8x Series V8 Swaps (4 Viewers)

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Yes, no problems with a swap in your truck.

There is no one itemized list, there are so many variables with an LS/Vortec based swap that a full list is impossible. You have to narrow down your specific drive line before even a partial list is possible.

Everything you need to know is available here on MUD and other internet sites. DO NOT limit your searches to LC specific sites. Some guy in Idaho with a 69 Camaro had the same issue you do to overcome and detailed how he did it on a Camaro forum somewhere.

I have done multiple swaps and I can tell you that no two have been the same yet. Example: GM makes changes in harnesses, throttle bodies, water pumps, PS pumps, exhaust manifolds, intake manifolds, fuel line arrangements etc etc etc. All the time!

At one point they were selling LS3 C&C packages but were not selling the front drive assembly for that specific motor because they had PS pump supply issues. Consumer was left to go to an older front drive assembly and make it work. I had a 5.3L Vortec crate motor that their part# starter would not bolt up. GM Performance had no clue about it. The guys at Summit Racing did and had the right starter on my door the next day! Free! With a return ticket on the wrong starter.

Best advice I have is to write it all down on paper and start filling in the blanks. Do not cheap out on cooling and wiring. Good luck with your swap :)
 
I think its 16x1.5. I believe Mark's 4wd has a adapterfor it.

No, it's definitely not M16x1.5, because it almost fits into the M12x1.5 hole in the head. I got a 1/4" BSPP adaptor, but that's not it either.

temp_sensors2.jpg


I think I can just use another GM sensor though. My son and I did a little experiment last night - measured the resistance of the GM sensor and the Toyota sensor in bowl of ice water, and a pot of boiling water.

temp_sensor1.png


The slope of the response is alot different for the two sensors, but the reading is pretty similar in the area we're interested in:
Note that water boils at about 198F at my altitude.

temp_sensor2.png


So I'm thinking that the gauge may read a little lower then we're used to at typical operating temps of 190F to 195F. But should be about the same when things start heating up to the 200F range. And the factory gauge with the GM sensor should actually read higher sooner if the temp keeps going up - not a bad thing considering the poor responsiveness of the factory configuration.

I'll keep an eye on it with an OBD2 reader until I'm comfortable with it. If it doesn't work, I'll look at adapting the Toyota sensor some more.
 
Working on this one now. Wiring & shifter linkage are the only things that haven’t been ironed out.

View attachment 1954223
That looks nice in there... What year and size is that motor? when did you finish it? Maybe post some more pics.
 
That looks nice in there... What year and size is that motor? when did you finish it? Maybe post some more pics.

Thanks! That is a 6.2L LS3 crate motor, with the Connect & Cruise 4L65E package. It was finished earlier this year. Here it is all together:


01476C75-1720-4B37-9F42-803167FFFFFF.jpeg
 
Thanks! That is a 6.2L LS3 crate motor, with the Connect & Cruise 4L65E package. It was finished earlier this year. Here it is all together:


01476C75-1720-4B37-9F42-803167FFFFFF.jpeg
What year is it?
Who did the swap? Who made your harness?
Thanks
 
What year is it?
Who did the swap? Who made your harness?
Thanks

-‘94 LC, new LS3 (2018)

-I did the swap, for a customer

-The harness is part of the GM Connect & Cruise Package. I also use (and have a good working relationship with) Howell harnesses. I would probably use one of theirs over the C&C next time.
 
No, it's definitely not M16x1.5, because it almost fits into the M12x1.5 hole in the head. I got a 1/4" BSPP adaptor, but that's not it either.

View attachment 2139587

I think I can just use another GM sensor though. My son and I did a little experiment last night - measured the resistance of the GM sensor and the Toyota sensor in bowl of ice water, and a pot of boiling water.

View attachment 2139575

The slope of the response is alot different for the two sensors, but the reading is pretty similar in the area we're interested in:
Note that water boils at about 198F at my altitude.

