98-00 Vortec 5.7L swap Sticky

[carter]

I think it'd be a good idea at this point to add a sticky to the top about the whole 98-00 vortec 350 swaps. There seems to be a TON of the same questions being asked. The other sticky is filled with info from the 82-03 models and not everyone has time to read through 25 pages lol.

I'll do my best to explain whats needed but i dont have the knowledge that some people here do. I am by NO means an expert, so if you think YOU are and see that I've made a mistake...please contribute. Thanks.


SO...you have your self a 98-00 Sonoma and you've got your eye on a vortec.

I have not tried the swap with the 5.7L PCM and harness. GM has a function on their newer PCMs called VATS (Vehicle Anti Theft System, if the chipped key is not used it WILL NOT START),however the sensors are mostly the same i found. So i used the 4.3L harness and flashed 4.3L PCM to 5.7L

PCM - you'll need your 4.3L pcm flashed with a 5.7L program and you'll need the pin out (schematic) and find any differences. What i did was take the 4.3L pin outs and wrote them all down on half a piece of paper (yes this is a lot of work not necessarily needed but it helps if you've never done this before). Next i looked at the pin out of a 5.7L PCM of the same year (however the 99 is the closest i could find) i then wrote all of the functions for each pin out on the other half and compared them. Highlighted the differences and went from there. The main differences were the injectors, but depending on which PCM you HAVE and which one your FLASHING with you may have more changes to do such as transmission functions.

EDIT: OK, so i've had TONS of pm's about the adding injectors part of the swap so i drew a VERY crude diagram and hopefully a visual will help some guys out. The colors and numbers are NOT accurate and are only used to show variation between wires. When i say V6 pcm and V8 pcm, if you've flashed yours this is the SAME PCM and I am just refurring to the program.

SO...what YOU need to do if your doing this swap is have your V6 PCM flashed with the V8 program of your year or one similar. This is why its very important to look up the pin outs on alldata or equivalent to find out what the pin out looks like on it and your old one. (ie) what wires do what for both. When you look up your new pin outs on alldata it helps to print off the NEW pin AND the OLD pin outs and compare them. When I did it I wrote every function down for both in a chart side by side and wrote which wires were not in the same place. You MAY need to swap a few wires around but for the most part it should be similar. Write down on paper any differences (ie) The injectors 1-6 will most likely NOT be in the same location as the v8 versions pin out. So if your v6 pin 32 was injector #2 it maybe injector #5 on the V8. You will also need to get the diagrams for the injector wiring "hats", the little black box with your injector wiring in it.

next step:

In this case i've drawn that the new program for the V8 PCM says:

PCM pin # 41 yellow wire = injector #2
PCM pin # 25 brown wire = injector #5
PCM pin # 20 red wire = injector # 8
PCM pin # 05 green wire = injector # 7

I only did 4 wires to give you an idea, im sure you guys can figure out the other 4. I've shown 2 exsisting wires v6 wires (yellow and brown) and the 2 new ones (red and green) you must add.


Once you've made note of which wires do what; transfer this to the truck.If pin 32 is injector #2 and its a yellow wire on your V6 sheet of paper and on the V8 sheet it says injector #2 belongs in pin 41, put out (or cut) the wire and place (or splice) it in the pin 41 possition in the V8 PCM. Done. Do the same for injectors 1-6.

For injectors 7 and 8 you need to add or splice into the injector 7 and 8 wires and then run the wires back to the PCM with the rest of them and plug them into the injector pins. In my case i've drawn 7 and 8 are red and green (you can use any color of wire you want) and the 7 belongs in pin 5 and 8 belonging in pin 20. I've colored these pins PINK to show they are the new injector wires. These pins maybe used or they maybe unused. If you ARE USED then you must move those wires to where they belong on the new PCM.


* To remove a wire carefully remove the coloured covers on your pcm. Carefully pry up on the white "fingers" that hold the wires in place (i wish i had taken more photos of this part) and lightly tug on the wire from the back, it should come out no problem. To place it in the pin that you want simply just push it in and you'll hear it click into place. If you can not figure this part out you CAN just cut and splice but i didnt want any cut wires in my harness so I removed them. I guess if your really good at soldering it makes no difference.



