Northstar Engines and System Technical Discussion Discussion, Difference between VIN Y and VIN 9 in Cadillac Engine Discussion; Can Someone Tell Me The Differences In The 2 Engines From A 96 - 99 Eldorado Or Seville...
Take a look at your VIN. The 8th character will be a 9 or a Y. The engine itself also has a "VIN derivative" stamped in a pad on the lower right front side of the block.
Otherwise, read the Northstar Performance threads, go back a month or so and find AJxtcman's posts on Northstar cam numbers. It's all in here, somewhere.
Thanks for the reply, I ask becouse a friend bought a 98 STS with a hard knock in the engine ( I think it could be a rod), and he found other 97 northstar engine and bought it for the STS, but we don't know anything about the vin of the donnor car, so, this is why I ask. We allready have the engine, and don't find any to identify this other engine. I also must say that when he bought this engine, we was thinking that all northstar engines were equals, less little changes over years.
I think you donīt need that I say that I am new in cadillacs. My other cars are a 91 Trans Am and a 73 Camaro.
The 94 will have different heads, which will need some modification, and there's a bolt hole for the RH engine/trans mount that will be non-existent on the '94, and you will need to drill & tap a hole for the knock sensor between the #3 and #5 cylinder under the intake. I'm sure I could think of other little issues but you'd be better off starting with the correct year engine. It can be done though.
Yes it is OBD1, but if you use the 99's intake plenum & TB, you've already taken care of most of the sensors. I believe the CKP/cam pos. sensors are the same from 93-99, and so is the crankshaft reluctor wheel. The only thing you would have to do is relocate the mounting for the knock sensor and use the '99's, because in 1996 the knock sensor & its location was revised. Oil level and pressure sensors I'm not 100% sure but they can easily be transferred.
The issue is the "cuts" in the intake ports. This would pose a serious vacuum leak if they weren't filled up prior to bolting down a 95-99 intake plenum. JB weld or something similar would do the trick, provided that what ever you use, would never break loose and fall into the ports.