5.3L LM7 Swap
#1
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Car: '85 Z28
Engine: 5.7L
Transmission: 5-Speed
5.3L LM7 Swap
I'm thinking of swapping out my 5.7L in my '85 Z28. It currently has a 5 speed in it, and I'm wondering if the 5.3L LM7 will work with the 5 speed? The 5.3L currently has a automatic trans, will I need to change the computer for it to run right with the 5-speed?
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Re: 5.3L LM7 Swap
Welcome aboard thirdgen.org.
The LM7 is in the LS1 family, so read the LS1 swap sticky, paying particular attention to the part about using a truck engine.
Plan on needing to reprogram the PCM.
If you use the T5, plan on frequent replacement (unless you baby it).
The LM7 is in the LS1 family, so read the LS1 swap sticky, paying particular attention to the part about using a truck engine.
Plan on needing to reprogram the PCM.
If you use the T5, plan on frequent replacement (unless you baby it).
#3
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Car: '85 Z28
Engine: 5.7L
Transmission: 5-Speed
Re: 5.3L LM7 Swap
Thank you very much for the help! I will definetly check out the LS1 swap info. I'm not sure if it's the T-5 that I have, or the T-56. I will have to check on that. Thanks again for your help!
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Car: 1984 Camaro
Engine: LS1
Transmission: T56
Axle/Gears: Ford 9"/4.30
Re: 5.3L LM7 Swap
T56 = 6-speed (six forward gears), not original 3rd Gen equipment.
Unless a previous owner has done a T56 swap, you have a weak T5.
Research, research, research. Its free!
#5
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Re: 5.3L LM7 Swap
A good t5 should last a while behind a stock 5.3 if you don't hammer it. My t5 is holding up just fine behind my high 13 second 350, but I don't speed shift, or do dumb stuff with it. That said, nobody does an lsx swap and leaves the motor stock for long, so plan on upgrading the trans before you upgrade the motor.
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Car: 92 Firebird
Engine: Supercharged 6.0
Transmission: T56
Axle/Gears: 8.8 3.73
Re: 5.3L LM7 Swap
Im curious to see how the T5 would even work behind a LSx engine. You'd have to use a T56 flywheel and PP, but what disk and does the input shaft extend far enough into the pilot bushing? Would the TOB still line up?
Slave cyl would be in the way for exhaust, so youd be stuck with manifolds or custom headers
Slave cyl would be in the way for exhaust, so youd be stuck with manifolds or custom headers
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Car: 86 TA, 91 B4C
Engine: 5.3, 4.8
Transmission: 4L80 4000, T56
Axle/Gears: 4.30 M12, 23.42 10 bolt
Re: 5.3L LM7 Swap
IDK what year LM7s begin and end, but the 2007 up 4.8 and 5.3s all have cranks too long to use a T56, they are .250-.280 too long over a LS1 crank or older GEN III(asides from the 99 LQ4).
But in the case a regular crank did not allow a T5 to work since it was too far out, a newer motor might help the situation as long as it is not a T56.
But in the case a regular crank did not allow a T5 to work since it was too far out, a newer motor might help the situation as long as it is not a T56.
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Car: 92 Firebird
Engine: Supercharged 6.0
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Re: 5.3L LM7 Swap
Where did you read that?
Only oddball cranks Ive seen are FWD LS4's, early iron headed 6.0's and specialty engines i.e. LS7/9
Only oddball cranks Ive seen are FWD LS4's, early iron headed 6.0's and specialty engines i.e. LS7/9
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Car: 1987 IROC
Engine: Turbo 293ci 4.8l
Transmission: T56
Re: 5.3L LM7 Swap
when i was building my rx7 there was a guy that was running a T5 behind a 5.3l he replaced it a couple times and then finally found right/strong enough parts that it stayed together for a while.
actually heres a video of his car
http://www.youtube.com/watch?v=zWYw79L9Q1s
actually heres a video of his car
http://www.youtube.com/watch?v=zWYw79L9Q1s
#10
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Car: 86 TA, 91 B4C
Engine: 5.3, 4.8
Transmission: 4L80 4000, T56
Axle/Gears: 4.30 M12, 23.42 10 bolt
Re: 5.3L LM7 Swap
Nowhere, i just know from experience. All the newer 4.8 and 5.3s i have bought from the junk yard(2007 up) all have cranks that are .270 or something like that longer than the older motors and LS1s, pretty dumb since there are folks that want the GEN IV and cannot run a 6 speed with it.
The flex plate that comes with it is different as well to accommodate the difference.
Hardly had to shim my TH400 with the 08 5.3 in the TA:
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Re: 5.3L LM7 Swap
I have actually been doing a lot of reading on the T5 to 5.3 and it will work. You would need a 621 bellhousing (BBC) and an LS1 clutch/pressure plate/flywheel, an LS7 pilot bearing, and a Howe racing throwout bearing. The transmission will no longer be mounted at the 17* angle and you will need to make a shifter to account for that. There are more and more people doing this, just not in a 3rd gen.
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Re: 5.3L LM7 Swap
I just measured an 08 5.3 and 02 5.7 and the cranks are the same, i noticed a difference in the rear cover that makes it look like the crank hub (where the flywheel/flex plate bolts too), is a little bit longer, but when you remove the rear covers and measure form the #5 main cap on both engines, the end of the crank is about 7/8" on both engines...
#15
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Re: 5.3L LM7 Swap
I have actually been doing a lot of reading on the T5 to 5.3 and it will work. You would need a 621 bellhousing (BBC) and an LS1 clutch/pressure plate/flywheel, an LS7 pilot bearing, and a Howe racing throwout bearing. The transmission will no longer be mounted at the 17* angle and you will need to make a shifter to account for that. There are more and more people doing this, just not in a 3rd gen.
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Car: 1998 Trans/Am, 1989 RS Camaro
Engine: LS1, LQ9 6.0
Transmission: 4L60E, 4L60E
Axle/Gears: 2.73, 2.73
Re: 5.3L LM7 Swap
2002 5.3 lm7 4L60E 2.73 gears stock stall
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Car: 86 IROC / 84 TurboZ
Engine: 5.0 TPI / 2.2 turbo
Transmission: T5 / A413
Re: 5.3L LM7 Swap
I have actually been doing a lot of reading on the T5 to 5.3 and it will work. You would need a 621 bellhousing (BBC) and an LS1 clutch/pressure plate/flywheel, an LS7 pilot bearing, and a Howe racing throwout bearing. The transmission will no longer be mounted at the 17* angle and you will need to make a shifter to account for that. There are more and more people doing this, just not in a 3rd gen.
#18
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Car: '91 TA vert
Engine: turboLSx
Transmission: T56
Axle/Gears: 3.23
Re: 5.3L LM7 Swap
I have actually been doing a lot of reading on the T5 to 5.3 and it will work. You would need a 621 bellhousing (BBC) and an LS1 clutch/pressure plate/flywheel, an LS7 pilot bearing, and a Howe racing throwout bearing. The transmission will no longer be mounted at the 17* angle and you will need to make a shifter to account for that. There are more and more people doing this, just not in a 3rd gen.
#19
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Car: 84 Trans Am, 84 Fiero, 86 944
Engine: 5.0, 2.5, 2.5
Transmission: 5spd
Re: 5.3L LM7 Swap
sub'd to your swap, gonna be doing one myself, but it'll be such slow progress it'll be years before i get it in the car
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Car: 86 IROC / 84 TurboZ
Engine: 5.0 TPI / 2.2 turbo
Transmission: T5 / A413
#21
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Car: '91 TA vert
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Re: 5.3L LM7 Swap
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