: What were the revisions to the Northstar in 2000?



I~LUV~Caddys8792
02-28-07, 10:08 AM
I've heard on here that the Northstar was reworked a bit in 2000, making a more fuel efficent and reliable engine, and IIRC, the post 2000 Northstars have a lot less problems with headgaskets. What were all those changes?

JimD
02-28-07, 02:05 PM
Roller cam followers.
Redesigned combustion chamber and a point or so lower compression ratio.
Thread pitch changed on head bolts and slightly longer threaded section.
COP ignition.
PCV arrangement changed.
Seconday AIR pump.

That's all I can remember.

caddydaddy
02-28-07, 06:53 PM
Compression dropped from 10.3:1 to 10:1. And what he said! :)

Cadillacboy
02-28-07, 07:05 PM
I also wonder why 2000 and up has a silencer engine ? I don't think resonator itself would do that considering some owners took it off but no difference

CadillacSTS42005
02-28-07, 07:48 PM
most likely people complained it was too loud
remember we do drive "old ppl cars"
we just drivem like we stolem ahahaha :burn:

I~LUV~Caddys8792
02-28-07, 07:53 PM
So basically, they were easier to do maintenance on, the HG wasn't as much of an issue, they were more reliable and they ran 87 octane?

The reason I ask is I've always been a little leery of the Northstar's reliability and durability, but I love the 96-02 Eldorados...it's the #1 car I wanna buy next, but my parents are anti-Northstar, but if I found a ETC, in the right colors, with the right options, with low mileage and records of the maintenance, I'd try and convince them so we can all win.

Cadillacboy
03-01-07, 11:28 AM
most likely people complained it was too loud
remember we do drive "old ppl cars"
we just drivem like we stolem ahahaha :burn:
Yeah I forgot that olds ppl cars thingy lol .I can't think how much HP a Northstar would hit if it was a youngster car considering old ppl has 300 HP lol


So basically, they were easier to do maintenance on, the HG wasn't as much of an issue, they were more reliable and they ran 87 octane?

The reason I ask is I've always been a little leery of the Northstar's reliability and durability

Chad, you can run 87 octane in newer Northstar but from what ppl say , the higher octane you run the more mileage you get .
I have been using premium in my cars but I see let's say if you own a fleet then a few cents per galon would be matter considering annual mileage

BodybyFisher
03-01-07, 01:58 PM
So I need to ask a question about the 2000 Northstar. I am considering buying a 1998 to 2000 STS in the spring. Is it my imagination or have I noticed that the 2000 NS seems to need pistons/rings more often due to uncontrollable oil burning and the inability to clean them once they become caked up? I understand that if this year was 'babied' its not good...

If this does in fact occur, what component is related to the 2000 that could cause this?

My gut is, I want a 2000, but if the 2000 has a propensity to have that problem.... I might avoid it. What do you guys think

Ranger
03-01-07, 06:11 PM
My daughters '02 SLS (Ruby) and my '03 DHS, both burn much less oil than my '97 did.

caddydaddy
03-01-07, 08:40 PM
I run my 2000 STS hard, and it doesn't use much oil.

99Classillac
03-05-07, 11:14 PM
My 99 uses up a good bit of oil. I burn up to 2 quarts before I even get to an oil change, and I run it like its a damn civic at a street race, except it's not a civic. It's way more than that. It's an elegant lady called my Classillac.

Aurora40
03-06-07, 12:12 PM
There is a big section in the middle describing the engine changes:

http://media.gm.com/division/cadillac/products/00cadillac/seville/00press.html

I seem to recall there being a Powertrain release too, though it's a bigger pain to search for those.

AlBundy
03-06-07, 12:48 PM
Thanks for sharing. Info I wanted to know as well.

jadcock
03-06-07, 05:51 PM
I think that "center feed" intake manifold is the reason for the quieter operation (especially for the lack of "intake growl" at WOT).

Does anyone know where the electric air pumps are, if the car has them? That link (excellent link Aurora40) mentions electric air pumps if the car is a LEV vehicle. The RPO codes on my 2001 STS indicate that it has the federal emission system certification (no special CA or NY or anything like that), but also that it carries the NLEV certification (National Low Emission Vehicle). I haven't seen where the air pumps are.

Thanks.

BodybyFisher
03-06-07, 06:02 PM
I think that "center feed" intake manifold is the reason for the quieter operation (especially for the lack of "intake growl" at WOT).

Does anyone know where the electric air pumps are, if the car has them? That link (excellent link Aurora40) mentions electric air pumps if the car is a LEV vehicle. The RPO codes on my 2001 STS indicate that it has the federal emission system certification (no special CA or NY or anything like that), but also that it carries the NLEV certification (National Low Emission Vehicle). I haven't seen where the air pumps are.

Thanks.

