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  Topic Review (Newest First)
12-22-2019 05:17 PM
pacey Hi guys been a busy few months after move house , engine is at the shop getting rebuilt and should be ready by next month
heads cam and manifold is all done gone with fast manifold and comp cams 54-428-11 here are some pic of the heads.

now can anyone help me with headers I need some with a 1in 7/8 primary LS1 into 66 impala

05-07-2019 09:02 AM
pacey thanks for the info yes Im using the 4l60e trans and for the tank I have a holley efi tank and holley pan for the LS1 engine
Engine in N/A engine looking for about 430 to 450hp its just a cruise car.
hope the brackets in the above post will work on my Impala. cheers.
05-06-2019 10:20 AM
Deadwolf You will either need a torque converter that is designed for the LS motor (If the 4LE60 came off an LS motor it probably already has this) or you can get a flex plate spacer (not the best option unless you are going as cheap as possible as these will shred apart if you get into it) or you can get the SFI approved LS adapter flex plate.

I'm currently working on shoe horning an LS into a 90 Firebird drag car that will be running a turbo.

Your harness should work, but you will have to look up the harness diagram for the factory car the harness came out of to verify the wires mate up to the transmission. There are also some message boards around that tell you how to modify different factory harnesses for hot rod purposes. You can buy an aftermarket ECU that allows you to tune the car or once you get everything together you can have some with the right equipment dial in your settings and reflash a factory ECU. You will also want to delete the after cat O2 sensors at the same time. As far as accessories go if you got the factory ones out of a car they will most likely fit under the hood of the impala as you have enough room under the hood for a family of 5. The dirty dingo brand of adapter plates are good for motor mounts if you still have your small block mounts, if not get true LS motor mounts that fit the car instead of adapters.

The fuel tank can be modified with a bottom sump and you can use an external fuel up that mounts to the frail rail close to the tank. Also you will need a pressure regulator. They also make aftermarket tanks that fit and look the same as the factory tank, but they have an internal fuel pump and baffling, but you still need the pressure regulator.

Everything I have read says the 1999-2002 LS1 oil pans are the holy grail as far as factory pans that will work in most 60's and 70's chevy's, but the aftermarket pan isn't priced bad compared to finding one of these used ones for sale.

If you ever plan to put some boost to the engine the stock LS can stand about 5-6 PSI of boost no problem. If you want to go higher the rings need to have their gaps opened up a little and then you have people running 14+ PSI of boost. The 5.3 is good to about 800-850 HP with boost using factory connecting rods. Your 6.2 is probably good to about a 1000 HP with the gaps. Granted with a street driven car you don't want to run at the hairy edge like I do for a drag car.
05-05-2019 06:03 AM
pacey hi guys I'm thinking for using this holley kit for the a/c and alt cause I need to move them up on my LS1 swap I'm using a LS1 out of a series 1 GTO 03 model any tip on this kit or has someone used something different.
10-02-2018 09:26 AM
Big Dave Th difference in the crankshaft depth compared to the face of the block is addressed by the flex plate. Order a flex plate for an LS and any automatic will bolt up. If you are using a manual you have to shim the throw out bearing to reach the pressure plate.

Big Dave
10-02-2018 07:18 AM
pacey guys if I was to use a 4le60 trans this should bolt in and plug in to the ls1 loom cause its the same size as the 700r am not look at a big power ls1 only want around 400 to 450hp.
09-16-2018 12:17 AM
BA. Interesting question. You don't see the old tranny used very often with an LS.
The LS motor has a small extension on the end of the crank that may be a problem.
I haven't checked but you might need an equal depth spacer to make that tranny work because of that minor crank protrusion.
I'm not sure how that will play into engagement depth of the convertor but it's worth checking into. Personally I would probably call someone like TCI Transmissions or check their website.

There might be a nugget in here for you as well.

Sent from my XT1254 using Tapatalk
09-15-2018 12:49 PM
Big Dave Don't know if the stock wiring harness will fit (length of wires being either too long or too short), but the ECU will also control a 4L80e. Modern cars have a separate TCU to control the tranny; tying the ECU and the TCU and the three other computers in the car all together controlled by the central computer. This complicates the wiring and you won't need all of the computers that a stock car has (unless you are adding air bags for collision, as well as the anti skid brakes, emission control, and climate control).

Cars I built where minimalised (stock harness disassembled and the extra circuits cut out). I used an aftermarket FAST ECU, and a TCI TCU that was also fully programmable. I cut the the cross-member and boxed it to clear the Camaro oil pan that donated the motor.

Big Dave
09-15-2018 11:31 AM
pacey hi guys been a long time since coming on the forum and now ready to start the getting all the parts ready for the LS swap into my 66 SS
can some tell me if I use an LS3 6.2 can I mount a 4l60e trans to this engine and will the ECU talk to the motor and trans.

and will the loom also work.
12-20-2017 06:51 PM
BA. No doubt there is a lot to consider.

Not knowing if you have any capability of cutting and welding, I wanted to mention that there are some adjustable (fore/aft) motor mounts that may come in really handy for your LS installation. They only move about 2 inches (5.08cm) but they could be valuable instead of cutting into the engine cross-member or modifying an oilpan. (I used the Dirty Dingo brand in an old Camaro and love them)
12-20-2017 05:18 PM
Big Dave You will notice that there is no LS-x into a B-body (Impala car and it's variants):

You will be able to use the Chevelle Kit as a base and find parts as needed to install it into your Impala.

You can not use the Chevelle gas tank (something else that I forgot to include in the motor swap unless you are going to use a carb). EFI requires a high pressure pump to atomize the fuel that is controlled by the engine CPU.

Accessory drive may be useable as is, but I don't don't know what you have as an option (I assume it is similar to the Pontiac G8 sold here in the states). Truck LS has the accessories mounted high over the engine, the Corvette has them all mounted low under the water pump, the Cadillac and Camaro are the Goldilocks (closest to an old muscle car), but there are a lot of parts here in the US that that all interchange on the LS.

Same for the oil pan. GM makes five different oil pans for all of their applications; but none are a direct fit into your Impala body. You will have to either modify your car, or cut and paste parts into the cast aluminum oil pan (easy to do if you can TIG weld), or buy one custom made to fit the older muscle car body which is in the Holley kit.

The transmission cross-member will have to fit your tranny, which may also require a aftermarket flex plate to align everything to align properly.

Holley offers tech support on this product so I would call them for advise on what parts to buy. I used parts out of junk yards here to make the swaps I preformed work: and I relied upon one of my five mechanics who was an LS tunner trained by GM to get it running once I bolted it into the car.

Big Dave
12-20-2017 03:34 PM
pacey Dave am thinking of using a motor out of a chevrolet ss cause we have many in Australia that should work so no one make a custom pan to set 65-70 impala in the states cheers.
12-20-2017 11:16 AM
Big Dave You need an LS-x series engine and wiring harness with a programmable controller, headers, motor mounts, a pan designed to fit older cars (there is no one stock pan that fits though the Cadillac or Camaro can be modified to fit), and a special radiator to handle steam lines (if you have an aluminum radiator a bung can be welded into the tank).

Big Dave
12-20-2017 04:29 AM
LS1 into 66 ss impala

Hi guys just want know whats involved in putting an LS1 into a 66 ss what sump to use headers ,enging mounts ,ect i have a 700r in car already do i need to modify the frame or xmember thanks

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