: 3800 Supercharged V6 in a Catera

01-28-08, 08:54 PM
I am currently working on a 1997 Catera that is stock. Being unhappy with its peformance, I started looking for a good, reliable and inexpensive replacement engine. Yes, I would like an LS 1 but it is beyond my budget.

I bought a 1998 3800 Supercharged V6 from a Buick Regal on eBay for $500. I then realized I needed a front sump oilpan. A Holden Commodore, VT series, has a 3800 as the standard engine. A bought an oilpan of eBay for $70 including shipping. See the photos comparing it to a stock 3.0 Catera oilpan.



See the oilpan installed on the engine:

In this configuration, you must use the rear most set of motor mounting holes which places it were the stock 3.0 sits.


The A/C compressor is in the same location as the stock 3.0, so minimal adapting.

The wiring is Holden VT as well as the ECU.

01-28-08, 09:55 PM
Very nice project keep us in the loop on all progress and pics as well as ALL supplys and modifications needed as many people would love to do this project after you keep up the good work best of luck

Po Pimp
01-29-08, 07:00 PM
Where did you get the computer?
How much did it cost?

The L67s are a dime a dozen around here, same with the L26s and L36s.

To bad the mounts are different from the earlier versions. It would be nice to get a 3.8L or 4.1L and do it like a Buick GNX.

01-29-08, 07:47 PM
sweet looking forward to seeing how it turns out.

how about tranny? I'm assuming you're gona change that up

01-29-08, 08:23 PM
I got the computer off eBay. The ECU (ECM in the US) cost me $50 with shipping. I bought the Engine harness for $70 with shipping.

The Holden Commodore VT series has a 4L60e, so the best donoer will be a V6 Camaro / Firebird. The computer system is like the pre OBDII GM, so it still has a chip (Memcal -in Australia) and there are many modifies chips available.

The other thing is the VT has the Sport/ Economy mode, the electrical valving in the power steering and TC/ABS are very similar.

I will have to move the battery to the opposite side and put the airbox on the driver's side.

The radiator will have to have the tanks on the opposite side - upper / passenger side - lower driver's side- which is how the Holden is anyway.

One horsepower maker will be the real dual exhaust the Catera has, the Holden doesn't and no other production L67 either.

01-29-08, 08:54 PM
so far you have $50 dollar computer $70 wring harness $500 for motor and $70 for oil pan and your looking for a transmission from v6 camaro
so your at about $700 with out tranny right? thats not to bad

01-29-08, 08:58 PM
wow...that's great resourcing...i looked up the engine and couldn't find any numbers on it. I suppose it has 210HP minimum, and supercharger should add atleast 20-50HP, right? One more thing..is it a 3800I, II, or III? Good luck with it!

Po Pimp
01-29-08, 09:37 PM

Generation II (engine code L-67)
255 bHP @ 4600 rpms
280 ft-lbs @ 2500 rpms
1/4 mile ETA @ 14.7s
0-60 MPH in 6.6s

The specs above are from the car it came out of. It will differ after it has been installed. With some of the chip options it has or you could even probably buy a programer to do it yourself, you tweak it for more. As SC said the exhaust that is on the Catera is superior then what it would have gotten stock, so potentially more power there. You can change some of the internals as well and get more power from the engine. Also you could run more boost. The engine has quite a bit of potential. The transmission can handle around 350 ft-lbs of torque.

On the transmission subject anyone who may be thinking about the conversion should look into the transmission they are getting. There have well know valve body problems. It would probably be advisable to deal with this before it gets in the car. Many fix kits out on the market for the trannies problems. Not a huge deal or anything with the tranny but something that should probably be mentioned.

Po Pimp
01-29-08, 09:39 PM
Not sure what happened here?

01-29-08, 09:39 PM
It is a series II. It was rated at 240 HP and 280 pounds of torque. Add a smaller supercharger pulley and it adds about 25-30 HP, factory duals on the Catera, fabbed headers and a Cold air intake should put in the 300 HP range. 300 HP with a 3.91 geared rear may = Mid 13's in the 1/4. Minimal mods on a GTP Grand Prixs are in the high 12's.

Another reason for the 3800 Sc is durability. My in-laws have a 1998 Regal GS that has 190,000 miles that has had only tune ups and a waterpump.

The whole idea of building the Catera this way is if it was a factory built car. I have the emission decals and have the supercharged emblem of a Regal to go on the trunk opposite of the Catera emblem.

