'95 RMW Engine Rebuild or Swap?

My wagon has 190,000 miles on it. The engine runs well, uses no oil, but drips worse each year. The Optispark was rebuilt the plug wires replaced at about 160,000 miles. When I drive through a puddle, the engine misfires.

I want to keep the car, but want to use it on long trips, hence need reliability. I've wondered about a LS swap. Can this be done, but still retain the factory options, mainly automatic air? Or is a better plan to rebuild the LT1?

Your comments would be appreciated, especially if you've done this or know of someone who is familiar.

If you have the $ to do the LS swap, that would be my first choice.  Depending on what you want from the car, you could choose and LQ9 truck engine for low end, which is cast iron block with aluminum heads, or you could go for one of the higher rpm, higher torque curve aluminum block lighter vehicle LS engines.  Most important to me would be to get to the better transmissions like a a 6L90e.

A basic rebuild of the LT1 is not all that expensive, especially if you use generic small block Chevy gen  parts.  The only thing that might cost a bit extra is balancing the light crank, which isn't as bad as I thought when I just had it done.  I am doing a higher output, but still low torque version, so it is costing more than minimum, but still not horrible.  Ours at 140K was still running great, and showed little wear inside, but it too was starting to leak too much for me, as I hate leakers.

You will get lots of varied opinions, but what really counts IMO is what you want to do with the car.  Be it make it fast, good cruiser, reliable daily, whatever, all would be different and correct routes to go.

If it runs well, doesn't use oil, but has some leaks and a misfire when wet - I can't see going to all the work/$$ of a rebuild or engine swap?

Fix the leaks, repair whatever is wrong with the ignition system and drive it. 190k miles on an LT1 wouldn't bother me a bit. This isn't the same as the old 350's that were worn out at 100k miles and needed rings, valve job, etc.

Another alternative is a quality stock rebuild like "jasper.com" When contemplating price, make sure you consider all the parts, tools, and supplies you might need for a DIY project.

Most folks who have done complete swaps to new generation power would probably agree the project is always a work in progress that requires more attention and cost than first imagined. A consideration for a project like this is reparability when you are hundreds of miles from home.

As Fix Until Broke posited, your two main issues with your present situation don't seem that bad.

While an LT1 and most other later generation engines do last a lot longer, and good portion of it is the better fuel management that does a better job of not diluting oil, washing cylinder wall, etc, I think. Add in somewhat better oil and it improves a bit again.

I just am finishing up my rebuild, and being overly curious and detailed (engineer) I measured and evaluated essentially every part of the engine as an autopsy type thing. It was still running fine before disassembly. Nearly all the internals were the same parts as in a Gen 1 small block. Same block with minor allowances for reverse flow, same cam with slightly different nose for pin drive and opti, same piston design but light version, rings, rods, bearings, same crank with different balance, heads a hybrid design of fast burn and Vortec I think, same rockers, valves, seals. Only significant difference was the Opti and water pump setups.

This was apparently a well taken care of engine at 135K and was very clean inside. There were worn parts, though, as expected, but they were still functioning well and would have for a while. Cylinder bores were tapered and out of round .002-.003, valve guides nearing high limit for diameter, rod bearings showed odd wear pattern that appeared to be from defective rod big ends being out of round due to manufacturing error, failed pan gasket, valve cover gaskets, exhaust manifold gaskets and out of flat manifolds, intake gasket had been replaced it appeared, timing chain was very loose and worn, head gaskets pretty badly corroded at water holes and would have failed fairly soon plus had some carbon tracking started. Everything else looked quite good. I would guess, with the exception of the head gaskets, the engine would have gone to 200K and beyond, but I was tired of the leaks and at age 71 decided just to do the entire running gear rebuilds for the wagon now while I still can, and then drive until I can't anymore without major issues, I hope. It also gives me a chance to build the, hopefully improved, engine I wanted and change the rear gearing and add a Truetrack. Definitely a good pandemic isolation project for over the Minnesota winter.

Personally, I wouldn't trust a 200K, 25 year old, vehicle for long trips with added on towing besides, unless I had a lot of history of it being able to do it over the years, but I am the cautious type....

I looked for the past couple of years for a replacement for my 93 wagon and I can't count how many I ran across (most were LT1s) that were in the 200000 plus mileage range with no real issues per the seller . . One of my friends has done a couple LS swaps in his shop and the biggest problem he has run into is the electronics and getting all the accessories to work he has used Painless Wiring kits in each swap .If done properly everything should work it's just figuring out those parts of the swap . If it was my car I'd rebuild the current engine or get a replacement as Rev Bob suggested from Jasper or any of the other quality rebuilders out there I think in the long run it will save you a lot of headaches and money .

