just curious to why my Z is eating plugs? 383 400 rwhp plugs look fine when their out one was dead after the dyno. and now its doin the same thing just not a totally dead plug. i have the ltcc coil conversion set up on it this time im gappin em at ..055 last time was.035 maybe theyre makin too much heat and kill the plugs...any help on this one would be alot of help.... tr5's are in now tr55's goin in today....

 

the plugs are actually deteriorating or they are just fouling out?

I am assuming it is the latter, and in that case, it sounds like a heat range cooler and/or wider gap may help.

 

just fouling out i guess, they look fine when theyre out.. i had the autolite 106's in at the dyno and fouled one on the way home... i put the tr5's in and maybe got 2-300 miles and now ones missing again... im stumped, maybe opening up the gap to .055 or bigger will help. i dono

 

Confusing.... a fouled plug would look black. But yours "look fine".

A larger gap won't help. The stock gap is 0.050". I wouldn't go any larger than that. The LTCC should work fine at 0.050", but dropping to 0.035" should help more than going larger.

Its still not clear to me exactly what's happening to the plugs. In one case, appears you had a bad plug. Now you have a misfire and you are assuming its the plug?????

The 106's should be OK too. If you are running it flat out for extended periods of time, a one step colder plug would help. But a "too hot" plug would show up with an enlarged gap from burned electrodes. A "too cold" plug will foul and carbon up. If the plugs are niether fouled or burned, it may be a plug wire or one of the coils.

 

yes its the plugs when i change em and put new in the problem is resolved
i dont get it either its really pissin me off this will be the 4 time this year and only put about 1000 miles on em.... ls1's gap is .060 why couldnt i got .055 ? or .060?

 

The guys that built my engine have done several LT1's using 8 LS1 coils, including mine (~500flywheelHP NA). They set the plugs at 0.040 with AutoLite 104's for pure NA driving on the street. That's based on numerous engine and chassis dyno pulls. As I add nitrous, the gap drops.... 0.035 for 103's with a 125-shot, and 0.028 for super cold Champions with the 300-shot.

Non-platinum plugs will erode enough in 15-20K miles that a plug starting with 0.060 is going to open up too far to fire. That's not a problem with a platinum plug, sinces there's less erosion with time.... (assuming the platinum pucks don't fall off ).

 

well i changed the plugs still does the same damn thing i dont get it. wires are fine too.. misses like hell from a stop to start. it ran fine last time i had it out. ever since ive had this car its hesitated days then runs awesome then back to the same ****. Its got ltcc new opti wtf... no vac leaks i just dont get it.... i think its time to say buh bye, its an endless money pit. ive went through 4 sets of plugs this year and now its back to somethin else being the problem...and of course it wont throw a code go figure...

 

Plugs don't just quit workin like that unless they are oil or gas fouled, and that's obvious to anyone when they see it. You have something else wrong there. If you have a plug gap too large, then it takes a lot of voltage to fire it, and it tries to find ground through the plug wires or any other insulated part of the high voltage secondary - in your car - that's just the coil & wire. Or maybe you just got a bad coil ground or coil that's getting too hot sometimes or something like that. Assuming it's an ignition problem. Suggest you run it in a dark garage and maybe spray it with a water mist and look for sparks.

 

How about a little info, like the year of your car? If its a 95-97 did you check the cam dowel pin length before you installed the new Opti?

How did you verify "the wires are fine too"?

What kind of results did you get on the dyno? Any flat spots or indications of misfires?

 

the dowel pin legnth is exactly the same... it ran awesome on the dyno..I think im gona try some taylor wires. its got stock wires now their bran new...........................

 

yeah once again it ate a wire... it dont matter how good u route em they still get to the headers...

 

I disagree. I haven't had a problem with mine (~3 yrs). I run mine OTVC though.

 

yah, well i have ltcc and the wires go down below,.

 

You can mount the coils on the valve covers and just drop the wires down. Burnt wire problem solved.

 

mounting on the v/c's makes the engine look like a rats nest ....