3.8L

[spydog]

is the 3.8L V6 in the firebird and camaro the same 3.8L V6 they used in the pontiac bonaville? to me they look the came other than the intake is this true?

[CKJ]

I'm sure they have their differences. Such as the compression, head specs etc. etc. I'm sure Mr. FWD V6 will post up with a whole basket full of knowledge.

[spydog]

ok thanks the reason i am askin is my brother blew up his 3.8L firebird and i have a 1999 pontiac bonaville SSEI that was in a rear end colishion and my brother wants to put my bonnaville engine in his firebird

[CKJ]

wait for a fellow with the s/n of GTP231 to reply, i'm sure he's loaded with bocoup of information on whether it'll work or not

[GTP231]

You'd be better off getting one form a N/A car as the SSEi uses the L67 which is a lower compression engine. The heads are also different from the N/A engines to the supercharged ones as well.
You could use that bottom end but it'll be down on power and have drivability issues from the lower compression than that the tune was designed around

[laux06]

can the sc be used?

[GTP231]

can the sc be used?

TB would be in the firewall so you need to modify it. There's somebody on a V^ site doing it but I haven't heard of much progress in quite sometime. Though I haven't been too active there lately

[laux06]

hmm, i was just curious. seems like it would be a very unique build, plus, why not if hes got the whole motor anyhow.

[GTP231]

hmm, i was just curious. seems like it would be a very unique build, plus, why not if hes got the whole motor anyhow.

There's wiring work as well. Never looked into it so I'm not sure what exactly is involved in that part. I know there's many a Grand Prix GT owner that has done a "top swap"

[2fast4u88]

I've seen all kinds of swaps like this. Top end swaps, computer and harness swaps. Gtp knows more on the boosted 3.8 and probably the rest. Though i can tell you this it will work what is different i'm not to sure about. Gtp i know the blocks are the same. As long as its the same series(even then i know heads switch between some series including the other v6's). I could look this up but is the 3.8 in the f-bodys the same as what he has? What about the pistons? I got from you that the compression would be low. For some reason i think your talking about the boosted 3.8.

Any way i know you have to switch the pulleys. Switch the heads and intake. Along with the flex plate/flywheel. It should run and work but not sure on compression.

Now as for the charger i thought someone already done this some where. I know they have the lt1 procharger kits fabbed upon them. I also know the 3.8 internals out of a grand national has worked in the 3.8 in the f-body.

[spydog]

so if i was to take the block from my bonnaville and take the top end of his engine heads on up it should work?

[laux06]

gtp said the compression would be too low if you use your heads on his block(dished pistons, different cam etc)

[spydog]

darn ok i will look for another block than

[laux06]

you can use the block, just not the pistons/cam/etc

[PoormansVetteWS6]

How about putting a Turbo on the 3.8? to compensate for the lower compression pistons? I mean its an expensive route but think about it - You already have a lower compression motor and all the stuff you basically need (other then the wiring mess you might have lol) for free i guess, so you can then put your money into a cheap budget turbo build? Not running crazy boost or anything. Just an idea though which im sure GTP will not like this idea, which is fine by me dont get me wrong!! :) lol but it would possibly cure the lower compression/driveability issue you will have and maybe give you more power also in the process. (i know it all sounds easier said then done lol)

[2fast4u88]

This is a base model 3.8 right. Not the supercharged one? I don't think the compression would be that low. I'll dig around later spydog. But Poormans idea would be nice.

Edit: you have the supercharged 3800. Now i see what gtp meant. I was thinking it wasn't the l67 for some reason.

Also from what i read the the difference between a regular 3800 and the l67 is the pistons, rods and crank. The L36 and L67 all have the same heads. The exception is the L67 heads had bosses machined for injectors. The L36 had these bosses but they were not machined. And with that being said you would have to switch the top end. And you would have 8.5:1 compression instead of 9.5:1. The car would probably run but don't know what it would run like.

[GTP231]

I've seen all kinds of swaps like this. Top end swaps, computer and harness swaps. Gtp knows more on the boosted 3.8 and probably the rest. Though i can tell you this it will work what is different i'm not to sure about. Gtp i know the blocks are the same. As long as its the same series(even then i know heads switch between some series including the other v6's). I could look this up but is the 3.8 in the f-bodys the same as what he has? What about the pistons? I got from you that the compression would be low. For some reason i think your talking about the boosted 3.8.