I would swap an LS into it. The electronic AC is a stand alone, except for the vacuum. The compressor may be located in a different place, but you can have a hose made. You need a radiator that will handle the extra heat from the higher HP engine. An LS does not have a reverse flow coolant system, and a reservoir is needed, but the ignition system is far easier to work on. You should have the computer from the donor, as well as the wiring harness. You can get plug and play harnesses if you can not figure it out yourself. You may not even need to reprogram it if you get the trans from the same car. You need a set of motor mounts for the LS swap. A 6L80 needs a little adjustment to the trans tunnel, and the crossmember needs modification. You should be able to get an engine, trans, wiring harness, and computer for about $1000-1200 from a pic-n-pull yard. The exhaust manifolds, will come with it, but if you want the FEAD, and starter it will be in the higher range. An actual wreck will give you the probability of a good engine. You should pull the driveshaft sliding yoke to make a usable driveshaft, and keep the fluid from running out when removing and installing the trans. I would try to check the mileage, and if you feel it is high, maybe put some new bearing and rings in the engine, and swap in a hotter cam while you are at it. You need an upgraded fuel pump. A Walbro 255 will fit in the same tank sender, and should supply your needs.

If you can turn a wrench, and have some fabricating skills, you should be able to install it with a minimum of help. I installed a BBC in my 91 OCC by myself, including the trans, and aftermarket MPFI from Holley. Installing one with the OEM intake is a lot less daunting, and the LS is a lot smaller than the BBC. The coil per plug ignition is a lot easier to work with as well. It will even fit under your hood with no modifications.

I agree with Fred, but if it were me, I would look for a wreck of a Tahoe, Suburban, or 1500 pickup as the engine and trans programming are going to be closer to the wagon as they are similar weight.  Cars are quite a bit lighter in most cases.  You could probably gear the wagon to match the donor and even more would be right on for the program.

In gearing it, you must also include the tire size.

Fred Kiehl wrote:

In gearing it, you must also include the tire size.

On a truck/SUV swap you might get lucky on that as you might find deeper gears, but taller tires than the wagons and come close to breaking even.

Bocoogto, I hope by asking for comments, you weren’t expecting consensus lol. Ive owned LT1 & LS, no experience with swaps.
It seems from reading here and the ‘other’ b-body site....it seems that successful, completed LS swaps require MANY more labor hours & dollars then initially planned. Fred K, 95wagon and others have done some awesome engine swaps....I don’t think any of them were thinking ‘eh, this will be easier than fixing my LT1’
Fix until Broke (winner of the best screen name ever award) has the right idea. Sort out those minor issues with your existing motor, and enjoy your reliable car. Just my two cents. Im a stranger on the internet....not qualified to give advice

Overcoming the fear of doing the job is the first thing you must do. The task is not that hard if you plan it out. One thing you want to do is have all the possible parts you will need, and that your pocketbook will allow. Plan on taking about 3 months to gather the parts. If you are just installing an engine, and transmission, and not modifying it, it is a lot easier. An LQ4 will have about 325 HP straight out of the box with no major hurtles. The technical stuff has already been done, and all you need to do is copy it. It is not rocket science. Engine freshening is also easy, as long as you label everything, and put it back where you removed it (LS engines need new bolts almost everywhere, because they have torque to yield bolts). There are enough people here on the forum to walk you through it if you have trouble.

BTW, I did not have an LT1 to start with. I started with an LO5. Nobody knows anything about Gen 6 454s, and they do not know the difference between a Mark 1, 2, 3, (there is no Mark 4) or Gen 5 454s, and the Gen 6 454s. You can not randomly throw a dead cat without hitting someone who knows about LS engine swaps.

If you must have the opti replaced, you will be paying for the LS engine. The LS engine can be serviced anywhere in the US, as long as you know what designation it is (LS1, LQ4, etc.). Parts are easy to get, and plentiful.

My favorite type of cat is a dead cat!

actually Fred there is an option to keep the LT1 but get rid of the opti and go to a coil per cylinder type ignition, Torqhead ltd has a full conversion kit that replaces the opti, but it also replaces the PCM with a specially modified plug and play LS series PCM with OBD2. so all you do for the PCM is pull the old LT1 pcm out and theirs plugs directly in, and then just wire the OBD2 plug in place of the OBD1 plug if it's still OBD1

otherwise as some of the other members here I believe have done theres the baileys coil per cylinder conversion, though it retains the optispark, it only uses it for the optical sensor, and not for actual spark.

The Torqhead conversion kit price is half the cost of a Jasper remanufactured LT1 stock engine.

It is a gorgeous piece of engineering, though.

goldwolfnhn wrote:

actually Fred there is an option to keep the LT1 but get rid of the opti and go to a coil per cylinder type ignition, Torqhead ltd has a full conversion kit that replaces the opti, but it also replaces the PCM with a specially modified plug and play LS series PCM with OBD2. so all you do for the PCM is pull the old LT1 pcm out and theirs plugs directly in, and then just wire the OBD2 plug in place of the OBD1 plug if it's still OBD1

otherwise as some of the other members here I believe have done theres the baileys coil per cylinder conversion, though it retains the optispark, it only uses it for the optical sensor, and not for actual spark.

If they give an LS series PCM with it, what happens if you have a custom tune on the vehicle. How do they know how to program everything, by VIN to original spec? Would also obsolete your LT1 tuner.

my understanding is that it's a stock tune for an LT1 but modified for the coil per plug setup, so if your running a tune you'd have to get it redone with this setup.