View attachment 2139576

So I'm thinking that the gauge may read a little lower then we're used to at typical operating temps of 190F to 195F. But should be about the same when things start heating up to the 200F range. And the factory gauge with the GM sensor should actually read higher sooner if the temp keeps going up - not a bad thing considering the poor responsiveness of the factory configuration.

I'll keep an eye on it with an OBD2 reader until I'm comfortable with it. If it doesn't work, I'll look at adapting the Toyota sensor some more.
Sorry that I was incorrect on the thread size.
 
Thanks! That is a 6.2L LS3 crate motor, with the Connect & Cruise 4L65E package. It was finished earlier this year. Here it is all together:


01476C75-1720-4B37-9F42-803167FFFFFF.jpeg

That's a really clean intake - can you tell me what you used?
 
That's a really clean intake - can you tell me what you used?

Thanks, it was a 4” 150 or 180 degree bend cut to fit.
 
I continue finetuning the small details, they seem endless, truck runs and drives great, im just tackling minor stuff.

Does anyone wants to share how they dealt with the Oil Warning light? Seems GM sensor sends a (-) signal when oil is low, and Toyota measures resistance? Any insight on how to wire this would be appreciated, Im tired of seeing my oil bulb light all the time.

IMG_6454.jpg


Thanks.
-Emerson
 
Question on the LS swap. I am putting one in my BJ73 and worried about the space next to the frame with the AC compressor is located on the GM LS truck. Does the A/C compressor fit in the stock location on an 80? how much room is there to the frame? I think the 70 series frame is a couple inches narrower than an 80....
 
Question on the LS swap. I am putting one in my BJ73 and worried about the space next to the frame with the AC compressor is located on the GM LS truck. Does the A/C compressor fit in the stock location on an 80? how much room is there to the frame? I think the 70 series frame is a couple inches narrower than an 80....

Whats the inside-rail width of a 70 frame?
 
Question on the LS swap. I am putting one in my BJ73 and worried about the space next to the frame with the AC compressor is located on the GM LS truck. Does the A/C compressor fit in the stock location on an 80? how much room is there to the frame? I think the 70 series frame is a couple inches narrower than an 80....
i have 5.3 from 2007 and i set my engine so there is 1" space on a/c side and 1" on power steering pump side
 
FYI, the 73 series measured 1" narrower than an 80 frame.
 
FYI, the 73 series measured 1" narrower than an 80 frame.

Look into a TC or CBR steering pump and modifying it to work with a remote reservoir. It will stick out less then the regular GM reservoir P-pumps and you’ll be able to move the motor more to the drivers side. It will gain you maybe 1/2”-1”, and they’re better pumps.
I’ll have a write up for this hopefully before the end of the month.
 
I continue finetuning the small details, they seem endless, truck runs and drives great, im just tackling minor stuff.

Does anyone wants to share how they dealt with the Oil Warning light? Seems GM sensor sends a (-) signal when oil is low, and Toyota measures resistance? Any insight on how to wire this would be appreciated, Im tired of seeing my oil bulb light all the time.

View attachment 2147609

Thanks.
-Emerson
@tmxmotorsports can probably help yah out..
 
I'm in the middle of my 5.3/4l60e swap and I'm having second thoughts about the long term reliability of the 4l60e. If I end up gernading a 4l60e or 2 is it possible to swap over to a 4l80e without changes to the marks adapter housing? I believe the # of is splines is different between the two transmissions so I would need a different transfer case input shaft.

The reason I bring this up now is because I'm about to order the 4l60e -> HF2A adapter and I don't want to spend $1500 only to change transmissions and spend another $1500 on 80e adapters...
 
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I'm in the middle of my 5.3/4l60e swap and I'm having second thoughts about the long term reliability of the 4l60e. If I end up gernading a 4l60e or 2 is it possible to swap over to a 4l80e without changes to the marks adapter housing? I believe the # of is splines is different between the two transmissions so I would need a different transfer case input shaft.

The reason I bring this up now is because I'm about to order the 4l60e -> HF2A adapter and I don't want to spend $1500 only to change transmissions and spend another $1500 on 80e adapters...
Put in a built 4l60?
 

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