: informative.......

07-07-10, 07:27 AM

07-07-10, 12:31 PM
Some omissions, though - 2000 saw the change to roller cams, for one.......but still another piece of info to save in the archives.

07-07-10, 01:08 PM
I was just sitting here pondering over this....

I know there have been many revisions to the northstar though it's lifespan, but I was curious if the 2000 heads and ignition could be retro-fitted to the 96-99 generation?

Is there that much difference between the two generations where it's not possible? I have to research this some more..... Any experts have any thoughts on this?

07-07-10, 01:29 PM
Not practical. For starters the crankshaft reluctor wheel for the CKP's (ignition triggers) is totally different. Different head/block oil passages and compression ratios. Different knock sensors and who knows how many other different sensors. Different induction system, from the air filter, through the throttlebody, intake manifold and to the top of the pistons.

07-07-10, 02:00 PM

I definitely understand there are differences. Yet, I just checked the head gasket application for a 98 vs 2000 eldo. the "head' gaskets are the same.

I guess what I really needed to know if it was possible to do a 2000 top end swap and using you existing block and sensors to run the ignition system.

I thick i need to get hold of a 2000 factory service manual.......

07-07-10, 02:38 PM

if you have access to the 2000 "E/K" ignition system wiring diagrams, could you post them? If it's possible could you also post the 98 "E/K" ignition wiring diagram for comparison?


07-07-10, 04:05 PM
I can dig up the 2000+ ignition wiring, but a better bet, if you want the real skinny, would be to subscribe two vehicles - say a 1998 STS and a 2001 STS (or whichever two you want to compare) - to www.alldatadiy.com for a year. Then you can instantly compare any wiring you want. Remember that the ignition, PCM, power, and sensor wiring are all in different circuit diagrams, so it will be sort of fun to suss it all out.........alldata allows you to print diagrams, too.

07-07-10, 04:20 PM

Thanks a million. I found the 2000 wiring diagram and started comparing it to my fsm for my 98.

As we all know there are revisions for the 2000 model year. So far the wiring is similiar but there are differences due to the coil on plug. The camshaft and crankshaft sensors for 2000 are three wires/sensor. While the 98 had two wires/sensor.

I'd have to sit down and figure out what the third wire's function for each sensor. The wiring "looks" more intimidiating than it really is.

I think a 2000 top end swap is quite feasible.......

The question is how easily can it be accomplished....electrically

07-07-10, 08:32 PM
You've seen this, right?:


07-08-10, 01:29 AM

That is where I realized that that if the head gaskets are the same, the head bolts on the the same. I've been studying the differences in the harnesses, I see that the sensors are different. Yet, what I want to see next how much physically different the sensors are and if the pcm's use the same style connectors for data transfer.

"98 - New lower block casting. This new casting incorporates a new threaded hole (M10x1.25) for the new STS platform engine mount. This hole is on the lower right hand side of the engine by the corner of the timing cover. A new timing cover is now used, with a part number stamped in just above the harmonic balancer. Some very late '97 engines may have had this new bolt hole. A new bolt hole is dilled and tapped for the new-for-1998 liquid cooled alternator, just under the cam cover in the L.H. cylinder head.

99 - A very small portion of late '99 model cars got the new upgraded 2000 style block castings. Identified by a casting # in the R.H. oil passage in the block that feeds oil to the R.H cylinder head. This engine retained all internal components and cylinder heads from '98. 10.3:1 compression ratio has been retained ever since its introduction in 1993.

