LT1 Engine Swap?

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08Malibu

Royal Smart Person
Feb 9, 2014
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The most simple upgrade is a gen 1 small block. Because its carbed so the swap is pull it out and drop it in. Everything will bolt right up. The only thing is to use a later motor something from 86 on up because of the one piece reaf seal block. You can use your flex plate that bolts to the converter just as it is. Any 350s will be a good upgrade. My choice would be a later 96-2000 vortec truck motor. Roller cam and the best heads GM made. These motor have so little whear in the cylinder you can just hone and rering and new rods mains and mabe cam bearings. You can up the cam with a mild upgrade (something under .480 lift and still use the stock springs. Only thing you need is a new or used intake ($150 or find a used one) and reuse your HEI and carb if you want. If you want to use the stock hyd roller cam then just put a set of 1.6 rockers to give it a little more lift and enjoy.
It’s funny you say that about the cylinders. I pulled the heads off of my engine that has 176k on it, and there’s zero ridge.
 
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Oct 14, 2008
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As said, these motors were quick in the Camaro and Firebird. My BIL had a 95 Z28. Of course the 4L60E died with under 200,000 Km. He had a tick, took it in just under the used car warranty at the GM dealer. He made them adjust valves since the tech let it slip that this car had the oil pump pickup fall off, supposedly not the only one it happened to. My BIL is a Technician and not a pushover, he was not pleased. He had no issues with the Optispark that I remember. Yeah, I forgot about the PWM converters, trucks got them too, which some claim give issues once they get some miles on them. It will be massively more powerful, just make sure you don't have 2.14 rear gears, way too tall with a .70 overdrive gear. Good luck.
 
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Built6spdMCSS

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Jun 15, 2012
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PWM is pretty much every transmission since 1995, can disable it in the 4L80E. It's a solenoid in the valve body that eases into lockup, and some don't lock up 100%.

So the LT1.. 1995-up OPTI Spark design is vacuum vented, works much better. Replace factory Ignition Control Module & Coil with the MSD Blaster Coil. Do your Throttle Body Bypass. Delete the EGR and install the block-off plates. 1996-97 models had a 4x reluctor on the crank with a crank sensor. 1995 is a one year only thing, first year of PWM but still OBD1.

Will bolt directly in given it's Gen II SBC.

Fuel system needs to be setup for EFI that puts atleast 42# at the rails.

Wiring wise for EFI, damn near identical to the LS Engine.

As mentioned, finding someone to tune the LT1.
 
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Supercharged111

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Oct 25, 2019
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Tuning the LT1 is easy if you're into that stuff. A 411 can be pinned in and just like that you have all the tunability of an LS motor. TCC PWM can be mechanically disabled by pinning that sucker wide open. I think the last one I did I either moved a spring or flipped the valve itself around and it was physically unable to move, just provide full instant lockup. Felt like a 700R4 locking up, no harshness whatsoever. Can also do it via the tune.
 

Built6spdMCSS

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I know the crank sensor in the 0411 is the base input for spark. Makes me wonder if you pinned it all in, didn't hook up the coils, disabled all the codes for that since the LT1 has the OPTI Spark, if it would fire injectors.

There's that little connector on the OPTI too..
 

Supercharged111

Comic Book Super Hero
Oct 25, 2019
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I know the crank sensor in the 0411 is the base input for spark. Makes me wonder if you pinned it all in, didn't hook up the coils, disabled all the codes for that since the LT1 has the OPTI Spark, if it would fire injectors.

There's that little connector on the OPTI too..

You just use the 96-97 4X crank reluctor with a 350 Vortec van tune. Optical sensor is ignored, car runs in batch fire mode, and opti stays as a distributor only (no coils near plugs, unless you want to pony up for a 24x swap in addition). If this is someone's first EFI swap though, it may be a bit much for them.
 

czbill

Not-quite-so-new-guy
Mar 4, 2023
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First, thanks for the add. It's been a while since I had a GM, last was my 2000 Silverado. I recently bought a 1986 El Camino, nice car, totally rust free, nice paint decent interior. It has the 305, auto. It runs ok, but getting up to speed to merge on the freeway isn't easy sometimes.

I have a chance to pick up a 1996 LT-1 and transmission from a Caprice I believe. About 105,000 miles. Would this be good for a swap for the 305 in my 1986 El Camino? The guy wrecked the car, the motor and transmission look clean, he supposedly really took care of the car. I was also thinking of the difficulty of finding an ECU and transmission controller. My car is carbureted, so I would need to change the fuel pump/tank or buy an intake manifold and carburetor.

Would an older small block or a newer LS be better/easier? Looking for a cruiser with some power, not a race car.

Thanks.
Wow, what a lot of good information is out there, thank you.

Here are some pics of the engine, it doesn't look to me like the Google photos of the LT-1, was it modified? It has aluminum heads. It doesn't look like the water pump is cam driven. Apparently the car was wrecked 6 years ago and my friend saved the engine and transmission just as car was being hauled to the scrap yard. It was crushed, no ECU, no wiring harness.

My present thought is to see if an HEI distributor can be fitted where it used to be on older small blocks? Maybe with a carbureted intake manifold and an older style cam that would have the drive gear? I am not sure what transmission it has. I expected a 4L60e transmission, I don't think that is what is there, and I'm not sure it will fit in the drive tunnel of the El Camino. I couldn't find any electrical connections on the transmission either. Looking for more guidance. Thanks.
 

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Built6spdMCSS

Geezer
Jun 15, 2012
5,692
9,500
113
Florida Beach
Wow, what a lot of good information is out there, thank you.

Here are some pics of the engine, it doesn't look to me like the Google photos of the LT-1, was it modified? It has aluminum heads. It doesn't look like the water pump is cam driven. Apparently the car was wrecked 6 years ago and my friend saved the engine and transmission just as car was being hauled to the scrap yard. It was crushed, no ECU, no wiring harness.

My present thought is to see if an HEI distributor can be fitted where it used to be on older small blocks? Maybe with a carbureted intake manifold and an older style cam that would have the drive gear? I am not sure what transmission it has. I expected a 4L60e transmission, I don't think that is what is there, and I'm not sure it will fit in the drive tunnel of the El Camino. I couldn't find any electrical connections on the transmission either. Looking for more guidance. Thanks.
That's a newer 5.7l Hemi....Mopar. ;)
 
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