LT1 swap help?

[74CustomK20]

Hey all. I'm getting a family vehicle because my daughter is on the way... So figured why not get a suburban!? anyway it needs a motor and I found a guy to trade a my nv3500 for a lt1 out for 95 lt1 motor. The suburban is a 87 year so t had tbi... What will I be poking at for a swap? It has the computer and wiring harness with the motor and the suburban hasn't been hacked up. Any insight? Thanks!!!

[Wgesnerjr]

If you not familiar with them, the Gen II LT1's are special. Basically a Small Block with different heads and intake. Some things I have learned the hard way:

Came in Corvettes, B-Body cars (Caprice, Roadmaster) and F-bodies (Camaro, Firebird) to remove engines: B-Body's can come out from the top like God intended. Satan designed the F-Bodies to come out from the bottom, unless you disassemble the ENTIRE engine first. Vettes look easy but no body in their right mind would ever let me wrenched on one.

Reverse Flow Cooling-designed to cool the heads first, then the block. I have seen some pictures of the cooling path, but to this day, I cannot comprehend it. Kinda like a Mopar torsion bar suspension. Just does not compute!

Heads-Aluminum on Vettes & F-Bodys got a little more HP, Iron on Caprices, Roadmasters, cops let them idle for days with no worry. Known for broken exhaust manifold bolts. Google it and wonder why GM uses torque-to-yield fasteners.

Intake-Has NO coolant flowing through it so no water leaks. Oil, however, seems to leak on regular intervals. Check the owner's manual, they may be part of the regular maintenance schedule. Gaskets are not a bad job in the B-bodies. Sucks in a major way on the F-bodies as the windshield comes half way over the engine. Mentally prepare for this. Throttle body blades like to coke up and stick. Buy lots of spray cleaner.

Water pump-another one of Satan's designs. driven off of the cam, there is no side load-so no bearing wear. But the steel drive connector will strip out and leave you and your wife stranded on the highway in 103 degree heat...while you wait for the AAA tow truck, decide on a visitation schedule for the kids. No matter how much you drain the system to replace it, there is always some that will pour down on the distributor.

Distributor-Optispark, Yes, having way more faith in the water pump then they should have, the design team moved it UNDER the water pump for packaging purposes. It sometimes gets a bad rap. Driven by a cam through the front timing cover. Early units were unvented and tended to fill with moisture and fail. later vented ones can be reliable as long as the water never needs to be removed. My T/A has 127,000 miles on it. It has even run when the front cover seal failed and it filled with oil. Cleaned it out and still going. Still an idiotic place for electronics.

Front timing cover-has three holes in it for the crank, water pump and the optispark. this is also three more places to leak oil. There are special tools to put these seals in, some have used a Sharpie body with some success. I bought the tool once my kid realized I was stealing her markers.

Plug wires-almost impossible to route without extensive removal of front drive. F-bodies are a little better since they run around the accessories. B-bodys go BEHIND the power steering pump. Have metric crow's foot wrench on hand and prepare for a Exxon Valdez sized mess. My garage is now an EPA Superfund site.

PCM-reliable and reflashable. Tuner-cat has the software but it is NOT windows based. If you failed MS-DOS in college, keep your sanity and pay someone to do it for you.

Thermostat - Just know it's different. do NOT try to use a regular SBC one to save some coin. If you do, it will overheat and again, strand you and your wife on the side of the road. Good thing is it gives you time to divide up your assets while you wait for your new friend and roommate, the AAA tow truck driver.

Performance - Mostly reliable with the above exceptions. good power and great torque. Not many mods out there and what is available, has an extremely unfavorable horsepower to cost ratio. Years ago I worked at YearOne and watched as the execs dumped tons of mods for little results. even after LT4 kits, cams, CAI, headers, exhaust and PCM programing, best they got was a couple of 100 HP for many thousands of dollars. Ultimately, if you want gobs of power, your have two choices: A. forced induction or B. LS swap.

I tended to beat up on them but their really good engines and still go like stink! (yeah, I own 2 of them. T/A and Caprice wagon with 215K) Given me plenty of smiles per mile. Not many places stock parts for them as they were made for only a few years. I can see that this was GM's last hoorah for the SBC. They really did all they could without a major design change. The LS successor is way better in power and cost, so you may want to think about that before jumping on this swap.

Good luck.

[Tom]

Dam....that was great.
Like I think[?] he said above, it's not worth the swapping hassle.

[74CustomK20]

I would go for an ls swap but I can't afford it. Since I csnctrsde for this I'm hoping to just keep costs low by new gaskets and minimal surprises. Thank you Jay that was a TON, literally, of info lol. I'm trying to keep costs down to try n save money, so not really buying any new parts of possible. I was mostly curious of the... Wiring aspects I guess... Or how any of that works... All this thinking is hurting my head...

[Tom]

Do you need an engine, or are you looking for power? Sell the LT1 and buy some stuff for the original 350.

