner put a ton of money into this car getting it repaired. I think some of was the shop ripping him off. A reply to one of my other posts talked about all the things he changed on his LT1 C4. Leads me back to my question, are these LT1 engines reliable? Anything to look out for? From the tranny back it's basically the same car as my '84 Vette.
Thread Starter
Drifting
Joined: Jan 2006
Posts: 1,372
Likes: 2
From: Ramona CA
The engine has 176K. Opti-spark, radiator, hoses, water pump, rear main seal, injectors, ecm, ASR. Just to name a few things. It uses synthetic oil (10w30). One of the reasons I bought it is he replaced all of these things.
Melting Slicks
Joined: Feb 2008
Posts: 3,286
Likes: 6
From: Palm Beach
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
Le Mans Master
Joined: May 2005
Posts: 7,359
Likes: 2,281
From: Central Maryland
Very reliable. The only potentially weak component is the distributor (aka Optispark or just "opti"), but don't let it scare you. It's a distributor, nothing more, nothing less, albeit an advanced one (no pun intended). The chief problem with the Opti is its placement under/behind the water pump. This makes it somewhat vulnerable to getting a coolant bath, which will nearly always kill it, and also makes it somewhat more challenging to service, as quite a few items need to be removed to gain access to the unit.
There are many LT1s out there that have gone a lot of trouble-free miles.
Live well,
SJW
There are many LT1s out there that have gone a lot of trouble-free miles.
Live well,
SJW
Le Mans Master
Joined: Jun 2009
Posts: 6,528
Likes: 752
From: South Dakota
I have had 2 Corvettes, 3 Impalas, and 1 Z28 with LT1's.
I never had any problems with them except I had to do a water pump in the Z28. I have 128k on my current 94 Corvette and have had about the same on a couple of Impalas.
My experience is that they are very good and reliable motors.
I never had any problems with them except I had to do a water pump in the Z28. I have 128k on my current 94 Corvette and have had about the same on a couple of Impalas.
My experience is that they are very good and reliable motors.
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Race Director
Joined: Jan 2005
Posts: 10,641
Likes: 13
From: Slidell Louisiana
Had more than 150K on my Impala SS....and it was running fine when Insurance company totaled it due to some rear end damage.. God I loved that car....
I drive my 1995 C4 all over...sometimes more than 1,000 miles in a day (I love road trips).
I drive my 1995 C4 all over...sometimes more than 1,000 miles in a day (I love road trips).
Melting Slicks
Joined: Aug 2007
Posts: 2,619
Likes: 1
From: Salem Oregon
St. Jude Donor '09-'10-'11
I have over 150,000 on mine and counting.
I recently had similar work done on mine as it developed an oil leak that we couldnt locate, so I took it to a highly respected Corvette mechanic here locally who also happens to be a member of the forum.
He replaced all my gaskets, as well as I had him put in a new opti because the water pump had to be replaced anyway, as well as new plugs and wires, new pulleys, a fuel filter and a 160 degree thermostat as it was running extremely hot.
The water pump that I had just purchased turned out to be a faulty one.
It runs like a top now, and plenty of power left.
I recently had similar work done on mine as it developed an oil leak that we couldnt locate, so I took it to a highly respected Corvette mechanic here locally who also happens to be a member of the forum.
He replaced all my gaskets, as well as I had him put in a new opti because the water pump had to be replaced anyway, as well as new plugs and wires, new pulleys, a fuel filter and a 160 degree thermostat as it was running extremely hot.
The water pump that I had just purchased turned out to be a faulty one.
It runs like a top now, and plenty of power left.
Team Owner
Joined: Aug 2005
Posts: 34,988
Likes: 515
From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
I'm on my third LT engine.
...YES
11 seconds of LT1 reliability proof.
...YES
11 seconds of LT1 reliability proof.
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
Some of us have as much as 200,000 to 300,000 miles...is that reliable?
I only have 180,000. Its a matter of maintenance and not what type of was used.
This LT1 has got me to work every day for the last seven years.....25 miles each way...rain or shine.
I only have 180,000. Its a matter of maintenance and not what type of was used.
This LT1 has got me to work every day for the last seven years.....25 miles each way...rain or shine.
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
Cruise-In IV Veteran
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Cruise-In VIII Veteran
Heck yeah! Mine's only flatbedded me once in 10 years and 120,000 miles of ownership. And that was due to a coil that was left installed wayyyyyyy past its maximum service life (my fault).
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
Cruise-In IV Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
Cruise-In VIII Veteran
Even in stock form, my LT1's surprised many a **** thinkin' it was just a "lowly C4." The first time mine got rubber from a WOT kick-down at 60 mph, (A-4 auto) it actually surprised me, too. 
Racer
Joined: Feb 2005
Posts: 278
Likes: 4
From: Havre de Grace, Maryland
Overall, LT1s are very reliable, with one word of caution. I had over 40K track miles on mine before it blew. High rpm, chop throttle and a tight turn killed it. It probably would have lasted much longer if I had a road race oil pan and accusump... lesson learned. If you plan to track the car, get rid of the stock pan for a baffled road-race pan (Canton or similar) at a minimum.
