: Northstar chips, cold air intakes, and spark plugs

05-25-14, 05:04 PM
I just picked up my 2002 Eldorado after having a head stud kit installed by Carroll Custom Cadillac. They had recently relocated to Texas just north of Dallas. After years of denial, I finally accepted that my overheating problems had only one possible solution. So far so good. I can provide details if anyone is interested. I also had CCC install a cold air intake, iridium plugs and a performance chip.

05-25-14, 05:16 PM
You car came with a cold air intake from the factory that flows more air than the engine can handle at WOT, at redline.

Iridium plugs do nothing for performance. They just last longer. Platinums will last 100,000 in your engine...

There is no such thing as a performance chip for your car. 2002 Northstars do not have "chips".

Hope they didn't charge you any extra for these NON performance parts.

05-25-14, 06:01 PM
There is no such thing as a "performance chip" for our PCM controlled cars. There IS a ripoff 25 resistor in a $65 box that offsets the IAT signal to tell the PCM to richen the fuel mixture - the magic box does nothing for performance (were you supplied with before and after dyno runs ?) but will cost you some gas mileage from the overly rich fuel mixture.

Same for the so-called "CAI". The car came from the factory with a perfectly adequate CAI installed - Dyno runs tell the truth.

Iridium plugs are cutesy - but compared to the stock #41-987 Double Platinum plugs they accomplish exactly nothing. "But Iridium plugs have a fine wire center electrode for hotter spark !!!" So does the 41-987. "But NGK Iridium plugs are really nice and made in Japan !!!" The 41-987 is made in Japan by DENSO. (read the box)

06-10-14, 08:06 PM
Don't know too much about them, apparently chips do exist.

06-10-14, 08:46 PM
Please read Posts 2 and 3.

Have at it - BUT be sure you do before and after dyno runs for reference, and keep careful manual (pen & paper) fuel use logs. Noise, feel, and subjective "power" is useless: It's the power on the pavement that is the undeniable proof.

Dyno runs are not cheap, and to verify "performance gains" from the posted 3 "modifications" it would take FOUR [before, after, after, after] dyno runs to verify/catalog the "improvements". For that kind of money the owner is entitled to the proof. (Why at least 4 runs ?? Because you NEVER slap on a bunch of mods and do one run - you work methodically and verify each mod in turn: It's all too easy to actually take a few steps backwards in the modification business.)

If the "chipper" company has a really functional magic box, they will post the details and dyno runs right here - any opportunity to create business. Don't hold your breath.

06-11-14, 08:23 AM
20MHz ???

i'm sold :thumbsup:

07-05-14, 12:09 PM
I guess we're splitting hairs here but to say chips don't exist for Northstars is technically incorrect. They do exist, are they worth any performance gains? Possibly, (probably), not. You're correct in having a dyno to absolutely verify, one way or another, any performance gains or loses. Dyno work IS expensive and time consuming, I know, I owned one and spent lots of time and money on software and schooling for a couple of years before the economy crashed. BTW, the 'chips' using the resistor to 'fool' the IAT tend to lean out the mixture not richen it, most ECUs are programmed overly rich for WOT, it's the manufacturers way to keep the exhaust temps down saving the catalytic converter., emissions don't ya know. Some magazine testing reportedly have a 'tuner' go into the program of the ECU, shut off the enrichment so the performance figures are higher than the public can ever seem to achieve. You're also right about the "chipper company", if they are legit, they will have to report verifiable increases or they will cease to exist.

07-05-14, 12:28 PM
"Chips", as in removable/plug in ECM boards/prom chips, DO NOT exist for Northstars. A BS wire in "module" that alters IAC output is not a chip. Most literally do nothing more than light up the status LED, and the respond the circuitry is full of dead ends. The ones that do change the output are just causing incorrect fuel ratios.

07-05-14, 01:09 PM
The Northstar PCM works very hard to maintain dead-nuts correct fuel mixture ratios - and all emissions controls bypass at WOT. The mixture is NOT set "lean" for emissions. The "chipper company" apparently makes "chips" for every car on earth !!! Read their website. Pure snake oil and Midway carnival pitchman advertising.

The 25 cent resistor used to offset IAT is a scam - of the worst sort. In some (earlier) Northstars the IAT is separate and set into the intake air ducting near the air filter box. In later models the IAT thermistor is incorporated in the 5-pin connector at the divorced MAF. The IAT "sensor" is the tiny black bead at the edge of the bore by the 5-pin connector. Been there, done that with 12 different resistor values. No joy.