[Nickelcharlie]

Jay thank you for a very informative post. I was very interested in what you had to say because am looking at dropping an LT1 engine in my 86 for 3 reasons. 1. To get away from the carb. 2. An inexpensive swap with all the power that I would need. 3. I think it would be a good looking swap in a square body truck! I was glad to see you have 215 thousand smile miles on one of your engines.
I have several friends that Auto cross their C4s and one said that he has never seen a break down due to an engine problem. He has one C4 that he Auto Crosses and he runs the crap out of it!
Near me is a wrecking yard that only deals in C4s. He will sell me a complete LT1 with all the wiring that I need to get it running for 900.00. The last time I question an Ls swap the engine was close to 2500.00 to 3000.00. I am guessing that price has come down some because the abundance of Ls engines ou there for sale. Anyone have some prices of an Ls engine?
The owner of the wrecking yard mentioned how how easy this swap would be! He told me that it will mount up to the stock truck motor mounts. He said an engine from a Corvette with all the accessories on the front of the engine will drop in without touching the frame where as an LT1 engine from other cars the accessories will interfere with the frame because they are spead out more.
One thing I don't like about the Ls engines is they all have piston slap until they warm up then it goes away. Still a great engine.
I hope more people will add to this post so all information is presented. Jay did a great post.

[74CustomK20]

Whichever will be best for a daily driven suburban I guess. I'm just looking for what will give me the most power and fuel milage, providing I have both motors. The lt1 will get new gaskets and inspected but the traditional small block has bad valve seals and will need a different intake for the tbi. I have both. And I am capable mechanically of doing either one. Just the Wiring is NOT my strong point

[74CustomK20]

I agree. I'm just trying to see which would be better for my application providing I have both in front of me.

[andrewmp6]

http://www.hotrodlane.cc/PDFFILES/83chevyLT1install.pdf

[Nickelcharlie]

Thank you andrewmp6, great post!

[74CustomK20]

Agreed that has a lot of info. Just for S&G here is the motor. I have a guy interested in the 350 and my spare chassis so hopefully it'll be gone soon... I plan on keeping all my accessories off the old 350 and steering components so I can compare and figure something out in that aspect. My pump is literally brand new along with my alternator. I will keep this updated as I tear apart the lt1. Maybe others will learn from my mistakes lol

Edit wth is a security token???

[74CustomK20]

More updates. Removed the Wiring from the motor and exhaust manifolds. Will be replaced with headers and also pulled a.c. won't be reinstalling that. So far all looks good. Found the dizzy too lol it is way way hidden under there. I'll keep posting and will try to upload pics.

[Katrina/10]

I hope you never have any trouble with that Opti-Spark, those things are a pain to change and not cheap.

[74CustomK20]

I shouldn't, and hope I don't. I'm going to keep tearing it down this weekend and then clean then hell out of it.

[lilpoindexter]

I had a 95 caprice wagon. I thought the LT1 was a good ballsy engine, with decent economy...but it has a bunch of unique quirks. I wouldn't build one today.

[74CustomK20]

Not really building it just a gasket kit and anything that needs replacing I'll replace it. I have the passenger side apart and about 75% of the front accessories off. Its different but the info posted above has helped a ton. Side note does anyone know what this is? Its on the driver side front about half way down. Just a big black box with rubber grommets around the bolts... and just says in and out... Any info? Needed or nah?

[Wgesnerjr]

Air Pump. It was used for emissions, but has since been discontinued because it's not needed anymore. Actually will raise emissions if you left it on and working. I've removed all mine and all the piping that goes over to the exhaust manifold. Ironically Durango oil drain plugs will plug up your exhaust manifold ports and you can eliminate the whole system. Looks much cleaner too!

[74CustomK20]

Awesome! That is what I like to hear. I planned on eliminating as much as possible for easier swap and also better performance. I'm keeping all I pull off though in case it is needed. Suburban is "supposed" to be here tomorrow so will post pics too!!!

[jayoldschool]

You need the AC delete pulley if you're not running the compressor. There is no "short belt" solution on LT1s.

[74CustomK20]

I'll remember that Jay. If I can't afford it I'll just put it back on and run a normal belt until I can afford it.

[74CustomK20]

Also how important is the oil cooler? My goals also in this swap is to remove as much as possible. Like ac, oiler cooler if possible egr b.s.... Air pump etc etc.

[74CustomK20]

Bad news all around. I pulled the intake off and the cam is pretty ate up and so are the bearings. I don't have the money to replace them or the 300+ to get it ready to put in the suburban. I'll have to use my 77 4 bolt main motor for now until I can get the money saved up. By the time I get it might be better off ls though...

[Wgesnerjr]

Probably a better idea. The LT was a great motor but just not worth the $$$ needed rebuild and the sweat and aggravation to install. I was going to suggest you do a price comparo between regular SBC parts and LT specific parts (Heads, Intake, Waterpump, etc) and let that be your guide. But the Chevy gods have decided for you.

Just as a side note, I got my 5.3 LS complete with Engine, Trans, Wiring, Under hood fuse box, PCM, Throttle pedal, front drive and manifolds for $1400. It can be done cheaply, just have to watch the costs.

[74CustomK20]

Maybe I'll do that long term. My daughter is due the 105th so I'm trying to hit this as hard as I can to fix it and get the suburban up and running. It's a tbi originally so maybe it'll scavenge up mid teens far as mpg. One can hope right?

[74CustomK20]

Update even though the lt1 idea is done pretty much. I'm going to take my 77 010 block and put on a set of 94 head's intake and tbi unit. From all I read tbi pretty much stayed the same from 87-95 so should be fine. Plus gives me a chance to open up my motor and inspect. Maybe help it out a little... Anyone confirm that 94 parts are the same? If so I'll just need a. flexplate for the 700r4 and a dizzy... Much cheaper than redoing the lt1 lol