Jason, this is from 2001 and #2 is a photo of the air pump, Mike

JimD
03-06-07, 07:00 PM
Another item I noticed on the '04 engine is the cooling system purge line does not go through the throttle body. Maybe that change occured in 2000?

jadcock
03-06-07, 09:26 PM
Thanks Mike. That appears to be up in the front corner, under the airbox.

ted tcb
03-07-07, 10:24 AM
Here's another link to the 4.6l motor.

I'm confused. They suggest that some cars came with a water cooled alternator, and this was changed in 2001 to an air cooled design, to eliminate the chance of potential leak points.

Anyone know which year Northstars have water cooled alternators?

ted tcb
03-07-07, 10:40 AM
Here is the link.

http://www.aa1car.com/library/2002/us100232.htm

CraniumShot
03-07-07, 04:26 PM
So I need to ask a question about the 2000 Northstar. I am considering buying a 1998 to 2000 STS in the spring. Is it my imagination or have I noticed that the 2000 NS seems to need pistons/rings more often due to uncontrollable oil burning and the inability to clean them once they become caked up? I understand that if this year was 'babied' its not good...

If this does in fact occur, what component is related to the 2000 that could cause this?

My gut is, I want a 2000, but if the 2000 has a propensity to have that problem.... I might avoid it. What do you guys think

You know about the Main Seal problem and how much it will cost you, right?

BodybyFisher
03-07-07, 05:33 PM
You know about the Main Seal problem and how much it will cost you, right?

Is this specific to the 2000, or all NS's?

Ranger
03-09-07, 10:21 AM
Here's another link to the 4.6l motor.

I'm confused. They suggest that some cars came with a water cooled alternator, and this was changed in 2001 to an air cooled design, to eliminate the chance of potential leak points.

Anyone know which year Northstars have water cooled alternators?

Ted,
I think it was started in '98 or '99. The link says they stopped in '01. The water cooled alternators only had a 2 or 3 year life span.

caddydaddy
03-09-07, 10:26 AM
The water cooled alternators only had a 2 or 3 year life span.

Hmm...that's interesting! The water cooled alternator in my 2000 STS is now over 7 years old with almost 90k miles.

caddydaddy
03-09-07, 10:28 AM
Another item I noticed on the '04 engine is the cooling system purge line does not go through the throttle body. Maybe that change occured in 2000?

My 2000 has the coolant lines go through the TB.

ted tcb
03-11-07, 12:27 AM
Hmm...that's interesting! The water cooled alternator in my 2000 STS is now over 7 years old with almost 90k miles.


I think Ranger meant the water cooled alt was only in production for 2-3 yrs.

Ranger
03-11-07, 05:02 PM
Thanks for the correction Ted. After rereading that, I probably should have said a 2 - 3 year production run. I did not mean to imply that they are unreliable.

caddydaddy
03-11-07, 07:25 PM
Thanks for the correction Ted. After rereading that, I probably should have said a 2 - 3 year production run. I did not mean to imply that they are unreliable.

Sorry! I am easily confused! :alchi:

Hopefully if my water cooled alternator ever fails, the limited production won't pose a problem of finding a replacement.

Ranger
03-11-07, 10:38 PM
The list of new Northstar V8 features includes:

*

Roller-follower valvetrain design
*

Improved combustion chamber configuration
*

Center-feed intake manifold
*

New pistons
*

Coil-on-plug cassette ignition system
*

Siemens powertrain control module (engine/transmission control computer)
*

Exhaust manifolds with integral air-injection passages
*

Flex pipe between the exhaust Y-pipe and the catalytic converter
*

Twin electrically driven, two-stage air pumps (LEV applications only)
*

Direct mounting of all engine-driven accessories (power steering pump, AC compressor, electrical generator)
*

Integrated coolant crossover and throttle-body support

The Northstar’s fuel recommendation changes from premium (93 octane, lead-free) to regular, resulting in a major reduction in operating expense. To facilitate this gain, the Northstar’s compression ratio was lowered from 10.3:1 to 10.0:1.

One result of these improvements is that the 2000 Seville will be certified for sale in California and certain Northeast states as a low emissions vehicle (LEV). This was achieved by means of a reaction-heated catalyst, pistons with reduced crevice volume and a new combustion chamber design.

Engine Design Changes
Revised combustion chambers are superior to previous designs in terms of both tumble motion of the incoming fuel-air mixture and burn rate. The intake and exhaust valves have been resized. Larger intake valves improve the engine’s breathing ability, while smaller exhaust valves increase flow velocity, an aid to catalyst light off.

While the new combustion chamber design helps maximize fuel efficiency, even larger gains are made by the addition of roller-follower devices between each cam lobe and valve stem. Compared to the previous Northstar’s direct valve actuation, the result is a substantial reduction in friction. During moderate driving conditions, the torque necessary to turn Northstar’s four camshafts is reduced by 50 percent or more.