00 - A new engine is born. All new cylinder heads featuring static hydraulic lash-adjusters and roller followers are used. These heads feature a new combustion chamber with less valve shrouding and larger intake valves. Exhaust valves are a bit smaller, both intake and exhaust valves have longer stems. New camshaft covers are used to accomodate the increased height of the roller valvetrain. A new crankshaft with a different reluctor wheel (crank position wheel) is used, but all bearing journals retain the same dimensions. The bore remains at 93mm as its predecessors. Cast connecting rods are used as opposed to the forged ones of 93-99, and are weaker. These have been known to bend if a cylinder hydraulic locks with coolant or fuel. New completely flat-top pistons with no valve reliefs are used along with a different diameter wrist pin. The timing cover, oil pan, and flex-plate all remain the same from '99. The timing cover uses a new crankshaft front seal with an increased inside diameter. A new harmonic balancer is used and also a new right exhaust cam sprocket to accomodate the new camshfaft position sensor. The knock sensor retained the same location as the 96-99's but a new sensor is used for '00. New crankshaft position sensors are used and will not interchange with the old style. There are new EGR passages incorporated into the exhaust ports. A new coil-on-plug igniton system is used that uses two large coil cassettes that houses the four coils and ICM. These cassettes bolt into the camshaft covers and use a center-mounted spring to ground themselves to the cylinder head. A new coolant crossover has been designed with a throttle body mount cast into it. A new plastic intake is used along with a new plastic & stainless steel fuel rail and new Bosch fuel injectors. AC-Delco spark plug 41-987 is used now instead of the 41-950 from '99. The camshafts no longer are drilled through for oil flow- the oil flow to the cam journals now comes from an oil passage that runs parallel along the head. Also longer head bolts are used. The new 10.0:1 compression ratio allows for full performance on 87 octane fuel. "

According to this useful information, in 98 the lower block casting was changed to accomdate the STS platform .

In late 99, some of the blocks were actually 2000 by the casting # in the right side head oil passage, that feeds oil to the head. "This engine retained all internal components and cylinder heads from '98. 10.3:1 compression ratio has been retained ever since its introduction in 1993."

Therefore just from this statement alone, if the early 00's blocks had 99 heads on them, and the head gaskets are the same "physically" the 00 upper system should bolt on to an earlier block.

The main revisions here are mostly to the cylinder heads. Of course with the C.O.P setup the triggering of the system is different than the earlier version therefore the sensor changes and crankshaft postion wheel change.

If it could be done, you could use the 93-99 forged rods and rotating assembly or just the 96-99 era blocks. Incorporate the 2000 heads with the better valvetrain. Use the 00 intake, ignition and revised coolant cross-over pipe. You would have a better valvetrain and stronger rotating assembly, and possibly lower compression ratio (that would have to be calculated), run on possible 87 octane and the best of the northstar parts offerings. Of course, I'd stud the block before assembly. (My personal preference).

I think in the end it's going to come down to a pcm and wire harness/ sensor adaptation or just a wire hareness/ sensor adaptation.

I will continue to compare......

07-09-10, 11:42 PM
I've been dreaming of this for a while.

93-99 have stronger bottom ends than the '00+. 00+ have better heads (in some ways).

The kicker is the intake manifold bolt pattern and port differences and also the camshaft position sensor. You would use the '98 crank, '98 block, 98 crank position sensors. The knock sensor would be retained from the '98 block, no issues there. You would have to re-work the coolant crossover or use the new style intake manifold. Then you run into issues with injectors and such.

It's simply not worth doing. It could be done. Just too much to mess with.

07-10-10, 01:09 AM
You may be right... somehow I feel that it can be done.

I know these motors are different yet the general made modifications to the 60 degree v6. I heard that a top end swap was feasible on that motor, I had to investigate it.

Ironically in 2000 they had switched injector styles to a thinner style injector. The "newer" big port intakes on the 3100/3400 engines yield better power and performance with the 2000+ heads. It wasn't a straight bolt on swap, but damn close.

Even with the "new" style injectors, the fuel pressure was still the same at idle. I could have adapted the "new" style injector harness to my 96 grand am gt, but I felt if the fuel pressure is still the same at idle why use the new style injectors when mine are working great doing the same thing.

The car runs great to this day. 96 grand am gt with a 2000 malibu upper and lower intake, throttle body and with 2000 malibu heads?!

The general rarely makes changes to where the previous generation can't benefit from it's revisions....

I hope they haven't changed their ways......

07-10-10, 11:31 AM
Don't confuse "model year" with "calendar year". 2000 Seville, and all its parts, began to be assembled in July of 1999, so it's entirely possible that an engine block labeled "2000" was actually cast/machined in May of 1999, and then 2000 changed to "2001" parts production in May of 2000.

There's a 7-month glitch in parts dating. On many parts you can find several "clocks" - a year dial from maybe 99 - 04, a month dial from 1 - 12, a day dial from 1 - 31, and a shift dial from I - III. Deciphering the "times" on the dials gives the year, month, day, and shift in which the part was built.

07-11-10, 02:20 AM
Sir, you are definitely correct about that. I should thought about that..... Thanks