So i just finished rear mount turbo'ing my 04 cavalier and what should happen to fall in my lap? A olds aurora with a 4.0 northstar.. Ok so it is time to do the swap i have been pondering for years. I have no issue with any of the swap but i am curious if anyone knows anything about the heads. Will i get bigger valves cams or ports with heads of a cadillac northstar? I would think being of bigger displacement it would have to have something. If anyone can help it would be appreciated.


Remember... One test is worth a thousand expert opinions.

Remember... One test is worth a thousand expert opinions.

its already been done by a guy from canada.

Never said i wanted to be the first, Just figured i would share what i was getting ready to do.


Remember... One test is worth a thousand expert opinions.

Lol I'd just drive the Aurora as is.

Why would you ruin a Cavalier by putting a sh itty Northstar in it?



Hahn Stage II - Mitsu TD06-20g |3" Turbo-back Exhaust | 61mm Bored TB |
HP Tuners | Innovate WB02 | Spec Stage 3 | Team Green LSD | TurboTech Upper | Full Addco Sways | Sportlines & Yellows |

I have to remove the engine to fix the headgasket anyways and its a boat.. How can you consider the northstar @!#$ty? It was designed as the lt5 for the early 90's corvette zr1's and cadillac picked it up made it smaller and said.. Enjoy! There are many reasons to consider doing this why dis-agree with me just because you dont have the means or desire to do it? aurora 4.0 250 hp @6500 and 260 lb ft @ 4400 and the Ecotec 140hp and 150 lb ft. Dont get me wrong i have enjoyed the eco but it just dosent have to potential that i want without going crazy with rpm or boost. Besides i plan on re-doing my rear mount setup to work with the northstar which should be freakin awesome. and last but not least 4t80e


Remember... One test is worth a thousand expert opinions.

Do it man, would be a fun car.


- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs

Have fun with all that torque in such a light car. Once you get it in and running, you'll find out why everyone suggests having the ECOTEC. Trust me on this, the torque WILL get to be a burden.





i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick

hell u can deal with the torque.. just gotta know how to feel a V8.. do it!!



sr71blackcav

I didnt know 300 ft lbs out of a v8 was different than 300 ft lbs out of a eco. And im pretty sure im not going to have some 195 wide tires on it....


Remember... One test is worth a thousand expert opinions.

why stop there just put a 35 ton CAt motor in there.

dude save yourself the time and leave the motor where it is the north star is a POS. mechanics call it @!#$star the power you get our of a northstar can be had out of a 3800SC plus some just cause you get it cheap doesn't mean its worth doin guys get series 1 SC all the time but 3400 make as much power as them. just cause its cheap doesn't make it right



JBO since July 30, 2001

hey nota24 do you have any vid of you driving your 3800? i wanna see what that thing is capable of

i might have to check but they wont be posted in this thread as i wont jack someones thread



JBO since July 30, 2001

Have fun when the starter goes out and you have to pull the motor so you can get the intake manifold off to change the starter...

Why would they put the starter under the intake? GM engineers do some very stupid stuff.

"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"

northstars are notorious for blowing headgaskets. my 99 eldorado blew at 80,000 miles. at 50,000 miles it would burn a qaurt every 500 miles. and it was a very well maintained car. my turbo ecotec would eat the hell out of the eldorado and gets 8 more mpg!! plus if i remember right my friend has messed with a couple and you need alot of special tools to even work on them


running rich? turn the boost up

Josh A wrote:I didnt know 300 ft lbs out of a v8 was different than 300 ft lbs out of a eco. And im pretty sure im not going to have some 195 wide tires on it....

Its all in the power curve. 300ft/lbs at a higher RPM (which is what the Eco would do. And pretty much all smaller engines for that matter.) will be more manageable since you wont be lighting up the tires or fighting torque steer at low RPMs. V8s make more torque low. So taking off with any grace or speed will be fun.

thats why a saab turbo eco will run time close to my car but i have 300ish ftlbs of torque and they have say 220ish

mine is early and i have to feather the throttle but they can just giver



JBO since July 30, 2001

sr71blackcav wrote:hell u can deal with the torque.. just gotta know how to feel a V8.. do it!!

You must be an idiot.

You're pretty limited on what you can do with that torque on a FWD car. I had nothing to do with any "FEEL" of a V8. In a FWD car upon acceleration you still get a weight transfer to the rear wheels. The extra torque just turns into smoke. Trust me, I'm putting a fair amount over 200 ft/lbs and it doesn't to a damn bit of good once the wheels start to lose the weight on them. The only thing it does seem to come in handy for is top gear acceleration, or the fact that I can climb up hills without having to downshift better than one of those little VW things with the turbodiesel.





i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick

SHOoff wrote:

sr71blackcav wrote:hell u can deal with the torque.. just gotta know how to feel a V8.. do it!!

You must be an idiot.

You're pretty limited on what you can do with that torque on a FWD car. I had nothing to do with any "FEEL" of a V8. In a FWD car upon acceleration you still get a weight transfer to the rear wheels. The extra torque just turns into smoke. Trust me, I'm putting a fair amount over 200 ft/lbs and it doesn't to a damn bit of good once the wheels start to lose the weight on them. The only thing it does seem to come in handy for is top gear acceleration, or the fact that I can climb up hills without having to downshift better than one of those little VW things with the turbodiesel.

x 2

errrrr euck euck v8 280 ftlb @ 3000 rpm no traction/topend kodjiak l derrrrrr you dont know nutthin euck'



Hahn Stage II - Mitsu TD06-20g |3" Turbo-back Exhaust | 61mm Bored TB |
HP Tuners | Innovate WB02 | Spec Stage 3 | Team Green LSD | TurboTech Upper | Full Addco Sways | Sportlines & Yellows |

For the difficulty working on it i deal with them all the time, Im a ase master tech and i have been doing this for a while. Yea you can get the same power out of a 3800 sc but you dont get the smoothness of a v8, and im pretty sure turbo 4.0 is greater than super charged 3.8. It has only come to me cheap because i have been looking for one for the last couple years and have had the patients to stick with it.


Remember... One test is worth a thousand expert opinions.

Im sorry i dont want to sound like a know it all. But i think northstars have gotten a bad rap for no reason. Sure at 150 thousand miles they blow head gaskets. Just a good excuse to put head studs in. yes gm mounted the starter under the intake. It never gets exposed to exhaust heat and basically never fails. I really like the northstar and think after you take care of its headgasket weakness they are basically bullet proof.


Remember... One test is worth a thousand expert opinions.

Ive spent A LOT of time in L67 powered cars. Im not sure what you mean by the powerband isnt smooth. They pull hard and smooth from idle. Sure you have to roll into the throttle a little to keep the tires from spinning but youre going to have to do that with a Northstar.

I have nothing against 3.8's im very impressed with all the swaps i have seen. I just want a 4.0 northstar.


Remember... One test is worth a thousand expert opinions.