4 Cam Spark plugs
- Bill Sargent
- 356 Fan
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- Tag: Faux-Cam
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4 Cam Spark plugs
What spark plugs are 587/1,2&3 owners running for street use?
I have been running Bosch silver W4CS and have occasional fouling even with twin CD boxes.
I have been running Bosch silver W4CS and have occasional fouling even with twin CD boxes.
Regards,
Bill Sargent
#151489 59A Cab - Faux Cam
#159176 64C Cab
#460603 67 912
904 clone in the works
Bill Sargent
#151489 59A Cab - Faux Cam
#159176 64C Cab
#460603 67 912
904 clone in the works
- Harlan Halsey
- 356 Fan
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- Joined: Fri Mar 02, 2012 2:05 pm
- Location: No Cal SF Peninsula
Re: 4 Cam Spark plugs
Bill,
I have no experience with 587 engines but 692 and 547 normally run retracted side gap plugs which have had a fouling problem since day 1. Faced with that issue in 1980 I solved it by running projected nose plugs. To make room I relieved the piston crown with a 1/2-inch ball end mill. I modify the projected nose plugs into side gap plugs to minimize the depth of the relief. I've never had a plug foul. A side benefit is that my plugs cost $3.00 each rather than $30.00 each.
I have no experience with 587 engines but 692 and 547 normally run retracted side gap plugs which have had a fouling problem since day 1. Faced with that issue in 1980 I solved it by running projected nose plugs. To make room I relieved the piston crown with a 1/2-inch ball end mill. I modify the projected nose plugs into side gap plugs to minimize the depth of the relief. I've never had a plug foul. A side benefit is that my plugs cost $3.00 each rather than $30.00 each.
Last edited by Harlan Halsey on Tue Apr 05, 2022 5:12 am, edited 2 times in total.
- Martin Benade
- 356 Fan
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Re: 4 Cam Spark plugs
A hotter plug doesn’t prevent fouling? Or will that cause detonation?
Cleveland Ohio
62 Cabriolet
56 VW
02 IS 300
04 Sienna
62 Cabriolet
56 VW
02 IS 300
04 Sienna
- Jeff Adams
- 356 Fan
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Re: 4 Cam Spark plugs
The W4CS is what we run on all engines with pistons that clear the plug electrode. Are the plugs fouling with fuel or oil? Or both??
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Re: 4 Cam Spark plugs
For engines with carburetors, I pulled out Bosch spark plugs from my shelves since many years! NGK is my Friend! Wider thermal range and higher fouling resistance!
You have more chance to see Vladimir Putin on a gay pride's float than to see a fouled NGK spark plug!
As I'm at home, I don't have my "secret book" with me so I can tell you right now the NGK reference.
Anyway, I think that it's easy to find the right number with a cross reference table.
You have more chance to see Vladimir Putin on a gay pride's float than to see a fouled NGK spark plug!
As I'm at home, I don't have my "secret book" with me so I can tell you right now the NGK reference.
Anyway, I think that it's easy to find the right number with a cross reference table.
- Harlan Halsey
- 356 Fan
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Re: 4 Cam Spark plugs
+1
NGKs in all my 356s.
NGKs in all my 356s.
- David Jones
- Classifieds Moderator
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Re: 4 Cam Spark plugs
I just bought 2 x 4 packs of NGK BPR6HIX for $16 a pack, which was a deal I could not resist. Yes all my cars are wearing them.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715
Cymru am byth
David Jones #9715
- Jeff Adams
- 356 Fan
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Re: 4 Cam Spark plugs
I have not seen any difference in fouling resistance between NGK, Bosch, or any other brand in either four cam or pushrod engines. We stick with the W4CS for four cam and W6BC for pushrod and they work fine. Regardless of plug brand, fouling is usually an indication that something else is wrong. Oil burning from a worn engine, too rich fuel mixture, poor quality plug connectors with open circuits in the resistor, old solid core plug wires that cross fire, incorrect ignition coils, and so on.
One consistent problem related to plug fouling is resistor plugs. The currently supplied WR6BC plugs for pushrod engines are so awful that Bosch should be embarrassed supplying them. Whenever possible and given a choice we use non resistor plugs in all four cam, pushrod and early 911.
One consistent problem related to plug fouling is resistor plugs. The currently supplied WR6BC plugs for pushrod engines are so awful that Bosch should be embarrassed supplying them. Whenever possible and given a choice we use non resistor plugs in all four cam, pushrod and early 911.
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- 356 Fan
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Re: 4 Cam Spark plugs
Jeff, I disagree, Bosch supplies low quality stuff or stuff near the lower side of the tolerance for vintage cars. On middle age (or older) engines, fouled plugs was, for me, a problem. I solved it with NGK plugs.
Close to the spark plug, I solved some others problems with NGK plugs cover:
For 356 (including Carrera), this little boy, available from 1Kohm to 10 Kohm, is the best that i know.
Close to the spark plug, I solved some others problems with NGK plugs cover:
For 356 (including Carrera), this little boy, available from 1Kohm to 10 Kohm, is the best that i know.
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- 356 Fan
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Re: 4 Cam Spark plugs
You might try going to NGK plugs I have had great sucess with them Alan The Stable.
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- 356 Fan
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Re: 4 Cam Spark plugs
I've been using NGK Iridium plugs for years now with no problems. The engines are set up with a custom crank fire ignition system that still uses the distributors for high tension along with new plug connectors and wires. The plugs, NGK Iridium BR8EIX, are certainly more costly but in relation to the value of a 4-cam engine and the car it goes in they seem a bargain. NGK claims more power (slightly) and better fuel economy but the real benefit comes in not having to change plugs in a Carrera with limited access and a hot engine. Spark plugs foul for a variety of reasons mainly centered around not being warm enough to self clean i.e engine start up or low speed running. Back in the day, if you had the money, your new Porsche racing car came with a factory trained mechanic to help with the running of the car. It was common place to start and warm up the car with plugs of a hotter heat range. Once warm the mechanic would then change to colder plugs that wouldn't eat holes in your crummy cast pistons.
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- 356 Fan
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Re: 4 Cam Spark plugs
A "hotter plug can help with plug fouling but you can enter the "danger zone of putting a hole in a piston. You just have to balance all the factors and stay with the coolest plug that gets the results you desire. Alan The Stable Btw the best plugs I have found have been NGK Plugs. Alan The Stable.