The Northstar also benefits from a new ignition system that delivers power to the spark plugs directly instead of through wiring. A cassette containing four ignition coils linked by short secondary leads to adjoining spark plugs now attaches atop each cylinder head cover.

In addition to improved reliability, the new ignition system permits scheduling the magnitude of the voltage sent to the spark plugs. High voltage is used during full-load, high rpm and heavy EGR (exhaust gas recirculation) conditions to guarantee complete combustion. The energy level is reduced to minimize electrical loads and radio frequency interference during light-load conditions, such as medium speed cruising. The result is extended spark-plug life and a peak energy capacity that is 130 percent higher than the system it replaced.

Northstar’s new powertrain control module is a single circuit board device housed within a sealed aluminum case engineered to withstand the harsh underhood environment. The module contains dual microprocessors to monitor and direct engine and transmission operations.

Noise and vibration improvements are the result of adopting a center-feed design for the composite-plastic intake manifold, as opposed to the previous end-feed design. The new design facilitates a near equal-length induction path for all eight cylinders. In contrast, the previous design provided a long path to the front cylinders and shorter paths to rearward cylinders. With the reduction or elimination of many harmonic tones, the resulting induction sound is more of a hum.

A molded-plastic cover backed with acoustical foam rests above the intake manifold to reduce induction, fuel-injector and other noises radiated by the engine. Direct mounting of accessories eliminates flex and vibration inherent with extra brackets. A flexible connection in the exhaust system en route to the catalyst helps quell another source of noise and harshness.

jadcock
03-12-07, 06:44 AM
I understand the 2000+ engines also saw a head bolt pitch/length change, but no GM documentation seems to support that.


Noise and vibration improvements are the result of adopting a center-feed design for the composite-plastic intake manifold, as opposed to the previous end-feed design. The new design facilitates a near equal-length induction path for all eight cylinders. In contrast, the previous design provided a long path to the front cylinders and shorter paths to rearward cylinders. With the reduction or elimination of many harmonic tones, the resulting induction sound is more of a hum.

Personally, I prefer the "many harmonic tones" of the old system. :)

JimD
03-12-07, 08:51 AM
I understand the 2000+ engines also saw a head bolt pitch/length change, but no GM documentation seems to support that.The service manual Engine Mechanical specifications are clear regarding the depth and pitch of the holes for the 10 bolts that provide the head gasket clamping force.

From 1998 manual; all ten holes are 70mm deep. Thread depth is not noted and the bolt is M11 x 1.5.

From 2004 manual; the five holes on the intake side are 73mm deep and the five holes on exhaust side are 89mm deep. Minimum thread depth is given as 67mm and 83.5mm respectively. Bolts are M11 x 2.0.

jadcock
03-12-07, 08:55 AM
Thanks Jim. I'm glad to know that.

JimD
03-12-07, 08:57 AM
Plus there is one TimeSert kit part # for the '95-'99 engine and a different TimeSert kit part # for the 2000+ engine.

Cadillacboy
03-12-07, 12:17 PM
Ranger thanks for posting in details .
PS-I like the harmonic tones too !

TexasCadillac
06-18-07, 01:52 AM
Did I read that northstar engines can not be bored? And oversize crank bearings not available. If so it's not a rebuildable engine to me. Wow if this is so I may sell my Deville and find a 93-96 Fleetwood with a 350 V8. The more I learn about N the less I like it because I know my car is a throw away car with the N engine. And how much does a water cooled alternator cost? I am sitting down to read the answer. LOL O well it's running fine now. TexasCadillac

jadcock
06-18-07, 07:56 AM
Why do you think you need to bore an engine to rebuild it? Why do you even think you need to "rebuild" it? If it needs new head gaskets, just put on new head gaskets. If you would rather have an old-school 350 engine just so you can apply old-school backyard mechanic practices, that may be the way to go. Not to be terse, but old-school repair procedures don't apply to the Northstar engine (and many "new" engines in fact). The bottom end is nearly bulletproof (meaning you'll never NEED a ground crank with oversize bearings). The cylinder walls have a very aggressive hatch pattern from the factory, making the NEED to bore the cylinders a thing of the past. If you have the opportunity to open up a high-mile Northstar engine, you'll appreciate these design elements that went into it at the factory.

I'm opposite of you -- the more I've learned about this engine, the more I respect it and enjoy driving it.

Ranger
06-18-07, 10:38 AM
Jadcock is correct Tex. our old Guru has told us many times that they tore down 250K engines and there was not even a ridge to be cut at the top and that the factory hone pattern was still visible. About the only thing that ever has to be done is Timeserts and head gaskets.

srx2005
12-13-07, 08:11 PM
2000 ETC 51K miles. Burns about a quart of oil every 1500 - 2000 miles.

tateos
12-13-07, 08:25 PM
2000 ETC 51K miles. Burns about a quart of oil every 1500 - 2000 miles.

