Thread: 3800 SC III swap... What do I need to salvage?

I have a great deal on a 3800 SC III out of a 2004 Grand Prix GTP. It comes with all of the accessories and anything else I want at the price. I am planning to swap this engine into a Fiero. I know that you guys aren't Fiero experts (I'm on the Fiero forums too), but I have a few specific questions concerning the 3800 SC III.

Do I need anything else besides the engine, wiring harness, and ECU for a fully working engine??

What's the deal with the drive-by-wire throttle? Do I need to salvage the gas pedal for that? Can I just scrap the drive-by-wire and use a plain old cable?

I'd like to upgrade to the Grand Prix's cruise control. What do I need to make this happen?

Can I remove the part (sensor) of the pedal assembly for the GTP that makes it TBW and put it on my Fiero gas pedal? I'm going with a manual transmission, so only the brake pedal won't fit, there's no clutch pedal, and the gas pedal may be a different length.

If I can swap the sensor, I'll probably do that. If not, I'll probably convert it to non-TBW.

btw, is TBW only for traction control/cruise control, or does it have a real performance use?

Someone wrote this on the Fiero forums. What can you guys tell me about it?

Regarding the series III it can be a tricky installation. We avoided it by going with a late series II PCM and converting to a cable operated TB with an LS1 MAF sensor.
Two different ETC systems aree used today. One is "torque follower" (the current version of ETC) the other is pedal follower that is an earlier version. The 3800SC series III is torque follower and very sensitive to the slightest engine modifications. Therefore new engine calibrations must be done for a Torque based ETC to work properly. Modifying the engines exhaust, or adding accesories to increase power changes the relationship between engine power and and throttle position. Torque based ETC systems often recognise extra power as a fault and will trigger "limp home" mode if the change is larger than about 5%. Also transmisson controls also affect torque output so again be prepared for a more complex PCM reprogramming if you chose to go drive by wire. It's been done before but it is harder than a series II swap.

I will be doing a power steering delete (Fieros don't have power steering), new exhaust and cold air intake... that's probably 10+% more power... would trigger the "limp home" mode. Plus, I'm not using the Grand Prix's transmission. Should I just screw it and do the Series II conversion (what's up with the MAF?)?

Originally Posted by Rolling Thunder

Someone wrote this on the Fiero forums. What can you guys tell me about it?



I will be doing a power steering delete (Fieros don't have power steering), new exhaust and cold air intake... that's probably 10+% more power... would trigger the "limp home" mode. Plus, I'm not using the Grand Prix's transmission. Should I just screw it and do the Series II conversion (what's up with the MAF?)?

Do a series II swap. That is the 97-03 stuff I was talking about. Just swap over EVERYTHING (compleate engine wiring harness ect) from any 97-03 gtp and be done with it. With this you will be using the throttle body that is dependant upon a cable for movement. You will have to do nothing to the MAF. It will be bennefictial if you do some tuning to the MAF if you get a cold air intake becuase they can change the trims becuase of the Colder air. It should still run fine without it.

The maf is located in the TB of all 97-03 model 3800 engines.


Regarding the ls1 TB they were talking about- You can actually modify a LS1 TB to work on our cars. I will find the link on how to do this in a second.

Thanks Jason again for this usefull post.

Originally Posted by GR8racingfool

MY LS1 TB pictures:

How it sits stock:


The press fit bond was ground off the shaft. now your free to remove the CRUISE control cable bracket, and the throttle cable bracket.



Reinstall them, "flipped" which is needed for both GenIII and GenV M90 set ups regardless if the TB is sitting vertical, (for the GenIII's) or flipped/inverted (for the GenV's).



Now make your best attempt at welding them back on/together onto the shaft they sit on.



I suck at welding, but its still holding strong, so who cares ya know.

Install:




This was my custom made GenIII billet aluminum plate, and the first ever and only one ever made, billet cable hanger was on this one. (which was sold to a good friend when I went GenV)


I'll see if I can find some pictures of my GenV LS1 pictures.

~F~

Originally Posted by TDCRacing

And If you use a non drive by wire TB then you will need the gen 5 to gen 3 TB adapter.

What I ment by this is the 04+ motors that are supercharged(non supercharged are the same bolt pattern for the TB) , Use DBW TB's. The DBW TB's have a different ''bolt pattern'' than the 97-03 TB's. The same applies for the superchargers. If you use a 04+ supercharger (wich comes with a DBW TB) (the o4+ S/C's are more effecient BTW) with a 97-03 TB then you would need the adapter plate (runs about 80 bucks) so you could make them bolt up.