Does this clear anything up?


NOTE
I personally used a 01 computer (yes, much different) and re pinned all the wires so i could use a PCM that had been tuned with HP tuners by a friend before so it was free to try and it worked.

Intake - I reused the 4.3L intake and flipped the valve covers around left to right so make filling it with oil easier. I also used the 4.3L MAF, it seems to work with the flash but i also had mine tuned so you MAY need to use the 5.7L intake and get a cowel hood.

Fuel lines - The 97 i used had the same size fuel lines, but there is an adapter on top that you'll need because this is slightly different than the 4.3L. Your stock fuel lines will screw into this.

Accessories - I was able to use all of the 5.7L accessories. Alt, power steering pump, everything.

Rads/Fans

Hoses - i re used the hoses from my 4.3L. If yours wont work, find out what diameter you need and find either a generic bendable one or a long enough hose from another car/truck and just cut it to fit. easy pleasey.

cheapest route - I found the 99 or 00 dodge intrepid fans fit the best out of anything i tried at the wrecker (i tried ford fans, jeep fans, everything i could find) they require a little cutting on the outside edges and move quite a bit of air. another plus is that they are super easy to find and cost me $40. yay!

I also re used the 4.3L rad and moved it up (requires cutting the core support) this gave me just enough room to safely put a load on the engine and have nothing rub

I also wired the fans into the PCM so that it turns the fans on. I was lucky enough to have a friend that knew alot about wiring and he modded my stock fuse box to use the relay for the rear defrost on blazers. He wrote up a sticky on it somewhere on here...it works very slick, with HP tuners you set when the fans come on.

You can also wire them in to a temp switch with a relay and they will work just fine, there is a sticky on this as well somewhere around here.


Expensive but better route
Corvette rad moved up with aftermarket slim fit fans. pretty self explanatory.

Driveline - i did not need to modify anything drivelinewise on my 00' ext cab, im almost positive you wouldn't need to on any model as long as you have the 4L60 trans.

Oilpan/Filter - I used a filter adapter from any old SBC tha has the filter on the driver side, next to the block. The 4wd motors came with remote oil filter lines that just love to leak and cause headaches. You do not need these.

The 4wd Oilpan fits...but is close. I tapped a few small dents in the pan with a rubber mallet just to keep it from rubbing. Be carefull not to crease the pan and cause a possible leak.

I've never seen or tried a 2wd oilpan to see if their different.



Cost - I got my motor from a wrecked 97 halfton 4wd. I've heard of H.O 5.7L out there...i was not lucky enough to come across any. lets break down the pricing.

$500 - motor
$40 - Fans
$80 - fluids, trans, engine oil, power steering
$100 - used shorty's already sand blasted and coated
$250 - misc bolts, hoses, gaskets, i replaced the intake gasket on mine (VERY common problem on these motors)
$50 - mounts ( i had adapter plates made and they worked great)
$800 - full exhaust, not really NEEDED but i wanted all my hard work to sound good. I got dual 2.5" with a dual in dual out flo-pro muffler. Its nice and quiet and still sounds great.
$100 - GM charges around an hours labor to flash a PCM, you MAY have to send yours out to someone who can bench flash PCMs.

= $1920. I also sold my perfectly fine 4.3L for $400...so it cost 1580...Chya!

Also note that if your on bags...you'll need to buy SD upper control arms. Their not that much anymore since power performance is making the cross shafts now. Also there is a sticky for installing them in the bags section.

*If your on a budget...the auto wrecker is your best friend!*

Of course you could go all out and spend more...i was on a tight budget and did my best to minimize costs.

So yea... please excuse my bad grammar, i've never wrote one of these out before. If anyone wants to ellaborate on this...and make it a proper sticky, i've probably missed a few points...that'd be awesome and hopefully not only minimize the number of 5.7L into 3rd gen s10 threads by having a place for all those questions, but also help some guys out.

