19 replies to this topic

[bubba68ss]

Will emissions notice that it has a v8? All they do now to test is plug something in to the OBDII port and test the gas cap. Assuming it runs as it should and I'm not getting codes, this should pass the test right?

What should I have done to the computer? Should I buy a used computer and send it away so it will just be ready to plug in? Is that a good idea?

What do I ask them to do to the computer? It is a 5-speed, does that make a difference? What about the 'pass lock' that I hear about?

Should I get a harness with the engine if possible? If not, did I read right that I can just add a few injector wires and be good?

Will stock manifolds work if they come with the engine? If not, which headers should I get?

I need a crankshaft relearn done, but it will still run without, right?

I want this to be a budget build and I plan on a max of $2000.

[BLACK96regcabHighrider]

Will emissions notice that it has a v8? All they do now to test is plug something in to the OBDII port and test the gas cap. Assuming it runs as it should and I'm not getting codes, this should pass the test right?

What should I have done to the computer? Should I buy a used computer and send it away so it will just be ready to plug in? Is that a good idea?

What do I ask them to do to the computer? It is a 5-speed, does that make a difference? What about the 'pass lock' that I hear about?

Should I get a harness with the engine if possible? If not, did I read right that I can just add a few injector wires and be good?

Will stock manifolds work if they come with the engine? If not, which headers should I get?

I need a crankshaft relearn done, but it will still run without, right?

I want this to be a budget build and I plan on a max of $2000.

Not 100% sure on what has to be done to keep it emissions legal, I know someone on here has kept it emissions legal. I know you will need to keep your evap, all o2's, and egr.

As far as the computer, send it somewhere who has had experience tuning them for the specific swap. I sent mine to fastchip, he screwed up the first time, but stood behind his work and got it right the second time. I got the computer back the same week I shipped it. You could get another computer if you want, just make sure its the right one, there's a couple different black boxes if that's the one you have. I have an extra black box comp sitting in the garage, if it's the right one and you want it before the swap, let me know and I'll sell it cheap.

There's a form you fill out with vehicle/engine specifications (transmission is included on it).

Keep your 4.3 harness, either modify it yourself, or send it to Current Performance Wiring (CPW). I sent mine out, but from what I've read, 98+ are easy to wire yourself.

Stock manifolds will not work. I went with Patriot s10 conversion headers because they were cheap, get the ceramic coated if you can. If you do in fact need to keep your egr, you will need to have it plumbed into the drivers side header.

Yes, it will run without a crank relearn, it just wont run as well as it should depending on how far off you are. Fine to drive to a shop without it done.

$2000 budget is dooable, depends on how much you spend on a motor and if it needs work.

[bubba68ss]

I found a complete 5.7 from a 99 suburban (says its a crate motor) but has a cracked head. Does that mean it was overheated? Are those heads easy to come by?

[BLACK96regcabHighrider]

I found a complete 5.7 from a 99 suburban (says its a crate motor) but has a cracked head. Does that mean it was overheated? Are those heads easy to come by?

The engine shop that worked on mine said the vortec heads are known to crack when overheated, they see a lot of them. Scarcity depends on your area I would suppose. I've seen them on craigslist around here from time to time. Since people are using the LS motors more now, I don't think it would be hard to find another head.

[civicslayr07]

Will emissions notice that it has a v8? All they do now to test is plug something in to the OBDII port and test the gas cap. Assuming it runs as it should and I'm not getting codes, this should pass the test right?

What should I have done to the computer? Should I buy a used computer and send it away so it will just be ready to plug in? Is that a good idea?

What do I ask them to do to the computer? It is a 5-speed, does that make a difference? What about the 'pass lock' that I hear about?

Should I get a harness with the engine if possible? If not, did I read right that I can just add a few injector wires and be good?

Will stock manifolds work if they come with the engine? If not, which headers should I get?

I need a crankshaft relearn done, but it will still run without, right?

I want this to be a budget build and I plan on a max of $2000.

Not 100% sure on what has to be done to keep it emissions legal, I know someone on here has kept it emissions legal. I know you will need to keep your evap, all o2's, and egr.

As far as the computer, send it somewhere who has had experience tuning them for the specific swap. I sent mine to fastchip, he screwed up the first time, but stood behind his work and got it right the second time. I got the computer back the same week I shipped it. You could get another computer if you want, just make sure its the right one, there's a couple different black boxes if that's the one you have. I have an extra black box comp sitting in the garage, if it's the right one and you want it before the swap, let me know and I'll sell it cheap.

