Spark Plugs

[Sehrgut]

What are the best spark plugs for my 1984 944 NA? I just pulled and checked and there were NGKs installed. I'm thinking Bosch 4477 Platinums. What are your thoughts or opinions? Thanks!

[djantlive]

I like NGk more. Copper is better than platinum except they don't last as long. Given how easy it is to change our plugs, I opt for copper and swap every 60k mi

[thomasryan]

it will run better on old school plugs ..I run $2 ngks

[Chunkerz]

Bosch Super Plus copper

[v2rocket_aka944]

NGK is best.

Platinum isn't worth it unless your plugs are hard to change, which they aren't on a 944.

[924CarreraGTP]

NGK is crap. I wouldn't put them in a lawn mower. Every motorcycle I've ever owned fowled NGK spark plugs. Do yourself a favor and use Denso Platinum TT's the number is 4502. These plugs are the best thing I've ever run in a Porsche 944 or 928 engine. Something about these U-groove plugs wakes the engines up pretty nicely.
I spent 6 months throwing parts at my '83 928 to make it run like my '84 928. I finally figured out that it was the spark plugs.
As stated people seem to like NGK's but I quit them a long time ago. Get a couple of 2 stroke dirt bikes, or even a street bike and see how many times you get stuck out in the woods or your bike won't start when they get just slightly old. You'll curse them after that. Trust me...

[v2rocket_aka944]

Originally Posted by 924CarreraGTP

NGK is crap. I wouldn't put them in a lawn mower. Every motorcycle I've ever owned fowled NGK spark plugs. Do yourself a favor and use Denso Platinum TT's the number is 4502. These plugs are the best thing I've ever run in a Porsche 944 or 928 engine. Something about these U-groove plugs wakes the engines up pretty nicely.
I spent 6 months throwing parts at my '83 928 to make it run like my '84 928. I finally figured out that it was the spark plugs.
As stated people seem to like NGK's but I quit them a long time ago. Get a couple of 2 stroke dirt bikes, or even a street bike and see how many times you get stuck out in the woods or your bike won't start when they get just slightly old. You'll curse them after that. Trust me...

the 944 came with NGK plugs from the factory, not bosch
maybe the plugs you were using were the wrong heat range if they got fouled.
i just swapped plugs on my 944 for the first time since 2005, never had any issue with the old NGKs, so new ones went in...only replaced them because i was doing some other work anyways.

[thomasryan]

The quad tip bosch, which Audi used starting in the early 80s, i believe was to aid with cold starts...they where high dollar back then.

I am not much on foofoo plugs. Yes, that special tip will last longer but it is usually the grounding electrode that wears away and increases the gap. Old school cars, you changed the points and plugs every 10k or so...back when plugs where easily accessible. Modern cars have made plugs inaccessible so hence the need for forever spark plugs.

In my opinion....Huge gaps increase the resistence so that also increases the chance of tracking and arcing in the cap...which goes through the magnesium housing...then you have drama))lol

[v2rocket_aka944]

Originally Posted by thomasryan

Modern cars have made plugs inaccessible so hence the need for forever spark plugs.

my subaru, with an early-style DOHC engine, pretty much requires the engine to be removed to change the plugs

[thomasryan]

H6 tribeca, the early one....coil on plug so the motor needed to be lowered to swap them.

Fabulous motor....does suck down some oil if you pound the redline for an hour.

[Porscharu]

Originally Posted by v2rocket_aka944

my subaru, with an early-style DOHC engine, pretty much requires the engine to be removed to change the plugs

It is doable, but you have to have the right combination of sockets, adapters, and extensions. Driver's front is the worst only because the frame rail is so tight. I recommend NGK's laser iridium plugs. Changed mine just shy of 100k and they looked practically new.

[thomasryan]

OT, but do you guys use the subaru coolant additive? It is supposed to make the head gasket last longer.

My ex roommate is going to sell me his 2 door RS when he gets something else payed/paid off. Non turbo but wicked fun. Bears have trashed it, an 01 and no fluids have ever been changed except for the engine oil and the coolant when a metal heater line rusted out. Poor car but it is a two door.