I'll add to this as i remember more...i did my swap last year and i know i missed something. Good luck and happy swapping! The work is SO worth it...

heres a video of my first crank to give you guys some motivation

...i was holding my breath and crossing fingers lol...
obviously needed more tuning and sounds rediculous because of the open headers :P

I'll post a video of out it runs now once its back together...i've been busy with my 5 link and everythings in pieces

[dirty_drew]

It would be nice to include those who have the 2.2L too

So whats the deal with the 2.2L PCM? If you get another PCM out of the same car that the engine came with, then could you use that?

[carter]

you'd probably need the harness and PCM then, as far as i know, i've had no first hand experience on the 2.2 swap

[Maaso]

The LT1 year 'vettes (92~96) came with an offset oil filter adapter. It dropped the filter about an inch-inch point five or so. But it tucked the filter so much closer to the pan freeing up precious exhaust room.

For L31(97~03 Vortec 5.7)
And you still need to run wires from the PCM to the new V8 fuel "spider" to signal the two extra injectors. Just telling the computer there are two more there with no way to fire them wont do any good.

All of the stock 4.3 accesories...brackets, AC, alt, event he 4.3 water pump will bolt right up to the 5.7, save some money buy reusing what you got if you can.

Your factory tach will read zero afterwards too....some companies out there sell adapter/module things to fix this though.

You won't be able to close the hood because the stock AC lines on a stock compressor with hit the hood.

[carter]

shit i knew i forgot something...

yea you gotta add 2 wires from the top hat to the PCM...pretty simple really. Then you have to find out where the pin out for the 2 injectors are on your to-be-flashed PCM and plug them in the right slot.

Thanks Maaso, i'll add that to my post once i figure out how to edit...lol

[chevyistheway]

definaltly should be stickied
im in the process w/ my swap, did mine pretty much like this. ive got a vette rad and ill be using the v8 pcm thats already been tuned and the v6 harness w/ v8 accessories
should know this weekend
fixing the starter and then its go time

[chevyistheway]

well for the vette rad, a 92 wont work to well, it sits up too high and its not as wide
so what year of a vette radiator

[03blazer]

Hey guys,

I just thought I'd add my input on this swap. I just recently helped my buddy perform this same swap into a '02 Sonoma. Sry, but I didn't get to take any pics...

Anyways, Carter has named off just about all of the important stuff for this swap. There are a few things that I found to be easier. (for me at least)

For the fuel injector wiring, we removed the entire injector plug from the V8 harness and swapped it out in place of the injector harness for the 4.3. We got lucky and had access to an AllData system to pull up all of the wiring diagrams. We re-pinned the wiring harnes accordingly, used EFILive (i think) to re-flash the ECM, and got everything in place. We used an '02 Express Van tune.

There is a number of ways to do the motor mounts. For this swap, we took some 3/8" steel plate and cut out some pieces to bolt between the engine an the motor mount shell so we could use the stock V8 motor mounts. We mounted some stock V8 mounts to the frame of the truck and placed the shell on it with the bolt through it. We then, bolted the steel plates to the engine, put some double sided 3M tape on the shells and got the engine where we wanted it and lowered it in place. The tape allowed the shells to stick in place on the plates. We pulled the bolts out and lifted the engine with the shells stuck to the steel plates. We marked the holes on the plates and drilled them out, slotted them (for adjustability) and mounted the shells to them. Sorry I didn't take pics of how it was done, I didn't know I'd be writing about them... I'm trying to think of a way I can kinda make a drawing to show what they looked like...

As far as headers go, we just used a set of normal shorty headers from Jegs. We also used the stock Vortec V6 intake setup.

For the cooling system, we used a '86 Corvette radiator with a custom sheet metal shroud and dual 10" puller fans, a 180 degree t-stat, and for the hoses we took some steel pipe and bent it as needed and used about 3" of rubber hose on each end to attach to the engine/radiator.

We re-used all of the trucks stock accessories. The A/C still works as it did before. One thing I forgot to mention, was that we also slotted the holes in the shells on the motor mounts to set the engine a little lower. The reason we done that was so the A/C lines would clear the hood better. He has a cowl hood on it, but just wanted the extra room for some reason...

That's about all the additonal swap info I have...