There's a form you fill out with vehicle/engine specifications (transmission is included on it).

Keep your 4.3 harness, either modify it yourself, or send it to Current Performance Wiring (CPW). I sent mine out, but from what I've read, 98+ are easy to wire yourself.

Stock manifolds will not work. I went with Patriot s10 conversion headers because they were cheap, get the ceramic coated if you can. If you do in fact need to keep your egr, you will need to have it plumbed into the drivers side header.

Yes, it will run without a crank relearn, it just wont run as well as it should depending on how far off you are. Fine to drive to a shop without it done.

$2000 budget is doable, depends on how much you spend on a motor and if it needs work.

Headers- stock will not work due to steering shaft clearance. i used 4x4 350 headers for a box body style s10.

crank relearn- never did it... never will if your an old school guy that knows how to twist a distributor your fine... the crank relearn just puts it dead on vs. being a half of a degree off... our distributors are locked in more or less but there is wiggle room. i run mine advanced.

budget- it can be done for 2k but you will not be happy, also im at 6k just puttin that out there.

ecu- mine was tuned by wait4me... no issues

harness- its 2 extra wires... not worth the arm and leg you have to send away to have it made for you, and your budget wont allow for it.

emissions- i searched and searched. i live in md... our emissions are unreal compared to some of the stories i hear. my truck is running egr delete, rear o2 delete and a glasspack. i have yet to put it through emissions because ive been to bust with my honda but i know it will pass. as long as you have no check engine and you have a good cat your fine.

[bubba68ss]

I am getting more serious about this swap. I am still unclear about a few things. Will my donor computer work as just a plug and play? I am assuming not but want to be sure. Also, when emissions plugs in to OBD II port, does it say what kind of engine is in the truck? Does the computer say it's a tahoe motor? Or do they just look for CEL's?

[6speedblazer]

I cant speak on your state but here in Missouri with "plug in emission" the inspector is supposed to cross reference the vin on the dash with the vin inside the PCM. He even has to take a picture of the VIN plate and upload it to the inspection server along with the computer generated pass/fail report.

BUT you can easily get around that by using a reputable tuner.

What they need to do is take your stock tune with the VIN from your truck/engine and segment in all the 5.7L engine calibrations. That will leave your VIN "stock" and make the engine run

[6speedblazer]

crank relearn- never did it... never will if your an old school guy that knows how to twist a distributor your fine... the crank relearn just puts it dead on vs. being a half of a degree off... our distributors are locked in more or less but there is wiggle room. i run mine advanced.

You obviously have no idea what a crank relearn is...

please read the following link before you try and give advice.

http://www.trifectap...rankrelearn.htm

[6speedblazer]

Here is a link on how to use stock manifolds. I dont know if it will work, but it looks promising. I have pictures in my photobucket somewhere where i compared swap headers to the stock manifolds i took of my motor, it looked close.

I i ever get around to doing a swap on my truck i plan on trying this. Only thing i would do differently is either machine the bolt flance to match the new angle or machine an angled "washer" to correct the angle.

http://www.s10forum....zer-awd-432685/

Edited by 6speedblazer, 17 August 2012 - 05:40 AM.

[bubba68ss]

Here is a link on how to use stock manifolds. I dont know if it will work, but it looks promising. I have pictures in my photobucket somewhere where i compared swap headers to the stock manifolds i took of my motor, it looked close.

I i ever get around to doing a swap on my truck i plan on trying this. Only thing i would do differently is either machine the bolt flance to match the new angle or machine an angled "washer" to correct the angle.

http://www.s10forum....zer-awd-432685/

Good idea and I may try it.

[bubba68ss]

Picking this 5.7 up on Mon for $450. Comes with complete gasket kit, harness and computer.



Have i read right that it is best to use the stock computer and just alter the fuel injection management?

[6speedblazer]

Picking this 5.7 up on Mon for $450. Comes with complete gasket kit, harness and computer.



Have i read right that it is best to use the stock computer and just alter the fuel injection management?

its my personal opinion that using the stock computer is best. But you know what they say about opinions.