Another mod that is real cost effective is running 235/55 - 16 tires. They fill the fender well better, only affect the speedo by about 2.5 MPH at 65 and there is alot more less expensive tires to chose from.

01-29-08, 09:42 PM
Your right on the trans. I have heard of putting a Corvette Servo in and it is suppose to improve the shift quality. Best of all, I have seen them for about $35.

01-30-08, 12:09 AM
Did the Holden have an PCM that operator both the engine and transmission. Or did it have a separate ECM and TCM?

Also did you consider going with a manual trans? The Camaro V6 was avaiable with a 5-speed. You would just have to buy the pedals, slave cylinder and a few other parts from Europe. I already have bought these parts for my LS3 + T56 conversion.

01-30-08, 03:27 PM
sounds like you got this thing down...all you need is the parts. I'm also lovin' the potential 300HP!

01-30-08, 07:09 PM
The ECU controls the engine and transmission. You can get modified chips from Australia to modify the boost, ect.

I have considered the manual, but in the intrest of money, I decided to go with the auto. You can buy a 4L60E for a V6 relatively cheap.

I have the Holden shop manual and have started tracking wires that need to stay what needs to go from the Catera harness.

I also made the passenger side proto type engine mount to retain the stock Cadillac engine mounts. I will post a photo soon.

01-30-08, 08:22 PM
Years ago I bought an '88 VN Commodore with the 3.8 and thought it was a bit of a dog. The Nissan I6 in the VL was a much better combo especially with the turbo but both of those motors blow the 3.0 in the Catera out of the water. The Nissan had more power and liked to rev, the Buick engine was decent.
Now add a blower and it could get fun.

Keep us posted on your project, I think you picked the right combo.

Instead of rebuilding my Cat motor I should have thrown a 3.8 in there.:thepan:

01-30-08, 09:43 PM
Well, I put one motor in mine. The original motor had blow a head gasket (surprise!) prior to me purchasing it. By the time I got it, water hasd ruined 4 cylinders. I priced over sized pistons and they were about $125 a piece. I just bought another motor instead. While I had it out, I saw how much room there was and decided to plan ahead for the next engine.

Here are 2 photos of the right motor mount prototype made from scrap steel:



It is relatively simple mount. The left side, I have designed but not made yet. It will be more complicated due to having the starter in the way.

01-31-08, 07:52 PM
I truly admire people like you who can build a car from scratch.

Those 3800s are almost bullet proof. Alternator once in a while. Vibration dampener at about 60k miles. Superchargers seem to fail at about 36k miles on many cars (and brand). One GM mechanic told me that if the owner of a supercharger fails to check/add oil in it after 24k miles, it will go out. ???

Trannies are strong too. I hear that the torque convertor lock up switch fails on some of them, but I think that is easy to get to.

Good luck. Keep us posted.

Good luck.

01-31-08, 09:39 PM
Thanks, I appreciate the luck. I hope to make it appear and function as close to being factory installed as possible. I have done engine swap before. See the photo of my 1985 Trans Am with a big block Chevrolet engine.Everything is functional and factory style:

Here is what I am after.This is the factory Holden with a 3800 SC:

The biggest problem so far has been interpreting wiring between the cars But I will figure out somehow.

02-04-08, 10:08 PM
any updates??

02-05-08, 07:43 AM
I purchased another Catera that has rear body damage over the weekend so I could use it for parts and a test mule for fitting the engine. That way when I get it all done, all I have to do is swap it and there will be less surprises. I got a factory Holden airbox amd SC throttlebody comming. I also have started working on the radiator set up. It appears from measurements that a 182-1992 camaro radiator core with 1995-1999 Oldsmobile side tanks may be the closest fit with factory apearance and function.

02-05-08, 09:52 AM
wow man you got it all figured out what do you estimate the total cost of project to be? motor, tranny, wiring ,etc?

02-05-08, 05:34 PM
I figure no more that $1500 - $1750 to do the complete the swap. I still have to get the mass air flow sensor. The Holden version uses a seperate throttlebody and MAF sensor. I also need to get a transmission from a Camaro / Firebird for the trans upgrade.

02-05-08, 05:38 PM
I see well please keep track of everything as i may be interested in the swap and i know a fabrication guy so if you tell us exactly what is needed when your done you can be the pioneer of the 300 hp catera project =)

02-05-08, 05:56 PM
OK, I have been trying to keep up with the make and model of all parts I have been using. I have been trying to make this as painless as possible so other may follow if they so chose.

