I have a '96 LT1 with an automatic that will need a replacement engine soon. I'm shocked at how much these used engines are going for if they have less than about 80k miles on them. The only affordable engines, IMO, had well over 100k miles which I think is a waste of time.

There was an LT4 with 66k miles on it that was only a little more than some LT1's with the same mileage. I didn't move on it because I assumed it wouldn't work with an automatic since they only came with manuals. But is that really the case?

Thanks for the info,
Doug

 

I don't know for sure but can not see any reason it would not work

 

the lq9/4 can be obtained very inexpensively and there are many guides to carry out the swap. these will become more and more common.

 

Can't you put your flexplate in place of the flywheel and install it?

I'll bet it's cheaper to rebuild your running engine and start with essentially zero miles.

 

I think it's a reasonable swap. Flex plate would bolt on to the LT4, no problem.

 

Ko1 has a lt4 30k miles for $2,800 here on the forum new castle de

 

Direct bolt in.I would plan on a computer tune and might as well throw a small stall converter in there while the motor is out.

If you want an LT1 look for a camaro/firebird or even an LT1 Caprice for a donor short/long block.

 

Same, but an lt4 is an lt1 with cam and 1.6 rr's. Just rebuild yours.

 

I've been ignoring the 2-bolt LT1's because I assumed the 4-bolt was a necessity. And I've seen many decent 2-bolt LT1's for much more reasonable money. So, do I actually need the 4-bolt LT-1 for the Vette if I'm not doing anything crazy with it like autocrossing?

I'm not always a cheap bastard, but this was just a really cheap Vette to have fun with for a while until we get something nicer (our '76 L-82 is our keeper). And then, hopefully, sell it for about what we paid or more. It has 124k, wasn't maintained all that well by PO's, and we're the 7th owners. So, I'd either spend a decent chuck of change for a big improvement or go cheap for "good enough". This Vette will never be worth much.

I'm also toying with the idea of rebuilding it, but the furthest I've ever gotten into engine repair is when I did the intake manifold gasket a year ago. All of my DIY experience is with brakes, suspension, engine accessories, etc. Nothing internal. I'd also feel more comfortable if I knew exactly what was wrong with the engine. I had a good Vette mechanic take a listen and he agrees with me that it's not a spun rod, but it's definitely coming from deep down in the engine.

For now, I'm just trying to learn what my options are. The cold weather will be here soon enough and I'm in no hurry.

 

There are plenty of 2 bolt blocks out there living a hard life.

My friend had a GTO that sounded like a deep knock and it ended up being the water pump. Not that that is your problem. Are you sure it's internal engine damage? Pulling plug wires one at a time will often lead you to the cylinder at fault. You can diagnose further from there.

if you bought the car cheap and want a good driver, a 2-bolt engine would be fine. After all, they last in f-bodies and caprices as long as you don't beat them to death.

I paid $300 plus shipping from Florida for a Corvette short block with a spun bearing some years ago, so I didn't have to disable my car while building an engine. Your running, knocking motor is worth a decent amount, I'd say.

There are plenty of short track cars out there with 2 bolt mains getting abused weekly.

There is nothing wrong with a 2 bolt.

 

I agree with the others, nothing wrong with a 2 bolt.

The f body and Caprice/Impala/Roadmaster/Fleetwood LT1's are very similar and would work fine. They are 2 bolt and the full size cars have a smaller cam and cast iron heads, but the motors would interchange with yours. I think there were a few differences in the optispark and drive, but if you use your stuff on another shortblock you should be fine.

Some of the full size motors are very cheap. I see complete cars going for $1000 to $1500 and motors for about $500. That would be the cheapest way to get your car running again. If the mod bug bites you, it is a great time to look at upgrading the cam while the motor is out.

If you can do the motor work, it is a good time to freshen it up with new rings and bearings too.

Are you sure you need a new motor? It could be a good chance to try some motor work on yours. It really is not too hard to freshen up a motor with new rings and bearings (and maybe oil pump, timing chain, etc.) Now is a great time to try it if yours is needing it, you already have the big parts.

Good luck.

 

I'm not really sure I need a new motor, but I'm clueless as to the cause of the noise. I had posted a video of the metallic creaking noise to this forum a while back and everyone that replied thought it would be valve train related. When I started investigating the noise with a stethoscope I found that the noise got a good deal louder under the car toward the lower rear portion of the block. But it is not a knocking noise like a spun rod and it's not near the heads. It is a metallic creaking noise that is perfectly in sync with the RPMs.

I took it to a local vette mechanic and he confirmed that is where he hears the noise as well. He went as far as to disconnect the transmission and torque converter from the engine to remove them as possible culprits. In his opinion the noise could be many different things and without tearing down the engine, he can't say what it is for sure. He recommends swapping the engine if I can't/won't rebuild it myself. He doesn't think the car is worth paying someone to do it.

He's also willing to do the swap CHEAP because we used to bring our '76 to him for tons of work before I started learning how to fix the cars myself. He spent several hours diagnosing (including disconnect exhaust to disconnect trans, then reconnect everything) and would only take $100 since he couldn't give me a solid answer!

So, I think a cheap 2-bolt LT1 is probably the best way to go for a car that will never be worth much. The important thing is that the car have a working engine that allows my wife to drive it regularly. She's the one that actually owns the Vette's and she'll sell this for a big loss before she lets a Corvette sit in the garage for too long gathering dust.

Once it's out, I might take a stab at rebuilding the current LT1. If I do, I'm sure I'll end up wanting to mod it as well.

 

IMPORTANT QUESTION: It's probably just wishful thing, but could this cause my noise?

This morning I tried to start the car to move it out of the garage so I could install my new flooring in there. The car wouldn't start. Not even a click. I left it on a charger all day and found other projects to do before going to work the night shift.

I just tried to start the car after over 12 hours on the charger and the 1-year old battery reading 12.5 volts. Again nothing. I tried turning the key off then start a few more times. Then I heard the starter whirring but not engaging the flywheel at all. I got it to spin a few more times after that. Either the starter spins freely or there is complete silence. I would think that is a bad solenoid or bendix.

It's probably unrelated, but...is there a chance that the starter could have been engaged with the motor running all these times since the noise started about 15 starts (and 1 month) ago?

 

back in the 70s when I fooled a lot with small blocks there used to be an unwritten rule that a 2 bolt motor was fine as long as you didn't go over 400hp.

 

Pull the inspection cover and take a look at your flexplate/flywheel. Check the ring gear and check the center where it bolts to the crank and where it bolts to the converter for cracks.

 

A cracked flex plate can sound just like a spun rod bearing.

Next remove and check the starter.

 

I have 370rwhp on a two bolt main that is 13 years old now...no issues at all...original 85 block ...engine has been balanced and blueprinted and has been studded ; eliminated the bolts with studs/nuts....a good engine builder and machine shop will tell you it's a stronger fastener method.