Any way i know you have to switch the pulleys. Switch the heads and intake. Along with the flex plate/flywheel. It should run and work but not sure on compression.

Now as for the charger i thought someone already done this some where. I know they have the lt1 procharger kits fabbed upon them. I also know the 3.8 internals out of a grand national has worked in the 3.8 in the f-body.

Intake manifolds and exhaust manifolds are different between the FWDs and the F Body 3800s

[PoormansVetteWS6]

Can you use the intake from the RWD 3.8L on the FWD 3.8L block along with the RWD exhaust manifold to make the engine work in the f-bodies? Or is this swap in general not worth the time and money to attempt? Because i still like the turbo idea i had to compensate for the lower compression pistons in that motor (although the OP may not like the idea and thats totally cool with me i was just throwing a suggestion out there for him), so i just wanted to get your thoughts on this GTP because i like learning new things about odd swaps like this.

[laux06]

well, from my pov, why not just use the stock intake and exhaust off the bird and just use the longblock for boost? no sense in messing with the tb on the back of the intake if you wont be using the sc anyhow right?

[spydog]

I AM GOING TO TRY AND SEE WHAT HAPENS I AM GOING TO USE THE BONNAVILLE BLOCK AND BOLT ON THE FIREBIRD PARTS AND TRY IT IT WONT CAUST ME ANNYTHING BUT TIME TO TRY IT

[2fast4u88]

That is what i meant change the top end gtp. And looking at the manifold after doing that should be a no brainer that the are different.

[GTP231]

Can you use the intake from the RWD 3.8L on the FWD 3.8L block along with the RWD exhaust manifold to make the engine work in the f-bodies? Or is this swap in general not worth the time and money to attempt? Because i still like the turbo idea i had to compensate for the lower compression pistons in that motor (although the OP may not like the idea and thats totally cool with me i was just throwing a suggestion out there for him), so i just wanted to get your thoughts on this GTP because i like learning new things about odd swaps like this.

You'd need the heads off the F Body. There's turboed V6 F Bodies out there already

[PoormansVetteWS6]

Does a turbocharged v6 perform well though? I havent seen a turbocharged v6 fbody in action or in person really i was just killing my own curiousity about this thats all. :)

[Hate Personified]

If you really want to find out how to build up a monster 3800, I suggest looking around the Australian Commodore forums. There the 3800 is referred to as the 'ECOTEC' (Not to be confused with our 4-cyl hunkajunk which shares the name).

They have everything you could want for them, including:
4.2 Stroker kits
3.3L SUPERCHARGER kits (Yes, you can fit a Terminator Cobra Whipple charger on a 3.8!)
Air/Water Chargecoolers that sit between the intake plenum and the Charger
Long tube headers...
the list goes on and on.

I suggest the 'Just Commodores' forum, google it.

[Hate Personified]

Does a turbocharged v6 perform well though? I havent seen a turbocharged v6 fbody in action or in person really i was just killing my own curiousity about this thats all. :)

The Turbochargers ruin the best thing about the 3800, its flat torque curve. Supercharge that mofo.

[PoormansVetteWS6]

Yea that is true i never thought about the flat torque curve of the v6. I dont know much about the V6s thats why im so curious on this subject now lol Well would it be like a budget build to just build the 3.8L with the buick GN internals rather looking into the V6s from australia?

[Hate Personified]

Yea that is true i never thought about the flat torque curve of the v6. I dont know much about the V6s thats why im so curious on this subject now lol Well would it be like a budget build to just build the 3.8L with the buick GN internals rather looking into the V6s from australia?

Definitely not. the GN 3.8 is a GEN I engine, the Series II is a much better motor, not to mention they're highly sought after for real GN rebuilds.
My recommendation would be throw the L67 stuff on the Firebird, and keep the supercharger for now. there's an intake elbow out there to get it to work in an RWD application, they're easily found in australia for cheap, although shipping might be a problem.
The GTP motor, despite the lower compression, is stronger than the Firebird 3800 due to the need for boost.

