Hi yall! Newbie ls swapper here. need advice for a ls swap on a 93 tbi 4.3 nv3500

[Dads93stepside]

hey guys! my names tom.Im tackling a project for my dad that is long overdue. so long story short my dads turning 50 and having 4 sons hes really had to work his ass off my whole childhood. from having 3 jobs and selling his possesions to support us (had to sell his 71 nova when i was born in 92) and i have his 93 2wd 4.3 tbi 5 speed single cab short bed stepside c1500 truck to fix a "coolant leak". he loves the truck but this poor ol guy needs more power! what better way to make his eyes pop when i pop the hood when i return it with a 2004 5.3 i just bought! So ive been recommended here from so much research and i just want you experienced guys to hopefully help me out. So heres the run down. just bought a complete 04 5.3 out of a wreck. complete. harness and ecm out of it. his truck has the 5 speed.believe its a nv3500. so from what ive gathered this is what ive gotta do and id like for you guys to correct me if im wrong. So first off i need to get the harness modified to stand alone along with a pcm reflash. with the reflash it would be deleting VATS,all the emissions crap evap,egr,o2s etc., block off plates for evap and egr on intake, set of ls swap motor mount brackets, headers, two fittings to thread the two sensors (temp and oil pressure) off his motor into said fittings?and just separate the two wires from his stock harness and slip em into the loom of the stand alone, a v8 throttle cable from a 99 n up truck or tahoe, electric fans (going to ask harness modifier to add this harness in,a 98-up vortec fuel pump to supply the 60lbs of pressure needed,fuel lines to run from ls fuel rail down to pump,some sort of cold air intake setup. Now my questions for the engine stuff. 1. What headers will work best?just some generic shorty ebay specials for any 99-04 ls? id like to try n use his stock ypipe or one off an ls motor unless there is true dual ypipe one ofyou vets knows about that i can add pipe onto after i take care of the critical bend fronm the driver side over to the passenger side to clear the tank. 2.What electric fan setup can i use that will fit on his radiator with little mods and will plug into the fan harness that would be added to the stand alone. 3.What fuel pump should i use? and from my research i cant decipher if these ls swaps the guys are physically swapping the whole sender unit complete from a 98- up truck? or are they just swapping just the pump into the original fuel sender? if i did get a whole 98-up assembly,what do i do about the harness that would of plugged into the original pump? is there a jumper harness adapter? or is it the same?also what do i do about fuel lines? is the tbis supply and return too weak to supplement the 60psi to what im guessing the stock 4.3s 30 or so lbs? Now onto the transmission. 1. I know i know i hear all about how the nv3500 wont hold yada yada. hes old lol hes not gunna be ragging on it.just want him to have a nice crusier. the trans will bolt up to said 5.3 correct? 2. from what ive gathered to make this setup work i need the nfw1050 flywheel,pilot bearing napa 6302-vsp43, release bearing national 1377c, 4.8 clutch kit and pressure plate. from what ive learned this shall all bolt up and ready to rock? guessing his stock bellhousing bolts are standard so just go grab any bellhousing bolts from any 4.8,5.3,6.0 truck auto or manual?guessing they are all the same? or would it have to be a manual truck? 3.Didnt get a starter with this engine. what starter will sork? i know this truck had the 7/16s long bolts bolting up. if i'm not mistaken the ls starter is different way of bolting up or am i incorrect? Sidenote-anyone know of a good air intake setup? also i didnt happen to get a maf.... will i need one? and modify it into air intake tube? I sincerly appreciate any help gentleman.i know you guys are prob sick and tired of guys just coming on here with "how i do this"i put forth my days of scanning info and my notes and put it all together here just to kinda get it checked over by the pros here on LS1truck! trying my best here and just trying to hook up the man who busted his ass his whole life and is turning 50 and deserves this.Any and all tips tricks well appreciated! Thank you all! this wensite is great!!! p.s im a mopar guy (dont shoot!) but i love all domestics! reading through here im damn near convinced i should just swap my damn 1972 roadrunner with a 6.0 hahaha.

[brianmcb]

I did same swap last winter in my 95. 4.3 5spd to 5.3 5spd. You asked alot of questions. LOL. You also need the v8 motor mounts that bolt onto the frame of your truck. I used this fuel pump in my stock sending unit http://www.highflowfuel.com/i-478352...1988-1995.html
I used all new stainless braided fuel lines because the stock rubber ones from the tbi setup are to weak to handle 60psi. If your 5.3 is an 04, than it will also be drive by wire so you need the TAC module and the electronic pedal to. I made my own stand alone harness, and using a dual speed electric fan from the junk yard. From a Ford minivan. The stock 5.3 manifolds fit, but I went with schoenfeld long tube swap headers for 88-98. Your right about the pilot bearing and flywheel, the stock throwout bearing works just fine in my truck. I've beat the piss out of the nv3500 and it's doing just fine.

[1991SSP]

sounds like you pretty much have it covered...i used a fuel pump for a 96 vortec V8, Ep381 I believe when I did my swap.. knock on wood I have ran the truck for 5 years with no issues from the factory fuel lines


Hats off to you for doing the suprise swap for your father... I did a swap on my dad's 96 truck this summer... his ole 5.7 was tired and worn out.. he's been all smiles since I put a 4.8 into it

[Dads93stepside]

sounds like you pretty much have it covered...i used a fuel pump for a 96 vortec V8, Ep381 I believe when I did my swap.. knock on wood I have ran the truck for 5 years with no issues from the factory fuel lines


Hats off to you for doing the suprise swap for your father... I did a swap on my dad's 96 truck this summer... his ole 5.7 was tired and worn out.. he's been all smiles since I put a 4.8 into it

. thats what im hoping for! so everything i said is correct then?

