LT4 questions
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Racer
Joined: Aug 2006
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From: Minnesota
LT4 questions
I'm about to buy a lt4 coupe 96 with 87000 miles on it. It is pretty clean and seems to be taken care of. My questions is there any common problems with this setup with that many miles or is there any to come. Is the longevity of this etup reliable. Anything in particular I should look for before I buy it. I am a car enthusiast and own other cars and am mechnically enclined but looking for some heads up from you guy that know best. Oh, are part availability a problem for the LT4 since it was a one year production?
Race Director
Joined: Sep 2004
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
The LT4 is a stout and reliable motor... however the water pump and the opti are crap in damn near all LTx motors. Make certain those are okay before buying.
Le Mans Master
Joined: Aug 2000
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From: Corona CA
Originally Posted by kwik_ta
The LT4 is a stout and reliable motor... however the water pump and the opti are crap in damn near all LTx motors. Make certain those are okay before buying.
Check and see if they have been replaced yet.
If not you will need to replace it soon.
You just have to decide if its worth it to have an LT4...
Mine's got 106,000 on it and besides clutches from racing the only problem has been the Opti went. I made sure I had the waterpump changed at the same time.
Bench Racer
Joined: Feb 2003
Posts: 4,201
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From: Palm Beach Gardens FL
St. Jude '03 thru 14,'25
Originally Posted by Huntervangolf
Okay like I said I work on my own cars and don't want to sound stupid but what is a opti?
Team Owner
Joined: Jun 2005
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From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Originally Posted by tobijohn
LTx version of a distributor. It's mounted under the water pump so when that goes, the Opti gets drenched and generally needs to be replaced. Needless to say, when cleaning the engine area, keep water away from the optispark...
As to other things going wrong or to look out for, just a few little switches and glitches that'll crop up, nothing major. You may eventually need a clutch (dual mass flywheel is expensive but worth it to me, and to some others who've "experimented" with single mass flywheels). Brakes are supposedly easy, shocks, too.
All weather stripping tends to pull apart, it is expensive and not that easy to replace. Ck it out on the car. That's about it, but others will chime in...
Bench Racer
Joined: Feb 2003
Posts: 4,201
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From: Palm Beach Gardens FL
St. Jude '03 thru 14,'25
Originally Posted by LT4CompYell
Mounted on the FRONT of the engine, I might add...
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Racer
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Even though I just lost my LT4 you can see my thread at the top of general....I changed cams, headers and all of that myself in the car including sensors, water pump, optispark....none of the parts were hard at all to find. Summit has everything you will ever need and basic components (thermostat, sensors, etc etc) can easily be found at a Autozone, Napa, or Advanced. So no problem at all. 
Just dont hit any concrete walls like me...its not pretty.
Just dont hit any concrete walls like me...its not pretty.
Team Owner
Joined: Jun 2005
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From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Originally Posted by tobijohn
:o Whoops, I forgot to mention that little fact. Oh, and about availability of LT4 parts - unlike the LT5, I can't recall anyone grousing about not being able to find them. Have you, Bill?
Race Director
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Originally Posted by Huntervangolf
Okay like I said I work on my own cars and don't want to sound stupid but what is a opti?
Racer
Joined: Sep 2005
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Originally Posted by kwik_ta
Just like everyone said previously... I'll add that the opti generally takes a dump because of moisture. And ironically the opti is mounted behind the water pump which has a stupid history of puking all over the opti. See the chain reaction here? Your best bet is to buy the car and immediately order a Mezierre electric pump and MSD opti from Jegs and you should be golden!!! Ask me how I know
Melting Slicks
Joined: Dec 2004
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From: Howard PA
Don't worry about the opti in a 96, it's an updated version that's a little more water friendly. I've pressure washed my motor a couple of times and it's still OK at 90,000 miles. Same for the WP.
On the other hand I'm probably on borrowed time, it's time to replace it just because we saw some strange peaks on the dyno the other day. This is really nit picking though, I don't feel it, the car runs great. The only thing/person that knows it's old is the dyno.
Except for the heads, cam, crank position sensor, and intake it's basically an LT1.
I did some things to my LT4 but I could have done nothing and I'm sure I'd still be driving it with no trouble. The things I did were things I wanted to do for more performance, not because I HAD to.
Get it, drive it, and don't worry about it until something goes wrong, although I couldn't hurt mine even with high mileage so you should be fine.
On the other hand I'm probably on borrowed time, it's time to replace it just because we saw some strange peaks on the dyno the other day. This is really nit picking though, I don't feel it, the car runs great. The only thing/person that knows it's old is the dyno.
Except for the heads, cam, crank position sensor, and intake it's basically an LT1.