That's normal for a Northstar

dwight.j.carter
12-13-07, 09:27 PM
So I need to ask a question about the 2000 Northstar. I am considering buying a 1998 to 2000 STS in the spring. Is it my imagination or have I noticed that the 2000 NS seems to need pistons/rings more often due to uncontrollable oil burning and the inability to clean them once they become caked up? I understand that if this year was 'babied' its not good...

If this does in fact occur, what component is related to the 2000 that could cause this?

My gut is, I want a 2000, but if the 2000 has a propensity to have that problem.... I might avoid it. What do you guys think

I'm sure I will get burned for opening this can of worms. But on my 2000 it was run it's whole life on synthetic with no oil burning and this last oil change I did I put in Valvoline Max Life and it has burned some oil. Needless to say I am switching to Mobil 1 and I recomend if you have a 2000 or newer you do the same. The CTS VVT calls for it and I would think if it has thinner oil via synthetic it would burn less because there would be less buildup on the rings.

Submariner409
12-13-07, 10:08 PM
Yep, the oil threads come and go, and 1 N* in 10,000 burns some oil. My '02 runs on Pennzoil 5W-30 Platinum synthetic and uses 1 quart every 3,500 miles.

To put it all in perspective, AJ or eWill3, how many N* engines are on the road ????

JimD
12-13-07, 10:11 PM
I'm sure I will get burned for opening this can of worms.Here comes the fire-starter.

But on my 2000 it was run it's whole life on synthetic with no oil burning and this last oil change I did I put in Valvoline Max Life and it has burned some oil.How much is "some oil"? Put a pencil to the $$$ difference between oil changes!

....The CTS VVT calls for it and I would think if it has thinner oil via synthetic it would burn less because there would be less buildup on the rings.Buildup of what on the rings? Carbon? There is a well documented procedure to remedy carbon buildup on Northstar piston rings. The procedure is effective, inexpensive, and fun.

And how do you make the leap from oil recommendation for a ("old design") V8 Northstar to oil recommendation for a "modern" VVT V6?

How does this convoluted logic survive the current digital information age?

[SOAPBOX MODE = OFF]

clarkz71
12-16-07, 09:25 AM
Yep, the oil threads come and go, and 1 N* in 10,000 burns some oil. My '02 runs on Pennzoil 5W-30 Platinum synthetic and uses 1 quart every 3,500 miles.


Same here, my 95 Eldo only "uses" a 1/2 qt in 4000 miles.

dwight.j.carter
12-18-07, 09:09 PM
Here comes the fire-starter.
How much is "some oil"? Put a pencil to the $$$ difference between oil changes!
Buildup of what on the rings? Carbon? There is a well documented procedure to remedy carbon buildup on Northstar piston rings. The procedure is effective, inexpensive, and fun.

And how do you make the leap from oil recommendation for a ("old design") V8 Northstar to oil recommendation for a "modern" VVT V6?

How does this convoluted logic survive the current digital information age?

[SOAPBOX MODE = OFF]

what I mean is by using synthetic they get less caked. The VVT is very simillar to the newer RWD Northstar minus a couple cylinders. I would think they use a simillar ring setup because my brother's burns some oil now and again. Mine only starts to burn when the oil gets dirty. So with that being said if you are burning some oil perhaps you should change your oil more often. I go by the sensor for the most part but I also visually inspect my oil condition and if it looks dirty I change it. Mine is looking dirty now as a matter of fact and the sensor is only to 50% but mine is getting changed this weekend. And I am using Mobil 1 from now on.

Ranger
12-18-07, 09:18 PM
Dirty oil does not cause the engine to burn more oil.

Just because the oil "looks" dirty is no reason to change it. It will look dirty again shortly after a change. That is what it is supposed to do.

Submariner409
12-18-07, 11:05 PM
Damn good thing most people in here never look at the oil in a big Kenworth or Peterbilt after 500 miles............or a Cummins twin turbo V-12 575hp workboat engine. 15W-40 tar.

Good lube oil is supposed to "look" dirty, otherwise the nasties are caked onto your engine guts. "Detergent" oil, remember ???

........and as far as consumption goes, it makes not one whit of difference if the engine is VVT, OHC, DOHC, OHV, flathead, F-head, rotary, V, flat, whatever......consumption is tied to mechanical fit and finish, maybe a little to cold weather oil dilution by gasoline, perhaps a bit more due to age/mileage, and of course to the abuse the engine gets (abuse, not hard use). One engine off the assembly line may use a quart every 1,000-1,500 miles, and the very next one will go 4,000.