LSX G-body Swap Write Up

Westbank of NOLA

Westbank of NOLA

Not-quite-so-new-guy
Oct 31, 2014
49
8
New Orleans
So, I have to ask. After reading the list of wires that need to be deleted from the harness for EFI on the swap (LT1 swap . com). Whats the opinion on running a carb? Also, what would need to be done wiring and computer wise?
 
jacobdavis1979

jacobdavis1979

G-Body Guru
Feb 18, 2011
707
18
Im running a carb on mine. You would need the msd box and intake. But if you got the stuff to go injected thats the way to go
 
8

85GPLef41

Royal Smart Person
Nov 14, 2008
2,225
63
Colorado
I would keep it EFI ..... nothing better then jumping in priming the fuel pump and it starting right up every single time! Now I've read that the carb conversion only makes a few more ponies then the efi IN racing applications... :mrgreen: but IMO the ecm is very potent in making HP as well along with the the conveniences of a modern engine.. If I could get away with it would have made my life much easier!
 
O

onesickGSX

Not-quite-so-new-guy
Apr 10, 2014
34
6
PA
Westbank of NOLA said:
So, I have to ask. After reading the list of wires that need to be deleted from the harness for EFI on the swap (LT1 swap . com). Whats the opinion on running a carb? Also, what would need to be done wiring and computer wise?
Well after thinning the harness, wiring a few relays, a few fuses, and laying it out the way you want then wrapping it with electrical tape and wire loom. The only thing you have to provided from the car is a few 12v hot and 12v keyed electrical sources. Aside from that it depends on what you want. If your using a 4l60e or 4l80e you will need to run an electric speedo gauge, if not you'll need to fab a kick down cable, also a check engine light and a brake switch signal will need to run to the ECM. Honestly if you plan to keep the engine stock at first your best bet would be to call or email the guy from lt1swap he does stock tuning and will help you with a lot of wiring questions or you could send the harness to him and have him do the work and tune the computer for less than 300 bucks... And really if you have the harness, and the injectors and coils are good it's probably cheaper to go efi.

Just some food for thought.
 
War Machine

War Machine

Not-quite-so-new-guy
Nov 11, 2014
23
1
So what is everyone using as far as a driveshaft goes? Does a stock Malibu driveshaft fit right in or will I need to get a longer or shorter one? I'm using a 5.3 with 1" setback plates and a short tailshaft th400 and a stock Gbody 10 bolt.
 
cyrus_the_great

cyrus_the_great

Greasemonkey
Sep 8, 2009
237
16
IRAN
War Machine said:
So what is everyone using as far as a driveshaft goes? Does a stock Malibu driveshaft fit right in or will I need to get a longer or shorter one? I'm using a 5.3 with 1" setback plates and a short tailshaft th400 and a stock Gbody 10 bolt.
1" setback plate dose not work with th400 and stock driveshaft because th400 with short tailshaft is 1" longer in compare to thm350(6" tailshaft) yet
 
War Machine

War Machine

Not-quite-so-new-guy
Nov 11, 2014
23
1
cyrus_the_great said:
War Machine said:
So what is everyone using as far as a driveshaft goes? Does a stock Malibu driveshaft fit right in or will I need to get a longer or shorter one? I'm using a 5.3 with 1" setback plates and a short tailshaft th400 and a stock Gbody 10 bolt.
1" setback plate dose not work with th400 and stock driveshaft because th400 with short tailshaft is 1" longer in compare to thm350(6" tailshaft) yet
Ok I got you. But my car had a 700r4 so is that as long as a short shaft th400?
 
cyrus_the_great

cyrus_the_great

Greasemonkey
Sep 8, 2009
237
16
IRAN
War Machine said:
cyrus_the_great said:
War Machine said:
So what is everyone using as far as a driveshaft goes? Does a stock Malibu driveshaft fit right in or will I need to get a longer or shorter one? I'm using a 5.3 with 1" setback plates and a short tailshaft th400 and a stock Gbody 10 bolt.
1" setback plate dose not work with th400 and stock driveshaft because th400 with short tailshaft is 1" longer in compare to thm350(6" tailshaft) yet
Ok I got you. But my car had a 700r4 so is that as long as a short shaft th400?

th400 with short shaft is 2" shorter than 700r4.
 
War Machine

War Machine

Not-quite-so-new-guy
Nov 11, 2014
23
1
Got ya. Thank you.
 
War Machine

War Machine

Not-quite-so-new-guy
Nov 11, 2014
23
1
Do I need to use a th400 stall converter or is there a special converter made for LSx - th400?

Edit: I found out you can use a stall converter made for a th400. Nothing special.
 

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