I did some things to my LT4 but I could have done nothing and I'm sure I'd still be driving it with no trouble. The things I did were things I wanted to do for more performance, not because I HAD to.
Get it, drive it, and don't worry about it until something goes wrong, although I couldn't hurt mine even with high mileage so you should be fine.
Last edited by ALLT4; Aug 25, 2006 at 10:00 PM.
Safety Car
Joined: Feb 2004
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From: Minneapolis MN
If this car has been maintained properly and cared for the miles it has on it ain't nothing. If it hasn't been abused or **** pounded it will easily make 200K. What is the sellers asking price?
Race Director
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Originally Posted by Achilleus07
Depends what kind of car this is going to be. If this is his daily driver I wouldnt touch the Meziere Pump...plus you are going to get into the timing chain which is a pain in the butt because the cloyes doubler roller that works on the LT1 will not work on the LT4....trust me when I took my car apart I found out....he could use the heavy duty chain which is what I did...very nice. The generic water pump is just fine. The second edition Optispark that came with the LT4 also has very few problems compared to the earlier model. I had coolant and water...I would say almost a gallon....poor directly on my opti...wiped it off cranked up the car and never a single problem. I havent heard too many complaints from LT4 owners and their opti. Just my opinion.
Race Director
Joined: Dec 2002
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by ALLT4
Don't worry about the opti in a 96, it's an updated version that's a little more water friendly.
With that mileage, if the Optispark was going to go bad, it would have already (and been replaced).
Originally Posted by ALLT4
Except for the heads, cam, crank position sensor, and intake it's basically an LT1.
In fact, about the only common parts are the block and oil pump....and maybe the valve covers.
Larry
code5coupe
Melting Slicks
Joined: Dec 2004
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From: Howard PA
But as far as buying bolt ons, mostly LT1 stuff is the same. Unless you're in the habit of replacing rods, piston rings, and cranks.
If you buy headers, there's no LT4 specific, buy a TB, no LT4 specific, most everything that bolts on to the motor is the same as the LT1.
If you want to dig into the specifics this is a good web page...
http://www.grandsportregistry.com/lt1vslt4.htm
If you buy headers, there's no LT4 specific, buy a TB, no LT4 specific, most everything that bolts on to the motor is the same as the LT1.
If you want to dig into the specifics this is a good web page...
http://www.grandsportregistry.com/lt1vslt4.htm
Thread Starter
Racer
Joined: Aug 2006
Posts: 492
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From: Minnesota
The car seems to be taken care of and not much appearance of a hard life. My biggest concern is if something does go like a cracked head or manifodl or cam that the part is readily available, I mean without having to search bone yards or something. He is asking $16500.00. I can find standard coupes cheaper but like the fact it is a lt4 and should help with future resale. It has the chrome rims on it also. Another question for you guys is what about finding the removeable top? It has the tinted top, can you still buy that new, oem, aftermarket or do you have to look for used ones? Its not bad but has some scuffs and scratches common but would probably replace.
Race Director
Joined: Aug 2003
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From: Lake Mary Florida
I think your worrying for nothing. If it is well maintain and you give it a good check out you'll probably be just fine. Most parts are still available from GM. Transparent roof yes through Melrose T-Tops, they are the authorized GM manufacturer and you can get a lower cost no hardcoat lens or the OEM hardcoated lens.
What the rest of the guy's have said. If you purchase and decide to swap out the opti and water pump remember to replace the bushing (seal) for the water pump drive shaft. That can cause a nasty oil leak with its' tight tolerances.
LTx engines have a tendency to develop an oil leak either at the forward or aft edges of the intake manifold. That is because it is a metal to metal seal and the RTV used tends to break down over time. Also can cause a nasty oil leak. Not a difficult repair take a few hours time.
Between the major Corvette vendors and GM you'll have plenty of parts available. One thing you'll learn as a Vette owner and that is the art of finding parts for the best price. Lot's of good people here to help should you need it.
First item you should buy is the Helm Factory Service Manual. Worth its' weight in gold.
What the rest of the guy's have said. If you purchase and decide to swap out the opti and water pump remember to replace the bushing (seal) for the water pump drive shaft. That can cause a nasty oil leak with its' tight tolerances.
LTx engines have a tendency to develop an oil leak either at the forward or aft edges of the intake manifold. That is because it is a metal to metal seal and the RTV used tends to break down over time. Also can cause a nasty oil leak. Not a difficult repair take a few hours time.
Between the major Corvette vendors and GM you'll have plenty of parts available. One thing you'll learn as a Vette owner and that is the art of finding parts for the best price. Lot's of good people here to help should you need it.
First item you should buy is the Helm Factory Service Manual. Worth its' weight in gold.