A lot of people use a Gen5 (wich is an 04+ supercharger) on their 97-03 cars and replace their Gen3 (97-03 superchargers) becuase the Gen5 is like I said a more effecient supercharger.


If you need any other help or something I said is not making sence (imagine that lol) then let me know and we will go over it untill it does.

Ok, the things you are explaining I already know. That is good. It means that I'm up to speed and that you guys are steering me in the right direction.

Ok, so DBW is out and Series II is in right?

If so, is there any downside to doing the LS1 throttle body (like cruise control or throttle position sensor not working)?

Since it is supercharged and it will pull the air in, will the LS1 throttle body over the Series II throttle body actually make a difference?

Is the Series II adapter just an aluminum plate with holes in it for you to bolt to? If so, I can make that myself since the tolerances are probably in the hundredths of an inch. (I have access to a machine shop)

Originally Posted by Rolling Thunder

Ok, the things you are explaining I already know. That is good. It means that I'm up to speed and that you guys are steering me in the right direction.

Ok, so DBW is out and Series II is in right?

If so, is there any downside to doing the LS1 throttle body (like cruise control or throttle position sensor not working)?

Since it is supercharged and it will pull the air in, will the LS1 throttle body over the Series II throttle body actually make a difference?

Is the Series II adapter just an aluminum plate with holes in it for you to bolt to? If so, I can make that myself since the tolerances are probably in the hundredths of an inch. (I have access to a machine shop)

I would say so. You can retain the cruise on a ls1 TB swap. If you are not planning on doing much to the engine then the stock one will be fine. You will get a little better throttle response out af a bigger throttle body but not really worth it for what you have to do.

You start needing a bigger throttle body when you start adding headers smaller pulley ect ect. Then you don't have to have one but at that point it would become bennefictial to you. You also have the option to port you stock one and take the ''hump'' out of it. Wich will improve it.


Basicly it is a flat peice of aluminum with aprox. a 75mm opening and the bolt holes are countersunk. That then bolts to the gen5. Then the correct bolt pattern is made so the non DBW TB can be bolted to that. The holes are countersunk so that there are no issues with it sealing.

But you don't need one enless you have a Gen5

Originally Posted by TDCRacing

But you don't need one enless you have a Gen5

Gen5 throttle body or Gen5 supercharger? I thought we were adapting the Series II throttle body to fit.

You said you were going with a 97-03 setup (series 2) So unless you put a gen 5 supercharger on and replace the gen 3 that is on there now (theses have the DBW TB that have a different bolt pattern that the 97-03 TB's) then you don't need to have an adapted plate.


If you're going to be using a 97-03 setup you can use everything...TB and all. Everything already fits and is designed to work. The adapter plate only bolts up a 97-03 TB to a 04+ supercharger wich utilizes the DBW TB.

Ok, I guess all this Gen 3/5, Series II/III, etc talk got both of confused, lol. I'm doing the SC III. I'm keeping the Gen 5 SC. I'm going to downgrade the necessary parts to use a cable throttle. This means the wiring harness, ECU, and throttle body. Is this right?

btw, it's being delivered on Monday. To have it delivered to me, I'm paying $1200 for the engine (has all accessories and only 70k miles), trans (G Comp package with shift paddles), wiring harness, ECU, BCM, PK3, ignition, and key. Is there anything there that I'm missing from the Grand Prix (I gotta defeat the VATS)?

Use the OBD1 or (97-99) OBD2 computer, and just have Ryan at GMtuners.com bypass VATS for you and do a base tune. You'll need the OBD2 computer to use the 65E-HD trans. Working with a post 2003 computer is absurd. There's also no specific need to use a Series III computer, so go with the old school electronics. Old wiring, new motor with better supercharger and rods.

Also, just buy the ZZP TB adapter for the N* or LS1 TB for the GenV charger and be done with drive by wire.

ZZ Performance
ZZ Performance

btw guys, I'm about to have a the following G Comp package for sale:

4T65HD-E (70k miles)
Series III wiring harness
Series III ECU
Steering Column (with paddle shifters)

Should I stick with the Passkey/VATS system for the added security? I wouldn't be opposed to added security.

Can you guys help me out? The seller needs to know where/what the bcm and pk3 are so that he can give them to me. Can you guys get me some pictures?

(all I need are the bcm, pk3, ecu, and ignition to make passkey/VATS work right?)

New to the site, and am in the same situation. My last swap was a series II from a 98 Bonneville SSEI into a rock buggy. I picked up a series III today not realizing it was drive by wire. Trying to make sure I have everything, as I'd prefer to keep the better SC, but run dbc over dbw. If there's anything specific I need beyond what's posted, please let me know.