Here's a quick run down on the truck setup

• 98 Chevy truck block
• Eagle I-Beam rods
• Flat top pistons
• Modified Vortec heads
• Custom cam (specs secret... lol)
• Port matched intake
• Injector spider modified for more fuel
• Dual 2.5" exhaust with Spintech Pro-Shootouts and no cats
• Built 4L60E with Billet servos and a 3000 stall
• 4x4 rear axle with moly axles and auburn posi (3.73 gears)
• Modified Xtreme wheels (16x5 front and 16x10 rear)
• Drag radials (not sure on size)
• Tuned with EFI Live

I know there are some things I forgot in his setup. The truck ran a best time of 11.89 at the track. It was dyno'd at 447rwhp. Has a bit of a traction issue...

If I wasn't on deployment, I'd see about taking pics of it to post... but...

If anyone needs any further info on this swap, feel free to ask... I'll post more info if I know the answer...

Hope this helps!

[zap-mann]

Do tell more on what all mods were done to the Vortec heads and the fuel spider. I am in the middle of this same swap. Also, what is the RPM band on that cam?

[chevyistheway]

i had to beat on the fire wall to have enough room for my passenger side shorty header to bolt to exhaust
also had to extend a few wires such as the crank sensor and apperently the v8 came w. a tach so i had to cut it and use the v6 plug since my truck didnt have one
thats all i can think of right now

[03blazer]

Quote: Originally Posted by zap-mann

Do tell more on what all mods were done to the Vortec heads and the fuel spider. I am in the middle of this same swap. Also, what is the RPM band on that cam?

Umm, for the heads... They aren't heavily modified. He just had them machined for a larger cam, bigger valves installed, and ported and polished. A nice improvement over stock Vortecs.

For the injector spider... He sent it off to some company... I saw a thread about it in the 4.3 section... they took it and modified the injectors/poppets for higher flow. They flow like 36lbs or so...

As far as the cam powerband... its like 2800-6500... it's actually not a very big cam... it makes AWESOME power though...

[carter]

excellent addition 03blazer!

I wish mine was capable of such awesomeness haha

[03blazer]

Thanks man!

These engines can be made to perform quite well with modified stock heads and intake. I'm working on collecting parts for a swap in mine when I get back from deployment. You can see pics of my truck and the engine block in the thread I started.

[carter]

I had no idea they had potential with head and intake mods...i didnt do enough research before i did my swap and found out after the lumpy cam sound i wanted...isnt very possible with the vortec heads lol...oh well, im looking for a 6.0L now and trying another swap next winter...their fun! haha this was my first time removing an engine ever and had a blast

[03blazer]

You can get the sound with the right cam... might not be the best cam for performance... but you could get the sound.

The cam that's in my buddy's truck sounds almost stock. It has a little bit of a chop to it though... If it had a single exhaust with a stock style muffler, you'd never know it had a V8 in it.

[V8Sonoma96]

I wish someone had more info on 2.2 to V8 swap. I got 96 sonoma. I picked up 96 5.7 motor out of 96 Tahoe with harness and PCM. 2.2 is way different that 5.7. Its much easier to swap v8 into 4.3 truck. Its almost the same.

Can I use the 5.7 harness and PCM?

[03blazer]

My suggestion would be to find a stock harness from a 4.3 truck, remove the whole injector plug and wiring from the 5.7 harness, and put it in place of the 4.3 injector plug and wiring. You should be able to use the computer from the 5.7 though... you may have to get the pinout diagrams and move some of the pins around in the connectors. Shouldn't be too hard if you're any good with wiring.

[V8Sonoma96]

Does anyone know what is the main difference between 4.3 and 5.7 harness?

[Drumer919]

fuel injector harness and wire lengths.

You can get a 36lb/hr spyder injector from wynnjammer superchargers, $400 plus core but its the first design, not the 2nd design with the individual injectors where the poppets go.

Also to use a big cam with stock un-modded vortec heads you can use factory GM LS6 springs($64 from GM dealer), comp cam retainers($50 jegs/summit) and dodge datoyna turbo seals($20 from the parts store) and for under $150 with gaskets and allyou can allow up to .550 lift" cams in otherwise stock heads.

I went this rout and am running a .525 lift cam no problem.