[sausagehacker]

About to get OT...Helped a friend do plugs for the first time on his 2010 Forester NA and there was one where we had to get creative with u-joints or something, it was hysterical. He watched me do the plugs on my 944 and was immediately annoyed at how easy it is on these cars.

Re: Subie coolant... there was an issue where the coolant contributed to HG failures because it was getting electrically charged or something. Just what I've heard from Subaru buddies and NASIOC posts. I think it was something to do with the coolant chemistry.

On topic, my car has been problem free on NGK BPR5ES plugs. I've pulled them a few times and they are fine.

[v2rocket_aka944]

Originally Posted by thomasryan

OT, but do you guys use the subaru coolant additive? It is supposed to make the head gasket last longer.

My ex roommate is going to sell me his 2 door RS when he gets something else payed/paid off. Non turbo but wicked fun. Bears have trashed it, an 01 and no fluids have ever been changed except for the engine oil and the coolant when a metal heater line rusted out. Poor car but it is a two door.

bought my outback in march, it's a 97 with the 2.5dohc.
head gasket was done maybe 2 years ago. i have service records !
i havent done anything to it except change the oil, put steering rack dust boots and tie rod ends on it, so i don't know about the coolant but i suspect it was the cheap stuff.

your RS should have the same engine as my car, i think the 01 was the last of the 2.5dohc motor in that car.
good car, but anything but fast.

[djnolan]

Originally Posted by thomasryan

Huge gaps increase the resistence so that also increases the chance of tracking and arcing in the cap..l

You only get huge gaps after the platinum coating wears off, then the gap increases 10x faster. You will know it when it does...

If you ask me the 100k sparkplug is the greatest invention since sliced bread...

[924CarreraGTP]

Originally Posted by v2rocket_aka944

the 944 came with NGK plugs from the factory, not bosch
maybe the plugs you were using were the wrong heat range if they got fouled.
i just swapped plugs on my 944 for the first time since 2005, never had any issue with the old NGKs, so new ones went in...only replaced them because i was doing some other work anyways.

No the heat ranges were correct as I used the specified plug from the owners manuals/shop manuals. NGK's just die. They don't fowl and come back with a cleaning. They just die forever. One of my bikes was a twin and every time one of the NGK's fowled I would try cleaning it and it would just drop the cylinder again after 1 minute of running. They're like Bic butane lighters. They work great until they are used up and then you throw them in the trash. The same bike would run Denso plugs or even Champions for an eternity and never fowl them. I even told a bike shop this, but they are so dead set on NGK's they don't listen. Whatever floats your boat, but I'm telling you. Denso TT's run really nice in the 944/928 engines. Try them and you'll never go back.

[944tothefloor]

Originally Posted by Chunkerz

Bosch Super Plus copper

NAILED IT!!!
my 951 loves these plugs. loves them more than any other. of course there has to be a downside, and it's that copper wears more quickly than other materials. but i want performance, not 100k mile plug.

[beamishnz]

I had problems with iridium plugs fouling. Changed to Bosch Super Plus copper and never had a problem. My owners manual for a '91 S2 stipulates Bosch Super Plus. Speaking to specialist shops who prepare 944 race cars they all recommend the Bosch Super Plus too (for road and race) so that is what I've stuck with.

[DannoXYZ]

Annother annoying thing about the platinum tips is sometimes they get loose and fall out. Then shorts out against the ground-electrode and causes misfires. Or in unlucky cases of the X4 plugs, the loose electrode can get jammed in the rings and cause major damage to the bores.

Yeah, I've had way better performance and longevity with the NGK copper plugs compared to any of the boutique plugs.

[BoulderGeek]

I just went back and checked, and these were what I put in my NA:

Bosch (7900) WR7DC+ Super Plus Spark Plug

With the Bosch premium hi-temp silicone coated plug wires and new distributor cap and rotor, it sings.

Prior owner had the quad tipped platinums, but they were coked and looked raw. Figured fresh OEMs would be better.