Got the car running quite well now after months faffing around with weber 40's off an old holbay engine.Not the best versions 34/35.Any criticisms or comments on the plug pics appreciated.Should point out that the two which appear richer are out of the right hand carb on each bank.My engine is inclined towards the front 4.5 degrees
Rescued attachment 001.JPG

the soft sooty plug body is this normal when the middle appears ok

[Edited on 123030p://Tuesdayoc by westf27]
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No problems there as far as I can see - classic biscuit brown colour with no deposits. Number 3 looks a little leaner but nothing to worry about.

Hello,

The engine tuning book I have read suggested that you can't tune an engine on the look of the plugs. It's more that the plug temperature determines there state..

i.e plugs cold = deposits,
plugs hot = no diposits,
plugs to hot = danger of cracking etc..


i.e. you tune the engine then fit the apporate plugs that should then look "good". So there "state" only determines how far out of tune the engine is from its fully tuned state with apoporate plugs.

Any way I am no expert, just a thought...

This site puts it better than I could: plugs

Hope I'm not telling you how to suck eggs!

This might help two: plug colors..

Dan

[Edited on 19/6/07 by Bluemoon]

[Edited on 19/6/07 by Bluemoon]

[Edited on 19/6/07 by Bluemoon]

Unfortuneately - the pictures tells us very little - was this after 10 minutes idling or at full power for 10 minutes or at part throttle?
or a run round the block doing all the above.

The centre isolator and electrode just say that the plug heat is correct for preventing the plug fouling at whatever way you ran the engine before removing them - the outer ring that is more representative of the combustion chamber says that its too rich at that point.

Find a place where you can give it full power for 10 seconds or more and shut it off immediately and coast to a stop and remove them. This will give a better idea of what is happening.


Cheers

Andrew

MMMMMMMMMM the picture tells me you need to throw them crappy champion plugs in the bin and fit NGK No1 plugs

i could tell the story as to why but i dont want to bore peeps

Fit NGK you will notice the difference

A set of Champion lasted 3 weeks in my pinto engine and a new set of HT leads was fitted before I changed the plugs as I thought it couldn't possibly be faulty plugs. How wrong I was. NGK are still going strong.

Reading Spark Plugs

it is strange,but when the engine gets hot it does appear to be unstable on idle,ok on drive.Very stable idle all the way to max temp.Could this be plugs,is the fault typical of champion and why ngk are better

Goes back to the days of crypton tunning i once had a sierra taxi in for tune up says its not running smooth and eats fuel told me he had put a set of new plugs in 2 days before i asked him what type he said champion plugs mmm i said not very good told him i could get his car running very smooth by just changing the plugs to NGK told him that if they didnt make a difference then he could have them free having allready tested the plugs for many years in vehicles and never having a faulty one i proceeded to check the co and hc level which at the time was 3.5%co and 1200ppmHC

I replaced the plugs just did a check on the timing no adjustment needed brought the vehicle up to working temp re-checked the co and hc which were 2%co and 100ppmHC point proven to mister taxi driver and he was converted plus got a refund on the crappy champion plugs

There endeth my long boring story one of many in the motor trade

[Edited on 6/20/2007 by DRC INDY 7]