[More Displacement]

You should also have too run an extra 02 sensor wire if you dont swap the harness. I have been thinking of this swap a lot recently but want to get the brakes and suspension up first. Not many people try the 2.2 to 5.7 swap. A lot of work. Most people that look to put a 5.7 in an s-series look for a truck with 4.3 and manual trans. A lot of people say to switch the trans out for a fullsize trans, not positive if theres a difference. I think you guys did a great job of organizing this info it should help anybody out whos attempting to do this.

Got some of my info from http://jaguarsthatrun.com/. They have some good info (mostly on first gen swaps but some on later) and sell parts too.

[Kampz69]

what is the extra O2 sensor for, does the 5.7 have a precat sensor also?

[More Displacement]

As far as I know any 96 and later trucks have pre and post cat O2 sensor. Most (because Im not going to say all) 96 and up 5.7 trucks have two cats (one on each bank to efficiently "clean" the exhaust. They have two post cat O2 sensors for diagnostic reasons (no guess work which cat failed).

[Kampz69]

well then the 4.3 would have that too if its a 96+ thing...if its an extra post o2 sensor, that could be tuned out or replaced with an o2 sim. i didnt know if it was another precat sensor that had to be added....i thought my blazer only had one.

[More Displacement]

5.7 truck- right and left banks, dual exhaust down through the truck that usaually turns into a single at the muffler. (layout of exhaust system) So two manifolds, two pre cat O2 sensors, two cats, two post O2 sensors then the exhaust merges into a single exhaust.

4.3 - right and left banks, dual exhaust to the cat were it merges. (layout of exhaust system) So two manifolds, two pre cat O2 sensors, exhaust merges, one cat, one post cat O2 sensor.

The post cat O2 sensors are strictly to monitor the efficiency of the cats where the pre cat O2 sensors are to help maintain a proper aif fuel artio.

All EFI v-engines have 2 pre cat O2 sensors and depending on the exhaust system and age the car may have one, two or no post cat O2 sensors.

You would just end up one post cat O2 sensor short which doesnt harm the engine it will just have a constant code telling you something about one of the banks and the reading of the O2 sensor. Again doesnt harm the vehicle but who wants to go through all this work and then have a constant code becuase of a few wires. Emulators are ok but if it has to pass emissions it wont work.

[Kampz69]

so, then, no additional sensor would be needed if one was having the 02 postcat sensors tuned out. i understand the emissions issue, that may effect some.

so all in all, all thats needed wirewise in this swap is the addition of two fuel injector wires (not including the postcat o2 sensor), and lengthening of others...thats it?

[03blazer]

Yep, that's it.

[Kampz69]

cool, thanks

[Kampz69]

it looks like you have to use the fuel injection (spider) connector from the v8, correct? the v8 connector looks longer and runs front to back on the intake compared to side to side on teh v6 intake. probably a dumb question, but i wasnt sure if the v6 connector was the same, but just had two empty slots for the fuel injector wiring.

[Kampz69]

nevermind, they are different (and not cheap to buy new lol). so ill need the injector pod connector, or preferably one and its wiring from a v8 engine harness...that seems the easiest way.

[nonstop]

I've got some pics of the injector harness you guys are talking about in my sig...Just finished my L31 swap...well on going...because now I'm putting in my second corvette rad. Leaking for some reason, manf defect?? Oh and i recommend moving your rad forward and running the stock 4.3 fan, my electric fan could never keep up but the mech fan 160 to 180 all day.

May be against the rules but v8s10.org has tons of info, its how i got through my swap.

[03blazer]

I just pulled the injector plug and wiring out of the harness from the truck I got my engine out of. I'm gonna find another 4.3 wiring harness to modify so I don't have to cut mine up just in case something doesn't go as planned...

[Kampz69]

i didnt think the mechanical fan would work even with the rad moved forward...hmm

[03blazer]

Yeah, it'll fit. Look at the truck that's on JTR's website.

[Kampz69]

so it will...hmm that would completely defeat the purpose of me wanting to convert to a 01+ ECM since there would be no efan to control. ive sifted that site before, i must not have seen that pic...thanks for pointing it out to me.

[03blazer]

When I do mine, I'm probably gonna run some LS1 e-fans with a 'Vette radiator forward mounted. Gonna run all the wiring through the harness.

