[chevyIIheavy]

ok i just got done talking with a buddy whos says that my distributer is retarding itself at the top end of the track he says every after market disributer does this i dont beleive him im asking cause i was running 40 degrees total at the track this weekend and my plugs where still brown this is on 91 octane so he told me that i have my timing at 40 but at high rpm its retarding itself to 36 im running an msd probillet and a 6 al box. is this true anyone want to inlighten me before i make a mistake :yes:

 

[veno]

nope your not getting any retard.... be sides if ya did... you would run faster.....

the 6al does not have a window switch for retard at high rpm... you have to buy the add on window retard switch..

 

[MarkW]

Use a timing light and a timing tape and see. If you rev it up until it stops advancing and it reads 40 deg that's what it will be at the track. Some HEI distributors do retard at high rpm but if you set it by revving it till it stops advancing it doesn't matter. What you see is what you'll have. If you advance it too much the plugs will still be brown but they'll have black speckles from molten aluminium (pistons). Plug color comes from jetting.Try 2 steps smaller jets and 38 deg timing.

 

[chevyIIheavy]

thanks guys i tried to tell him that but he didnt beleive me i thought light siver specs on the porcelain was pistons well anyways i hope more people read this im looking for all the info i can get and yes i do rev it up well above 3000 to set my advance i dont care to much about initial i was thinking of locking it out but heard this is not a good idea to do on the street its a mechanical distributer ( no vacume adv.) also this pass weekend it was really hot in ca we had a www.pscaracing.com event and my car picked up when i gave it more timing the motor didnt pop or snap going down the track. although when i did burnouts it would bog down bad ( is this the power valve ) and my 60 ftrs where crappy i had traction issues all weekend long :yes:

 

[6NOVA4]

Use a timing light and a timing tape and see. If you rev it up until it stops advancing and it reads 40 deg that's what it will be at the track. Some HEI distributors do retard at high rpm but if you set it by revving it till it stops advancing it doesn't matter. What you see is what you'll have. If you advance it too much the plugs will still be brown but they'll have black speckles from molten aluminium (pistons). Plug color comes from jetting.Try 2 steps smaller jets and 38 deg timing.

ok sorry but I have to add to some facts. Specks of aluminum piston will NOT make black speckles. The black speckles are from detonation. Either too much timing or too hot a plug. Also too hot of a plug the porcelain will look shiny. Piston material will transfer but it you will see specks of silver.(makes sense right)
the brown you see on the porcelain is fuel splash from driving the car around under idle and cruising operations. It can be from the dyes they put in gasolines or from oil burning in the chamber or a rich condition. It usually happens in one spot because that side of the plug is facing the intake valve. The only way to get an accurate plug reading is to install a fresh set of plugs and immediately make a full throttle pass. Shut it off at the end and pull the plug or plugs.

Here is a good article on plug reading
http://www.dragstuff.com/techarticles/reading-spark-plugs.html

 

[chevyIIheavy]

thanks 6nova4 for more info thats what i thought as well with the metal specs on the spark plug :yes: one question though what would cause one plug to be yellow at the tip but brown at the bottom after a pass i pulled # 4 plug and it was yellow at the top but all the rest are brown ive never seen this before :no: i should also state that i cut back my ground strap to half of the electrode my plug are champion rc12yc if this helps