02-05-08, 06:40 PM
I purchased another Catera that has rear body damage over the weekend so I could use it for parts

What are your plans for the motor mounts and the tranny mount out of that car ?
If they are decent and you don't need them I would gladly buy them.

02-05-08, 07:20 PM
As soon as I get the motor and trans out, I will see what kind of shape their in and let you know.

02-05-08, 07:41 PM
That would be great, thank you.

How are you getting the parts from Aussie ?
Through ebay or do you have a hook up ?

02-05-08, 08:56 PM
I been getting the parts on eBay. The only problem is some people won't ship outside of Australia. If you choose to buy something, have it shipped Sea mail, it take about 8 weeks but it is much more reasonable to ship. One cool thing I found is if you use a HSV spec prom (Holden Special Vehicles) it will raise the standard hp from 240 to 255 before any other mods. 300 hp is becoming a reality.

02-06-08, 05:32 PM
If you ever have trouble getting stuff shipped from Aussie I can give you a local address.
Have a bunch of family over there.

02-06-08, 07:40 PM
That would be great. I may have to take you up on that!

02-06-08, 08:08 PM
Any time.

If there's a "hard to find" part you need from Holden I may be able to help wit that.
Used to work at a dealership and my dad is still big into the HSV vehicles.

02-20-08, 07:17 PM
Any updates on the build? (bump to the top)

02-20-08, 08:08 PM
Here is a V8 BMW swap in a Station Wagon.... pretty bad ass if you ask me...:lildevil:

V8 Omega Swap (http://youtube.com/watch?v=b0hjHHgGkEY):cookoo:

02-20-08, 08:38 PM
I just got my "test mule" Catera home. I will be test fitting the engine and running the wiring in it while I keep my other one running. I also have the Holden V6 exhaust manifolds and air box comming. I have started modifying the Holden engine / ECU harness to work with Catera wiring. I will post some more photos soon. While I have the mule, I will be seeing what else will fit for laughs.

02-20-08, 11:43 PM
I been getting the parts on eBay. The only problem is some people won't ship outside of Australia. If you choose to buy something, have it shipped Sea mail, it take about 8 weeks but it is much more reasonable to ship. One cool thing I found is if you use a HSV spec prom (Holden Special Vehicles) it will raise the standard hp from 240 to 255 before any other mods. 300 hp is becoming a reality.

Modifying Grand Prix GTP's is quite popular here in North America and many companies offer PCM trunes. You'll probably save more money than buying it from Australia.

02-22-08, 09:14 AM
I own a 97 GTP and have been a member of a couple grand prix clubs for several years now...if you have any questions the L67, then let me know. (if I can't help, I might know someone who can)

I also own an 85 fiero...I plan on doing an engine swap with that car and my 3800sc.

03-03-08, 02:33 PM

03-03-08, 07:51 PM
I got the factory exhaust manifolds coming from Australia. They are from a SC 3800 Holden VT. I also started dismantling my parts Catera to start test fitting parts. I have located where the ECM will be and how to run the harness. I will post photos soon.

03-03-08, 10:43 PM
sounds good i buumped it htought you forgot about us haha :D

03-19-08, 09:53 PM
Just got my GTO brake calipers from eBay. I paid $37.00 with shipping for the calipers and rotors. Can't use the rotors. I test fit them on my test mule.

Here is the stock Catera brakes

Here is the 2004 GTO brakes.They fit a 97 also and fit under stock 16 inch wheels.



Now I have work on putting it on the real car.

04-14-08, 02:32 PM
I'm getting pretty close to doing the same exact swap, where are you located? I would love to pick your brain a few times to make my swap go as easy as possible. Would the traction control and abs still function? Thanks, Brent

04-14-08, 05:28 PM
I am located north of Atlanta, Ga. The abs will still function and the traction control should. If it doesn't I will get the Holden Commodore ABS and adapt it. PM me and I will give you my regular email address.

04-14-08, 06:13 PM
I only have 18 post so It wont let me... But I will work on that and in the mean time I will just ask you if you would attempt to do the same swap for me if I brought you the car and parts... well and a bag of money...? I'm kicking around a few shops to do it right now and dont think they would quite have the grasp of it as someone like your self. I'm in Nashville and could work out the details of shipping as I am a logistics Broker. Let me know your thoughts on that one.

Now don't all of you johnny come lately's try and step on my toes! I called Dib's!

