Spark Plugs on an 89

[BimmerE30]

I heard to use the cheap regular spark plugs on my e30. Anybody hear anything else like iridium or platinum ones?

[silversleeper]

I threw in some platinums in mine recently. Platinums are supposed to last longer so I figured it couldnt hurt. I dont know about Iridiums and all. I think thats just a big gimmick.

[AdamF 88iS]

Platinums will run like shit in any E30 except M42 cars. You NEED to use copper plugs in the old style motors. Bosch W8LCR and nothing else.

[BimmerE30]

Platinums will run like shit in any E30 except M42 cars. You NEED to use copper plugs in the old style motors. Bosch W8LCR and nothing else.

Alright cool thanks, thats what i needed to know!

[MR 325]

Bosch Supers are decent

[nando]

platinums are a waste of money, generally. I can replace the basic ones 3-4 times for the cost of one set of platinums, and they DON'T last forever..

[silversleeper]

what exactly causes the platinums to run crappier than the coppers?

[AdamF 88iS]

what exactly causes the platinums to run crappier than the coppers?

I haven't actually looked into it; but I've run into the issue many times at work. For whatever reason M20s and M30s have an allergic reaction to platinums. Lumpy idle is usually the first symptom of it.

[silversleeper]

i installed some recently, and the thing is running nice and smooth.

[hamann318is]

Platinums will run like shit in any E30 except M42 cars. You NEED to use copper plugs in the old style motors. Bosch W8LCR and nothing else.

I knew I didn't need to change my +4s when everyone said they were bad for the M42.

[AdamF 88iS]

i installed some recently, and the thing is running nice and smooth.

Give it time.

[quan325i]

I've been very happy with NGK plugs. They're a little expensive but last a long time. Smooth idle.

[Mystikal]

i installed some recently, and the thing is running nice and smooth.

Give it time.

The man speaks the truth. These motors HATE Platinums.

[arsevader]

what exactly causes the platinums to run crappier than the coppers?

The issue is not the platinum per se but the size of the electrodes. Older engines tend to run a little rich when cold anyway and these plugs will foul more easily. The electrode on these plugs is tiny.

Platiunum plugs are actually cheaper here than the coppers. That tells you how much platinum is actually in one of those plugs. The metal Platinum is way more expensive than copper.

Use the stock coppers on the 325i's and the stock silvers on the ETAs and you'll be happy.

James

[BimmerE30]

what exactly causes the platinums to run crappier than the coppers?

The issue is not the platinum per se but the size of the electrodes. Older engines tend to run a little rich when cold anyway and these plugs will foul more easily. The electrode on these plugs is tiny.

Platiunum plugs are actually cheaper here than the coppers. That tells you how much platinum is actually in one of those plugs. The metal Platinum is way more expensive than copper.

Use the stock coppers on the 325i's and the stock silvers on the ETAs and you'll be happy.

James

Really they are cheaper there?? I can't find them cheaper anywhere. Anyway I changed them out and the car runs well. I made 24mpg goin 85-95 on my trip back from LA to Phoenix. I was getting only 16mpg before I changed them out.