[GreenChevelleSS]

I found it easiest on the knock sensor to just drill and tap where the original 4.3L one was and just put a plug where the 5.7L should be. I also used the 5.7L knock sensor, the block drilled and tapped alot easier than I thought it would.

[bubba68ss]

Apparently my local PCM guy could not read the 96 black box from the tahoe, but my 99 read fine. He sent me the .tun file of my computer and his registration key to efilive ( I can only read and edit, not flash without the gear). It is pretty fun looking through all the stuff to change. I need to find a 99-2000 5.7 stock code so we can copy over the engine management segment. From what I have researched, that is all that has to be changed. I just met the guy tonight, he does this in his spare time and is local. He is up for helping me until everything is working right. I am quoted about $275 to do everything, that may be high but again, he is local and there is no shipping. Plus he can come to my house.

Praying everything goes smooth (for once). Block is being prepped right now, ordered the advance adapters mounts and will get the patriot headers I believe. Also need to get a spare car lined up while my truck is out.

Does anyone know if messing with EGR delete will show up when emissions plug into my OBDII? They don't visually check anything. I THINK they just look for codes. In fact, is there ANYTHING that I just shouldn't mess with when tuning? VATS has no effect on internal security (alarm, door locks, etc), right?

Edited by bubba68ss, 23 August 2012 - 02:39 AM.

[bubba68ss]

machine shop said one of the heads is visibly cracked. for fux sake. I hope the damn block isn't too.

I have to find some good cores... don't know about the other head because they havent tanked it yet. Found a set off a 96 tahoe, still on motor, bottom end went out. They want 125 each. Is that too much?

Edited by bubba68ss, 23 August 2012 - 09:26 PM.

[BLACK96regcabHighrider]

I would try to get them down some more. I just did a quick local craigslist search and found two pairs of heads. One was $100 firm for both, the other was make offer.

Especially for a set of heads that you're going to be machinging anyway. But if that's what they go for there, thats what they go for.

My shop was surprised when my heads with 270,000 miles had no cracks. I was told it's common for the 5.7 vortec heads to crack from high heat.

[rczr2]

I found it easiest on the knock sensor to just drill and tap where the original 4.3L one was and just put a plug where the 5.7L should be. I also used the 5.7L knock sensor, the block drilled and tapped alot easier than I thought it would.

Do you recall the size of that tap by chance? I'm thinking I'd rather go this way as well. And when you say that you used the 5.7 sensor do you mean that you used it in the hole you tapped where the 4.3 on was? Is there even a difference between the two?

[rczr2]

Does anyone know if messing with EGR delete will show up when emissions plug into my OBDII? They don't visually check anything. I THINK they just look for codes. In fact, is there ANYTHING that I just shouldn't mess with when tuning? VATS has no effect on internal security (alarm, door locks, etc), right?

Vats will not change anything on the interior workings of your truck. as far as I know the removing vats is only necessary because the vin number for the PCM and the bcm needs to match in order for you to get fuel and spark. I think you could actually have your vin reprogrammed into the new PCM and leave vats, but I could be wrong there.

I wouldn't worry about emissions. On the technical Side of things putting anything into your truck other than factory emissions equipment will make it emissions illegal. That being said most states emissions testing only require 3 things. 1 no obd2 codes set within the last cycle on your PCM. 2. Evap emissions control system function ( gas cap seal) 3. Tailpipe gasses must be within whatever they specify as the acceptable range. 9x out of 10 they won't even pop your hood or even know what they were looking at if they did. The only way I see them knowing anything was up is if their scanner were able to look at individual I/O's for each sensor. Even then you can feed a false signal to make it appear that everything is there and working.

If being legal is your biggest concern build your swap to California standards. Theirs are the toughest to get around and usually the most talked about as far as engine swaps are concerned. A quick google search should net you all the info you want.

[GreenChevelleSS]

I found it easiest on the knock sensor to just drill and tap where the original 4.3L one was and just put a plug where the 5.7L should be. I also used the 5.7L knock sensor, the block drilled and tapped alot easier than I thought it would.

Do you recall the size of that tap by chance? I'm thinking I'd rather go this way as well. And when you say that you used the 5.7 sensor do you mean that you used it in the hole you tapped where the 4.3 on was? Is there even a difference between the two?

I think it was a 5/16 or 1/4 NPT pipe tap.

[LS2Sonoma]

.. 1/4 NPT pipe tap.