04-29-08, 09:24 PM
Well I test fitted the SC 3800 this weekend. Here is the 3.0 ready to come out.
Here is the engine bay with the 3.0 removed:
Here is the SC 3800 and 4L60E ready to test fit:
Here it is sitting in place:
With progress, you are presented with problems, as you can see, the stock mounts and perches are in the way:
I will remove them and update as soon as I get a prototype engine bracket.

04-30-08, 09:16 AM
nice man thats awsome keep us posted great work =)

05-01-08, 10:38 PM
one question will you be using the stock differential... and off topic if you swap in a manual transmision on an automatic car will you have to change the differential due to different gear set

05-02-08, 07:08 AM
I'm using the stock diff. The same diff should be fine with a manual. Get the transmission from a 4th generation F body and get the pedal set up and clutch master cylinder off eBay - UK.The firewall already has a place for it.

05-02-08, 08:29 AM
Interesting pictures. What drives the supercharger? Is there a separate belt not shown? Where does the drive come from?

05-02-08, 03:08 PM
I'm using the stock diff. The same diff should be fine with a manual. Get the transmission from a 4th generation F body and get the pedal set up and clutch master cylinder off eBay - UK.The firewall already has a place for it.

thanks for answering my diff question now the thing is the RHD(right hand drive) omegas clutch pedal isnt the same as our lhd ... and they are hard to come by on ebay any ideas where i can find them and will they fit?

05-02-08, 05:55 PM
The Belt wasn't on the Supercharger when I put the motor in. The crank dampner has a second place for the belt and the coil pack mount also has the idler backet built in.

The Clutch pedal set up should be the same but youcould always try the Opel Omega also. I also have gotten parts off eBay Australia - the Holden Commodore is very similar to the Catera.

05-04-08, 10:38 PM
Hey SCcatera97, I have a couple of questions:

Do you have any pictures of the exhaust manifolds you will be using? Are they similar to the 3800 camaro/firebird exhaust manifolds? (headers would be easy to find)

Are you going to move the power steering pump or just get a longer hose? And will the stock Catera hood clear the Alternator? (it would look cool to put a power bulge in the hood)

Also, would the stock oil pan fit in the engine bay? (I know yours will fit, but it looks like it has a lot of room to play with)

05-05-08, 05:39 PM
The Camaro/Firebird 2000-2002 wil not work, the interfere with the steering. I am going to use custom made P/S lines. The Alternator clears the hood just fine.

The stock F body oilpan will not work, ypu will need a front sump pan similsr to the stock Catera 3.0 pan. The Steering and cross member is the problem.

I am in the process of fabricating the motor mounts, I will post pictures as soon as I have them made.

Highline Cady
05-05-08, 06:55 PM
Cool project!!! Good luck getting it finished.

05-28-08, 11:34 AM
SC-catera, I thought you might want to take a look at these threads:



One of them has some heavy engine mods and the other has some stuff for sale....already in the USA!

07-11-08, 11:56 AM

12-05-08, 01:55 AM
anyone know if this guy ever finished this? got some questions for him

12-29-08, 03:34 PM
Alex, You still around here?

I have motor issues and am ready for the swap!

I will give ya a call in a few days if you don't respond.


04-14-09, 11:58 AM
how is the project coming along? any issues that have gotten in the way for the last few months? very interesting project you have going. i see that theres aviable replacement for the cammer motor if it blows a timing belt. keep up the good work.

04-14-09, 06:52 PM
Did this guy vanish? lol

04-14-09, 11:00 PM
Could be that his garage isn't heated so no winter progress on the car. I'm hoping there'll be more news coming on all the engine swaps this summer. I'm stuck with the L81 engine but I live vicariously through these shadetree mechanics.

I think I see a Pontiac G8 in my future but in the meantime my Catera will have to do. I gave in and installed an intake kit in place of the OEM airbox even though I know it does little to improve performance and might even lose some during the hot summer months. Still, the intake howl when I peg the throttle and spin the tach to redline is a rush.

04-20-09, 11:57 AM
Sadly, The OP had to kill off this project just short of the finish line.

I Guess he has a few other projects going that were a little higher up on the food chain. I really wanted to pick up where he left off but I just can't seem to ever get the spare cash to finance it. :thepan:

One Day! one Day.....:bighead:

02-25-12, 09:39 PM
Did anything ever happen with this build?

02-26-12, 04:29 PM
Read the post directly above yours.

Nobody's posted in this thread in almost 3 years, the OP in almost 4.

02-26-12, 06:34 PM
Yes, I thought someone might still have contact with him.

08-25-12, 12:09 PM
ok I,m dropping a small block in my 00 catera its a 350 30 over