[Dads93stepside]

hey guys! my names tom.Im tackling a project for my dad that is long overdue. so long story short my dads turning 50 and having 4 sons hes really had to work his ass off my whole childhood. from having 3 jobs and selling his possesions to support us (had to sell his 71 nova when i was born in 92) and i have his 93 2wd 4.3 tbi 5 speed single cab short bed stepside c1500 truck to fix a "coolant leak". he loves the truck but this poor ol guy needs more power! what better way to make his eyes pop when i pop the hood when i return it with a 2004 5.3 i just bought! So ive been recommended here from so much research and i just want you experienced guys to hopefully help me out. So heres the run down. just bought a complete 04 5.3 out of a wreck. complete. harness and ecm out of it. his truck has the 5 speed.believe its a nv3500. so from what ive gathered this is what ive gotta do and id like for you guys to correct me if im wrong. So first off i need to get the harness modified to stand alone along with a pcm reflash. with the reflash it would be deleting VATS,all the emissions crap evap,egr,o2s etc., block off plates for evap and egr on intake, set of ls swap motor mount brackets, headers, two fittings to thread the two sensors (temp and oil pressure) off his motor into said fittings?and just separate the two wires from his stock harness and slip em into the loom of the stand alone, a v8 throttle cable from a 99 n up truck or tahoe, electric fans (going to ask harness modifier to add this harness in,a 98-up vortec fuel pump to supply the 60lbs of pressure needed,fuel lines to run from ls fuel rail down to pump,some sort of cold air intake setup. Now my questions for the engine stuff. 1. What headers will work best?just some generic shorty ebay specials for any 99-04 ls? id like to try n use his stock ypipe or one off an ls motor unless there is true dual ypipe one ofyou vets knows about that i can add pipe onto after i take care of the critical bend fronm the driver side over to the passenger side to clear the tank. 2.What electric fan setup can i use that will fit on his radiator with little mods and will plug into the fan harness that would be added to the stand alone. 3.What fuel pump should i use? and from my research i cant decipher if these ls swaps the guys are physically swapping the whole sender unit complete from a 98- up truck? or are they just swapping just the pump into the original fuel sender? if i did get a whole 98-up assembly,what do i do about the harness that would of plugged into the original pump? is there a jumper harness adapter? or is it the same?also what do i do about fuel lines? is the tbis supply and return too weak to supplement the 60psi to what im guessing the stock 4.3s 30 or so lbs? Now onto the transmission. 1. I know i know i hear all about how the nv3500 wont hold yada yada. hes old lol hes not gunna be ragging on it.just want him to have a nice crusier. the trans will bolt up to said 5.3 correct? 2. from what ive gathered to make this setup work i need the nfw1050 flywheel,pilot bearing napa 6302-vsp43, release bearing national 1377c, 4.8 clutch kit and pressure plate. from what ive learned this shall all bolt up and ready to rock? guessing his stock bellhousing bolts are standard so just go grab any bellhousing bolts from any 4.8,5.3,6.0 truck auto or manual?guessing they are all the same? or would it have to be a manual truck? 3.Didnt get a starter with this engine. what starter will sork? i know this truck had the 7/16s long bolts bolting up. if i'm not mistaken the ls starter is different way of bolting up or am i incorrect? Sidenote-anyone know of a good air intake setup? also i didnt happen to get a maf.... will i need one? and modify it into air intake tube? I sincerly appreciate any help gentleman.i know you guys are prob sick and tired of guys just coming on here with "how i do this"i put forth my days of scanning info and my notes and put it all together here just to kinda get it checked over by the pros here on LS1truck! trying my best here and just trying to hook up the man who busted his ass his whole life and is turning 50 and deserves this.Any and all tips tricks well appreciated! Thank you all! this wensite is great!!! p.s im a mopar guy (dont shoot!) but i love all domestics! reading through here im damn near convinced i should just swap my damn 1972 roadrunner with a 6.0 hahaha.

. so i dont need the national 1377c bearing?

[brianmcb]

. so i dont need the national 1377c bearing?

I didn't use it. Oem bearing works perfectly fine.

[brianmcb]

Also, the stock LS truck oil pan will hang about 2" below the c1500 engine cross member

[Dads93stepside]

no biggie dad drives like a grandpa.trucks not lowered or nothin. dont even think inswapping rear ends he doesnt burnout lol

[1991SSP]

Here's my breakdown, best I remember when doing my truck

Dirty dingo mounts
Changed frame mounts to ones for 305/350... you can change these without dropping the lower control arms, you will need someone to help hold the top bolts while you use an extension and swivel from below
Nelson stand alone harness and fan harness from nelson
PCM program
Electric fans
New heater Hoses ,, upper and lower radiator hoses
I reused my 4.3 ac compressor mount/belt tensioner,, had to cut bottom portion of it off and make a few support brackets to mount it to the 5.3
I used a 1998 S10 fuel filter, it threads onto the stock fuel line...on the pressure side I used dorman metal fittings and Nylon line
Return side I used dorman 5/16 metal fitting and rubber fuel pressure rated line,,, cut the metal return line underneath,, slipped the rubber line on and clamped with 3 clamps
I left the entire 4.3 stock harness under the hood,, clipped off all the connectors and put heat shrink on the ends of the wires, tucked them into the loom,, this way I kept my AC wiring in stock location

I ran wires for tach and speedo directly from the PCM to the cluster... Since you are running the 5 speed I would imagine you can just leave all the original harness plugged into it and your speedo will funtion correctly,, I swapped a 03 4l60e into my truck when I did the swap

[Dads93stepside]

heres my question. will this clutch kit solve all my issues of mating up my nv3500 to the 5.3? already got the nfw1050 flywheel.my question is is this pilot bearing the same one i need in this kit? i posted the link on my next reply below