The "performance MAF" from JET or Granatelli is also a scam - it's nothing more that a mechanically modified DELPHI MAF - center bridge milled with holes, airfoil and flow straightener honeycomb removed. Guess what ? They set lean mixture codes from incorrect airflow, cause a midrange stumble and actually lessen fuel mileage and engine responsiveness. Been there, done that, too. Threads and fuel mileages posted on 2,000 miles of highway work I did some years back.

Some hints and ideas down in Engines: PCM tuning. (The Northstar PCM maps for 2000 - 2005 have not been cracked.) Several Northstars in these forums are running on stand-alone management systems - in Fieros, sand rails, a '35 Ford Vicky and the twin Northstar 4WD Eldorado. You can diddle with those systems to your heart's content - not so with the PCM-controlled FWD Cadillacs.


07-05-14, 01:17 PM
Comparison of 2000 and later stock and JET MAF .................

07-05-14, 01:33 PM
Moderator note: Because this series of posts, and the one that fostered them, was a hijack of a specific named product thread, I have created a new thread on specifically the "tuning" subjects in the first post.

07-07-14, 02:29 PM
and the only thing that "CAI" is going to do is give you that intake roar.

07-08-14, 04:00 PM
and the only thing that "CAI" is going to do is give you that intake roar.

And most of the time you end up with a HAI ( hot air intake)

07-08-14, 04:31 PM
........... you been hard to find lately ...........

For the "CAI" dreamers, invest in either a ScanGauge-II or an UltraGauge. They plug into the OBD-II or CAN port (1996 and later) and allow you to view any 4 of a slew of "gauges" fed by the serial datastream in the car. (plus, they are also code scanners and fuel computers) I watch IAT, MAP, IGN, and ECT all the time.

The Acronyms sticky ^^^

07-08-14, 07:20 PM
[QUOTE="Submariner409;12794442"]........... you been hard to find lately ...........

Who me sub I check in about once a day, but I have been very busy in my shop just haven't seen any northstar powered cars in a while. I do have my first aurora coming in soon for a stud job. Been playing with my truck putting American Racing Headers long tubes on, 4.56 gears blistein shocks all the way around and than a Black Bear Performance tune

07-09-14, 01:22 PM
I also had CCC install a cold air intake, iridium plugs and a performance chip.

They should have thrown in a couple boxes of moth balls too.

07-09-14, 01:25 PM
Hah !!!!!! ^^^^^^

Way back in the Dark Ages I put moth crystals in the tank of a Briggs&Stratton rotary mower. The muffler glowed bright red just before the piston melted and threw the rod out the side of the block.

07-11-14, 09:59 PM
Same for the so-called "CAI". The car came from the factory with a perfectly adequate CAI installed - Dyno runs tell the truth.

While reading a bunch of posts here awhile back... isn't there a post about a guy who dynoed his Northstar and he gained 7hp at the wheels by simply sticking a cone air filter right before the MAF sensor? The factory air intake location in my Deville is behind the driver's side headlamp and to be honest the intake looks small and it doesn't seem to have a whole lot of breathing room in there for the amount of air these engines can suck at high rpm.

07-12-14, 10:13 AM
I don't recall that post, but I'd doubt it.
The factory intake system is not restrictive. It can deliver all the air that the engine can pull with a WOT @ 6000 RPM.

07-12-14, 10:26 AM
Engines don't suck air - atmospheric pressure pushes air into the cylinders faster and faster as the throttle butterfly is opened.

Piston and valve action creates vacuum in the cylinders - atmospheric pressure attempts to fill that vacuum.

The intake ducting and the size of the pleated panel filter are engineered to flow more air than the little 279 c.i. engine can ingest at WOT throttle 6300 rpm redline.

Why create a hot air filter (HAI) by hacking out the cool airbox ? If you're antsy about creating some more square inches of air inlet porting, go to work with your Dremel tool, some aluminum sheet and a pop rivet gun.

Cone filters are cutesy and some have neat colors for bling, but they don't flow any more or less air than the existing panel filter will.

Here's a panel for the 4.6 Northstar next to the cone for a 4.6 Ford truck. I don't lose sleep over the differences .................

07-12-14, 01:58 PM
I found the thread that I'm talking about with the dyno graph, turns out he didn't even stick an cone filter on the MAF.


07-12-14, 04:18 PM
Yep - that was for a 2003 VIN 9 300hp STS with 3.71 final drive. Roller cam engine with late calibration. The CORSA exhaust is good for 16 - 20 hp on the same engine.

It would be interesting to see the same sort of work and dyno runs on your 275hp VIN Y 275hp '98 Deville with the 3.11 final.