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2001 DTS
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95 Posts
Discussion Starter #1
There's a nice condition DTS needing an engine locally and I've got a Y code engine. I've located an 03 STS engine in unknown condition I could take the intake cams from if they're a match to swap into the Y code engine--of course the bad DTS engine cams could be good too.
If doable, what else should I pull from the 9 code engine to use in the Y code to use in a 9 code car?
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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VIN 9 (STS, DTS, ETC) cams from 2000 - 2004 are quite different from the same years of VIN Y (SLS, base/DHS, ESC) cams.

The 9 PCM is very different from the Y; so is the final drive transmission ratio - 3.71 vs 3.11, which puts the 9 power curve higher in the rpm scale.

Many of the engine power differences come from PCM calibrations for everything from air/fuel mixtures to ignition timing to shift points. So, within the 2000 - 2003 Northstar run, many engine parts would swap over.

A 9 engine will not run correctly on a Y PCM and vice versa. If you swapped in good cams from a 9, then a Y engine becomes a 9 - but it must run on the original 9 PCM.

Here's the 2000 - 2003 Northstar GM brochure dyno runs for the 2 power options - all done with cams and calibrations. Note the different rpm of the max power/torque figures. The VIN Y gets on the pipe a bit earlier in the rpm curves but it fades away as the VIN 9 gets into its power band. The 9 was touted as the "performance" option; the Y was the "economy" option.

dynorun.jpg
 

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Registered
2001 DTS
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95 Posts
Discussion Starter #3
Right, I'm proposing using a Y engine, installing 9 VIN cams to install in a 9 VIN car. While possibly using STS 9 VIN cams in a Y DeVille Engine, but probably the 9 VIN cams from the orignal DTS car.
 

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Registered
2001 DTS
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95 Posts
Discussion Starter #5
Not following why this is confusing. The diff in Y and 9 codes engines is the intake cams. Is there anything else that has to change to do this; changing a Y VIN to a 9 VIN spec to use in a 9 VIN car? Cleared up better?
 
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