L36s stock HATE boost.
L67s love it.

Now if you wanted to go and rebuild it N/A, the stroker kit is the way to go.
This is an L36 on stock heads with the stroker, + mild cam, the power increase speaks for itself. (289 BHP / 302 FT.LBS)
http://www.comeracing.com/products/rodscranks/holdenv6/holdenv6_sheet_lg.gif

The most impressive thing to me here is the fact that the Torque is above 270 through the entire rev range until 5750RPM.

[PoormansVetteWS6]

damn thats very impressive numbers! Yea forget the turbo lol hahaha

[Hate Personified]

Now if you got the dished piston package for BOOST, you can slap a Whipple Charger on there and imagine what that can do.

[spydog]

i droped the engine in the firebird last night i got to wire it up tonight and we will see what happens

[Hate Personified]

did you keep the eaton M90 on it?

[spydog]

i just took my bonnaville block and transfered parts from my brothers firbird engine

[Hate Personified]

shoulda kept the gtp parts on it

[spydog]

it wasnt a GTP bonnaville it was a SSEI with a suppercharger

[2fast4u88]

There both the same thing spydog. The superchargered 3.8(aka l67) was in the gtp along with your car.

As for Hate he wanted a drop in deal. Using the charger woudl require more work along with wiring. Different computer also.

He had to shange the heads so he could use the intake for the maro/bird. The l67 heads are different for the injectors. With him using the l67 block with the maro/bird heads. The compression would stay the same. The heads are the same casting one just has the injector holes drilled out.

He can how ever turbo it now which would be way easier. As for the gn 3.8 being old tech. You sure don't know alot. It has been one of the baddest/strongest v6's since made. I have seen 5 different 3800 series two v6 maro's and birds's. Use the gn internals for there strength.

As for using the newer block i don't know why the series one is strong enough. In which i've been around the gn motor since i was little. My uncle has on gn all hopped up and redoing a custom that has the same motor as a gn in it. And the first one has been putting down over 500whp since the early 90's and has been daily driven every year with almost 200,000miles on the motor. And was just rebuilt last summer with new rings, bearings, and gaskets that was it. Cept for a different cam this time.

[PoormansVetteWS6]

Well thats why i was suggesting the turbo route for him. The pipping would be much easier and you can place that turbo pretty much anywhere, either in the engine bay or on the tailpipe for a rear mount option and also not to run crazy boost. I do believe the V6s that are turbocharged are rather quick in my opinion. It was just a suggestion though.

[Hate Personified]

There both the same thing spydog. The superchargered 3.8(aka l67) was in the gtp along with your car.

As for Hate he wanted a drop in deal. Using the charger woudl require more work along with wiring. Different computer also.

He had to shange the heads so he could use the intake for the maro/bird. The l67 heads are different for the injectors. With him using the l67 block with the maro/bird heads. The compression would stay the same. The heads are the same casting one just has the injector holes drilled out.

He can how ever turbo it now which would be way easier. As for the gn 3.8 being old tech. You sure don't know alot. It has been one of the baddest/strongest v6's since made. I have seen 5 different 3800 series two v6 maro's and birds's. Use the gn internals for there strength.

As for using the newer block i don't know why the series one is strong enough. In which i've been around the gn motor since i was little. My uncle has on gn all hopped up and redoing a custom that has the same motor as a gn in it. And the first one has been putting down over 500whp since the early 90's and has been daily driven every year with almost 200,000miles on the motor. And was just rebuilt last summer with new rings, bearings, and gaskets that was it. Cept for a different cam this time.


What I was saying is, if he's using the L67 bottom end, the compression will be lower.
The L67 has dished pistons, the L36 does not.

Also, there are RWD intake elbows made for VY commodores that fit under the hood on a firebird easily.

THEREFORE:
You could have a supercharged 3800, instead of an N/A one with less power.

[2fast4u88]

Yea i know he said he used the l67 bottom end:) He just switched the heads which are the same compression wise.

To run the supercharger on it will probably take piggybacking the l67 computer to the bird one. I'm sure a l67 with the charger will have more plugs for things up top. Which would leave it not running right if ussing the f-body harness and computer.

