: northstar head switching



RATZLAFF
04-25-06, 08:27 PM
Will 2002 northstar cylinder heads interchange or swap into 1998 northstar engine? all parts are vin 9 but I notice the 2002 heads have a long slot over the exhaust ports? does anyone know if the 1998 exhaust manifolds will work with the 2002 heads etc. thank you, Mark

Ranger
04-25-06, 09:01 PM
2000+ has COP (Coil On Plug) so I am guessing that there are differences that would disallow it, but I may be wrong. See what others have to say. No idea on the exhaust manifolds.

RATZLAFF
04-25-06, 10:23 PM
2000+ has COP (Coil On Plug) so I am guessing that there are differences that would disallow it, but I may be wrong. See what others have to say. No idea on the exhaust manifolds.

Thanks Ranger, I will keep researching!

chevelle
04-25-06, 10:33 PM
No. The heads from a 2000 and later Northstar are completely different parts from the 1993-1999 Northstar cylinder heads. The later heads have roller cams with roller rocker arms for example where the earlier heads have direct acting hydraulic tappets. There are many differences including the coil-at-plug arrangement on the 2000 and later heads.

If you are looking for heads for an earlier model Northstar there are two basic versions. The 93-94 cylinder heads are common and the 95-99 heads are basically common. The 93-94 heads have different intake bolt patterns and EGR/PCV passages in the heads. It is really not feasible to swap the 93-94 heads with the 95-99 heads due to the differences in the EGR and intake manifolds. It is "possible" if you use the complete heads/intake manifold/water crossover/etc. in the swap but if you are just interested in the heads keep them within the model years indicated.

RATZLAFF
04-25-06, 11:30 PM
No. The heads from a 2000 and later Northstar are completely different parts from the 1993-1999 Northstar cylinder heads. The later heads have roller cams with roller rocker arms for example where the earlier heads have direct acting hydraulic tappets. There are many differences including the coil-at-plug arrangement on the 2000 and later heads.

If you are looking for heads for an earlier model Northstar there are two basic versions. The 93-94 cylinder heads are common and the 95-99 heads are basically common. The 93-94 heads have different intake bolt patterns and EGR/PCV passages in the heads. It is really not feasible to swap the 93-94 heads with the 95-99 heads due to the differences in the EGR and intake manifolds. It is "possible" if you use the complete heads/intake manifold/water crossover/etc. in the swap but if you are just interested in the heads keep them within the model years indicated.

Thank You chevelle, I am curious about the differences! I have a chance to get an excellent set of very low mileage 2002 heads and I thought it might be a good idea since I have to do the head gaskets and inserts in my high mileage 1998 seville sts. It now appears it may not be worth the effort?

chevelle
04-26-06, 09:00 AM
Thank You chevelle, I am curious about the differences! I have a chance to get an excellent set of very low mileage 2002 heads and I thought it might be a good idea since I have to do the head gaskets and inserts in my high mileage 1998 seville sts. It now appears it may not be worth the effort?


It really isn't practical to put the newer heads on your 98. It is technically "possible" (anything is possible with enough $$$$$$ LOL) but you would have to change the intake manifold, water crossover, etc... and a lot of things wouldn't line up perfectly. Much wiring hacking to do also. Just not practical at all. I would say impossible on a shade tree basis.

There isn't anything to gain in any case. The earlier heads actually flow a little better overall so the later model heads offer no performance gains. Some gain in fuel economy due to the lower friction but not a practical change.

Your heads should be perfectly fine. There is really nothing to go wrong with them even at high miles. They won't even need a valve job or anything. Just replace the head gaskets and carry on.

parts68
04-27-06, 05:41 AM
I think that the 4.0 Aurora heads are a little different,maybe combustion chamber size???