My uncle has a wrecked Blazer that I'm gonna use to mach up all my stuff before I do my swap. Gonna get it all set up in that before I swap it all over to mine. It was rolled so the only thing that was hurt was the roof was crushed in. Should make my swap a lot easier.

I have a stock Vortec 350 that I know runs that I'm gonna put in my truck until I get my 383 built. I'm ready to get home from deployment so I can get started on it...

[Kampz69]

i would do the same if this was my daily, but if i do go through with the engine swap, it will become a winter beater/plow vehicle. i would actually like to convert it to a manual transfer case to get rid of the shady encoder motor and vacuum actuator.

just need to find a good price on a plow lol

[03blazer]

Yeah, mine is my daily. I have my Eclipse I can drive while I'm working on my truck though.

[Kampz69]

of course my good blazer crapped out today (fuel pump im guessing, it cranks but doesnt start) on the way to work, so now i get to work on that. too bad i didnt have the swap done in my other blazer lol

[03blazer]

Hah, that sucks. I'm waiting for my wife to call me and tell me the pump went out on mine. It was making noise before I left for deployment. She's been driving my Blazer while I'm gone.

Lol, can you picture a 5' tall, 95lb, Filipino girl driving a loud ass Blazer??? I can't... She never drives it when I'm home....

[Kampz69]

LOL, no i cant picture that....thats hilarious. i found a bosch replacement pump for 220 shipped, now i just need to make sure its really the fuel pump before i buy anything.

[03blazer]

Yeah that would probably be a good idea...

[Kampz69]

it is the entire assembly, i made a couple calls last night. for reference to anyone looking for one, its bosch #67378. i think it fits 98-01 4 doors...

[woohoooo964x4]

so what about emissions codes on the 350 vortec swap. would the obd2 still read like it was supposed to?

[Kampz69]

with the computer tuned properly, yes

[V8Sonoma96]

Does anyone know if 96 4.3 harness and 97 4.3 harness are the same?

[Kampz69]

id guess they were very similar, but i cant say for sure.

[91sonomast]

I like this sticky, really wish my Blazer was paid off, I could justify doing this more.
With the new updated injectors, with a system like EFIlive or HPTuners, can you change the injector firing time and length? Like for a bigger cam so it will idle properly and make the most horsepower from the cam? That is one big thing that sells me on the LSx, is the tuning capability, you can run as big of a cam as you want because you can program the injectors. I wouldn't want to run a HUGE cam, but one big enough that you could tell it had a bigger cam in it. I like my Blazer, but if I can sell it, I see me buying a shitbanger for a DD, and finding a cosmetically good, 98+ ext. cab with a 4.3 and doing this swap. Maybe with any luck I can find one with a blown engine or something and get a real good deal on it.

[carter]

Quote: Originally Posted by 91sonomast

I like this sticky, really wish my Blazer was paid off, I could justify doing this more.
With the new updated injectors, with a system like EFIlive or HPTuners, can you change the injector firing time and length? Like for a bigger cam so it will idle properly and make the most horsepower from the cam? That is one big thing that sells me on the LSx, is the tuning capability, you can run as big of a cam as you want because you can program the injectors. I wouldn't want to run a HUGE cam, but one big enough that you could tell it had a bigger cam in it. I like my Blazer, but if I can sell it, I see me buying a shitbanger for a DD, and finding a cosmetically good, 98+ ext. cab with a 4.3 and doing this swap. Maybe with any luck I can find one with a blown engine or something and get a real good deal on it.

I hear yea...and with the vortec your choice of cams is pretty limited. I'm looking at doing an LSx swap in the future...im getting greedy, the main reason i swapped was to have a really nice sounding truck...and now I am after more power even though: i'll never race, I'll never abuse it, I'll never go over 130 km/h - It's just so i can say ya...its 400 HP lol. Basicly if your power hungry go with the LSx...if your like me and just want a nice sounding truck and improved gas millage and not all worried about power then go with the vortec 5.7L.

[Kampz69]

the LSx will get better mileage and have more power...the vortec swap is far easier though lol

[carter]

If you have everything id say their about equally difficult. The vortec swap is far cheaper though