swapping from a NBS 4.3 to a V8

[Dirty 30]

Im getting pretty close to getting done with my swap. I think in a couple days it will be done.

Are the rear ends the same???? This question should be added to the main post.

[skeet123]

sorry dirty i really dont know but i would think they would be the same.

NICE SITE guys!!!!!! learned alot here just from reading...

anyway have a question or 2 myself i am doing a swap now from 4.3L to 5.3L in a 99 chevy silverado as i found it pretty easy it seemed i only needed to change the mounts, read someone mention spacer plates (where can i find these) local auto store.i have the motor mounts for the 5.3 it seems i need the lower mounts to the frame. as for the exhuast i must have gotten lucky or something, the manifolds from the 5.3l bolted right up to my existing exhuast, anyway.as for the fuel lines i cut the ends off and added fuel flex hose (clamped)so the 5.3 fired up i will be doing some fine tuning this week but i need a few brackets like the alternator and air compressor bracket guess i can get these at a local salvage yard ...or from the dealer ..

[Dirty 30]

Originally Posted by skeet123

sorry dirty i really dont know but i would think they would be the same.

NICE SITE guys!!!!!! learned alot here just from reading...

anyway have a question or 2 myself i am doing a swap now from 4.3L to 5.3L in a 99 chevy silverado as i found it pretty easy it seemed i only needed to change the mounts, read someone mention spacer plates (where can i find these) local auto store.i have the motor mounts for the 5.3 it seems i need the lower mounts to the frame. as for the exhuast i must have gotten lucky or something, the manifolds from the 5.3l bolted right up to my existing exhuast, anyway.as for the fuel lines i cut the ends off and added fuel flex hose (clamped)so the 5.3 fired up i will be doing some fine tuning this week but i need a few brackets like the alternator and air compressor bracket guess i can get these at a local salvage yard ...or from the dealer ..

when you swaped you engine did you get a security light and didnt start? or did it start up right away?

[ssv6silverado]

I have a question about your wiring harness. I'm swapping from a 4.3 to an 8.1 and i want to know where you got your wiring harness from for the motor and if it is the same wiring harness for a 6.0 possibly

[skeet123]

Originally Posted by Dirty 30

when you swaped you engine did you get a security light and didnt start? or did it start up right away?

yes i got a security light problem (didnt start) before i was actually about to fire it up, what i did was i got a matching ecm and pcm from another 99 and reflashed it

[WarnOffRoad]

the truck im looking at getting is a 04 NBS ext cab with the 4.8 V8 and 4l60e, the motors only got 70 on the clock, but i dont like the idea of the 4.8. So in a year or so id like to swap to a 5.3 or a 6.0 would i need a new wire harness, or a new computer/ reflah? what about motor mounts? I know i know your saying just look for the 5.3s, but its so hard to find anything but a 4.3 around me, without paying out the @ss, so i found a good deal on this one.

Thanks
-Matt

[submunky]

Does anybody know if they make an adapter plate to fit a throttle body on to a carb intake? Or maybe if a throttle body would somehow bolt on to a carb intake?

[chevyryder]

can i take a 5.7-700r4 and put it in a 98 1500 with 4.3-5 speed?
what would i need to do this?

[modular93fox]

gota couple of question on swaping a 5.3 into my 01 4.3.

Whats the difference on the fuel lines bewteen motors, should i grab them off the donor truck or will the 4.3 lines work?

Do i need to grab the 5.3 radiator shrouds or will the 4.3 shrouds work?

ive read that the fuel pump will work, so thats not a question, but transmissions... should i grab the donor trans? i dont know what i have now 4L60 or what. but are the 4.3 and 5.3 trans the same? 2nd part of the question whats the difference between the 4L60 and 4L80

after doing the v8 swap have did you find it necessary to upgrade to the donor radiator?

i will be getting a 200X 5.3 and trans (if i need to buy the trans) and harness for 1400 from one of my junk yards im buddies with. i will get my friend to reflash my PCM to accept the new motor. i have the concept of the swap down, but would like to know what im getting into before i do. i have previous history on doing stuff like this, i.e. my screen name, i stuffed a 2003 4.6 2v into my 93 Mustang. anyway, thanks.
clint

[jba1rylie]

I Dont Know If This Will Be Helpful To Anyone, But I Run A Auto Recycler Yard And Might Be Abvle To Answer A Few Question As Far As Accessories , Transmission And Drive Shaft Crossovers On Swaps, I Just Recently Put A 6 Speed Out Of 01 Trans Am In My 04 Silverado. It Was Easier Than I Thought. Mounts Were Indentical All Plugs Were Same, Had To Use Pilot Bearing From Ta. Didnt Even Have To Modify Driveshaft... I Found That The Auto. Driveshaft Were 3 Inches Shorter Which In Return Was Perfect Fit. That Means The U Joints Are Same On Cars And Trucks. The Late Model 4l60's Have Bolt On Bell Housings Which Can Be Swapped, But The Bellhousing On The 6 Speed Bolted Right Up To My Block. As Far As The Auto's From The 5.7 Into The 4.3-i Have Run Into Problems With Bolt Pattern On Bellhousing Being Different And The Torque Convertor Uses A Different Style Which Was Another Problem. I Really Didnt Spend The Time To See If The Convertors Would Swap But I Dont Think Thewy Will... But The 4l60 In A 4.3 Is The Same As A 4.8 And 5.3 In The 99-ups. Only Thing You May Have To Swap Is Tailhousing--if You Go From Reg. Cab To Ext Cab. Or Just Move Rear Mount Back One Notch, But This Will Involve Drilling Two Holes In Frame .hopefully This May Be Of Use. Good Thing About My Job Is I Get The Luxury To Get A Motor And Sit Them Side By Side To Compare ... I Learn Alot Of Tricks From This.

[jba1rylie]

One Additional Not Is On The Bolt On's Accessories. In The 04 Up The Power Steering Is Diferent Than Prior Years As Well As I Think The Ac Compressor Location, And The Front Mount.. Yes You Can Replace The Hole Set Up But You Cant Just Swap The Power Steering Pump. Also The 04 Had Electric Fans, I Personally Would Sacrifice The Few Hph. Losses And Put A Fan Clutch Back On. It Seems To Me That It Cools Better.

[swearfinger]

Im about to make the swap too. Heres the problem (i asked in technical forum and no one would help) I have a 2004 with the manual trans in my v6. What is going to happen when I have the computer flashed and it thinks I have an AUTO when in reality I dont? Chevy never made that combo, so I really dont have any choices, or do I?

[gearheadperkins]

what about swapping to a carb'd 350 5.7

[swearfinger]

I would love to make the easy swap to something carb'd but due to Illinois EPA laws i can only put into my truck an engine that was available that year as an option AND it MUST have all the emissions equipment installed on it for that particular engine with no check engine light on and no trouble codes saved or it will auto fail. I'm almost at the point where I'm going to have it registered out of state in an area in which they do not have the EPA restrictions.

[gearheadperkins]

do anyone out there have any info on what is involed in swapped to a carb'd v8

[brettp06]

it will be a beast

[Fast305]

FWIW, GM built FACTORY L31 350 Vortec NBS trucks. This one is a 2002 1500 Suburban, FACTORY STOCK GM BUILD.

[Fast305]

Found a little video of the FACTORY NBS L31 combination.

http://www.youtube.com/watch?v=1Ma8Gu3UH-U&NR=1

[john_1326]

When this conversion was done did the gauge cluster work in the converted vehicle or was there other things done to make the gauge cluster work?

[96c15004.3]

When you are finished can you tell us approximately how many hours and $$$$ the swap ended up costing you.

Thanks