: Performance tune-up for 94 North*using performance coils.

11-05-06, 07:22 PM
Okay I plan on doing a full tune-up on my 94' STS and I always like to do upgrades where possible. Let me know what you think of this tune up parts list.

AC Delco plug wires $99 at Summit Racing
Summit brand 40k volt Performance coils (http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2D850017&N=700+4294908226+4294908217+4294924760+115&autoview=sku)
$32.95 each requires 4.
NGK G-Power Platinum Spark Plugs $3 each
Bosch replacement O2 sensors
Fresh oil change with K&N oil filter
Fresh clean and oil on current conical K&N air filter.

And The Westers Garage ECU chip.

What do you all think of this? The coil packs are 40k volt units similar to Accel units. This mixed with a propperly gapped platinum plug and a Tuned ECU chip should help the car run at its' full potential.


11-05-06, 07:40 PM
Forget NKG plugs. Use A/C Delco. Northstars seem to run best with them.

Same with O2 sensors. Stick with A/C Delco.

Great price on the wires.

K & N air filter is a waste of money and won't gain you a thing. Save your money and again use A/C Delco. It will flow all the air the Northstar can breath.

I doubt the coils will do anything either. I can't imagine that they will do anything more than the OEM coils on the car. All they have to do is light the fuel/air mixture.

Don't know a thing about K & N oil filters, but if they are anything like their air filters, they are overpriced.

You can verify all of this with a search.

11-05-06, 07:50 PM
A/C Delco plugs, wires and O2's it is then. I do use the search function but not everything is gone over in those posts. Coils do help get the spark across faster and hotter especially when paired with new wires and plugs. It may not be a huge HP mod but it will help throttle response and mileage. My North* has just over 160k miles and I'm looking to make it feel new again with this tune up and a fresh Coolant change. I will have the coolant checked for exhaust gasses when it is drained, that way I know if my head bolts have loosened up and let the gaskets start leaking. I might also have compression test run on all the cylinders to see how healthy this baby is. It has a freshly rebuilt tranny and torque converter so I should be good there.

Anything else?

11-05-06, 08:10 PM
Well, I would not waste money on an exhaust gas test. If it is going to happen, it's going to happen. Nothing you can do about it and you'll know it when it starts to drink coolant and overheat. If you are not having those problems, you are maintaining the cooling system properly. Keep it up.

Compression test is also not usually needed. Due to the Northstars aggressive cylinder honing pattern which reatains oil and thus uses it, the rings and walls will last damn near forever with no wear. They have been reported to have been torn down at 250K and still have the factory cross hatch pattern visible in the walls.

As far as the coils go, I would swear I recall our old Guru saying basicaly what I did, but I can't swear to it and don't know enough about it to debate it one way or the other. Personaly I would not bother, but it's one of those, your car, your money and your choice things.

The only other things you might want to do is a good TB cleaning along with the EGR and "mouse holse" in the intake manifold. I would guess that will net you more than the coils.

11-05-06, 08:28 PM
The stock ignition system will fire the mixture efficiently under all normal operating conditions. Anything else is gilding the lilly. Hotter spark does not give more power. All it does is apply more stress to the high voltage insulation and increase the chance of arcovers and misfires. AC oil and air filters are the most efficient on the market by actual scientific testing. Everything else is varying grades of overpriced junk. The reality is that the factory did a damn fine job when they built and equipped the car originally.

11-05-06, 09:10 PM
Sounds good to me. I guess I am used to older cars where an improved ignition sytem and coil pack would help out. Also On my 2v 4.6L mustang the Granatelli upgraded coilpacks net a dyno proven 15HP on a bone stock car. I figure these might do somthing for the North* since they make them for it. My car already has a K&N conical filter on it so I might as well clean it and re-oil it. The previous owner said the car runs really strong and burns no oil or coolant. We will see when it hits Houston. Just trying to gets some parts together for a full tune up when it get the cooling system overhauled.

11-05-06, 09:20 PM
Keep in mind that the K & N does not filter as well as the OEM filter. It will pass more dirt. Do a search, it has been "discussed" many times.

11-05-06, 09:25 PM
Also this car will be maintained regularly and run hard on a regualr basis. I run all of my cars hard so I usually install parts that will hold up to the beatings. That is why I wanted to tune it up with the best parts. The maintainence section said that these cars like to be run hard and don't even like to be excessivly warmed up after oil pressure it optimal. They said you should start it up let the oil pressure rise and then Go! I will probably also install all new power cables and ground wires as mentioned in the Big 3 upgrade post. I appreciate your guys expertise that is exactly why I post stuff like this.

11-05-06, 09:49 PM
Yeah, warm up is not necassary, but don't beat on it til it's up to operating tempurature.

11-05-06, 10:03 PM
Gotcha! I can't wait to start rollin' in my STS. I am in Italy right now and will be back rollin through Houston in Dec.

11-06-06, 05:18 PM
If you flog your car once in awhile, may as well go a heat range or two cooler on the plugs.