But with him running it the way he did he could mount a turbo on it later on and get the computer tuned so it sees boost. Like poorman said turbo would he a whole lot easier. Plus a l67 loves a turbo more than the charger and will make some serious power for what it is.


Did you ever get the thing running? I would like to hear back how it went.

[PoormansVetteWS6]

Yea i would like to hear about this too personally.

[spydog]

good news guys the car runs

[PoormansVetteWS6]

Thats good to hear! how did everything go ? and how does the car run?

[2fast4u88]

Yea does it run decent? I doubt the compression drop would be real noticable but who knows. I also wonder if the cams would be different.

[spydog]

i drove it to work yesterday and i put about 80 miles on it and i drove it agen to work today it seams to be running just fine altho idk how it felt to drive before this is my first time driveing a V6 firebird i own a ls1 and i know what that should feel like but it gets up on the hiway fast enough and seams to have plenty of power like my bonnaville did

[PoormansVetteWS6]

Sweet, sounds like you got yourself a good running car now. Although i still wouldnt mind seeing a turbo straped on that engine though ;) just my opinion :lol: jk!!

Hey 2fast, this may sound like a stupid question but lets say the compression drop isnt noticeable but would that effect anything at all? obviously im sure it would hurt horsepower a little bit, but how about the gas mileage? (again it may sound like a stupid question but im just curious myself)

[laux06]

so it has as much power NA as the bonneville did sc'd? whats up with that? is the f body that much lighter? either way, glad to hear its working!

[2fast4u88]

Sweet, sounds like you got yourself a good running car now. Although i still wouldnt mind seeing a turbo straped on that engine though ;) just my opinion :lol: jk!!

Hey 2fast, this may sound like a stupid question but lets say the compression drop isnt noticeable but would that effect anything at all? obviously im sure it would hurt horsepower a little bit, but how about the gas mileage? (again it may sound like a stupid question but im just curious myself)


Um it will affect the power output some. Though i'm not sure if the l67 uses a different cam since it is suppose to be a blown motor. Which might be making up for the difference in compression. But 1pt i think it was you won't notice at all. It might hurt gas mileage only if it's lagging power from before. If so i still say maybe 1 to 2mpg. But the computer might compensate for the drop in compression and allow for some more timing. I'm not to on top of the tune in the v6 birds to know how much is able to be added by the computer.

And laux a stock gtp/ what he has isn't that fast stock. Compared to a v6 bird time wise i'm not sure what they run. But as for weight difference i am pretty sure a lt1 bird weighs like 300lb's more than a gtp. A v6 one will more than likely weigh a little less.

Why i think it might seem faster is the gearing in the tranny and rear. His bonneville in stock form isn't really geared for performance like a f-body. But when mods are added they will run.

[GTP231]

Same cam between the two. But the tune is going to be off from the compression drop. My GTP weighs in the same ball park as F Bodies

[laux06]

cool, i just figured itd feel slower, just seeing how it was boosted, and now its na with lower comp. i agree tho, gearing probably does make a big difference.

[1998silverbird]

Here is a good site to check out about V6 performance..

www.firebirdv6.com (http://www.firebirdv6.com)

I built up my old 98 firebird with a forged 3.8 bored .030 over, with forged internal, pp heads and intakes, and a big ( well back in 2002 it was) Nitrous cam and had a 125 shot on it.. On motor tuned with a Maf Translater plus it put down 230rwhp and 230rwtq.. Stock with bolt ons it made 185rwhp and 210rwtq..

On the spray with the stock tune it made 370rwhp and 433rwtq with a 10.0:1 A/F mixture.. I never had a good pass with the car at the track due to my young age I didnt realize you had to build up the stock Rear and T5.. I broke 4 rears and 2 trannies.. I finally got sick of not being able to drive the car that I sold it and found my 02 WS6 for 15,000 back in 2005.. I put headers, full exhaust, lid, massair, and a Ported TB and bought an extended warrenty for it..

It is easy for the 3.8's to make over 300rwhp.. If I had to do it over again I would have done a turbo.. The stock internals are beefy and the motor is a great motor to mod.. Just a tip.. U can get some L32 stock Forged rods from a 3.8 seris 3 motor for under 200.00 a set.. I used Manley H-Beams that ran about 600.00!!