Northstar differences

[scottydl]

I should probably know this, but....

Are there any differences in the 4.0L Northstars in our two styles of Auroras (95-99 vs. 01-03)? Or is it the same exact engine?

And how does our Northstar differ from those in the Cadillacs and new Bonneville GXP's? I know there are 4.6L and our 4.0L's, but that's about as far as my Northstar knowledge extends.

[erw38]

The engine, I believe, is essentially the same (the 4L that is) between all the auroras. There have been some minor changes, but for the most part I believe that are unchanged. The caddys (which use the 4.6) are basically the same engine with the cylinders bored out a little more. That translates in more HP but also more gas used.

Feel free to tell me I am wrong on this one as this info is only an educated guess.

[Aurora40]

scottydl said:

I should probably know this, but....

Are there any differences in the 4.0L Northstars in our two styles of Auroras (95-99 vs. 01-03)? Or is it the same exact engine?

And how does our Northstar differ from those in the Cadillacs and new Bonneville GXP's? I know there are 4.6L and our 4.0L's, but that's about as far as my Northstar knowledge extends.

The difference between 1999 and 2001 4.0's is significant, as is the difference between 1999 and 2000 Northstars. The GXP is basically the same as the 2003 Northstar, as it is a Northstar itself.

Look around here, the 1999 to 2001 4.0 difference has been mentioned in great detail.

Edit: This is all I could find, but I thought I posted the drivetrain press kit: aurorah.proboards20.com/index.cgi?board=Lounge&action=display&thread=1089931677

Marc also posted something, but I can't find that either. Man does the search here suck. It never returns any results at all...

[Marc]

The differences between the 1995/99 and the 2001/03
4.0 are as follows:

1. Camshaft: The 2001+ has rocker arms for more valve
lift. Duration is the same for both engines.
2. Valves: the 2001+ has larger intake valves.
3. Intake & exhaust ports: larger on the 2001+.
4. Intake manifold: higher flow rate on the 2001+.
This is the same intake manifold from the 4.0 HO
that the Shelby Series I has.
5. The 2001+ uses roller lifters & rocker arms.
6. Coil on plug ignition in the 2001+. This eliminates
spark plug wires.

_______________

GM!!! BRING BACK OLDS!!!

[scottydl]

Thanks all, great info and the differences really aren't as major as I thought.

Thanks for the Press Kit link Aurora40, that was a good read and I hadn't run across it yet. Although the article mentioned that 45,000+ Auroras were being manufactured annually beginning in 2001? Didn't it end up being *much* smaller numbers?

[Aurora40]

scottydl said:

Thanks all, great info and the differences really aren't as major as I thought.

Thanks for the Press Kit link Aurora40, that was a good read and I hadn't run across it yet. Although the article mentioned that 45,000+ Auroras were being manufactured annually beginning in 2001? Didn't it end up being *much* smaller numbers?

There were something like 55,000 2001 Auroras built. However, I'd bet more than 2/3rds were 3.5's and many were built for fleet/rental use. Also, the 2001 model year was about 1.5 model years long. Before the 2002 model year, the division was canned. I think about 10,000 2002's were sold, with under 3,000 being 4.0's. It makes me wonder if there are more Final 500's out there with Dark Cherry Metallic than there are 2002 4.0's with Cherry Metallic...

Edit: Here's the thread that has the numbers courtesy of Marc: aurorah.proboards20.com/index.cgi?board=nextgeneration&action=display&thread=1088783029

And here is the other press kit I posted (though I thought I'd posted more of them): aurorah.proboards20.com/index.cgi?board=Lounge&action=display&thread=1090201636

[SupaStealth]

hmm, so since the intake manifolds are bigger on the 2001's, are the port locations the same as in the classic aurora's? that would be a nice upgrade.

[JimW]

Man, we are so on the same page....hrm...would be nice, I hope its all bolt on work

[SupaStealth]

JimW said:

Man, we are so on the same page....hrm...would be nice, I hope its all bolt on work

lol, yeah, that would be nice, i might have to look around at some junk yards for some newer 4.0 Auroras ;D, hmm, i wonder if the throttle body is bigger too...

[Aurora40]

SupaStealth said:

lol, yeah, that would be nice, i might have to look around at some junk yards for some newer 4.0 Auroras ;D, hmm, i wonder if the throttle body is bigger too...

The throttle body is completely different. And the heads had different sized ports. I think it would be difficult to get the intake to match up right to the heads and to mount the TB to it, but you can always give it a try, especially if you find a junk one cheap. Apparently about 80% of the parts were new in the 2000+ engine, so they are not all that similar except in basic architecture.

[R4D30N]

actually, the motor should bolt right up, according to people that do to oilpan gasket alot :\

[SupaStealth]

well actually, i'm not talking about bolting a new 4.0 in my car, according to my post 2 or 3 up, if the intake manifold 'n stuff would bolt up since they are bigger supposedly.