11-06-06, 10:52 PM
Next major overhaul I do (oil pan' gasket, alternator bearing, strut mounts, ect) I'll be throwing in some colder range plugs. I drive my car like I stole it, and have so for the last 56k miles. I've She's got 101k on her, and still runs like a bat outa hell. I've been thinking lately though, that with the the amount of WOT I subject her to on a daily basis, colder plugs might be the way to go. Think I might need an injector or two as well, now that this thread has got me thinking of tune-ups and what not. I know one it ticking quite loudly off an on, and I think another one may be suspect as well. At WOT, I get a nice brown cloud out of the back of my car. I've also notice that if I've got the car running and I happen to be cleaning my rear rims (after I wash my car) if I get to close to the back of the car, for too long, my eyes start to burn, and it's the same feeling I got when I used to get too close to the back of my old '66 Mustang when she was idling.......raw, unburned fuel just pouring into your face. Last time I ran a 5 gas machine on her a year ago, she was a little rich at idle but still managed to pass emissions. Anyway, enough about my car.

New coils won't really gain much at all. The coil will only produce as much voltage as is needed to jump the gap. Higher output coils are needed when running leaner mixtures, and in higher compression engines since there is more resistance keeping the spark from closing the gap. In a stick engine, running stock plug, stock a/f ratio, and stock compression....a coil with a higher max output will still produce no more voltage than a stock coil will. It's not like an old 350 where the ignition system was somewhat inadequate to begin with. The coils on even he crappiest F/I cars today are capable of well 30-40k volts if need be. The only real gain I see with using higher performance coils in a stock N*, is the fact that they will most likely have double the life span of a stock coil, since they aren't stressed as much under high load.

11-06-06, 11:21 PM
Someone explain to me what the benefit of running colder plugs is if you beat the piss out of the car? Just wondering, I'm ignorant to the whole subject.

11-07-06, 09:19 AM

All's explained there ^^^

11-07-06, 12:11 PM
Before adjusting the heat range on your sparkplugs, do like the people who know what they are doing. Take a series of plug readings.
Drive like you normally would, pull all the plugs and compare them to the pictures on the manufacturers chart using a lighted magnifier. Do Some WOT runs and cut the ignition instead of letting the engine over run. Pull over and take a reading on all the plugs again. Now you have some data to work with to make a decision on whether they should be of a colder or hotter heat range instead of a wild guess. Trained professionals get a lot of money for this kind of work. Maybe they earn it. Using plugs with a seriously too high heat range can result in pre-ignition and holed pistons. Plugs with too cold a heat range will foul and result in misfires. The plugs reccomended by the manufacturer have a broad heat range that straddles everything the owner is likely to do. Unless you putt putt around in sub-zero weather or have seriously modified your engine and race it, it is highly unlikely you can accomplish anything with a heat range change that wouldn't be a step downhill.

11-07-06, 05:58 PM
Well the more powerful coild might help out when I get Westers garage to program me a chip to match my new setup. I will tell him how it will be run and what stage plugs and what coils I am using. I will be able to widen the gap in the plugs to get a hotter broader spark from the more powerful coils for a more thorough burn. That way he can lean the air/fuel mixture out alittle more for cleaner burn and more power. I will probably be getting the car dynoed to see what it is doing and have him reprogram the chip accdoringly. Anybody know what plugs will work well with the North* and let me go 1 stage colder? I am def getting the A/C Delco wires since they are soo highly regarded.

11-25-06, 11:26 AM
People who use the open cone K&N filter will probably experience a slight loss of power on hot days.. The open filter is sucking all the hot air from your engine compartment. If you were to install a Cold Air Induction (or Intake) grabbing cooler air from the fenderwell area or under the car, then you might see a bit of improvement on the throttle response... Otherwise the stock OEM air system is pretty good in this case.. Also using a K&N filter can lean out the fuel mixture a tad causing a slight loss of low end torque.. More noticeable with 4 and 6 cylinders.... Might not be noticeable at all on a V8

11-25-06, 05:16 PM
Also using a K&N filter can lean out the fuel mixture a tad causing a slight loss of low end torque..

LOL.... no.

A K&N or similar foam filter won't do anything to your low rpm torque. Good or bad. Well, it might if the oil comes off and sticks to your MAF.

The filter only flows more air at high RPM's. You will only see a difference there - where it is flowing more. It won't be running any leaner or richer if your MAF* is working right.

*note - for a 93-95, it will run a bit leaner in the high rpm range. However, these cars run rich from the factory, so a tenth of a point leaner will actually gain you more power in itself. Not enough to be noticeable....

11-25-06, 07:30 PM
Might try to make a cold air shield to keep the engine heat off the filter. I will also fully clean and oil the K&N filter. I will probably pull the MAF and clean it out too. Still haven't installed the coils. Thats because I'm still in Italy and the car is in Houston. 3 days and I'll put em on and give her a go.